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8/3/2019 SINH L HC V MU

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SINH L HC V MU

i. i cng

Mu c tim bm vo h thng mch mu v i khp c th. Trong cng tc chm sc sc kho, mu c bic quan tm v c nhiu xt nghim chn on c thc hin trn mu.

Mu c cu to bi huyt tng v thnh phn hu hnh. Huyt tng l thnh phn dch chim 55-60%Huyt tng gm nc v cc cht ho tan, trong ch yu l cc loi protein, ngoi ra cn c cc cht in gii, chtdinh dng, enzym, hormon, kh v cc cht thi. Thnh phn hu hnh chim 40-45%, gm hng cu, bch cu v tiucu.

S hin din ca cc thnh phn hu hnh v protein lm mu c qunh gp nm ln so vi nc. Mu c pH khong 7,35-7,4, ty thuc vo lng CO2 trong mu. V khi lng, mu chim khong 8% so vi ton c th.

Mu lu thng trong h mch v c ba chc nng chnh nh sau:

1. Vn chuyn

- Mu vn chuyn kh O2 v kh CO2.

- Vn chuyn cht dinh dng, cc sn phm o thi.

- Vn chuyn hormon t tuyn ni tit n cc t bo ch.

- Ngoi ra mu cn vn chuyn nhit.

2. Bo v- Mu c th chng li cc vi sinh vt gy bnh v cc c t.

- C th chng mt mu khi tn thng thnh mch nh qu trnh cm mu.

3. iu ho

- Mu tham gia iu ho pH ni mi thng qua h thng m ca n.

- iu ho lng nc trong t bo thng qua p sut thm thu keo ca mu.

- Mu cn tham gia iu nhit.

II. Qu trnh to mu

1. C quan to mu

Trong sut thi k phi thai, ln lt ti non hong, gan, lch, tuyn c, hch bch huyt v tu xng tham giahnh thnh cc t bo mu. Tuy nhin, sau khi sinh qu trnh to mu ch xy ra tu xng.

Di 5 tui, tu ca tt c cc loi xng u l tu , ngha l u c kh nng to mu. Sau la tui ny, cctu xng di (tr hai u xng cnh tay v xng i) b m xm ln dn v t tui hai mi tr i chng hon tontr thnh tu vng khng tham gia to mu na. Nh vy sau 20 tui, ch c tu xng dt v hai u xng i, hai uxng cnh tay tham gia to mu.

Tu xng cha cc t bo gc to mu a nng (pluripotential hemopoietic stemcell). Cc t bo ny sinh snlin tc trong sut cuc i. Mt phn nh s c gi li nh l cc t bo ngun, tuy rng s lng s gim dn theotui. Phn ln c bit ho thnh cc t bo mu khc nhau.

2. Qu trnh bit ho

Cc t bo gc to mu a nng c bit ho thnh cc loi t bo gc bit ho (committed stem cell). Qutrnh sinh sn v bit ho tip tc to thnh mi loi t bo mu s din ra qua nhiu giai on (xem hnh 1). Cc qutrnh ny cn s tham gia ca cc cht kch thch khc nhau nh:

- Erythropoietin (EPO): kch thch to hng cu

- Thrombopoietin (TPO): kch thch to tiu cu

- Cc yu t kch thch to cm (CSFs: colony-stimulating factors) v cc interleukin (IL): kch thch to bch curing IL-3 c tc dng tng sinh sn tt c cc loi t bo gc.

- Yu t t bo gc (SCF: stem cell factor): kch thch s sinh sn ca cc t bo gc bit ho, n c hiu qu lnnhiu dng t bo.


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III. Hng cu

1. Hnh dng - cu trc

Hng cu chim hn 99% trong cc thnh phn hu hnh ca mu. l nhng t bo c hnh a hai mt lmng knh 7-8 mm, b dy phn ngoi vi 2-2,5 mm v phn trung tm 1 mm, th tch trung bnh 90-95 mm3. Hnh dngny c hai li im nh sau:

- Tng din tch b mt tip xc lm tng kh nng khuch tn kh thm 30% so vi hng cu cng th tch m cdng hnh cu.

- Lm cho hng cu tr nn cc k mm do, c th i qua cc mao mch hp m khng gy tn thng maomch cng nh bn thn hng cu.

Hng cu khng c nhn cng nh cc bo quan. Thnh phn chnh ca hng cu l hemoglobin (Hb), chim34% trng lng (nng 34 g/dl trong dch bo tng). Cu trc ca hng cu c bit thch ng vi chc nng vnchuyn kh oxy.

2. S lng

ngi bnh thng, s lng hng cu trong mu ngoi vi l:

Nam: 5.400.000 300.000 /mm3

N: 4.700.000 300.000/mm3

Theo kt qu bc u nghin cu mt s ch tiu sinh hc ca ngi Vit Nam nm 1996, s lng hng cutrong mu ca ngi Vit Nam bnh thng c khc nhau tu theo tc gi. (bng 1).

Bng 1: S lng hng cu trong mu ngoi vi ca ngi Vit Nam

Tc gi Trung Phn

(min Bc)

Nguyn Ngc Minh

(min Trung)

Trn Vn B

(min Nam)

Nam (/mm3) 5.110.000 300.000 4.510.000 410.000 4.920.000 680.000

N (/mm3

) 4.600.000 250.000 4.320.000 210.000 4.520.000 540.000S lng hng cu c th thay i trong mt s trng hp sinh l. tr s sinh, s lng hng cu cao trong vng mthai tun u, sau c hin tng v hng cu gy vng da sinh l. Ngoi ra, s lng hng cu c th tng nhngngi lao ng nng, sng vng cao.


