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Gii thiu Information Mc lc

Bin son ebook : L nh Sng

I HC Y KHOA H NI

Trang web : www.ykhoaviet.tk

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Mi tm lng ng h cho vic xy dng mt website dnh cho vic ph bin ti liu hc tp v

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GII THIU

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Vi tiu ch l b sch m , c xy dng da trn ngun ti liu ca cng ng , khng mang

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khi s dng b sch ny bn phi ng vi nhng iu kin sau . Nu khng ng , bn

khng nn tip tc s dng sch :

B sch ny c cung cp n tay bn , hon ton da trn tinh thn t nguyn ca bn.

Khng c bt kz s thng lng, mua chuc, mi gi hay lin kt no gia bn v tc gi b

sch ny.

Mc ch ca b sch phc v cng tc hc tp cho cc bn sinh vin Y khoa l chnh, ngoi

ra nu bn l nhng i tng ang lm vic trong nghnh Y cng c th s dng b sch nh

l ti liu tham kho thm .

Mi thng tin trong b sch u ch c tnh chnh xc tng i, thng tin cha c kim

chng bi bt c c quan Php lut, Nh xut bn hay bt c c quan c trch nhim lin quan

no . V vy, hy lun cn trng trc khi bn chp nhn mt thng tin no c cung cp

trong b sch ny.

Tt c cc thng tin trong b sch ny c su tm, tuyn chn, phin dch v sp xp theo

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B sch ny l ti liu su tm v dch bi mt sinh vin Y khoa ch khng phi l mt gio s

tin s hay mt chuyn gia Y hc dy dn kinh nghim,do c th c rt nhiu li v khim

khuyt khng lng trc , ch quan hay khch quan, cc ti liu b tr c th cha hp l , nn

bn cnh vic thn trng trc khi thu nhn thng tin , bn cng cn c k phn mc lc b

sch v phn hng dn s dng b sch s dng b sch ny mt cch thun tin nht.

Tc gi b sch in t ny khng chu bt c trch nhim no lin quan n vic s dng sai

mc ch , gy hu qu khng tt v sc khe, vt cht, uy tn ca bn v bnh nhn ca bn .

Khng c chuyn mn , khng phi l nhn vin y t , bn khng c ph p t s dng nhng

thng tin c trong b sch ny chn on v iu tr. T trc ti ny, cc thy thuc IU

TR BNH NHN ch khng phi l IU TR BNH. Mi ngi bnh l mt thc th c lp

hon ton khc nhau, do vic b nguyn xi tt c mi thng tin trong b sch ny vo thc

tin s l mt sai lm ln . Tc gi s khng chu bt c trch nhim g do s bt cn ny gy ra.

V l b sch cng ng, to ra v mc ch cng ng, do cng ng , b sch ny c pht trin

c hay khng mt phn rt ln, khng ch da vo sc lc, s kin tr ca ngi to ra b

sch ny , th nhng ng gp, xy dng, gp , b sung, hiu chnh ca ngi c chnh l

ng lc to ln b sch ny c pht trin. V mt mc tiu tr thnh mt b sch tham

kho y khoa tng hp ph hp vi nhu cu v tnh hnh thc tin trong lnh vc y t ni ring v

trong cuc sng ni chung . Tc gi b sch mong mi bn c nhng li ng gp chn

thnh mang tnh xy dng, nhng ti liu qu m bn mun san s cho cng ng , v mt

tng lai tt p hn. l tt c nim mong mi m khi bt u xy dng b sch ny , ti

vn kin tr theo ui .

Ni dung b sch ny, c th ch ng trong mt thi im nht nh trong qu kh v hin ti

hoc trong tng lai gn. Trong thi i cch mng khoa hc cng ngh tin nhanh nh v bo

nh hin nay, khng ai bit trc c liu nhng kin thc m bn c c c th p dng

vo tng lai hay khng . tr li cu hi ny, ch c chnh bn thn bn , phi lun lun

khng ngng-T MNH-cp nht thng tin mi nht trong mi lnh vc ca i sng, trong

c lnh vc y khoa. Khng ai c th, tt nhin b sch ny khng th, lm iu thay bn.

Nghim cm s dng b sch ny di bt kz mc ch xu no, khng c ph p thng mi

ha sn phm ny di bt c danh ngha no. Tc gi b sch ny khng phi l tc gi bi vit

ca b sch , nhng mt rt nhiu cng sc, thi gian, v tin bc to ra n, v li ch

chung ca cng ng. Bn phi chu hon ton trch nhim vi bt kz vic s dng sai mc ch

v khng tun th ni dung b sch ny nu ra.

Mi l thuyt u ch l mu xm, mt cun sch hay vn cun sch cng ch l l thuyt, ch c

thc t cuc sng mi l cun sch hon ho nht, bn khng phi l c gi m l din

vin chnh. V Bch Khoa Y Hc cng ch l mt ht thc nh, vic s dng n xo nu hay

nhn ging l hon ton ty thuc vo bn c. V ngi to ra ht thc ny s vui mng v

c truyn thm ng lc tip tc c gng nu bit rng chnh nh bn m bit bao ngi

khng cn phi xp hng ch cu tr.

Mi ng gp lin quan n b sch xin gi v cho tc gi theo a ch trn. Rt mong nhn

c phn hi t cc bn c gi cc phin bn sau c tt hn.

Knh chc bn c, gia quyn v ton th ngi Vit Nam lun c sng trong khe mnh,

cuc sng ngy cng m no hnh phc.

Lng, Ngh An. Thng 8/2010

ABOUT

ebook editor: Le Dinh Sang

Hanoi Medical University

Website: www.ykhoaviet.tk

Email: Lesangmd@gmail.com, bachkhoayhoc@gmail.com

Tel: 0973.910.357

NOTICE OF MEDICAL ENCYCLOPEDIA PUBLICATION 2010:

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specialties, as well as changes in presentation, Medical Encyclopedia 2010 is divided into many

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1. H TUN HON

Theo Free Health Encyclopedia

H tun hon ca c th bao gm h tim mch v h bch huyt.

Hai h ny vn chuyn oxy, cht dinh dng, nhng t bo cht, hormon v nhng cht khc

n v i khi cc t bo trong c th.

Hng t t bo trong c th ngi nhn cht dinh dng v thi ra nhng cht b hng ngy,

hng gi, hng pht.

Mc d s trao i ny c th gia tng khi hot ng v chm li khi ngh ngi nhng lc no n

cng hot ng lin tc.

Nu n dng li, c th s cht. Trong 2 h, h tim mch ng vai tr vn chuyn chnh, h

bch huyt ch h tr thm bng nhng chc nng ring bit ca n.

NHNG THNH PHN CA H TIM MCH

Nhng thnh phn chnh ca h tim mch l tim, cc mch mu v mu. C th m t mt cch

hnh tng h tim mch bng hnh nh sau: mt ci bm bng c (tri tim) bm dch (mu)

chy qua mt chui nhng ng dn ln v nh (cc mch mu) i khp c th.

Khi di chuyn qua mt h thng cc mch mu phc tp, mu ly oxy t phi, cht dinh dng

t rut non v hormon t cc tuyn ni tit.

Sau n phn phi li cho cc t bo ca c th ri ly v CO2 (c to thnh khi t bo

dng ng v m sn xut ra nng lng) v nhng cht thi khc. Mu s mang nhng

cht thi n phi v thn thi ra ngoi.

Tim Tim l mt cu trc rng, hnh nn lm t c nm pha sau v hi lch v bn tri xng

c. Np mnh vo gia 2 phi, tim c nm trong mt lng xng bo v c to bi xng

c, cc xng sn v ct sng. nh tim nm pha di, c gi l mm tim, hng v

pha hng tri v nm trn c honh (mt mng c phn cch khoang ngc v khoang bng vi

nhau). Phn trn ca tim, c gi l y tim, hng v pha vai tri v nm di xng sn

th 2, cc mch mu quan trng ca c th c ni vo tim phn ny.

Tim c kch thc bng mt nm tay. Khi mi sinh, kch thc tim v nm tay ca tr l bng

nhau. Khi c th pht trin, tim v nm tay cng pht trin vi cng mt tc . ngi ln,

khi lng trung bnh ca tim vo khong t 255 n 310 gram, ca nam ln hn ca n mt

t.

Mng tim l mt ti lm t mng x, cht, bao quanh, bo v v neo gi tim li vi cc cu trc

xung quanh. Lp mng trong bao mt ngoi ca tim v l mt thnh phn ca thnh tim. Lp

x bn ngoi bo v tim v neo tim li vi cc cu trc xung quanh nh l xng c v c

honh. Phn trong ca lp ngoi ny c gii hn bi mt lp khc, sn xut ra huyt thanh.

Cht nc bi trn gia hai lp trong v ngoi ca mng tim ny gip cho 2 lp ny trt ln

nhau c d dng hn v gim ma st khi tim p

Thnh tim c cu to bi 3 lp: lp ngoi (epicardium), lp c (myocardium), v lp ni tm

mc (endocardium). Lp ngoi cng (epicardium) tht cht l lp trong cng ca mng ngoi

tim. Lp gia, myocardium, l mt lp c tim dy c th co bp c tng mu i ra khi

tim. Lp trong cng, ni tm mc, l mt mng mng gip mu c th chy trn tru qua cc

bung tim.

Cc bung tim

Tim c chia ra lm 4 bung. Mt vch c chia tim ra lm 2 phn: phi v tri. Mi phn tip

tc c chia ra lm 2 bung: bung trn v bung di. Hai bung trn, cn c gi l tm

nh, c thnh mng. Chng m nhn chc nng nhn mu v tim. Mu chy v tm nh t cc

mch mu ca c th, sau c bm xung tm tht, l 2 bung nm pha di. Tm tht l

bung m nhn chc nng tng mu i. Thnh ca chng dy v c nhiu c hn tm nh. N

gip tm tht co bp v bm mu ra khi tim n phi v nhng khu vc cn li ca c th.

Trong khi mu chy t bung ny sang bung kia, nhng ci van-mt-chiu ngn khng cho

mu chy ngc tr li bung c. Cc van nm gia tm nh v tm tht c gi l van nh

tht. Van nh tht tri (nm gia tm nh tri v tm tht tri) cn c gi l van hai l. Van nh

tht phi (nm gia tm nh phi v tm tht phi) cn c gi l van ba l. Cc van nm gia

2 tm tht v nhng mch mu ln c chng bm mu c gi l cc van bn nguyt. Van

bn nguyt ng mch phi nm gia tm tht phi v thn ng mch phi. Van bn nguyt

ng mch ch nm gia tm tht tri v ng mch ch.

Cc l van m v ng p ng li vi nhng thay i p lc trong tim. Cc van nh tht m

ra khi tim ngh ngi v ng li khi tm tht co bp. Cc van bn nguyt ng li khi tim ngh

ngi v m ra khi tm tht co bp. Khi cc van ng li s gy ra nhng ting "bm-tc" m bc

s c th nghe thy c qua ng nghe. Khi van nh tht ng s to ra ting "bm", khi van bn

nguyt ng s to ra ting "tc".

H dn truyn ni ti ca tim

Tim c mt h thng thn kinh ring kim sot hot ng ca n c gi l h dn truyn

ni ti, nm bn trong m tim. Nhng tn hiu thn kinh c h ny gi i s lm cc phn

khc nhau ca tim co bp nhng thi im khc nhau. Mt im nt nh bao gm mt loi

m c c bit nm phn trn ca tm nh phi c gi l nt xoang. Do n l im khi

u ca xung ng nn nt xoang cn c gi l nt to nhp. H thng ny cn bao gm

nhng nt khc nh nt nh tht, nm gn y ca tm nh phi, ngay pha trn tm tht. B

nh nht (cn c gi l b His) nm phn trn ca vch ngn gia 2 tm nh. Hai nhnh

chnh t b ny chia ra thnh nhng si nh hn phn b u cc c tim ca cc thnh tm

tht. Chng c gi l nhng si Purkinje.

Mch mu

Cc mch mu to ra mt h thng vn chuyn bao gm cc ng c chiu di khong 96,500

km, hn gp i chiu di ca ng xch o. Ton b h thng mch mu c xem nh l

mt chui nhng con ng v ng cao tc lin kt vi nhau. Mu ri khi tim i vo cc

mch mu ln (ng cao tc) i n c th. nhiu im khc nhau, nhng mch mu ln

ny chia ra thnh nhng mch mu nh hn (ng l). V n lt mnh, nhng mch mu

ny tip tc chia ra thnh nhng mch mu nh hn, nh hn na (c 1 ln xe). Khi quay

ngc tr v, mu i qua nhng mch mu c kch thc tng dn ln (cc ng 1 ln hp li

thnh ng l ri thnh ng cao tc) trc khi tht s tr v tim.

