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1.
非创伤缺血预处理对大鼠缺血再灌注心肌的作用   总被引:5,自引:1,他引:4  
目的:确定非创伤性缺血预处理对大鼠缺血/再灌注(I/R)心肌损伤是否具有对抗作用,以扩展缺血预处理的实际应用.方法:采用非创伤性下肢缺血预处理及经典缺血预处理的动物模型,比较两种处理方法对I/R心肌损伤的效应.实验动物分4组:正常对照组(NC,n=8),开胸旷置50 min;缺血/再灌注组(I/R,n=12),结扎冠脉30 min,再灌注20、180 min;经典缺血预处理组(C-IPC,n=12),按经典Murry法复制;非创伤性下肢缺血预处理组(N-WIPC,n=12),捆绑双下肢5 min,松开5 min,反复4次后,阻断冠脉30 min,再灌20、180 min.以左室功能,心肌梗塞范围,血清肌酸激酶(CK)及心肌组织丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性为观察指标.结果:与I/R组相比,N-WIPC组与C-IPC组均显著缩小I/R后的心肌梗塞范围(P<0.01);明显恢复I/R后的左室功能(P<0.05,0.01);减轻自由基对心肌的损害:血清CK,心肌MDA含量显著降低(P<0.01).N-WIPC组还使心肌SOD活性增高(P<0.05).结论:非创伤性下肢缺血预处理与经典缺血预处理可诱发同等强度的心肌预处理效应.  相似文献   

2.
目的观察不同 pH值HEPES-KH复灌液对未成熟心肌间质的影响。方法采用Langen dorff离体灌注模型 ,分为3组 :正常对照组(NC ,n=8) ,仅灌注pH7.4HEPES-KH液90min;缺血/再灌组(I/R ,n=8) ,灌流20min后缺血60min ,用 pH7.4HEPES -KH液恢复灌注30min ;酸性灌注组 (E ,n=8) ,缺血60min后 ,先用pH6.8HEPES-KH液灌注5min,然后换成 pH7.1灌注5min ,最后恢复pH7.4灌注20min。以心脏舒张功能指标、心肌羟脯氨酸 (HP)及血清内皮素 (ET)含量作为观察指标。结果E组在心功能恢复、HP含量方面高于I/R组 (P<0.05),ET含量低于I/R组(P<0.05)。结论 pH反常是I/R损伤的重要发病机制 ,复灌初期应用梯度酸性复灌液有助于未成熟心肌间质的保护。  相似文献   

3.
目的:探讨大鼠心脏缺血预处理(IPC)中金属硫蛋白(MT)的变化。方法:采用经典的IPC模型,与I/R心肌损伤比较。实验动物分为3组:假手术组(n=6),开胸旷置2 h 20 min;缺血/再灌注组(n=12),结扎左冠状动脉前降支40 min,再灌注1 h 40 min;经典IPC组(n=12),按经典的Murry法复制。以心肌MT的含量,心肌梗塞范围,心肌组织丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性为观察指标。结果:IPC组心肌MT含量明显高于I/R组(P<0.01),心肌MDA含量明显低于I/R组(P<0.01),心肌SOD活性明显高于I/R组(P<0.01)。经直线相关分析,IPC组心肌MT含量与SOD活性呈正相关(r=0.91, P<0.01),与MDA含量呈负相关(r=-0.92, P<0.01),IPC组心肌梗塞范围明显小于I/R组(P<0.05)。结论:缺血预处理能促进大鼠心肌MT合成,MT可能参与IPC的保护效应。  相似文献   

4.
大鼠在体心脏缺血后处理模型的建立与优化   总被引:3,自引:1,他引:3  
孙胜  赵秀梅  刘秀华 《中国微循环》2007,11(6):401-403,413
目的建立并优化大鼠在体心脏缺血后处理(I-postC)模型。方法采用冠状动脉左前降支垫扎球囊法建立在体心脏I-postC模型,健康雄性SD大鼠随机分为7组(n=8):缺血/再灌注(I/R)组(冠状动脉左前降支缺血45min/再灌注2h)、缺血预处理(IPC)组(I/R前先行3轮缺血5min/再灌注5min处理)、I-postC组(包括4个亚组,于冠脉缺血45min后先进行3或4轮再灌注30s/缺血30s或再灌注60s/缺血60s后处理后再进行冠脉再灌注)以及假手术(sham)组。氯化三苯四氮唑(TTC)法测定心肌梗死面积,试剂盒检测血浆乳酸脱氢酶(LDH)和心肌组织超氧化物歧化酶(SOD)活性。结果I/R引起明显的心肌梗死和组织损伤,采用冠状动脉左前降支垫扎球囊法进行I-postC可以显著减少I/R后心肌梗死面积,尤以3或4轮再灌注30s/缺血30s组保护作用明显,其梗死区占缺血区百分比分别比I/R组下降30.26%和58.81%(P分别<0.05),与IPC保护效果相近。结论I-postC可以减轻心肌I/R损伤,其中4轮再灌注30s/缺血30s诱导的I-postC在限制心肌梗死面积方面作用最明显,是理想的大鼠在体心脏I-postC模型。  相似文献   