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Hnh 1: Qu trnh bit ho cc dng t bo mu

3. Chc nng

Chc nng ch yu ca hng cu l vn chuyn oxy ti cc t chc. Ngoi ra hng cu cn c cc chc nng sau: vnchuyn mt phn CO2 (nh hemoglobin), gip huyt tng vn chuyn CO2(nh enzym carbonic anhydrase), iu hocn bng toan kim nh tc dng m ca hemoglobin.

3.1. Cu trc ca hemoglobin
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Hemoglobin cn gi huyt sc t, l chromoprotein gm hai thnh phn l nhn heme v globin. (hnh 2)

Heme l mt sc t . Mi heme gm mt vng porphyrin v mt Fe2+ chnh gia. Mt phn t hemoglobin c bn nhnheme, chim 5%.

Globin l mt protein gm bn chui polypeptid ging nhau tng i mt. Hemoglobin ngi bnh thng l HbA gm haichui a v hai chui b. Hemoglobin thi k bo thai l HbF gm hai chuia v hai chui g.

Hnh 2: Cu to phn t hemoglobin

S bt thng ca cc chui globin s lm thay i c im sinh l ca phn t Hb. V d, trong bnh thiu muhng cu hnh lim, acid amin valin thay th cho glutamic ti mt v tr trong mi chui b lm HbA tr thnh HbS.

Nng hemoglobin ca ngi bnh thng l:

Nam: 13,5-18 g/100 ml (g%)

N: 12-16 g/100 ml (g%)

Tr em: 14-20 g/100 ml (g%)

Nng hemoglobin ca ngi Vit Nam bnh thng c nghin cu nm 1996 c tr s khc nhau tu thetng tc gi. (bng 2)

Bng 2: Nng hemoglobin ca ngi Vit Nam bnh thng.

Tc gi Trung Phn

(min Bc)

Nguyn Ngc Minh

(min Trung)

Trn Vn B

(min Nam)

Nam 157 7 g/l 133,9 9,8 g/l 142,8 10,8 g/l

N 135 7 g/l 130 5,7 g/l 128,5 10,8 g/l

3.2. Chc nng vn chuyn kh

3.2.1. Vn chuyn kh O2

Hng cu vn chuyn O2 t phi n t chc nh phn ng sau:

Hb + O2 HbO2 (oxyhemoglobin)

Trong O2 c gn lng lo vi Fe2+. y l phn ng thun nghch, chiu phn ng do phn p O2 quynh. Trong phn t Hb, O2 khng b ion ho m n c vn chuyn di dng phn t O2.
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- Khi ht phi khng kh nhiu CO (carbon monoxide), hemoglobin s kt hp CO to racarboxyhemoglobin theo phn ng:

Hb + CO HbCO

i lc ca Hb i vi CO gp hn 200 ln i vi O2, v vy mt khi kt hp vi CO th Hb khng cn kh nng vnchuyn O2 na. Du hiu u tin l da sng, bnh nhn ri vo trng thi kch thch, ri bun ng, hn m v tvong. Kh CO thng c sinh ra khi t chy nhin liu khng hon ton. iu tr bng cch a bnh nhn ra khi mtrng nhiu CO, ng thi cho th O2. Lng CO trong khng kh l ch s o mc nhim mi trng.

- Khi mu tip xc vi nhng thuc hoc ho cht c tnh oxy ho, Fe2+ trong nhn heme chuyn thnhFe3+v hemoglobin tr thnh methemoglobin khng cn kh nng vn chuyn O2. Methemoglobin khi hin dintrong mu nhiu s gy triu chng xanh tm. Tnh trng ny xy ra khi ng c mt s dn cht ca anilin,sulfonamide, phenacetin, nitroglycerin, nitrate trong thc phm ...

3.2.2. Vn chuyn kh CO2

Hng cu vn chuyn CO2 t t chc v phi theo phn ng sau:

Hb + CO2 HbCO2 (carbaminohemoglobin)

CO2 c gn vi nhm NH2 ca globin. y cng l phn ng thun nghch, chiu phn ng do phn pCO2 quyt nh. Ch khong 20% CO2 c vn chuyn di hnh thc ny, cn li l do mui kim ca huyt tng vnchuyn.

4. S sinh sn hng cu

4.1. Qu trnh bit ho dng hng cu

S 1: Qu trnh bit ho dng hng cu

Tin nguyn hng cu l t bo u tin ca dng hng cu m chng ta nhn dng c. Qu trnh bit ho ttin nguyn hng cu din ra theo s 1.

Cc giai on t t bo gc n hng cu li din ra trong tu xng, sau hng cu li c phng thch ramu ngoi vi 24-48 gi th mng li bin mt v tr thnh hng cu trng thnh. T l hng cu li trong mu ngovi khng qu 1%. T l ny cho php nh gi tc sinh hng cu ca tu xng sau liu trnh iu tr thiu mu hocsau khi b mt mu cp.

S tng hp hemoglobin xy ra t giai on tin nguyn hng cu v ngy cng tng dn. n giai on nguynhng cu a acid th t mc bo ho.
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4.2. S iu ho sinh sn hng cu

S lng hng cu trong h thng tun hon c iu ho cht ch n ch thay i trong mt phm vi hpS lng hng cu phi m bo hai yu cu sau:

- cung cp oxy cho t chc.

- Khng qu nhiu trnh cn tr s lu thng mu.

Nng oxy t chc l yu t chnh kim sot tc sinh hng cu. Tc sinh hng cu s tng trong nhngtrng hp lng oxy vn chuyn n t chc khng p ng nhu cu ca t chc v ngc li. Tc sinh hng

cu s tng trong cc trng hp sau:

- Khi thiu mu do mt mu, tu xng s tng sinh sn hng cu. Ngoi ra, nhng ngi b thng tntu xng mt phn do liu php tia X chng hn, phn tu xng cn li s tng sinh sn hng cu p ngnhu cu c th.