MU C PHI L BIN BN TRONG C TH ?

Ch mi hn 350 nm trc, con ngi tng ngh rng mu trong c th chy ti v lui y ht

nh nhng cn thy triu vy. Ngi Hy Lp c i l nhng ngi u tin t ra l thuyt

ny. H tin rng mu ri khi tim, sau rt tr v tim mang theo nhng cht cn bng theo

cng mt mch mu. Gi thuyt ny tn ti cho n hn 1400 nm.

Nm 1628, mt bc s ngi Anh, William Harvey (1578-1657), cng b mt khi nim mi

v tun hon mu. ng xc nhn rng mu chy khng ngng t cc ng mch sau tr v

tim qua cc tnh mch v to nn mt vng tun hon lin tc qua c th.

Ngay lp tc sau , l{ thuyt ca Harvey b khinh mit v n i lp li hon ton nhng hiu

bit c bn v y hc vo thi . Tuy nhin, vo khong 30 nm sau, { tng ca ng c

xc minh do ngi ta pht hin ra s tn ti ca cc mao mch. Do l ngi tin phong nn

Harvey c nhiu ngi xem nh l cha ca nn y hc hin i.

ng mch, mao mch v tnh mch l nhng thnh phn chnh ca h thng vn chuyn. ng

mch l nhng mch mu mang mu i ra khi tim. Cc ng mch ln ri tim sau chia

nhnh ra thnh nhng ng mch nh hn ri i n nhiu khu vc khc nhau ca c th. Sau

chng tip tc chia nh hn thnh cc tiu ng mch. Trong cc m, cc tiu ng mch

chia ra thnh nhng mch mu siu nh c gi l cc mao mch. S trao i cht gia mu

v t bo din ra xuyn qua thnh ca cc mao mch. Trc khi ri khi m, cc mao mch gp

li thnh cc tiu tnh mch. Sau nhng mch mu ny di chuyn n gn tim hn v gp li

thnh nhng tnh mch ngy cng ln hn.

Nhng mch mu ln c nhng cu trc khc nhau. Mc d cc thnh ca c ng mch v tnh

mch u bao gm 3 lp nhng dy ca chng cng khc nhau. ng mch c lp trong v

lp gia dy hn, gip chng n hi hn. Chng c th co v dn d dng khi mu c bm

t tim trn qua. Tnh mch c thnh mng hn gip cc khung c xung quanh chng bp v y

vo thnh p mu trong tr v tim. Nhng van-mt-chiu thnh cc tnh mch gip

ngn khng cho mu chy ngc tr v v gi cho dng mu chy theo 1 hng. Cc van c

nhiu nht chn do mu phi chng li trng lc quay tr v tim. Khng ging vi ng

mch v tnh mch, thnh ca cc mao mch ch dy bng 1 t bo. hu ht cc mao mch,

nhng t bo ny khng dnh cht vi nhau. iu ny gip cho oxy, cht dinh dng v nhng

cht thi c th di chuyn qua li d dng gia mu v dch k lp y nhng khong khng

gian gia cc t bo.

VNG TUN HON PHI V VNG TUN HON H THNG.

C 2 vng tun hon chnh trong c th: vng tun hon phi v vng tun hon h thng.

Nhng mch mu ca vng tun hon phi vn chuyn mu qua li gia tim v phi. Nhng

mch mu ca vng tun hon h thng vn chuyn mu n tt c nhng phn cn li ca c

th.

ng mch chnh ca vng tun hon h thng l ng mch ch. ngi ln, ng mch ch

c cng kch thc vi ng nc ti cy tiu chun. N tri ln khi tim v i ln trn t tm

tht tri khong 1 inch ri sau b hng sang tri ngay pha trn tim (phn ny c gi l

cung ng mch ch) trc khi cong thng xung chia ra cc nhnh cung cp mu cho

nhng phn cn li ca c th.

Cc nhnh ca ng mch ch bao gm ng mch cnh (cung cp mu cho u), ng mch

vnh (cung cp mu cho cc c ca tim), cc ng mch cnh tay (cung cp mu cho cnh tay)

v nhng ng mch i (mang mu xung cung cp cho bp i).

Tnh mch ch l tnh mch ln nht ca vng tun hon h thng. N c 2 nhnh: tnh mch

ch trn nhn mu t u v cnh tay chy v; tnh mch ch di nhn mu t phn c th

pha di chy v. C 2 nhnh ny u mu v tm nh phi.

Cc tnh mch mu v tnh mch ch bao gm: tnh mch cnh (dn mu t u tr v), tnh

mch cnh tay v tnh mch u (dn mu v t cnh tay), tnh mch i (dn mu v t bp

i), v tnh mch chu (dn mu v t vng chu v hng).

Nhng mch mu thuc vng tun hon phi mang mu n phi trao i kh (nhn O2 v

thi CO2 ra), sau quay tr v tim. Nhng mch m chnh l ng mch phi v tnh mch

phi. Hai ng mch phi 2 bn c ngun gc t thn ng mch phi xut pht t tm tht

phi. ng mch phi phi i vo phi bn phi v ng mch phi tri i vo phi bn tri. Sau

khi trao i kh phi, mu c oxy ha (c mang oxy) s c quay ngc tr v tm nh

tri ca tim bi 4 tnh mch phi.

MU

Mu l cht dch c tim bm vo cc mch mu i n khp cc b phn ca c th. N l

m lin kt. Theo ng nh tn gi ca n, m lin kt l nhng loi m kt ni cc phn khc

nhau ca c th li vi nhau nng , cha ng v bo v. M lin kt c tm thy

khp ni trong c th v l loi m c nhiu nht trong 4 loi m ca c th (3 loi m cn li

l: biu m, m c v m thn kinh). Trong tt c cc m ca c th th mu l loi m duy nht

tn ti di dng dch.

Mu c rt nhiu chc nng trong c th. N mang tt c nhng vt cht c th vn chuyn

c t ni ny sang ni khc trong c th: oxy, cht dinh dng cho cc t bo, hormon (l

nhng cht truyn tin ha hc) n cho cc m v nhng cht thi n cho cc c quan m

nhn nhim v thi chng ra ngoi khi c th. N gip bo v c th bng c ch ng mu v

bo v c th khi nhng vi sinh vt l. N cng gip nhit c th c gi tr khng i bng

cch ly nhit ra khi t bo.

Nht v nng hn nc, mu sc ca mu thay i t ti sang c ty thuc vo lng

oxy m n ang mang (oxy cng nhiu th mu sc cng sng). Khi bn trong c th, mu c

nhit vo khong 38C. Mu chim khong 8% trng lng ca c th. Mt ngi nam gii

trng thnh c khong 5.6l mu bn trong c th, n c khong 4.5 lt. Nam c khuynh hng

c nhiu mu hn n do c s hin din ca testosterone, l mt loi hormon sinh dc nam c

tc dng kch thch s to thnh mu.

Mu bao gm c thnh phn rn v lng. Nhng thnh phn rn bao gm hng cu, bch cu

v tiu cu nm l lng trong huyt tng, l mt cht dch ging nc mu vng nht. Cc t

bo mu chim khong 45% mu v huyt tng chim 55% cn li.

HUYT TNG

Huyt tng c 92% l nc. C trn 100 cht khc nhau tan trong , bao gm cht dinh

dng, kh h hp, hormon, protein huyt tng, mui v nhiu loi cht thi. Trong s ,

protein huyt tng chim t l cao nht. Nhng loi protein ny hu ht c gan sn xut ra

v c nhiu chc nng khc nhau. Fibrinogen l mt loi protein quan trng gip ng mu.

Albumin gip gi nc li bn trong mu. Gamma globulin l mt loi khng th gip bo v c

th chng li nhng cht l.

Mui hin din trong huyt tng bao gm: natri, kali, magne, clo v bicarbonate. Chng tham

gia vo nhiu chc nng quan trng ca c th, bao gm co c, dn truyn cc xung ng thn

kinh v iu ha thng bng pH (kim-toan) ca c th.

HNG CU

L loi t bo c nhiu nht trong 3 loi t bo mu. S lng ca n vo khong 5 triu t bo

trong mi milimet khi mu (1 milimet khi tng ng vi mt git mu rt nh nhn

thy c bng mt thng). Chc nng chnh ca n l vn chuyn oxy t phi n cc t bo

ca c th. Hng cu c cu trc hnh a phng v lm xung trung tm, kch thc gip

chng c th lch vo c cc mao mch nh.

CHARLES DREW v cch bo qun huyt tng

Charles Drew

Mu c 4 nhm chnh l A, B, O, v AB, y l khm ph ca cc nh nghin cu y hc vo u

th k 20. Khm ph ny ci thin ng k hiu qu ca vic truyn mu. Tuy nhin, vo thi

im , mu ton th ch c th gi c trong vng 7 ngy trc khi b h. Do vn lm

sao c c ng loi nhm mu cn thit sn sng trong cp cu vn cn tn ti.

Vo nhng nm cui thp nin 30 ca th k trc, mt bc s ngoi khoa ngi M, Charles

Drew (1904-1950) bt u khm ph ra c kh nng dng huyt tng thay th cho mu

ton th truyn. Do huyt tng khng c hng cu nn n c th c truyn cho bt kz

bnh nhn no m khng cn quan tm n nhm mu ca h. Tnh cht ny ca huyt tng

lm cho n tr thnh l{ tng s dng trong cp cu.

Khong nm 1940, Drew pht minh ra c cch x l v bo qun huyt tng bng cch

kh nc ca n do nn n c th em i xa c v bo qun trong mt thi gian di. Khi

cn thit, huyt tng kh (ging nh bt) c th c ti to tr li dng ban u bng cch

thm nc vo.

Vic s dng huyt tng truyn mu chng t c vai tr c bit quan trng ca

mnh trong sut th chin th II (1939-1945), thi im mu dng iu tr vt thng

b thiu ht trm trng. Do nghin cu trn, ng c tn thng v cu mng c v

s ngi.

ngi ln, hng cu c to ra bi phn ty ca xng sn, ct sng, xng c v

xng chu (ty xng l mt cht tng t nh bt bin, xp c trong cc khoang bn trong

hu ht cc xng ca c th). Thnh phn c bn ca hng cu l mt loi protein sc t c

tn l hemoglobin. Phn t hemoglobin chim 1/3 trng lng mi t bo hng cu. phn

trung tm ca mi phn t hemoglobin l 1 nguyn t st to mu sc cho hng cu. Ti phi,

t bo st kt hp vi oxy to ra mt hp cht c tn l oxyhemoglobin. Chc nng chnh

ca hng cu l vn chuyn oxy di dng ny n cc t bo khp c th. Sau khi oxy c

trao i, hemoglobin kt hp vi CO2 thi ra t t bo v hng cu quay tr li phi c

thi bt ra.

Do hng cu thng xuyn b p vo nhng mao mch nh li ti nn mng ca n d b h hi v

xi mn rt nhiu do mi t bo hng cu ch tn ti trong khong 4 thng. Nhng t bo

hng cu mi c sn xut lin tc ty xng thay th nhng t bo c.

Hnh nh hng cu chy qua cc mch mu.

NHM MU.

Hng cu mang nhng protein c gi l khng nguyn, l nhng cht gip c th nhn bit

nhng vt l xm nhp, mng ca mnh. Ngi ta da trn nhng khng nguyn ny quy

nh nhm mu: A, B, AB, hoc O. Ngi nhm mu A c tt c cc t bo hng cu trong c

th mang khng nguyn A. Ngi nhm mu B c tt c cc t bo hng cu trong c th mang

khng nguyn B. Ngi nhm mu AB c tt c cc t bo hng cu trong c th mang khng

nguyn A v B. Ngi nhm mu O c tt c cc t bo hng cu trong c th khng mang

khng nguyn no c.

Bit c nhm mu ca bnh nhn l iu rt quan trng nu mun thc hin truyn mu.

Ngi c nhm mu A khng th nhn c mu nhm B v h c mang khng th chng li

khng nguyn B. Tng t, nhm mu B mang khng th chng li khng nguyn A. Nhm mu

AB khng mang khng th chng li khng nguyn no c, nhng nhm mu O th li mang

khng th chng li c hai khng nguyn A v B. Nu bnh nhn b cho lm nhm mu th cc t

bo mu s vn cc li v lm tc nghn nhng mch mu nh. Phn ng ny, cn c gi l

phn ng kt dnh, c th gy t vong.

Hng cu cn c 1 loi khng nguyn khc c gi l khng nguyn Rh (n c ci tn ny do

loi khng nguyn ny c xc nh ln u tin kh Rhesus). Hu ht nhng ngi Vit Nam

mang nhm mu Rh dng (Rh+), iu c ngha l h c mang khng nguyn Rh. Nhng

ngi mang nhm mu Rh m (Rh-) th khng mang khng nguyn Rh. Khng ging vi nhm

mu ABO, cc khng th chng li khng nguyn Rh khng c tm thy mt cch t nhin

trong mu. Vn duy nht ch tht s xy ra khi ngi mang nhm mu Rh- c truyn vo

c th mu c Rh+. Khi , c th ca h s phn ng li bng cch to ra khng th chng li

khng nguyn Rh. ln truyn mu k tip, nu vn tip tc c truyn mu c Rh+ th khng

th chng li Rh c to ra t ln truyn mu trc s tn cng mu c truyn vo.

BCH CU

Bch cu c rt t nu so vi hng cu, khong 4.000 n 11.000 mi millimet khi mu, chim

t hn 1% tng th tch mu. Mc d chim s lng t nh vy nhng bch cu li ng mt

vai tr quan trng trong h thng min dch ca c th. N gip c th phng th, chng li s

tn cng ca vi khun, virus, k sinh trng v t bo ung th. Ging nh hng cu, bch cu

cng c to thnh t ty xng (mt s bch cu c to ra t cc m lympho). Trong khi

hng cu phi i theo dng chy ca mu th bch cu khng nh vy m n c th len qua cc

vch ca cc mao mch i thng n nhng khu vc b nhim trng hoc b tn thng ca

c th.

KHNG NGUYN Rh V THAI KZ

Yu t Rh ng mt vai tr quan trng trong thai kz khi ph n c Rh- ang mang thai a b

c Rh+. Trong qu trnh mang thai, nhng vt t trn mng nhau gip m c th tip xc c

vi mu ca tr c Rh+ (mng nhau l 1 loi mng lt t cung, cc cht dinh dng v oxy di

chuyn t m i xuyn qua mng ny cung cp cho tr), khi c th ca m s to ra

khng th chng li khng nguyn Rh. ln mang thai k tip, nu con tip tc c nhm mu

Rh+ th khng th chng li Rh ca m s i qua mu ca con v tiu dit cc t bo hng cu

ca b.

phng nga iu ny, bc s s cho nhng thai ph c Rh- RhoGAM, mt loi khng th

chng li Rh trong vng 72 gi ca ln sinh u tin. RhoGAM s tiu dit nhng hng cu Rh+

i vo h tun hon ca m trc khi h min dch c thi gian to ra khng th.

C 5 loi t bo bch cu trong mu: bch cu a nhn trung tnh (neutrophil), bch cu i toan

(eosinophil), bch cu i kim (basophil), mono bo v lympho bo. Mi loi gi mt vai tr

khc nhau trong h thng phng th ca c th v c huy ng chng li nhng loi bnh

khc nhau. Chng hn nh trong nhng bnh nhim trng mn tnh (ko di) nh lao phi th

mono bo gia tng s lng. i vi bnh nhn b hen suyn v trong nhng t d ng th

bch cu i toan gia tng s lng.

Hnh nh i thc bo ( pha sau) v lympho bo ( pha trc)

Cc t bo bch cu xc nh c mc tiu cn n nh nhng loi ha cht c bit. Khi m

b nhim trng hoc tn thng, n s phng thch nhng cht ha hc ra cc m xung quanh

li ko nhng t bo bch cu thch hp n chin u chng li. Tin trnh ny c gi l

ha ng ng.

TIU CU

Tiu cu khng phi l mt t bo tht s ging nh hng cu v bch cu. Chng l nhng

mnh v nh c dng hnh a ca nhng t bo rt ln c gi l t bo nhn khng l

(megakaryocyte) nm trong ty xng. T bo nhn khng l b v ra to thnh khong 50

mnh nh hoc hn v sau nhanh chng hnh thnh mng tr thnh tiu cu. C khong

300.000 tiu cu mi millimet khi mu, chng gip kim sot chy mu trong mt qu trnh rt

phc tp c gi l cn bng ni mi.

Khi mch mu b tn thng gy chy mu, cc tiu cu bt u tin trnh ng mu bng cch

dnh vo ni tn thng ca mch mu. Trong lc , chng phng thch ra nhng cht ha hc

li ko cc tiu cu khc li. Chng my chc, cc tiu cu kt dnh li v hnh thnh mt nt

chn tm thi. Sau , tiu cu phng thch ra serotonin, mt loi ha cht lm cho mch mu

co tht v hp li lm gim lng mu chy ra bn ngoi qua vt thng. Trong lc cc hin

tng ny xy ra, m b tn thng phng thch ra 1 cht kt hp vi calci v nhng yu t

ng mu khc trong huyt tng hnh thnh cht hot ha prothrombin. Cht hot ha

ny chuyn dng prothrombin (l mt cht c trong huyt tng do gan sn xut) thnh

thrombin (l mt loi enzyme). Thrombin sau kt hp vi fibrinogen to ra nhng phn

t di v mnh c gi l fibrin. Cc phn t fibrin kt hp vi nhau hnh thnh mt ci li

bt gi cc hng cu v tiu cu lm nn cho khi mu ng.

H TUN HON HOT NG NH TH NO

Trong qu trnh hot ng lin tc ca mnh, tim bp trung bnh hn 100.000 ln mi ngy

tng mu i hng nghn dm trong cc mch mu nui sng tng t bo mt trong hng t

t bo ca c th. mi nht bp, tim tng i khong 74 milli lt mu. ngi ln, tim trung

bnh p khong 72 nht mi pht, nh vy mi pht c khong 5,3 lt mu c tng i, mi

gi l 318 lt, mi ngy l 7.631 lt mu c tng i. Trong lc tp th dc, con s ny c th

tng ln gp 5 ln.

CHU CHUYN TIM

Chu chuyn tim l mt chui nhng s kin xy ra ti tim trong mt nhp p hon chnh ca

n. Mi mt chu chuyn tim chim khong 0.8 giy. Trong thi gian ngn , mu i vo tim, di

chuyn qua cc bung tim, sau c tng i ra khp cc khu vc ca c th. Mi mt chu

chuyn tim c chia ra lm 2 th. Hai tm nh co khi hai tm tht dn v sau th 2 tm tht

s dn ra khi 2 tm nh co. Pha co, c bit l tm tht, c gi l th tm thu, pha dn c

gi l th tm trng. Chu chuyn tim bao gm th tm thu v th tm trng ca c tm nh ln

tm tht.

DOPING MU

tng cng sc do dai ca mnh trc mi cuc thi u, mt s vn ng vin dng n

mt k thut c gi l doping mu. Th thut ny c thc hin bng cch rt bt mt

lng hng cu i. Sau khi mu b rt i, c th s p ng li bng cch nhanh chng sn xut

ra nhng hng cu khc thay th cho lng hng cu b ly i. Sau , mt vi ngy trc

khi thi u, ngi ta s tim ngc li lng mu rt ra vo c th.

Hiu qu ca vic ny l to ra hng cu nhiu hn do lng oxy trong mu cng nhiu hn.

Doping mu c th lm tng kh nng ca vn ng vin ln 10%.

Tuy nhin, th thut ny khng nhng khng hp php m cn nguy him. N c th lm suy

yu dng tun hon cng nh gy ra triu chng ging nh cm cm. Do thay v h tr

thm cho kh nng ca vn ng vin th n li lm hn ch nhng kh nng .

Qu trnh ny khi u khi mu b kh oxy (mang mt lng oxy rt nh) quay tr v tm

nh phi qua tnh mch ch. Cng lc , mu c oxy ha di chuyn t phi n tm nh

tri qua 4 tnh mch phi. Van nh-tht m ra v khi dng mu chy vo cc tm nh n cng

chy mt cch b ng vo cc tm tht. Cc van bn nguyt ng li ngn mu khng chy

t tm tht ra ngoi cc ng mch. Khi cc tm tht y khong 70%, nt xoang s gi i mt

xung ng lan truyn qua tm nh n nt nh tht. Tm nh co bp v tng khong 30% lng

mu vo cc tm tht.

Nt nh tht lm cc xung ng chm li trong mt thi gian ngn gip tm nh c thi gian

hon thnh qu trnh co li ca mnh. Xung ng ny sau i qua b nh tht, cc nhnh v

mng Purkinje n mm tim. Qu trnh co li ca cc tm tht c khi u t v tr ny,

p lc trong cc tm tht c gia tng mt cch nhanh chng v cc van nh tht ng li (gy

ra ting "bm" nghe c bng ng nghe) ngn khng cho mu chy ngc tr v tm nh.

Khi p lc trong cc tm tht tng cao hn p lc trong mu cc ng mch ln xut pht t

tim, cc van bn nguyt s m ra v mu s c tng ra khi cc tm tht. Mu b kh oxy

tm tht phi c bm ln phi qua cc ng mch phi, mu c oxy ha s ri tm tht

tri i n nhng phn cn li ca c th qua ng mch ch.

Khi tm tht co (th tm thu), cc tm nh dn (tm trng) v c y mu tr li. Khi tt

cc mu c tng i khi tm tht, cc van bn nguyt s ng li (gy ra ting tc nghe

c qua ng nghe) ngn nga dng mu chy ngc tr v tim. Cc tm tht tr nn trng

rng v ng li trong mt thi gian ngn. Khi p lc trong tm nh tng vt qu p lc trong

tm tht, van nh tht s m ra v mu s chy vo tm tht bt u mt chu chuyn tim

mi.

Tm li, trong mt chu chuyn tim, na phn trn ca tim (cc tm nh) nhn mu v mt na

phn di (cc tm nh) bm mu. Na phn bn phi ca tim (nh phi v tht phi) nhn v

bm mu b kh oxy, na phn bn tri (nh tri v tht tri) nhn v bm mu c oxy

ha.

HUYT P

Khi tm tht co, n tng mu ra khi tim i n cc ng mch ln v n hi lm chng dn ra

khi mu chy qua. p lc ca mu chng li thnh trong ca cc mch mu c gi l huyt

p. p lc ny cn thit gip cho mu chy n khp ni trong c th v quay ngc v tim.

Huyt p ln nht nhng ng mch ln v gn tim nht. Do cc thnh mch c tnh n hi

nn cc ng mch c kh nng phn hi li v bo ton hu ht p lc ca mu khi n c

tng ra khi tim. Khi mu i n nhng mch mu t n hi hn - nhng tiu ng mch, sau

n mao mch, tiu tnh mch v tnh mch - huyt p s gim xung. Khi mu quay tr v

tm nh phi qua tnh mch ch, p lc gn nh bng 0.

Khi tim co v dn trong sut chu chuyn tim th huyt p cng tng v gim trong mi nhp p.

Huyt p tng cao hn trong th tm thu (tht tri co) v gim thp hn th tm trng (tht

tri gin).

Huyt p c o bng n v milimet thy ngn (mmHg) bng my o huyt p. Gi tr huyt

p ghi nhn c thng l c ly t ng mch cnh tay. p lc tm thu c ghi nhn

trc, sau mi n p lc tm trng. Trung bnh, mt ngi trng thnh tr tui c

huyt p o c vo khong 120 mmHg i vi huyt p tm thu v 80 mmHg i vi huyt

p tm trng (c vit l 120/80 v c c l "mi-hai-trn-tm"). Ty thuc vo tui

tc, gii tnh, cn nng, v nhng yu t khc, huyt p bnh thng c gi tr thay i t 90

n 135 mmHg i vi huyt p tm thu v 60 n 85 mmHg i vi huyt p tm trng. Bnh

thng th huyt p cng gia tng theo tui.

O HUYT P

Nhn vin y t o huyt p ca bnh nhn bng mt thit b c bit c gi l my o huyt

p (sphygmomanometer). Thit b ny bao gm mt vng bng cao su, mt ci bng dng

bm bng tay v mt my dng c gi tr huyt p.

Vng cao su c bao va kht xung quanh cnh tay ca bnh nhn ngay pha trn khuu tay.

Sau , ngi o huyt p s t ng nghe ln ng mch cnh tay mt trong ca cnh tay

ngay pha trn cng tay nghe nhp mch p.

Vng cao su c bm cng phng ln bng cch bp bng cho n khi dng mu chy vo

cnh tay b ngng li v khng cn nghe hay cm thy nhp mch p na. Sau p lc vng

cao su s c gii phng t t. Khi mt lng mu nh bt u chy qua c ng mch b

chn p ta s nghe thy c mt m nh qua ng nghe. p lc ca vng cao su c c vo

thi im nghe c ting ng u tin c ghi nhn l huyt p tm thu.