- Nhng ngi sng vng cao.

- Cc trng hp suy tim ko di hoc nhng bnh phi mn tnh.

Yu t kch thch sinh sn hng cu l ni tit t erythropoietin. ngi bnh thng, 90% erythropoietin do thn tit ra,phn cn li ch yu do gan sn xut. Khi thiu oxy t chc, erythropoietin s c tng tit trong mu v chnh n thc y qu trnh to tin nguyn hng cu t t bo gc to mu trong tu xng. Khi tin nguyn hng cu chnh thnh th erythropoietin li thc y n nhanh chng chuyn qua cc giai on nguyn hng cu hnh thnh hngcu trng thnh. Ngoi ra erythropoietin cn tng tng hp Hb trong nguyn hng cu v tng vn chuyn hng cu lra mu ngoi vi.

4.3. Cc thnh phn dinh dng tham gia to hng cu

to hng cu, cn phi cung cp y protein, st, v cc vitamin B12, B9 (acid folic).

- Protein cn cho s tng hp cc chui globin v cc thnh phn cu trc ca hng cu.

- St cn to nhn heme: nhu cu st hng ngy l 1 mg nam gii v 2 mg n. i vi ph n cthai nhu cu st cng tng cao nn phi cung cp thm vin st mi ngy.

- Vitamin B12 v acid folic cn cho qu trnh tng hp DNA phc v s phn chia t bo. Nhu cu B 12 mngy l 1-3 mg.

5. i sng hng cu

i sng trung bnh ca hng cu trong mu ngoi vi l 120 ngy. Theo thi gian, mng hng cu s mt dn tnh mmdo v cui cng hng cu s v khi i qua cc mao mch nh ca lch. Hemoglobin phng thch ra t hng cu v s bthc bo bi cc i thc bo c nh ca gan, lch v tu xng.

i thc bo s gii phng st vo mu; st ny cng vi st t thc n do rut non hp thu, c vn chuyndi dng transferrin dn tu xng to hng cu mi, hoc n gan v cc m khc d tr di dng ferritin vhemosiderin.

Phn porphyrin ca heme s c chuyn ho qua nhiu giai on trong i thc bo to thnh sc tbilirubin, cht ny c gii phng vo mu, n gan ri bi tit vo mt. S chuyn ho ca bilirubin s c nghin cuk trong chng tiu ho.

Ngoi ra phn globin ca hemoglobin c ging ho thnh cc acid amin m s c s dng tng hp ccprotein cho c th.

6. Mt s ri lon lm sng ca dng hng cu

6.1. Thiu mu

Theo T chc Y t th gii, thiu mu l gim nng hemoglobin:

Nam: < 13 g/100 ml mu


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N: < 12 g/100 ml mu

Tr s sinh: < 14 g/100 ml mu

Thiu mu c th do giun mc, xut huyt, huyt tn, suy tu ...

6.2. Bnh a hng cu

Cn gi l bnh Vaquez, gy ra do s khim khuyt gen xy ra trong dng nguyn bo to mu. Nhng nguyn

bo ny khng ngng to hng cu d s lng qu . S lng hng cu thng l 7-8 triu/mm

3

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IV. Bch cu

Bch cu l nhng t bo mu c tc dng bo v c th chng li cc tc nhn gy bnh.

1. Cc loi bch cu

Da vo hnh dng, cu trc v cch bt mu phm nhum, ngi ta chia bch cu ra lm hai nhm chnh lbch cu ht v bch cu khng ht.

1.1. Bch cu ht

Cha nhng ht trong bo tng m c th thy di knh hin vi quang hc. Tu theo cch bt mu phmnhum ca cc ht m chng c tn l bch cu ht trung tnh, a acid, a kim. Ngoi ra, do nhn ca cc bch cu hny c nhiu thu nn chng cn c tn l bch cu a nhn.

1.2. Bch cu khng ht

Trong bo tng khng c cc ht m c th thy c di knh hin vi quang hc do kch thc chng nh vbt mu phm nhum km. C hai loi bch cu khng ht l bch cu lympho v bch cu mono. Nhn ca cc bchcu khng ht ny khng chia thu nn chng cn c tn l bch cu n nhn.

2. S sinh sn v i sng bch cu

2.1. Bch cu ht v bch cu mono

Ton b qu trnh sinh sn v bit ho to nn cc loi bch cu ht v bch cu mono din ra trong tu xng.Chng c d tr sn tu xng, khi no c th cn n, chng s c a vo mu lu thng.

Bch cu ht sau khi ri tu xng th lu hnh trong mu khong 4-8 gi ri xuyn mch vo t chc, tn tthm khong 4-5 ngy. Khi bch cu thc hin chc nng bo v c th ca minh, chng hn chng nhim trng, th ns cht sm hn.

Bch cu mono cng c thi gian lu hnh trong mu ngn, khong 10-20 gi. Sau s xuyn mch vo tchc. Ti t chc chng s tng kch thc v tr thnh i thc bo t chc. dng ny chng c th sng hng thngthm ch hng nm.

2.2. Bch cu lympho

Cc t bo lympho u c chung ngun gc t trong bo thai l t bo gc to mu a nng. Cc t bo ny sbit ho thnh t bo gc bit ho ca dng lympho to ra t bo lympho. Trc khi tr thnh cc t bo lymphotrng thnh khu tr cc t chc bch huyt, chng c x l ti nhng ni khc nhau trong c th. Mt s di trn tuyn c c x l v c gi l lympho T. Mt s khc c x l gan trong nhng thng gia cathai k, tu xng trong nhng thng sau ca thai k v sau khi sinh, chng c gi l lympho B.