Khi p lc ca vng cao su c gii phng nhiu hn na, ting nhp p tr nn ln hn v

du hn. Khi ng mch khng cn b p na v mu chy t do th ting ng s bin mt. p

lc ca vng cao su ghi nhn c vo thi im ting nhp p cui cng nghe c c gi

l huyt p tm trng.

Hnh ty l mt khi m thn kinh nm u ca ty sng v sn ca s kim sot nhng c

ng ngoi chng hn nh th v nhp tim. trong hnh ty c 2 trung tm iu khin tim

mch l trung tm kch thch v trung tm c ch. Nhng trung tm ny gi nhng xung thn

kinh n tim iu ha nhp tim.

H thn kinh t ch l mt phn ca h thng thn kinh c nh hng n nhng c quan ni

tng nh tim, phi, d dy, v gan. Chc nng ca n l ngoi {, iu ny c ngha l nhng c

ng m n iu khin xy ra m khng cn c s can thip ca thc. H thn kinh t ch

c chia ra lm 2 phn: h giao cm v h ph giao cm. H ph giao cm hot ng ch yu

khi c th ang trng thi bnh thng v ngh ngi, h giao cm hot ng ch yu nhng

lc c th b stress hoc cn nng lng.

Trung tm kch thch hnh no gi mt xung thn kinh i theo nhng dy giao cm n tim

lm tng nhp tim v tng lc co bp. Trung tm c ch gi xung thn kinh i theo nhng

dy ph giao cm n tim lm gim nhp tim. Nhng trung tm ny hot ng p ng li

vi nhng thay i ca huyt p v nng oxy trong mu thng l do tp th dc, tng thn

nhit v stress v cm xc. Nhng thay i trn c nhn bit nh cc cm th quan nm trn

ng mch cnh v cung ng mch ch.

Cc cm th quan ng mch cnh nhn bit c s gim huyt p, nhng cm th quan

trn cung ng mch ch cm nhn c s gim nng oxy trong mu. C 2 loi cm th

quan ny gi nhng xung thn kinh i dc theo nhng dy cm gic n trung tm kch thch,

v trung tm ny s gi nhng xung thn kinh i dc cc dy thn kinh n nt xoang ca tim

lm tng nhp tim. Khi huyt p v nng oxy trong mu tr v mc bnh thng th trung

tm c ch s gi nhng xung thn kinh n nt xoang n lm chm nhp tim li v mc bnh

thng.

S TRAO I GIA CC MAO MCH V CC M CA C TH

Cc ng mch, tiu ng mch, tiu tnh mch v tnh mch ch c mt chc nng duy nht l

vn chuyn mu i t tim ra ngoi hay t ngoi tr v tim. S trao i cht - oxy, CO2, cht

dinh dng v cht thi - gia mu v dch k din ra qua cc mao mch. Nhng s di chuyn

ny thay i khc nhau trong 3 cch: khuych tn, lc v thm thu.

Khuych tn l hin tng cc phn t di chuyn t khu vc c nng cao hn (cha nhiu

phn t loi hn) n khu vc c nng thp hn (cha t phn t loi hn). Hin

tng khuyc tn xy ra v cc phn t c nng lng t do, c ngha l chng lun lun chuyn

ng. y l trng hp c bit ca nhng phn t kh vn chuyn ng nhanh hn nhng

phn t cht lng v cht rn. Oxy v kh carbonic di chuyn qua li gia mao mch v dch k

bng s khuych tn. Khi mu i qua mao mch, oxy c ch bi hemoglobin trong hng cu

c s lng ln hn nn di chuyn n dch k xung quanh c s lng oxy t hn c

cc t bo nhn ly. Ngc li, CO2 c nng nhiu hn trong dch k nn di chuyn vo cc

mao mch c chuyn i. S trao i kh gia mu v dch k c gi l s h hp ni ti

(internal respiration).

Hin tng lc l cch di chuyn ca nc v cc cht tan trong nc xuyn qua mng t khu

vc c p lc cao hn n khu vc c p lc thp hn. Khi mu i vo cc mao mch n c p

lc o c l 33 mmHg trong khi p lc ca dch k ch khong 2 mmHg. Do , thng qua

hin tng lc, huyt tng v cc cht dinh dng nh amino acid, glucose, v vitamin i

xuyn qua thnh cc mao mch n cc dch k xung quanh.

S thm thu l hin tng khuych tn ca nc i qua mng bn thm (l mt loi mng ch

cho php mt vi cht qua c m thi). N di chuyn t khu vc c nhiu hn n khu vc

c t hn. Lin quan trc tip n hin tng ny l p lc thm thu, l khuynh hng ca mt

dung dch k o nc i vo dung dch . Gi tr ca p lc thm thu c tnh bng lng

cht ha tan c trong dung dch. Nu lng cht ha tan c trong dung dch cng ln th lng

nc c trong dung dch cng nh. Dung dch c cha mt lng ln cc cht ha tan s c

p lc thm thu ln v nc s c khuynh hng b ko vo dung dch nhiu hn.

u tn tip gip vi tiu tnh mch ca cc mao mch, ngay trc khi chng kt hp li

to thnh cc tiu tnh mch, p lc thm thu cc mao mch cao hn dch k do s hin

din ca albumin v mt s phn t protein ln vn cn nm li nh mt cht ha tan trong

mu. Dch k c p lc thm thu thp hn v do n s b ko vo cc mao mch v c

mang i.

Hnh nh s thm thu: nc i t ni c nhiu n ni c t nc hn

S TRAO I CA MAO MCH TRONG PHI

Sau khi mu i ht cc m ca c th, trao i oxy v cht dinh dng ly CO2 v cc cht

b th n quay tr v tim. Mu b kh oxy tr v tm nh phi qua tnh mch ch, sau i

vo tht phi. Ti y n s c bm ln thn ng mch phi, sau thn ng mch phi

s chia ra lm 2 nhnh ng mch phi phi v ng mch phi tri mang mu b kh oxy

i vo mi bn phi.

Ti phi, cc ng mch tip tc chia nhnh ra thnh nhng ng mch nh hn ri sau

thnh nhng tiu ng mch nh hn na. Cui cng, nhng tiu ng mch nh nht s phn

nhnh ra thnh cc mao mch. Nhng mao mch phi ny bao xung quanh cc ph nang, l

nhng ti kh ca phi. S trao i oxy v kh CO2 ti phi xy ra xuyn qua thnh ca cc ph

nang v gn cc mao mch.

S trao i kh ny xy ra da trn nguyn tc khuch tn. Kh trong cc ph nang c nng

oxy cao. Mu trong cc mao mch phi c nng CO2 cao. Do , theo nguyn tc khuch

tn, oxy ti cc ph nang s di chuyn vo cc mao mch trong khi CO2 trong cc mao mch

s di chuyn ngc li vo cc ph nang.

Sau khi c oxy ha, mausex chy t cc mao mch sang cc tiu tnh mch, chng kt hp

vi nhau thnh nhng tnh mch ln dn. Cui cng, mu ri khi phi qua 2 tnh mch phi

ln v c mang n tm nh tri c bm ngc tr li vng tun hon h thng mt

ln na. S di chuyn ca mu t phi tr v tim l mt hin tng kh c bit trong c th v

y l ln duy nht m cc tnh mch li c mang mu c oxy ha.

VNG TUN HON GAN - TNH MCH CA

Mt vng tun hon c bit khc na l vng tun hon gan - tnh mch ca, mt nhnh ca

vng tun hon h thng. vng tun hon ny, mu i t cc c quan ca b my tiu ha v

t lch chy qua gan trc khi i thng v tim.

Cc mao mch dn mu n d dy, rut non, rut gi, ty v lch chy vo 2 tnh mch ln l

tnh mch mc treo trng trn v tnh mch lch. Hai tnh mch ny hp vi nhau thnh tnh

mch ca mang mu i vo trong gan.

Khi vo gan, tnh mch ca chia nhnh ra hnh thnh cc mao mch c gi l cc

xoang. Cc xoang ny ln hn nhng mao mch bnh thng khc. Thnh ca chng c tnh

thm cao hn, cho ph p cc protein v t bo mu i vo v ra d dng. y l tnh cht rt

quan trng v mu i vo gan t cc c quan thuc h tiu ha c cha mt lng ln cc cht

dinh dng.

Khi mu chy t t qua cc xoang trong gan, mt s cht dinh dng c ly ra khi mu v

cha trong gan c s dng sau hoc chuyn thnh nhng cht khc cn thit cho c th.

T cc xoang, mu chy vo cc tnh mch gan tri v phi, sau i i vo tnh mch ch di v

cui cng i vo tm nh phi.

t khi gp hin tng mu chy hon ton t h tiu ha n tim. Bnh thng th mu t cc

ng mch v cc mao mch v chy vo cc tnh mch. vng tun hon gan-tnh mch

ca khng c s tham gia ca ng mch m cc mao mch kt hp li to thnh cc tnh

mch, sau chia nh ra thnh cc mao mch ri kt hp thnh cc tnh mch tr li. Vng

tun hon ny l cn thit mu c th c gan iu chnh. Cc cht dinh dng c th

c bo qun hoc thay i v khi cc cht c th gy c (nh ru v thuc) c th

chuyn thnh nhng cht t gy hi hn trc khi mu tr v tim v phn cn li ca vng tun

hon.

2. SINH L MU

1. KHI LNG.

Mu l t chc lng, lu thng trong h tun hon. Trong 1 kg th trng, c 75 - 80ml mu. Tr

s sinh c 100ml mu /kg cn nng, sau khi lng mu gim dn. T 2 -3 tui tr i khi

lng mu li tng dn ln, ri gim dn cho n tui trng thnh th hng nh. Mt ngi

trng thnh, bnh thng mu chim 7 - 9% trng lng c th. Mt ngi nng 50kg c

khong 4 lt mu. Ngi ta c th xc nh khi lng mu chnh xc bng nhiu phng php

khc nhau: phng php tim cc cht c mu vo mu, cht ny t b lc ra khi thn, phn

hu nhanh v khng c hi hoc dng cc cht ng v phng x nh du hng cu.

Khi lng mu tng ln sau khi n, ung, khi mang thai, khi truyn dch... Khi lng mu gim

khi c th ra nhiu m hi, nn ma, a chy, chn thng c chy mu bn trong hoc bn

ngoi c th ... Nu khi lng mu tng ln trong c th, dch t mu s vo khong gian bo

ca da v cc m, sau nc c bi xut dn theo nc tiu. Nu khi lng mu gim

trong c th, dch t khong gian bo vo mu lm cho khi lng mu tng ln. Trong nhiu

trng hp mt mu cp din (mt mu cc tng ln, cc xng ln, mt mu ng ng

mch ...) khi lng mu b gim t ngt, c th khng c kh nng t b tr; nu khng cp

cu kp thi, c th s khng sng c.

2. THNH PHN.

Mu gm hai thnh phn: th hu hnh (huyt cu) v huyt tng. Cc th hu hnh ca mu

l hng cu, bch cu v tiu cu, chim 43 - 45% tng s mu, ch s ny c gi l

hematocrit. Hng cu l thnh phn chim ch yu trong th hu hnh. Huyt tng chim 55 -

57% tng s mu. Huyt tng cha nc, protein, cc cht in gii, cc hp cht hu c v

v c, cc hocmon, cc vitamin, cc cht trung gian ho hc, cc sn phm chuyn ho ... Huyt

tng cha ton b cc cht cn thit cho c th v ton b cc cht cn c thi ra ngoi.

Huyt tng b ly mt fibrinogen th c gi l huyt thanh.

3. CHC NNG SINH L[ CA MU.

Mu c rt nhiu chc nng , di y l nhng chc nng c bn ca mu:

3.1. Chc nng dinh dng.

Mu mang trong mnh ton b cc cht dinh dng nui c th. Cc cht dinh dng c

a t ngoi vo qua ng tiu ho. Ngoi ra bch cu cn vo lng ng tiu ho nhn cc

cht dinh dng theo kiu "m bo" v "thc bo", ri li vo lng mch mang thm mt phn

cc cht dinh dng cho mu.

3.2. Chc nng bo v.

Mu c kh nng bo v c th khi b nhim trng nh c ch thc bo, m bo v c ch

min dch dch th, min dch t bo. Mu cng c kh nng tham gia vo c ch t cm mu,

trnh mt mu cho c th khi b tn thng mch mu c chy mu.

3.3. Chc nng h hp.

Mu mang 0xy t phi ti t bo v m, ng thi mu mang cacbonic t t bo v m ti

phi.

3.4. Chc nng o thi.

Mu mang cc cht sau chuyn ho, cht c, cht l ti cc c quan o thi (thn, b my

tiu ho, phi, da ) thi ra ngoi.

3.5. Chc nng iu ho thn nhit.

Mu mang nhit phn "li" ca c th ra ngoi thi vo mi trng hoc gi nhit cho c

th nh c ch co mch da.

3.6. Chc nng iu ho cc chc phn c th.

Bng s iu ho tnh hng nh ni mi, mu tham gia vo iu ho ton b cc chc phn

c th bng c ch thn kinh v thn kinh - th dch.

4. C TNH CA MU.

Mu c tnh hng nh. Tnh hng nh ca mu c nh gi qua cc ch s sinh l, sinh ho

ca mu. Cc ch s ny, trong iu kin sinh l{ bnh thng l rt t thay i hoc ch thay i

trong mt phm vi rt hp. V vy chng c coi nh l mt hng s. Kim tra cc ch s sinh

l, sinh ho ca mu l mt vic lm v cng quan trng v rt cn thit nh gi nhng ri

lon chc nng ca c th.

3. RI LON LM SNG MU

1. Thiu mu.

Thiu mu l gim Hb trong mu di mc bnh thng. Theo W.H.O ngi b thiu mu l

ngi c hm lng Hb mu gim:

< 13gHb trong 100ml mu (i vi nam)

< 12g Hb trong 100ml mu (i vi n)

< 14g Hb trong 100ml mu (i vi tr s sinh)

Thiu mu l do mt mu, do mu b hu nhanh hn trong c th hoc do tu xng gim sn

xut.

- Thiu mu do mt mu cp tnh hoc mn tnh.

- Thiu mu do suy nhc tu v b nhim x, nhim c (cht c ho hc cng nghip, chin

tranh).

- Thiu mu do thiu acid folic, thiu vitamin B12 hoc thiu yu t ni v ct b d dy vim

teo d dy, vim lot d dy- t trng.

-Thiu mu do thiu st, do thiu dng.

- Thiu mu do thiu cc yu t kch thch tng sinh, tng trng hng cu erythropoietin (suy

thn, gan mn tnh).

- Thiu mu do tan mu, do i sng hng cu qu ngn. Mt s bnh ca hng cu do mng

hng cu km bn d v nh bnh thiu mu c hng cu hnh li lim, bnh thiu mu c

hng cu hnh cu (kch thc hng cu rt nh, hnh cu).

2. a hng cu.

- a hng cu th pht do sng vng ni cao, do suy tim, do bnh ng h hp... y l a

hng cu do thiu oxy cc m.

- a hng cu tht s do tu xng tng sn xut hng cu (c km theo tng bch cu v tiu

cu). Hu qu l qu ti chc nng tun hon, nht mu tng, ri lon tun hon mao mch.

4. SINH L CM MU V NG MU

1. CM MU.

Cm mu l mt qu trnh sinh l, sinh ha tng hp nhm chm dt hoc ngn cn s mt

mu ca c th khi mch mu b tn thng hoc b t. Cm mu c thc hin nh cc c

ch: co mch, s hnh thnh nt tiu cu, ng mu, co cc mu, tan cc mu ng v s pht

trin m x trong cc mu ng ng kn vt thng.

nh gi khi qut chc nng cm mu, cc nh lm sng thng s dng hai xt ngim: xc

nh thi gian chy mu (s b nh gi cc yu t ca thnh mch v tiu cu), xc inh thi

gian ng mu (s b nh gi cc yu t gy ng mu ca huyt tng). Thi gian mu chy

theo phng php ca Duke l 3 pht. Thi gian mu ng theo phng php ca Milian l 7

pht.

1.1. Co mch.

Ngay sau khi mch b tn thng, mch mu b co li do tnh n hi ca thnh mch. Co mch

cn c thc hin nh c ch thn kinh v thn kinh-th dch. Nhng kch thch gy au t

ni tn thng, nhng cht trung gian ho hc c gii phng khi au gy phn x co c trn

thnh mch. ng thi lc ny ti ni tn thng, tiu cu b v ra, gii phng serotonin gy co

mch ti ch.

1.2. S hnh thnh nt tiu cu.

Ti ni tn thng, t bo ni mc hoc thnh mch tn thng l si collagen, tiu cu

bm vo nhng ni ny v b hot ho. Khi tiu cu b hot ho, cc protein trong n c rt

mnh v gii phng ra cc yu t lm hot ho cc tiu cu bn cnh, lm cho chng dnh vo

nhau to nn nt tiu cu bt kn ch tn thng (nu l cc tn thng nh). Hng ngy c th

ta phi chu hng trm vt rch rt nh ni mao mch do sang chn. Nh c chc nng ny m

c th trnh c s chy mu mao mch.

1.3. S hnh thnh cc mu ng.

Tiu cu gii phng ra cc yu t gy co mch v gy ng mu, to ra cc mu ng b sung

cho nt tiu cu bt kn ch tn thng (nu l cc tn thng ln hn). ng mu pht

trin nhanh trong vng 1-2 pht. Nhng cht hot ho gy ng mu c gii phng do t

chc v mch mu b tn thng, nhng cht do tiu cu gii phng v nhng cht gy ng

mu ca huyt tng c hot ho, pht ng mt qu trnh ng mu. Nu vt thng

khng qu nng, sau 3-6 pht cc mu ng hnh thnh bt kn vt thng. Sau 20 pht n 1

gi, cc mu ng co li lm cho cc mu vng chc hn.

Sau khi cc mu ng hnh thnh, vi gi sau cc nguyn bo si xm nhp, bin cc mu ng

thnh m x trong 1-2 tun l, nu l cc mu ng nh v vt thng nh. Nu l vt thng

ln, tn thng rng, mu mt nhiu, c th khng t bo v c, cn phi c s can thip

kp thi.

2. NG MU.

Trong mu v trong cc m c cha khong 50 cht c nh hng ti qu trnh ng mu. Cc

cht kch thch qu trnh gy ng mu gi l cc cht gy ng mu. Cc cht li c ch qu

trnh gy ng mu gi l cc cht chng ng mu. Mu c ng hay khng ng l ph thuc

vo s cn bng gia cc cht gy ng mu v cc cht chng ng mu. Bnh thng mu

trong c th khng ng l do cht chng ng mu chim u th. Khi mu, mch mu b tn

thng, khi mu ly ra ngoi c th, cc cht gy ng mu c hot ho v tr nn u th,

ng mu c thc hin.

2.1. nh ngha.

ng mu l mt qu trnh chuyn mu th lng sang th c, m thc cht l chuyn

fibrinogen dng ha tan thnh fibrin dng khng ho tan.

2.2. C ch ng mu (cc giai on ca qu trnh ng mu).

ng mu c din ra theo mt c ch rt phc tp. y l mt qu trnh hot ho v hot

ng ca cc enzym vi mc ch l to ra fibrin. Thng thng ngi ta chia qu trnh ng

mu ra lm ba giai on:

Giai on hnh thnh phc hp prothrombinase.

Giai on hnh thnh thrombin.

Giai on hnh thnh fibrin.

2.2.1. S hnh thnh phc hp prothrombinase.

Khi ng cho c ch ng mu l s hnh thnh phc hp prothrombinase. y l mt c ch

rt phc tp (c l l phc tp nht ) v ko di nht ca qu trnh ng mu. Qu trnh c

xy ra khi c chn thng thnh mch v m, khi c chn thng mu, khi c s tip xc ca

mu vi t bo ni mc tn thng hoc vi si collagen ca mch mu, vi cc m khc ngoi

ni mc hoc vi bt kz vt l no.

S hnh thnh phc hp prothrombinase theo hai c ch ngoi sinh v ni sinh. C ch ngoi

sinh xut hin nu c chn thng thnh mch hoc cc m k cn. C ch ni sinh xut hin

nu c chn thng mu hoc mu ly ra ngoi c th t lng mch. Trong c hai c ch ni

sinh v ngoi sinh c mt lot protein huyt tng (c bit l a2-globulin) ng vai tr rt quan

trng, l cc yu t gy ng mu ca huyt tng. Hu ht cc yu t ny l cc enzym

dng khng hot ng. Khi chuyn thnh hot ng, chng gy ra cc phn ng ho sinh lin

tip nhau ca qu trnh ng mu. Cc yu t ny c k hiu bng ch s Lam phn bit

vi cc yu t ca tiu cu c k hiu bng ch s rp.

Yu t I: fibrinogen

Yu t II: prothrombin

Yu t III: thromboplastin ca m

Yu t IV: ion Ca++

Yu t V: proaccelerin

Yu t VII: proconvertin

Yu t VIII: globulin A chng a chy mu (antihemophilic globin-AHG).

Yu t IX: globulin B chng a chy mu (plasma thromboplastin component-PTC).

Yu t X: Stuart-Prower

Yu t XI: globulin C chng a chy mu (plasma thromboplastin antecedent-PTA).

Yu t XII: Hageman

Yu t XIII: n nh fibrin (fibrin stabilizing factor-FSF).

- S hnh thnh phc hp prothrombinase theo c ch ngoi sinh.

M b tn thng gii phng yu t III, phospholipid t mng t bo m. Yu t X c hot

ho (Xa) nh yu t III, yu t VIIa (yu t VII c hot ho nh yu t III), ion Ca++ v

phospholipid. S hnh thnh phc hp prothrombinase t yu t Xa c s tham gia ca yu t

Va (yu t V c hot ho nh thrombin), ion Ca++ v phospholipid. Yu t Va lm tng hot

tnh ca yu t Xa. Phospholipid ng vai tr l cht nn cn ion Ca++ lm cu ni gia cc yu

t. Thrombin trong trng hp ny c tc dng iu ho.

- S hnh thnhphc hp prothrombinase theo c ch ni sinh.

Mu b chn thng, mu tip xc vi collagen hoc b mt vt l th lm hot ho yu t XII v

gii phng phospholipid tiu cu. Yu t XIIa chuyn yu t XI thnh yu t XIa (c s tham gia

ca yu t Fletcher v Fitzgerald). Yu t XIa chuyn yu IX thnh yu t IXa (c s tham gia ca

yu t tiu cu). Yu t X c hot ho c s tham gia ca yu t VIIIa (yu t VIII c hot

nh thrombin), yu t IXa, ion Ca++ v phospholipid. S hnh thnh phc hp prothrombinase t

yu t Xa c s tham gia ca phospholipid, yu t Va (yu t V c hot ho nh thrombin) v

ion Ca++. S hnh thnh phc hp prothrombinase theo c ch ni sinh chm hn rt nhiu (1-6

pht) so vi c ch ngoi sinh (15 giy).

Prothrombinase c hnh thnh t c ch ni sinh hoc ngoi sinh hoc ng thi c hai c

ch ni sinh v ngoi sinh. iu ny chng t hot tnh ca prothrombinase l ph thuc vo s

hot ho ca cc yu t tham gia vo qu trnh ny.

2.2.2.S hnh thnh thrombin

Prothrombin l a2-globulin, do gan sn xut, c trng lng phn t 68700, nng trong mu

bnh thng l 15mg/100ml mu. Khi phc hp prothrombinase hnh thnh n s chuyn

prothrombin thnh thrombin. Giai on ny cng cn s c mt ca ion Ca++. S hnh thnh

thrombin t prothrombin l rt nhanh, c tnh bng vi giy.

2.2.3. S hnh thnh fibrin.

Fibrinogen l mt protein do gan sn xut, trng lng phn t 340000, nng trong mu

bnh thng l 100-700mg/100ml mu. Bnh thng fibrinogen rt kh vo dch k. Khi thnh

mch tng tnh thm (m b vim) th fibrinogen vo dch k v b ng li do cc yu t gy

ng mu cng vo dch k.

Thrombin sau khi c hnh thnh chuyn fibrinogen thnh fibrin n phn. Cc fibrin n

phn t trng hp thnh fibrin dng si. Mt mng li fibrin hnh thnh v c n nh

nh yu t XIII. Giai on ny cng c s tham gia ca ion Ca++. Cc t bo mu c gi li

trn li fibrin v to nn cc mu ng. Chnh mng li ny dnh vo v tr tn thng ca

thnh mch ngn cn s chy mu.

Bn cht ca mu ng l hnh thnh li fibrin t fibrinogen nh thrombin. Chnh v vy cc

nh ngoi khoa s dng thrombin (dng tm, gc hoc bt...) cm mu khi phu thut,

c bit l cm mu cc xng xp.