T cc t chc bch huyt, bch cu lympho vo h tun hon lin tc theo dng bch huyt. Sau vi gi, chngxuyn mch vo t chc ri vo dng bch huyt tr v t chc bch huyt hoc vo mu ln na ri ln na ... Cc


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bch cu lympho c thi gian sng hng tun, hng thng hoc thm ch hng nm tu thuc nhu cu ca c th.

3. Chc nng ca bch cu

Chc nng chung ca bch cu l chng li cc tc nhn l xm nhp vo c th. Nhn chung, chng c cc ctnh sau thch hp vi chc nng ny:

- Xuyn mch: t bin i hnh dng chui qua gia cc t bo ni m mch mu vo t chc xung quanh.

- Vn ng: theo kiu a-mp (bng chn gi) n cc t chc cn n.

- Ho ng ng: bch cu b hp dn n v tr tn thng khi c cc ho cht c gii phng ra bi t bo tthng hoc vi khun, v khi c cc phc hp min dch.

- Thc bo: bt cc vt l a vo trong bo tng ri tiu ho chng.

Tuy nhin khng phi loi bch cu no cng c y cc c tnh trn.

Hnh 3: Cc t bo thc bo di chuyn t mu n t chc tn thng

3.1. Chc nng ca bch cu ht trung tnh

Bch cu ht trung tnh l hng ro ca c th c kh nng chng li vi khun sinh m. Chng rt vn ng vthc bo tch cc.

Bch cu trung tnh c th tiu ho, hu hoi nhiu loi vi khun, nhng thnh phn nh, v fibrin. Hu ht cc h

bo tng ca chng l cc tiu th cha enzym thu phn. Cc ht khc cha cc protein khng khun. Ngoi ra, bchcu ht trung tnh cn cha cc cht oxy ho mnh c tc dng tiu dit vi khun.

Bch cu ht trung tnh l bch cu u tin n v tr vi khun xm nhp vi s lng ln. Trong qu trnh thcbo vi khun, nhiu bch cu trung tnh b cht v to thnh m ti v tr tn thng. Mi bch cu ny thc bo ti akhong 5-20 vi khun.

3.2. Chc nng ca bch cu ht a kim

Bch cu ht a kim rt ging mt loi t bo khc trong t chc bn ngoi mao mch gi l dng bo (mascell).
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Bch cu ht a kim v dng bo c th phng thch heparin ngn cn qu trnh ng mu v thc y s vnchuyn m t mu sau ba n nhiu cht bo.

Cc t bo ny ng vai tr quan trng trong phn ng d ng. Do cc khng th gy phn ng d ng (loi IgEc khuynh hng n gn trn b mt dng bo v bch cu a kim. Khi c s kt hp gia khng th ny vi d ngnguyn, dng bo v bch cu a kim s v ra v gii phng histamine, cng nh bradykinin, serotonin, cht phnng chm ca sc phn v (slow-reacting substance of anaphylaxis), enzym tiu protein....to nn bnh cnh in hnhca d ng.

3.3. Chc nng bch cu ht a acid

Bch cu ht a acid t vn ng hn bch cu trung tnh v thc bo cng t tch cc hn, chng khng thc bo vikhun.

Chc nng u tin ca bch cu ht a acid l kh c protein l nh cc enzym c bit trong ht bo tngBch cu a acid thng tp trung nhiu nim mc ng h hp, tiu ho, tit niu-sinh dc ngn chn cc tnhn l xm nhp c th.

Chng c th tit ra cc cht c i vi k sinh trng. c bit l cc loi sn mng (schistosomum) hoc giunxon (trichinella).

Bch cu ht a acid cn tp trung ni c phn ng d ng xy ra, chng tit ra cc enzym chng li tc

dng ca histamine v cc cht trung gian khc trong phn ng d ng. Ngoi ra, chng cn c kh nng thc bo ccphc hp khng nguyn-khng th. V vy, chng ngn cn khng cho tin trnh vim lan rng.

3.4. Chc nng bch cu mono - i thc bo

Cc bch cu mono cha thc s trng thnh, kh nng tiu dit tc nhn nhim khun ca chng cn kmNhng khi vo trong t chc, tr thnh i thc bo vi kch thc ln hn v nhiu tiu th trong bo tng, chng ckh nng chng tc nhn gy bnh rt mnh lit. Kh nng thc bo ca chng mnh hn bch cu ht trung tnh nhiu,chng c th thc bo khong 100 vi khun. i thc bo cn c th thc bo cc thnh phn ln hn nh hng cucht, k sinh trng st rt. Ngoi ra, chng cn c lipase gip tiu ho cc vi khun c v bc lipid dy. Sau khi thc bochng c th y cc sn phm ra v thng sng st vi thng.

Cc i thc bo cn c chc nng trnh din khng nguyn cho cc t bo c thm quyn min dch.

3.5. Chc nng bch cu lympho

C 3 loi t bo lympho l:

3.5.1. T bo dit t nhin (NK: natural killer)

Cc t bo NK hin din lch, hch, tu xng v mu. Chng thng tn cng cc vi sinh vt gy bnh v mt st bo khi u tin pht. C ch tc dng ca chng cha c r rng.

3.5.2. Lympho B

Bch cu lympho B bo v c th bng p ng min dch dch th (qua trung gian khng th). N chng li ccloi vi khun v mt s virus.

Khi c cc vi khun xut hin, lympho B nhn din khng nguyn tng ng v c hot ho. Khi n c khnng phn bo v bit ho thnh tng bo (plasma cell). Cc tng bo ny s sn xut khng th chng li vi khun xm nhp. Khng th tiu dit cc vi khun hoc bt hot c t ca chng.

Mt s lympho B c sinh ra trn khng tr thnh tng bo m tr thnh lympho B nh sn sng p ngnhanh v mnh khi c cng loi vi khun xm nhp ln sau.