2.3. S co cc mu ng.

Sau khi cc mu ng hnh thnh, n bt co li v r ra huyt thanh (huyt tng b ly mt

fibrinogen th c gi l huyt thanh).

Tiu cu c vai tr quan trng cho s co cc mu ng. Tiu cu c tc dng gn cc si fibrin

li vi nhau v n nh vng chc fibrin. Tiu cu bm trn li fibrin, khi n co rt n lm cho

li fibrin co theo, ng thi vi s gii phng yu t 8 ca tiu cu lm cho cc mu ng co

cng mnh hn. Co cc mu ng cn c s tham gia ca thrombin, ion Ca++. Cc mu ng lc

ny rt bn vng, gi cho cc mp ca thnh mch tn thng kh p li gn nhau to iu kin

thun li cho lin vt thng.

2.4. S tan cc mu ng.

Trong huyt tng c pasminogen (profibrinolysin). Cc m tn thng, ni mc tn thng v

vi khun gii phng ra cht hot ho plasminogen. Khong mt ngy sau khi cc mu ng,

cht ny chuyn plasminogen thnh plasmin. Plasmin l mt enzym lm tiu fibrin v c

fibrinogen lm tan cc mu. V l do ny m c th gy ra chy mu th pht rt nguy him, cn

phi c phng. Ti vim, nu vi khun lm tiu fibrin i th c th s lm cho vi khun

lan rng v hng ro fibrin bo v b ph v. Song cng nh c ch ny m trong c th c

hin tng t tiu fibrin lm khai thng nhiu mch mu nh b tc nghn.

5. CU TO - CHC NNG CA HNG CU

I. CU TO

1. HNH DNG V KCH THC.

Hng cu trng thnh, lu thng trong mu l t bo khng c nhn. iu kin t nhin, n

c hnh a lm hai mt, ng knh khong 7,2mm, b dy ngoi vi l 2,2mm, trung tm l

1mm

Th tch mt hng cu l 83mm3 (83femtolit). Nh c tnh n hi tt m hng cu d dng

thay i hnh dng khi i qua cc mao mch. Din tch b mt hng cu ln (do c hai mt lm),

v vy khi hng cu bin dng mng hng cu khng b cng v v ra. Nu tnh din tch ton b

mng hng cu trong c th cng li, c th ln n 3000m2.

2. THNH PHN.

T l thnh phn ca hng cu

% Cc thnh phn

67,00 Nc

28,00 Hemoglobin

0,30 Lipid cc loi (lecitin, cholesterol)

2,00 Nhng cht khc c cha nit (enzym, protein,

glutation)

0,02 Ur

1,20 Cc cht v c (K+)

Hng cu c mt cu trc c bit vi nhiu thnh phn khc nhau. N gm mt nn do protein

v lipid to nn. a s lipid u kt hp vi protein to thnh lipoprotein. Trong nn cn c

glucose, clorua, phosphat... Nn v mng chim 2 -5% trng lng hng cu. Gia cc mt ca

nn c hemoglobin. Hai thnh phn quan trng nht ca hng cu c nghin cu nhiu l

mng hng cu v hemoglobin. Mng hng cu mang nhiu khng nguyn nhm mu.

Hemoglobin l thnh phn quan trng trong s vn chuyn kh ca mu.

3. S LNG.

Ngi trng thnh, mu ngoi vi c 3,8 x 1012 hng cu/lt (i vi n); 4,2 x1012 hng

cu/lt (i vi nam). Tr mi sinh, ngy u s lng hng cu rt cao (5,0 x1012 hng

cu/lt). Sau , do hin tng tan mu, s lng hng cu gim dn. Tr em di 15 tui c s

lng hng cu thp hn ngi trng thnh 0,1 - 0,2 x 1012 hng cu/lt. S lng hng cu

n nh tui trng thnh.

S lng hng cu tng ln sau ba n, khi lao ng th lc, sng trn ni cao 700 - 1000m,

khi ra nhiu m hi, i nhiu, a chy, bng mt huyt tng, trong bnh a hng cu, bnh

tim bm sinh.... S lng hng cu gim lc ng, khi ung nhiu nc, cui kz hnh kinh, sau

, i lu ngy, ni c phn p oxy cao, cc loi bnh thiu mu, suy tu, nhim c, chy

mu trong, chy mu do vt thng...

4. QU TRNH SINH HNG CU

4.1. Ngun gc v cc giai on pht trin ca hng cu

Nhng tun u ca thai nhi hng cu c nhn c l thai gia sn xut. T thng th hai tr

i gan, lch, sau l hch bch huyt cng sn xut ra hng cu c nhn. T thng th 5 ca

kz pht trin thai, tu xng bt u sn xut hng cu v t tr i, tu xng l ni duy

nht sinh ra hng cu. Sau tui 20 cc tu xng di b m ho, cn tu xng xp nh xng

sng, xng sn, xng c, xng chu sn xut hng cu. V vy tui gi d b thiu mu

hn.

T bo tu xng l t bo gc vn nng c kh nng duy tr ngun cung cp t bo gc v pht

trin thnh t bo gc bit ho to ra cc dng khc nhau ca t bo mu (theo thuyt mt

ngun gc). T bo gc bit ho sinh ra hng cu c gi l n v to cm ca dng hng

cu: C.F.U.E (Colony forming unit erythrocyt). Sau cc t bo dng hng cu tri qua cc giai

on sau y.

Tin nguyn hng cu (proerythoblast)

Nguyn hng cu a kim( normoblast a kim) Nguyn hng cu a sc (normoblast a

sc) Nguyn hng cu (normoblast) Hng cu li (reficulocyt) Hng cu trng thnh

(erythrocyt)

Nhn ca nguyn hng cu mt i khi nng hemoglobin trong bo tng cao > 34%. Hng

cu chnh thc khng c nhn xuyn mch ri b tu xng vo h tun hon chung. Hng cu

li cng c kh nng vo mu nh hng cu trng thnh nhng t l rt thp ch chim 1%

tng s lng hng cu mu ngoi vi, khong 1-2 ngy sau hng cu li tr thnh hng cu

trng thnh. Hng cu sng trong mu khong 120 ngy (ngi da trng), gn 120 ngy

(ngi Vit).

H thng enzym ni bo hng cu lun lun tng hp ATP t glucose duy tr tnh n hi

ca mng t bo, duy tr vn chuyn ion qua mng, gi cho st lun lun c ho tr 2, ng thi

ngn cn s oxy ho protein trong hng cu. Trong qu trnh sng, h thng enzym gim dn,

hng cu gi ci, mng hng cu km bn v d v.

Mt phn hng cu t hu trong mu, cn i b phn hng cu b hu trong t chc vng - ni

m ca lch, gan, tu xng. Hemoglobin c gii phng ra b thc bo ngay bi cc i thc

bo lch, gan, tu xng. i thc bo gii phng st vo mu v n c vn chuyn di

dng ferritin. Phn porphyrin ca hem trong i thc bo c chuyn thnh sc t bilirubin

gii phng vo mu, ri qua gan bi tit theo mt.

4.2.Cc nguyn liu cn thit cho qu trnh sinh hng cu

to thnh hng cu, trong c th c hai qu trnh song song: s to thnh t bo hng cu

v s tng hp hemoglobin. y l nhng qu trnh rt phc tp, i hi nhiu nguyn liu nh

protein, cholin, thymidin, acid nicotinic, thiamin, pyridoxin, acid folic, vitamin B12, Fe++, nhiu

enzym v cht xc tc cho qu trnh tng hp ny.

Vitamin B12 v acid folic rt cn cho qu trnh tng hp thymidintriphosphat, mt trong nhng

thnh phn quan trng ca DNA. Thiu vitamin B12 v acid folic s lm gim DNA, t bo s

khng phn chia v khng trng thnh c.Lc ny cc nguyn hng cu trong tu xng c

kch thc ln hn bnh thng, c gi l nguyn bo khng l. T bo to ra l v lng DNA

khng nhng lng RNA li tng dn ln hn bnh thng, t bo tng tng hp

hemoglobin hn v cc bo quan cng nhiu hn. Cc hng cu trng thnh s c hnh bu

dc khng u, mng mng hn v i sng s ngn hn (ch bng 1/3 - 1/2 thi gian ca hng

cu bnh thng).

Vitamin B12 qua ng tiu ho kt hp vi yu t ni (t bo vin tuyn d dy bi tit).

Phc hp ny gn vo receptor mng t bo nim mc hi trng v vitamin B12 c hp thu

theo c ch m bo. Vitamin B12 vo mu, d tr gan. Nhu cu vitamin B12 l 1 - 3 mg/24h.

Trong khi s d tr vitamin B12 ca gan c th gp 1000 ln nhu cu ca c th trong mt

ngy.

Thnh phn th hai khng km phn quan trng l st. St c hp thu theo ng tiu ho

vo mu. Trong mu, st c kt hp vi mt globulin l apotransferrin to thnh

transferrin vn chuyn trong huyt tng (v st lin kt vi globulin rt lng lo). St c vn

chuyn ti cc m c bit: t chc vng - ni m v gan. Ti y, st c gii phng ra v

c t bo hp thu.

Trong bo tng, st kt hp vi mt protein l apoferritin to thnh ferritin l dng d tr

st. Mt lng nh st c d tr dng hemosiderin trong t bo. c tnh duy nht ca

transferrin l n gn rt mnh vi receptor mng t bo nguyn hng cu. Trong t bo,

transferrin gii phng st vo ty lp th. Ti y din ra qu trnh tng hp hem. Mi ngy mt

ngi trng thnh cn 1mg st. Ph n cn st nhiu gp i so vi nam gii v b mt mu

qua mu kinh nguyt. St b thi hng ngy qua phn v m hi.

St c hp thu rut nh apoferritin do gan sn xut, bi tit theo mt vo t trng.

Apoferritin gn vi st t do hoc vi st ca hemoglobin, myoglobin to thnh

transferrin.Transferrin gn vo receptor t bo nim mc rut, ri vo mu. St c hp thu

rt chm v rt t, mc d st c n vo theo thc n l kh nhiu. Khi apoferritin trong c

th bo ho st th transferrin khng gii phng st cho cc m v cng khng nhn st t rut,

hp thu st b ngng li.

Khi c th tha st, gan gim sn xut apoferritin lm cho apoferritin trong mu v mt gim v

cng lm gim hp thu st. Trong trng hp n qu nhiu st, st vo mu nhiu dn n lng

ng hemosiderin trong cc t bo vng - ni m, gy c hi cho t bo ny.

4.3. S iu ho qu trnh sinh hng cu

S lng hng cu mu ngoi vi c iu ho hng nh nhm cung cp oxy cho t bo

hot ng. S tng trng v sinh sn ca cc t bo gc c kim sot bi cc protein kch

thch tng trng, v d nh interleukin 3.

Cc t bo gc bit ho n lt mnh li chu s kch thch tng trng ca cc cht gy bit

ho, m cc cht ny li c rt nhiu c quan nh thn, gan... sn xut khi chng b thiu

oxy.

Bnh nhn b thiu mu do mt mu, b gim chc nng tu xng khi b chiu x, nhng ngi

sng vng ni cao c nng oxy trong khng kh thp hn bnh thng, bnh nhn b suy

tim, cc bnh v phi c gim trao i kh phi... u gy ra thiu oxy cc m lm cho qu

trnh oxy ho cc m b gim i.

Khi cc m b thiu oxy chng sn xut ra erythropoietin. Erythropoietin l mt glucoprotein c

TLPT l 34000. Bnh thng 80-90% erythropoietin l do thn sn xut, cn li l do gan sn

xut. Mt s m khc cng sn xut erythropoietin, nhng khng ng k. V vy chng ta c

th gp bnh nhn thiu mu do suy thn mn tnh. Khi thn v gan thiu oxy, erythropoietin

s c sn xut sau vi pht hoc sau vi gi.

Erythropoietin do thn sn xut dng cha hot ng gi l erythogenin. Nh kt hp vi

mt globulin (do gan sn xut) erythogenin chuyn thnh erythropoietin hot ng.

Erythropoietin c tc dng: kch thch qu trnh chuyn C.P.U.E thnh tin nguyn hng cu v

kch thch chuyn nhanh cc hng cu non thnh hng cu trng thnh.

5. SC BN HNG CU

Mng hng cu l mt mng bn thm. Nc c th qua mng hng cu khi p xut thm thu

bn trong v bn ngoi hng cu khc nhau. Ngi ta xc nh sc bn hng cu bng dung

dch mui NaCl nhc trng c nng khc nhau t 0,02% mt ( phng php Hamberger).

Hng cu trong dung dch mui NaCl nhc trng b trng to ln v v ra do nc t dung

dch mui vo trong hng cu.Khi hng cu v, hemoglobin gii phng vo dung dch v lm

cho n c mu hng. Mt s hng cu bt u v trong dung dch mui NaCl nhc trng

0,44%. Nng mui NaCl 0,44% c gi l sc bn ti thiu ca hng cu. Ton b hng cu

v ht trong dung dch NaCl nhc trng 0,34%. Nng mui NaCl 0,34% c gi l sc

bn ti a ca hng cu.

Sc bn ca hng cu gim trong bnh vng da hu huyt, tng ln sau ct lch.

6. TC LNG HNG CU

Mu c chng ng, t trong ng nghim, hng cu lng xung di, huyt tng ni ln

trn. iu xy ra l do t trng ca hng cu (1,097) cao hn t trng ca huyt tng

(1,028). Khi c qu trnh vim din ra trong c th lm hm lng cc protein mu thay i, cn

bng in tch protein huyt tng thay i, in tch mng hng cu cng b bin i theo,

hng cu d dnh li vi nhau hn v lm cho n lng nhanh hn.

Nh vy tc lng mu cng cao th qu trnh vim ang din ra trong c th cng mnh. Ch

s tc lng hng cu l chiu cao ct huyt tng tnh bng mm trong 1h, 2h v 24h.

7. HEMOGLOBIN

7.1. Cu trc ca Hemoglobin.

Hemoglobin (Hb) l 1 protein mu, phc tp thuc nhm chromoproteid mu , c nhm

ngoi l hem. Hb l thnh phn ch yu ca hng cu, chim 28% v tng ng vi 14,6g trong

100 ml mu. TLPT ca Hb l 64.458.

Hb gm 2 phn: hem v globin. Mi phn t Hb c 4 hem v 1 globin. N c to thnh t 4

di n v. Mi di n v l 1 hem kt hp vi globin.

Globin c cu trc l cc chui polypeptid. ngi ln, 4 chui polypeptid ging nhau tng i

mt: 2 chui a v 2 chui b. Cc di n v lin kt vi nhau bng lin kt yu: lin kt ion, lin

kt hydro, to nn cu trc bc 4 ca phn t Hb (hnh 3.2). chui polypeptid ca mi di

n v c 1 hc cha hem. Trung tm ca phn t Hb c 1 hc rng gi l hc trung tm (hnh

3.3). Hc trung tm tip nhn phn t 2,3 diphosphoglycerat (2,3 DPG) v s kt hp ca hc

trung tm vi 2,3 DPG c vai tr iu ho i lc ca Hb vi 0xy.

Thnh phn th 2 ca Hb l hem. Sc t hem thuc loi porphyrin l nhng cht c kh nng

kt hp vi nguyn t kim loi. Hem ngi l porotophyrin IX kt hp vi Fe++. Hem c 4

nhn pyrol lin kt vi nhau bng cu ni menten (-CH=). Vng porphyrin c gn cc gc

metyl (-CH3) v tr 1, 3, 5, 8; cc gc vinyl (-CH=CH2) v tr 2,4; cc gc propionyl (-CH2 - CH2 -

C00H) v tr 6,7. Fe++ gn vi nh pha trong ca nhn pyrol bng hai lin kt ng ho tr v

hai lin kt phi tr v vi globin qua gc histidin (hnh 3.4).

Porphyrin l ph bin trong th gii sinh vt. Porphyrin kt hp vi Mg++ to thnh cht dip

lc ca thc vt.

Hem c th kt hp vi nhiu cht khc nhau. Nu hem kt hp vi globin th to thnh Hb.

Nu hem kt hp vi albumin, NH3, pyridin, nicotin... to nn cht gi l hemochromogen. Hem

phn ng vi NaCl trong mi trng acid to ra chloruahem (hemin). Phn ng ny c s

dng trong php y.

7.2 Cc loi hemoglobin ngi.

Hemogobin khc nhau phn cu to globin. Hb ca thai nhi l HbF. Globin ca HbF gm hai

chui a v hai chui g. Hb ca ngi ln l HbA. Globin ca HbA gm hai chui a v hai chui b

(v tr th 3 ca chui b l glutamin c thay bng threonin chui g). Hb ca bnh nhn mc

bnh thiu mu c hng cu hnh li lim l HbS (HbB) v tr th 6 ca chui b l valin c

thay bng glutamin. Loi hng cu ny rt d v khi qua mao mch nh. HbC v HbD l cc Hb

bnh thng gp mt s chng tc ngi Chu Phi.

C nhiu phng php nh lng Hb, k c cc phng php khng chy mu. Bnh thng

ngi Vit c Hb l 14,6g (i vi nam) v 13,3g (i vi n) trong 100ml mu. m s lng

hng cu v nh lng Hb l nhng xt nghim quan trng trong nh gi s thiu mu, thiu

mu ng sc (gi tr hng cu =1), thiu mu u sc (gi tr hng cu >1) v thiu mu nhc

sc (gi tr hng cu

Mt khc C02 m sau khi khuych tn vo trong hng cu th ti y din ra qu trnh C02 +

H20 H2C03 nh men xc tc carboanhydrase (men ny c nhiu trong hng cu). Sau H2C03

phn ly H+ + HC03- . Nh hiu ng Hamburger m HC03

- c khuych tn rt nhiu t trong

hng cu chuyn sang huyt tng to ra dng vn chuyn C02 quan trng nht ca mu

(C02 c vn chuyn di dng HC03- ). Nh vy hng cu ng vai tr quan trng bc

nht trong s vn chuyn C02 dng HC03- ca huyt tng.

2. Chc nng iu ho cn bng acid - base ca mu.

Chc nng ny do h m hemoglobinat m nhim. ng thi vi h m ca Hb, hng cu

cn to ra HC03- trong qa trnh vn chuyn C02, nn n to ra h m bicarbonat

HC03/H2C03, h m quan trng nht ca mu.

3. Chc nng to nht ca mu.

Hng cu l thnh phn ch yu to nht ca mu, nh nht m tc tun hon, nht

l tun hon mao mch, hng nh. Tc tun hon hng nh l iu kin thun li cho s

trao i vt cht gia t bo v mu. Khi nht ca mu thay i s gy ra thay i tc

tun hon v lm ri lon trao i vt cht ca t bo.

6. TIU CU

Trong tu xng c nhng t bo nhn khng l (40-100mm). Cc t bo ny c bit ho t

t bo gc vn nng.

T bo c nhn rt to, nhiu thuz, a dng vi nhim sc th phn b khng u. Bo tng

nhiu, mu nht, c nhiu ht rt nh mu xanh l. T bo nhn khng l cho gi tc di

chuyn. Cc gi tc ny b teo li, tch ra, t on thnh tiu cu lu thng trong mu. Nh

vy, tiu cu (thrombocyt) l mt phn bo tng ca t bo nhn khng l, l mt t bo

khng hon chnh, khng c nhn, rt a dng, bo tng tm nht c ht mu xanh, rt kh

m v d v khi ly ra khi c th

Tiu cu c kch thc 2-4mm, th tch 7-8mm3. Bnh thng c 150-300 x 109 tiu cu

trong 1 lt mu ngoi vi.

Tiu cu c cu trc mng glycoprotein, lp ny ngn cn tiu cu dnh vo ni mc nhng li

d dnh vo ni thnh mch tn thng c cht collagen l ra. Mng tiu cu cng rt d dnh

vo cc vt l. Khi bm vo vt l, chng li c th t bm vo nhau thnh tng m. Tiu cu

cha actomyosin, thromstbohenin nn tiu cu c kh nng co rt. Tiu cu co rt mnh s b

v ra v gii phng serotonin gy co mch, cc phospholipid v cc yu t gy ng mu tham

gia vo qu trnh gy ng mu.

- Yu t 1 l yu t c kh nng chuyn prothrombin thnh thrombin. V bn cht yu t 1 gn

ging yu t V ca huyt tng.

- Yu t 2 l yu t c tc dng y nhanh fibrinogen thnh fibrin khi c mt ca thrombin.

- Yu t 3 l mt phospholipid c hot tnh ca thromboplastin.

- Yu t 4 l yu t c hot tnh ca antiheparin to iu kin thun li cho giai on u ca

qu trnh ng mu.

- Yu t 5 l serotonin c kh nng gy co mch v c kh nng lm mu ng ti ch.

- Yu t 6 l mt protein c tc dng lm dy thnh mch v lm gim tnh thm thnh mch.

- Yu t 7 l antifibrinolysin, cht c tc dng ngn cn phn ng lm tan cc mu.

- Yu t 8 retractozym l mt yu t c tc dng lm co cc mu ng.

- Yu t 9 l mt cht lm n nh fibrin.

Vi c im chc nng trn y, tiu cu tham gia vo qu trnh cm mu, c xem nh

l mt hng ro bo v s mt mu. Tiu cu cng c kh nng gn ln vi khun to iu kin

thun li cho qu trnh thc bo c d dng. Ngoi ra tiu cu cn c tc dng khc na nh

lm h huyt p, chc nng min dch v chc nng sn xut cc enzym hu protein.

S sn xut tiu cu c iu ho bng s lng tiu cu nh c ch do cc yu t trong

huyt tng kim sot. Tiu cu b tiu dit lch. i sng tiu cu cha c nghin cu

y , ngi ta cho rng n sng trong mu khong 9-11 ngy.

S lng tiu cu tng ln khi lao ng, khi n ung, khi b chy mu, bnh a sinh mn tnh th

tu bo, bnh Hodgkin, bnh Vaquez. S lng tiu cu gim trong nhim c, nhim x, xut

huyt di da, nim mc, suy tu, bnh Biermer, bnh Werlhoff.

7. BCH CU

1. HNH DNG V S LNG.

Bch cu l cc t bo c nhn, hnh dng v kch thc rt khc nhau tuz tng loi. Bch cu

khng phi ch lu thng trong mu, m n cn c mt nhiu ni trong c th: bch huyt,

dch no tu, hch bch huyt, cc t chc lin kt...

Thnh phn bch cu rt phc tp, gm nhiu cht hu c v v c. Bo tng ca bch cu

cha nhiu st, calci, lipid (cholesterol, triglycerid v acid bo). Cc lipid ny lin quan ti vai tr

chng nhim trng ca bch cu. Bch cu cha nhiu lipid c xem nh tin lng tt chng

nhim trng (Boyd,1973). trong bch cu cn c nhiu acid ascorbic, ht glycogen. Ht glycogen

nhiu ln trong qu trnh tiu ho v mc bnh i tho ng. Bch cu c mt h thng

enzym rt phong ph (oxydase, peroxydase, catalase, lipase, amylase) v mt s cht dit

khun.

Trn mng t bo bch cu c rt nhiu th th lin quan ti chc nng ca bch cu. Da vo

cc th th ny, nh cc k thut hin i, ta c th phn loi c bch cu v theo di cc

giai on pht trin ca bch cu.

Trn b mt lympho bo c h thng khng nguyn ph hp t chc. Mc d mt s khng

nguyn c mt trn t bo ca nhiu m, nhng chng li b pht hin d dng trn lympho

bo. Do tt c khng nguyn ph hp t chc ch yu ca ngi c k hiu l HLA

(humanlymphocyt antigen). Tt c HLA hp thnh h thng khng nguyn ph hp t chc ca

ngi, cn gi l h thng HLA, chia thnh 5 nhm. Nhm HLA-A, nhm HLA-B, nhm HLA-C,

nhm HLA-D v nhm HLA-DR. Di cc nhm ny c rt nhiu phn nhm c t tn. H

thng khng nguyn HLA di truyn v rt c { ngha trong p ng min dch thi ghp.

Trong 1lt mu ngoi vi c 7,0 x 109 bch cu (i vi nam) 6,2 x109 bch cu (i vi n), nhn

chung vo khong 5,0 x 109 n 9,0 x 109 bch cu (i vi ngi trng thnh). Tr s sinh c

s lng bch cu rt cao: 20,0 x109 bch cu/1lt mu ngoi vi. Lc mt tui cn 10,0 x

109 bch cu/1lit mu. T 12 tui tr i s lng bch cu tr v n nh bng ngi trng

thnh.

S lng bch cu tng ln khi n ung, khi lao ng th lc, thng cui ca thi kz mang thai,

sau khi . c bit s lng bch cu tng ln khi nhim khun, bnh bch cu. Mt s

hormon v mt s tinh cht m cng lm tng s lng bch cu nh: hormon tuyn gip,

adrenalin, estrogen, tinh cht gan, tinh cht lch, tu xng. S lng bch cu gim khi b

lnh, khi b i, khi gi yu, suy nhc tu, nhim virus, nhim c, nhim trng qu nng, hoc

iu tr bng cc hormon corticoid, insulin ko di...