3.5.3. Lympho T


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Bch cu lympho T l t bo tham gia p ng min dch qua trung gian t bo. Lympho T c kh nng chng li cc tcnhn nh virus, nm, t bo mnh ghp, t bo ung th v vi loi vi khun. Khi c cc tc nhn xut hin trong cth, cc lympho T s nhn din khng nguyn c hiu vi n v c hot ho. Sau chng tr nn ln hn, sinh snto nn hng ngn lympho T c th nhn din khng nguyn xm nhp ny. C 3 loi lympho T chnh:

- T gip (Th: helper): kch thch s pht trin v sinh sn ca cc lympho Tc, T c ch. Th cn kchthch s pht trin v bit ho lympho B thnh tng bo. Ngoi ra, Th cn tit cc cht lm tng cng hotng bch cu trung tnh v i thc bo.

- T c (Tc: cytotoxic): tiu dit trc tip cc t bo b nhim tng ng. Tccng tit cc cht khuch kh nng thc bo ca i thc bo.

- T c ch (Ts: suppressor): pht trin chm hn, n c tc dng c ch lympho Tc v Th lm cho p ngmin dch khng pht trin qu mc.

Mt s lympho T tr thnh t bo T nh c kh nng khi pht mt p ng min dch tng t khi c cng loi tc nhngy bnh (khng nguyn) xm nhp nhng mc nhanh, mnh hn nhiu, gi l p ng min dch ln hai.

Lu :

- Cc Th thuc loi lympho T4, cn Tc v Ts thuc loi lympho T8.

- T bo Th ng vai tr quan trng trong c qu trnh min dch trung gian t bo ln min dch dch thTrong bnh AIDS cc HIV tn cng dng T4 (ch yu l Th) nn cc p ng min dch b t lit v c ch bo vkhng c hiu cng b suy gim. Bnh nhn s cht do nhim trng c hi.

- p ng min dch ln sau nh vai tr ca T nh hoc B nh l c s min dch ca vic chng nga phng bnh.

4. S lng bch cu - Cng thc bch cu

4.1. S lng bch cu

Bnh thng s lng bch cu trong mu trung bnh khong 7000/mm3.

Tng trong cc bnh nhim khun cp, vim hoc Leukemia

Gim trong cc trng hp suy tu.

4.2. Cng thc bch cu

Cng thc bch cu l t l phn trm ca cc loi bch cu. C nhiu loi cng thc bch cu nhng trn lmsng thng s dng cng thc bch cu thng thng. Ngi bnh thng c th c cng thc bch cu nh sau:

- Bch cu a nhn trung tnh: 60-70 %

- Bch cu a nhn a acid: 2-4 %

- Bch cu a nhn a kim: 0,5-1 %

- Bch cu mono: 3-8 %

- Bch cu lympho: 20-25 %

S thay i t l cc loi bch cu gip cc nh lm sng chn on nguyn nhn.

4.2.1. Bch cu trung tnh

- Tng khi nhim khun cp, bng, stress, vim.

- Gim khi nhim tia x, s dng mt vi loi thuc (nh thuc khng gip), bnh Lupus ban .

4.2.2. Bch cu a acid

- Tng khi c phn ng d ng, nhim k sinh trng, bnh t min, suy thng thn.

- Gim khi s dng mt s thuc (corticoid), hi chng Cushing, stress.

4.2.3. Bch cu a kim

- Tng trong mt s trng hp d ng, bnh bch cu, suy gip.


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- Gim trong trng hp mang thai, rng trng, stress, cng gip (v bch cu ny chim t l thp nn rkh pht hin gim).

4.2.4. Bch cu lympho

- Tng trong nhim virus, bnh min dch, bnh bch cu.

- Gim khi b bnh nng ko di, tng nng steroid, b c ch min dch.

4.2.5. Bch cu mono

- Tng khi b nhim virus, nm, lao, mt s bnh bch cu v bnh mn tnh.

- Gim bch cu m-n rt him xy ra.5. Mt s ri lon lm sng dng bch cu

5.1. Gim bch cu

Gim bch cu thng xy ra khi tu xng ngng sn xut bch cu, lm vi khun v tc nhn gy bnh khcc iu kin thun li xm nhp vo c th.

Bnh nhn c th cht trong vng 1 tun do nhim khun nng.

Nguyn nhn thng do b nhim tia gam-ma (phng x nguyn t), ho cht c nhn benzene, anthraceneNgoi ra c th do mt s thuc nh chloramphenicol, thiouracil, barbiturate.

5.2. Bnh bch cu (Leukemia, ung th mu)

l s sinh sn bch cu khng th kim sot gy nn do t bin ung th ca cc t bo dng tu hoc dnglympho. Bnh bch cu c c trng bi s gia tng qu mc s lng bch cu bt thng trong mu.

Bnh nhn thng b nhim trng, thiu mu nng, d xut huyt

Bnh nhn bnh bch cu cp c th cht sau t thng khng iu tr, cn bnh bch cu mn c th sng 10-20nm.

V. Nhm mu

Trn mng hng cu ngi, ngi ta tm ra khong 30 khng nguyn thng gp v hng trm khng nguynhim gp khc. Hu ht nhng khng nguyn l yu, ch c dng nghin cu di truyn gen v quan h huyt thngTuy nhin c hai nhm khng nguyn c bit quan trng c th gy phn ng trong truyn mu l h thng khngnguyn ABO v Rh.

1. H thng nhm mu ABO

1.1. Phn loi

Trong h thng ny c 2 loi khng nguyn l A v B nm trn mng hng cu. Ngoi ra trong huyt tng cnc 2 loi khng th l khng th khng A (khng th a) v khng th khng B (khng th b). Khng th a c kh nngngng kt khng nguyn A, khng th b c kh nng ngng kt khng nguyn B.

Ngi ta da vo s hin din khng nguyn A, B trn mng hng cu phn loi h thng nhm mu ABO(bng 3).

Bng 3: H thng nhm mu ABO

Tn nhm mu T l % KN trn mng hng cu

KT trong huyt tng

Da trng Vit Nam

A 41 21,5 A b


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B 9 29,5 B a

AB 3 6 A v B Khng c a v b

O 47 43 Khng c A, B a v b

S xut hin khng nguyn A, hoc khng nguyn B trn mng hng cu c quy nh bi gien (gene).

Khng th a v b c to ra bi cc t bo sn xut khng th. Sau khi sinh, khng th cha xut hin tronghuyt tng. Hai n tm thng sau c th a tr mi bt u sn xut khng th (ngi nhm mu A th sn xukhng th b, tng t cho cc nhm mu khc). Nng khng th t ti a vo nhng nm 8-10 tui, sau n s

gim dn.

1.2. Phn ng truyn mu

Khi truyn nhm nhm mu, phn ng truyn mu c th xy ra, trong hng cu ca mu ngi cho b ngngkt, rt him khi mu truyn vo gy ngng kt hng cu ngi nhn.

Cc hng cu ngng kt thnh tng m m c th bt kn cc mch mu nh. Vi gi hoc vi ngy tip theo, sxy ra tan mu (v hng cu). i khi ngay sau khi truyn nhm nhm mu, hin tng tan mu xy ra lp tc. Mt trongnhng hu qu gy t vong ca phn ng truyn mu l suy thn cp.

1.3. ng dng trong truyn mu

1.3.1. Nguyn tc truyn mu

- Nguyn tc chung: Khng c khng nguyn v khng th tng ng gp nhau. Nh vy chng ta chc php truyn mu cng nhm.

- Nguyn tc ti thiu: Khi truyn mt lng mu nh (


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Hnh 4: S truyn mu kinh in

2. H thng nhm mu Rhesus (Rh)

2.1. Phn loi

C 6 loi khng nguyn Rh, chng c k hiu l C, D, E, c, d, e. Mt ngi c khng nguyn C th khng c c

v ngc li, iu ny cng ng i vi cc cp D-d v E-e. Do phng thc di truyn ca cc yu t ny, mi ngchng ta c 3 khng nguyn thuc 3 cp C-c, D-d, E-e (chng hn CDE; CdE; cdE; cDe...).

Khng nguyn D l thng gp nht v c tnh khng nguyn mnh nht nn nhng ngi mang khng nguyn D cgi Rh dng, nhng ngi khng mang khng nguyn D c gi l Rh m.

Mt iu cn lu l trong h thng nhm mu Rh, khng th khng Rh khng c sn t nhin trong mu. Khng th chsinh ra trong mu ngi Rh m khi ngi ny c truyn mu Rh dng hoc trng hp m Rh m mang bo thai Rhdng. l kt qu ca qu trnh p ng min dch.

Bng 4: H thng nhm mu Rhesus

Tn nhm mu Khng nguyn D Khng th tnhin

T l %

u M Kinh (VN) Mng

Rh + C Khng 85 99,92 100

Rh - Khng Khng 15 0,08 0

2.2. Tai bin do bt ng nhm mu h Rh

2.2.1. Trong truyn mu

Ngi nhm mu Rh m c truyn mu Rh dng, ln u tin hu nh khng xy ra tai bin. Tuy nhin, cth ngi ny bt u sn xut khng th khng Rh. Nng khng th t ti a sau 2-4 thng. Nu sau ngi nyli c truyn mu Rh dng th tai bin c th xy ra do khng th khng Rh c sn cng vi khng th khng Rh

c to ra do p ng min dch ln hai s gy ngng kt hng cu Rh dng c truyn vo.

Cn lu rng, c mt s ngi Rh m trong ln nhn mu Rh dng u tin sn xut khng th khng Rhvi s lng c ngha sau 2-4 tun. Nh vy, khng th c th gy ngng kt nhng hng cu Rh dng cn luthng trong mu. Tuy nhin, phn ng xy ra mun ny rt nh nhng.

2.2.2. Trong sn khoa

Xy ra i vi nhng ngi ph n Rh m ly chng Rh dng. Khi c thai, thai nhi c th l Rh dng hoc mTrong ln mang thai Rh dng u tin, mt lng mu Rh dng ca thai nhi s vo tun hon m ch yu l lc sinhv kch thch c th ngi m sn xut khng th khng Rh. a tr sinh ra trong ln ny khng b nh hng g c. Tuynhin, n ln mang thai tip theo, khng th khng Rh s vo tun hon thai nhi. Nu l thai Rh dng th khng th
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khng Rh c th lm ngng kt hng cu thai nhi v gy cc tai bin sy thai, thai lu, hoc a tr sinh ra b hi chngvng da tan mu nng.

Tht ra, trong thi gian mang thai yu t Rh ca bo thai phng thch vo trong dch bo thai v c th khuchtn vo mu m. Tuy nhin, trong ln mang thai u tin (ln u tin tip xc khng nguyn Rh) lng khng th to ra c th ngi m khng cao gy hi cho thai nhi.

Hnh 5: Tai bin sn khoa trong bt ng nhm mu Rhesus

VI. Cm mu

Cm mu l qu trnh ngn cn s chy mu. Khi mch mu b tn thng hoc t, qu trnh cm mu phi png nhanh chng, khu tr ti vng tn thng v c kim sot cht ch. Qu trnh cm mu c thc hin nhnhng c ch: co mch, hnh thnh nt tiu cu, ng mu, tan cc mu ng hoc pht trin m x trong cc mu ng ng kn vt thng.

1. Co mch

Ngay khi mch mu b tn thng, thnh mch co li do cc c ch sau:

- Phn x thn kinh do au.

- S co mch ti ch, c khi pht trc tip bi thng tn thnh mch.