2. PHN LOI BCH CU.

V mt i th, vi k thut kinh in, da vo hnh dng, kch thc t bo, hnh dng nhn,

s bt mu ca ht trong bo tng. Ngy nay nh k thut hin i cn pht hin c cc

th th b mt t bo bch cu v.v...; ngi ta c th phn loi bch cu thnh bch cu ht

(bch cu a nhn) v bch cu khng ht (bch cu n nhn). Bch cu a nhn c chia

lm 3 loi: trung tnh, a acid v base. Bch cu n nhn c chia lm 2 loi: monocyt v

lymphocyt. ngi bnh thng, t l cc bch cu trong mu ngoi vi nh sau:

Bch cu ht a acid (E): 2,3%

Bch cu ht a base (B): 0,4%

Bch cu monocyt (M) : 5,3%

Bch cu ht trung tnh (N): 62,0%

Bch cu lymphocyt (L): 30,0%

Cc nh lm sng thng gi t l % cc loi bch cu mu ngoi vi l cng thc bch cu ph

thng. Cng thc thay i khi n ung, khi lao ng, khi c kinh nguyt, khi c thai trn 4 thng,

khi . Tr s sinh c ti 70% l bch cu a nhn, t thng th 3 tr i ch cn 35% l cc bch

cu a nhn (lc ny ch yu l lympho bo). Cng thc bch cu dn n nh n sau tui dy

th mi bng ngi trng thnh.

Ngy nay nh k thut cao chng ta c th phn loi bch cu mt cch chi tit hn vi mc

ch tm hiu chc nng ca tng loi bch cu phc v cho nghin cu khoa hc, chn on v

iu tr. Tuy vy vic xc nh cng thc bch cu ph thng v s lng bch cu vn c coi

l xt nghim thng quy ca bnh vin v n vn cn gi tr thc tin. ng thi vi xc nh

gi tr tng i (l t l % ca tng bch cu), cc nh lm sng cn xc nh gi tr tuyt i

(s lng tng loi bch cu c trong 1lt mu). Ch s ny rt cn cho s tin lng bnh.

Bch cu a nhn trung tnh (N) tng >70% trong cc trng hp nhim khun cp, qu trnh

lm m, vim tnh mch, nghn mch, nhi mu c tim, nhi mu phi. N cn tng trong co

git ng kinh, a protein vo trong c th, chy mu phc mc nh. ng thi vi N tng cn

c bch cu a (stab) tng.

- Bch cu a nhn trung tnh gim

Dng monocyt: t bo gc vn nng pht trin qua nhiu giai on bit ho thnh monocyt.

Cha bit chnh xc thi gian sng ca bch cu trong mu l bao lu v bch cu c mt khp

mi ni. Bch cu vo cc c quan ri t cc c quan quay tr li mu. Thi gian bch cu c

mt trong mu chng qua l thi gian vn chuyn bch cu t ni sn xut n ni s dng. V

vy thi gian sng ca bch cu trong mu l rt ngn.

Nu ngng sn xut bch cu t ngt (bng cch chiu tia g) trong 3 n 6 ngy u mu

ngoi vi khng cn bch cu a nhn trung tnh. Thi gian bch cu sng trong mu khang 4-5

ngy. Thi gian bch cu sng c trong v ngoi mch khong 8-12 ngy. Thi gian bch cu tn

ti trong tu xng khong 4-8 gi. Kh c th xc nh chnh xc thi gian sng ca bch cu

monocyt v n lun lun qua li gia cc m. Thi gian lu thng ca monocyt trong mu

khong 10-20 gi. Thi gian sng ca monocyt trong cc vim di hn bch cu a nhn trung

tnh. Lympho bo vo h tun hon lin tc qua ng ngc. S lng lympho bo trong ng ngc

vo h tun hon chung trong 24 gi thng l gp nhiu ln s lng lympho bo mu mt

thi im. iu chng t thi gian lympho bo sng trong mu l rt ngn (24h). Bch cu

lympho t c quan bch huyt vo mu, t mu ti m, t m li vo c quan bch huyt, ri

li vo mu... chu kz c th din ra lin tc.

Bch cu b tiu dit khp mi ni trong c th khi b gi ci, nhng ch yu l trong lng ng

tiu ho, phi v lch. Bch cu (c bit l cc i thc bo, bch cu ht trung tnh) b tiu

dit cc vim, cc vng v cc din ca c th d b vi khun t nhp nh da, phi, nim

mc.

4. C TNH CA BCH CU.

Bch cu c nhng c tnh chung sau y:

4.1. Xuyn mch.

Bch cu M v N c kh nng thay i hnh dng, xuyn qua vch gia cc t bo ti nhng

ni cn thit.

4.2. Chuyn ng theo kiu a mip.

Bch cu M v N c kh nng chuyn ng bng chn gi (theo kiu amip) vi tc :

40mm/min.

4.3. Ho ng ng v nhit ng ng

C mt s cht do m vim sn xut, do vi khun to ra hoc nhng cht ho hc a t ngoi

vo c th thu ht bch cu ti (ho ng ng dng tnh) hoc xua ui bch cu ra xa hn

(ho ng ng m tnh). Tng t, vi nhit cng nh vy, bch cu cng c nhit ng ng

dng tnh v m tnh. Cc c tnh ny ch yu l ca bch cu M v N.

4.4. Thc bo.

Bch cu M v N c kh nng thc bo, m bo. Nhng iu kin thun li cho thc bo l:

+ B mt ca vt rng v x x.

+ Khng c v bc. Cc cht t nhin trong c th c v bc l protein, cc cht ny y t bo

thc bo ra xa nn kh thc bo. Cc m cht, cc vt l khng c v bc v thng tch in

rt mnh nn chng d b thc bo.

+ Qu trnh opsonin ho. Cc khng th (c sn xut trong qu trnh min dch) gn vo

mng t bo vi khun lm cho vi khun d b thc bo.

S thc bo c thc hin nh sau:

Bch cu tip cn vt l, phng chn gi bao vy vt l, to thnh mt ti kn cha vt l. Ti

ny xm nhp vo trong t bo, tch khi mng t bo to ra mt ti thc bo tri t do trong

bo tng. Ti thc bo tip cn lysosom v cc ht khc trong bo tng v xut hin hin

tng ho mng. Cc enzym tiu ho v cc tc nhn git vi khun c trt vo ti thc bo

x l vt l. Ti thc bo tr thnh ti tiu ho. Sau khi tiu ho, cc sn phm cn thit cho

t bo c gi li, cc sn phm khng cn thit s c o thi ra khi t bo bng qu

trnh xut bo.

Tnh thc bo ca bch cu khng phi l v hn. Mt bch cu ht trung tnh c th thc bo

5-25 vi khun th cht. i thc bo c kh nng thc bo mnh hn nhiu. N c th thc bo

ti 100 vi khun. Khi nghin cu chc nng thc bo ca bch cu, ngi ta thng s dng

"ch s thc bo" nh gi chc nng ny.

Bch cu c mt khp ni trong c th cho nn vi khun t nhp bng bt kz ng no

cng b tiu dit. c bit bch cu trn gi nhng ni quan trng ca c th m vi khun d

xm nhp vo nh: da, nim mc, cc hc t nhin, phi, ng tiu ho, gan, lch. Tuy vy c

mt s vi khun b bch cu "nut" nhng khng "git" c nh mycobacteria, salmonella,

listera ... Nhng vi khun ny n nu ri nhn ln trong i thc bo. Bch cu N v i thc

bo cn cha nhng cht git vi khun. Mt s vi khun khng b tiu ho bi cc enzym ca

lysosom v chng c v bc bo v, hoc c cc yu t ngn chn tc dng ca cc enzym tiu

ho nhng li b cht bi cc cht git vi khun. Cc cht git vi khun l cc cht oxy ho mnh

nh superoxid (02-), hydrogenperoxid (H202), ion hydroxyl (0H-). Ngoi ra enzym

mieloperoxydase ca lysosom cng c kh nng git vi khun v n lm tan mng lipid ca vi

khun.

5. QU TRNH VIM.

Khi vim, c tnh ca m b thay i nh sau:

- Gin mch ti ch lm cho lu lng mu tng ln.

- Tng tnh thm mao mch gy ph n.

- ng dch k v dch bch huyt do fibrinogen v cc yu t gy ng mu thot vo.

- Tp trung nhiu bch cu N v i thc bo.

- Cc t bo ca m trng phng ln.

M b thng tn do bt kz mt nguyn nhn no (vi khun, chn thng, ho cht, nhit

v.v...) s gii phng histamin, bradykinin, serotonin, prostaglandin, cc yu t gy ng mu.

Lympho bo T hot ho gii phng ra lymphokin. Mt s cht trn hot ho i thc bo v

cng vi mt s sn phm khc do t bo tn thng v vi khun to ra gy ho ng

dng tnh vi bch cu N v i thc bo. Bch cu bm mch, xuyn mch v di chuyn ti

vim.

S ng dch k v bch huyt to ra mt bc tng bo v ngn cch gia vng vim v vng

lnh. S tp trung ca bch cu (i thc bo ti trc: sau vi pht, bch cu N ti sau: sau vi

gi) l mt hng ro th hai. ng thi vi s tp trung ca bch cu, t bo vim sn xut ra

cc globulin, cc sn phm phn hu bch cu vo mu, theo mu ti tc ng ln tu xng

lm tng sn xut bch cu (sau mt, hai ngy). Do qu trnh tng sn xut bch cu cho nn

trong mu s c nhiu bch cu non hn bnh thng (bch cu a).

vim hnh thnh mt ci hc cha xc vi khun, bch cu N, i thc bo, t chc hoi t gi

l m. M nhiu s b v thot ra ngoi hoc vo cc xoang, cc tng rng ca c th. Nu hng

ro bo v km, vi khun s lan rng vo cc c quan, c khi vo c mu. mu cng c i

thc bo v bch cu N sn sng tiu dit chng. Trong nhiu trng hp c th khng t bo

v c mnh cc triu chng nhim khun tng ln dn v cn phi c iu tr kp thi.

6. BCH CU A NHN A ACID .

Bch cu E c kh nng thc bo v ho ng ng rt yu nn khng quan trng trong nhim

trng thng thng. nhng ngi nhim k sinh trng (KST), s lng bch cu E tng cao v

chng ti cc nhim k sinh trng. Bch cu E gii phng ra cc cht git KST: men thu

phn t cc ht ca bo tng, oxy nguyn t, cc peptid v.v... Bch cu E cng tp trung nhiu

cc c phn ng d ng (tiu ph qun, da v.v...). Trong qu trnh tham gia vo phn ng d

ng, dng bo v bch cu B gii phng ra cc cht gy ha ng ng dng tnh vi bch

cu E. Bch cu E c tc dng kh c l cc cht gy vim do dng bo v bch cu B gii

phng ra. Bch cu E cng c th c tc dng thc bo chng qu trnh lan rng ca vim.

7- BCH CU A NHN A BASE.

Bch cu a nhn a base c th gii phng heparin, histamin, mt t bradykinin v serotonin.

Ti vim cc cht trn cng c dng bo gii phng ra trong qu trnh vim. Dng bo

v bch cu B ng vai tr quan trng trong phn ng d ng v khng th IgE gy phn ng d

ng c kh nng gn vo mng dng bo v bch cu B. Khi gp khng nguyn c hiu phn

ng vi khng th lm cho cc t bo ny b v ra v gii phng heparin, histamin, bradykinin,

serotonin, enzym thu phn lysosom v nhiu cht khc. Cc cht trn gy ra d ng.

8. BCH CU LYMPHO.

Bch cu lympho c chia thnh hai loi: lympho bo B v lympho bo T. Chng u c chung

ngun gc trong bo thai l cc t bo gc vn nng. Cc t bo ny s bit ho hoc c "x

l{" thnh cc lympho bo trng thnh. Mt s t bo lympho di tr tuyn c v c "x

l" y nn gi l lympho bo T (Thymus). Mt s t bo lympho khc c "x l" gan

(na u thi kz bo thai) v tu xng (na sau thi kz bo thai). Dng t bo lympho ny

c pht hin ln u tin loi chim v chng c "x l" bursa fabricicus (cu trc ny

khng c ng vt c v) nn c gi l lympho bo B (ly t ch bursa).

Sau khi c "x l{" cc lympho bo lu thng trong mu ri d tr m bch huyt, ri li

vo mu v.v... chu kz ti