- Cc yu t th dch t t chc thng tn v tiu cu (thromboxane A2, serotonin vepinephrine).Thnh mch b thng tn cng nhiu th co mch cng mnh. S co mch ti ch c th ko di nhiu pht n

vi gi. Trong thi gian ny c th din ra s hnh thnh nt tiu cu v ng mu.

ngha: S co mch tc thi ny hn ch lng mu ra khi thnh mch tn thng.

2. S hnh thnh nt tiu cu

2.1. Sinh l tiu cu

Tiu cu thc cht l mt mnh t bo c v ra t t bo nhn khng l. Sau khi c phng thch t tuxng, ch c 60-75% tiu cu lu thng trong mu, phn cn li c gi lch.
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S lng bnh thng ca tiu cu trong mu l 150.000-300.000/mm3.

i sng tiu cu thay i t vi ngy n hai tun.

Tiu cu c kch thc 2-4 mm, khng c nhn nhng bo tng c nhiu ht. C 2 loi ht l:

- Ht alpha cha PDGF (platelet-derived growth factor) c tc dng gip lin vt thng.

- Ht m c cha ADP, ATP, Ca2+, serotonin v epinephrine.

Ngoi ra tiu cu cn cha cc enzym tng hp thromboxane A2; yu t n nh fibrin, tiu th v cc kho d

tr Ca2+

. c bit, trong tiu cu c cc phn t actin, myosin, thrombosthenin gip n co rt.

Mng ca tiu cu cha mt lng ln phospholipid. B mt ca tiu cu c mt lp glycoprotein ngn cn ndnh vo ni mc bnh thng.

2.2. S hnh thnh nt tiu cu

Din ra theo cc pha nh sau:

- Kt dnh tiu cu: khi thnh mch b tn thng, lp collagen nm bn di t bo ni mc mch mc l ra. Tiu cu s n dnh vo lp collagen ny.

- Tiu cu gii phng cc yu t hot ng: sau khi tiu cu kt dnh vi collagen, n tr nn c hot ho

Tiu cu phnh to ra, th cc chn gi v gii phng nhiu cht, trong c mt lng ln ADP, thromboxane A2.- Kt tp tiu cu: ADP v thromboxane A2 hot ho cc tiu cu gn v lm chng dnh vo lp tiu cuban u gi l kt tp tiu cu. Ri lp tiu cu n sau ny li gii phng cc cht hot ng lm hot ho vdnh thm lp tiu cu khc. C nh vy, cc lp tiu cu n dnh vo ch tn thng cng lc cng nhiu tonn nt tiu cu.

Nu thng tn mch mu l nh th bn thn nt tiu cu c th lm ngng chy mu, nhng nu thng tnln hn th phi nh thm s hnh thnh cc mu ng.

ngha: S hnh thnh nt tiu cu c vai tr c bit quan trng trong vic btkn cc thng tn nh ccmch mu nh xy ra hng trm ln mi ngy.

3. Qu trnh ng mu

Bnh thng mu trong lng mch lun dng lng (sol). Tuy nhin, khi mch mu b tn thng hoc mu chy

ra khi c th, mu s chuyn sang dng c (gel). Qu trnh hnh thnh dng gel c gi l qu trnh ng mu.

Trong c th c hn 50 cht nh hng n s ng mu. Nhng cht thc y ng mu c gi l yu tng mu, nhng cht ngn cn ng mu c gi l cht chng ng.

Cc yu t ng mu kinh in c k hiu theo th t bng ch s La M nh sau:

- Yu t I : Fibrinogen

- Yu t II : Prothrombin

- Yu t III : Thromboplastin t chc

- Yu t IV : Calcium

- Yu t V : Proaccelerin

- Yu t VII : Proconvertin- Yu t VIII : Yu t chng chy mu A

- Yu t IX : Yu t chng chy mu B cn gi l yu t Christmas

- Yu t X : Yu t Stuart

- Yu t XI : Tin Thromboplastin huyt tng

- Yu t XII : Yu t Hageman

- Yu t XIII : Yu t n nh Fibrin

Qu trnh ng mu l mt chui cc phn ng xy ra theo kiu bc thang c chia thnh 3 giai on nh sau:


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3.1. Giai on thnh lp phc hp prothrombinase

Prothrombinase c hnh thnh bi 2 con ng: ngoi sinh v ni sinh.

3.1.1. Con ng ngoi sinh

Con ng ny c khi pht bi yu t III (l thromboplastin t chc gmphospholipid v lipoprotein) c tira t b mt cc t bo t chc tn thng ngoi thnh mch. Yu t III vo mu hot ho yu t VII. Ri yu t VIIa (VIhot ho) cng thromboplastin t chc hot ho tip yu t X. Yu t Xa kt hp vi phospholipid (t t chc) v yu t Vcng s c mt Ca2+ to nn phc hp prothrombinase.

S 2: S hnh thnh prothrombinase theo con ng ngoi sinh

3.1.2. Con ng ni sinh

Con ng ny c khi pht khi bn thn mu b tn thng hoc mu tip xc vi lp collagen (c l ra dot bo ni mc tn thng). iu ny dn n s hot ho yu t XII v tiu cu (gii phng phospholipid tiu cu). Yut XIIa s hot ho yu t XI, phn ng ny cn c kininogen v prekallikrein. Yu t XIa li hot ho yu t IX. Yu tVIIa trong con ng ngoi sinh cng tham gia hot ho yu t IX. Yu t IXa cng vi yu t VIIIa (yu t VIII c hoho bi thrombin), phospholipid tiu cu s hot ho yu t X. Yu t Xa kt hp vi phospholipid (t tiu cu) v yu tV cng s c mt Ca2+ to nn phc hp prothrombinase.

* Ngoi tr 2 bc u ca con ng ni sinh, tt c cc bc khc ca c hai con ng u cn Ca2+.

3.2. Giai on thnh lp thrombin

Sau khi prothrombinase c hnh thnh, n chuyn prothrombin thnh thrombin ch sau vi giy.

Trong phc hp prothrombonase, yu t Xa l mt enzym phn gii protein thc s, n chuyn prothrombinthnh thrombin. Mt khi thrombin c hnh thnh, n s hot ho yu t V. Ri yu t Va cng thc y tc dng cayu t Xa to nn s iu ho ngc dng tnh (positive feedback).

Thrombin cng l enzym phn gii protein, n cn c th tc ng ln chnh prothrombin tng to thrombinNgoi ra n cn thc y hot ho cc yu t VIII, IX, X, XI, XII, v s kt tp tiu cu. Nh vy, mt khi thrombin chnh thnh, n s khi pht s iu ho ngc dng tnh lm nhiu thrombin c to ra hn na v qu trnh ngmu tip tc pht trin cho n khi c mt c ch ngn chn n li.
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S 3: S hnh thnh prothrombinase theo con ng ni sinh

3.3. Giai on thnh lp fibrin v cc mu ng

Thrombin cng vi Ca2+ chuyn fibrinogen thnh phn t fibrin n phn. Cc fibrin n phn ny ni vi nhauto thnh cc si fibrin t hnh thnh mng li ca cc mu ng. Lc u cc cu ni gia cc fibrin l cu ni

hydro lng lo nn cc mu ng yu, d tan r. Sau vi pht, nh s c mt ca yu t n nh fibrin (yu t XIII, chot ho bi thrombin) cc cu ni ng ho tr thay th cu ni hydro, ng thi c thm cc dy ni cho gia cc sfibrin k cn to nn mng li fibrin bn vng. Mng li ny giam gi cc t bo mu, tiu cu, huyt tng to nncc mu ng.

ngha: Cc mu ng bt thnh mch tn thng ngn cn mt mu.

Trong qu trnh ng mu, con ng ngoi sinh v ni sinh c khi pht ng thi. Tuy nhin, con ngngoi sinh din ra nhanh hn. N ch cn 15 giy, trong khi con ng ni sinh phi cn 1-6 pht gy ng mu.

Sau khi c hnh thnh 20-60 pht, cc mu ng co li v tit ra mt cht dch gi l huyt thanh. Nh vy,huyt thanh khc huyt tng ch l mt i cc yu t ng mu.

Tiu cu b giam gi trong cc mu ng ng vai tr quan trng trong vic co cc mu ny, nh vo cc proteinco nh thrombosthenin, actin v myosin. Tiu cu dnh vi cc si fibrin nn khi co li chng lm cc si ny cng ncht vi nhau. Cc tiu cu ny cn tip tc tit yu t n nh fibrin lm tng cng cc cu ni gia cc si fibrin kcn. Ngoi ra, s co ny cn c thc y bi thrombin v bi Ca 2+ c tit ra t cc kho d tr trong tiu cu. Cucng, cc mu ng tr thnh mt khi nh hn v c hn.

ngha: S co cc mu ng ko cc b ca thng tn mch mu st vo nhau nn cng lm vt thngc bt kn hn v n nh c s chy mu.

4. Tan cc mu ng - S hnh thnh m x

Mt khi cc mu ng c hnh thnh, n din tin theo 2 cch sau:
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- Cc cc mu ng hnh thnh ti vt thng nh ca thnh mch s b xm ln bi cc nguyn bo x, rhnh thnh nn t chc lin kt gip lin so vt thng.

- Cc cc mu ng ln hn hoc cc mu ng trong lng mch s b tan ra di tc dng ca h thngtan mu.

Hin tng tan cc mu ng din ra nh sau: khi cc mu ng c hnh thnh, plasminogen cng b giam gibn trong n. Di tc dng ca yu t hot ho plasminogen t chc ( t-PA), plasminogen s chuyn thnh plasmin ctc dng tiu protein. Plasmin s tiu hu cc si fibrin cng nh mt s yu t ng mu v lm cc mu ng tan ra. tPA c t chc tn thng hoc t bo ni mc tit ra khong 1 ngy (hoc mun hn) sau khi cc mu ng chnh thnh. Ngoi ra, thrombin v yu t XIIa cng ng vai tr quan trng trong vic hot ho plasminogen thnhplasmin.

ngha: S tan cc mu ng gip dn sch cc cc mu ng trong t chcv ti thng mch mu, to iukin lin so. c bit n gip ly i cc huyt khi nh trong mch mu nh trnh thuyn tc mch.

5. Mt s ri lon cm mu

5.1. Thiu vitamin K

Vitamin K rt cn cho s tng hp cc yu t ng mu II, VII, IX, X ti gan. V vy khi thiu ht vitamin K s gyxut huyt.

5.2. Bnh Hemophilia (bnh a chy mu)

Do thiu cc yu t ng mu VIII (Hemophilia A); IX (Hemophilia B). y l bnh di truyn qua nhim sc th XBnh nhn b xut huyt sau chn thng, c khi l chn thng rt nh khng nhn bit c.

5.3. Gim tiu cu

Thng gp l bnh gim tiu cu nguyn pht (v cn). Xut hin nhiu nt xut huyt trn ton c th.

5.4. Huyt khi

Gy thuyn tc mch. Thng gp trong x va mch mu, nhim trng, chn thng, hoc mu chy chm.

5.5. ng mu ri rc trong lng mch

Do s hin din ca cc m cht hoc tn thng trong c th; hoc c th gp trong sc nhim khun (do vkhun hoc ni c t ca n). c trng ca bnh l triu chng chy mu do cc yu t ng mu b s dng trongqu trnh ng mu, khng cn duy tr cm mu.

sinh lÝ hỌc vỀ mÁu

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