5.
丹参酮ⅡA磺酸钠对家兔缺血预处理心肌保护作用的影响   总被引:9,自引:0,他引:9  
目的观察丹参酮ⅡA磺酸钠对家兔缺血预处理心肌保护作用及血浆和心肌组织NO代谢产物含量的影响。方法家兔24只 ,随机分为心肌缺血再灌注组 (IR ,n=8)、缺血预处理组 (IPC,n=8)和丹参酮ⅡA磺酸钠联合缺血预处理组 (DS-201 IPC,n=8) ;TTC染色测定梗塞面积 ;HE染色病理组织学观察。采用硝酸还原酶法检测缺血前、缺血后30min和再灌注30min三个时点血浆及心肌组织NO代谢物含量。结果 (1)TTC染色称重结果显示 ,IPC组心肌梗死面积 (梗死区重量/缺血区重量为9.54±5.79)明显小于IR组 (梗死区重量/缺血区重量为35.48±3.84Δ ,P<0.05) ,DS201 IPC组心肌梗死面积 (梗死区重量/缺血区重量为5.66±1.6)明显小于IPC组心肌梗死面积 (P<0.05)。病理学检测显示 ,与IR组相比 ,IPC组组织损伤程度明显减轻。与IPC组相比 ,DS201 IPC组组织损伤程度明显减轻。 (2)缺血30min和再灌注30minIR组血浆NO代谢产物[缺血30min(11.2±3.9)μmol/L,再灌注30min(11.6±5.6)μmol/L]和心肌组织NO代谢产物[再灌注30min末(23.0±5.3)μmol/mg]显著低于缺血前[血浆NO代谢产物为(28.5±6.8)μmol/L,心肌组织NO代谢产物为(49±18.3)μmol/mg](P<0.05) ;缺血30min和再灌注30minIPC组血浆NO代谢产物[缺血30min(19.5±2.5)μmol/L,再灌注30min(1  相似文献   

6.
刘剑刚  张蕾  史君鹤  张大武  史大卓 《微循环学杂志》2011,21(3):4-7,11,88,90,93
目的:观察缺血预适应(IPC)、缺血后适应(IPOC)对大鼠心肌组织缺血/再灌注(I/R)损伤后Toll样受体(TLR)及下游炎症因子的影响。方法:SD大鼠60只,通过SPSS软件随机分为假手术组(冠状动脉前降支下置线不结扎,n=15);I/R组(冠状动脉前降支结扎30min,再灌注60min,n=15);IPC组(冠状动脉前降支3次3min/5min的缺血/再灌注循环,然后结扎30min后,再持续灌注60min,n=15);IPOC组(冠状动脉前降支结扎30min,3次10s的缺血/再灌注循环,再持续灌注60min,n=15)。实验结束后测定大鼠血清肌酸激酶同工酶(CK-MB)和肌钙蛋白T(cTNT)水平;氯化硝基四氮唑兰(NBT)染色测定大鼠左室心肌梗死面积;免疫组织化学法测定心肌组织TLR-2、4的表达;酶联免疫吸附法测定心肌组织白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、单核细胞趋化蛋白-1(MCP-1)和肿瘤坏死因子-α(TNF-α)的含量。结果:与I/R组比较,IPC组、IPOC组大鼠血清CK-MB和cTNT水平显著降低(P<0.01),心肌梗死面积显著减小(P<0.01),心肌组织TLR-2、4表达和炎症因子IL-6、IL-1β、MCP-1、TNF-α含量显著下降(P<0.05,P<0.01);与IPC组比较,IPOC组减小I/R大鼠心肌梗死面积,降低血清CK-MB及心肌组织IL-6等作用和IPC组无显著差异(P>0.05)。结论:IPOC与IPC同样具有减轻心肌I/R损伤程度和缩小心肌梗死范围等作用,抑制TLR-2、4的表达可能是其保护I/R心肌的一个重要途径。  相似文献   

7.
孙贤林  张静  张新金 《微循环学杂志》2006,16(3):28-30,F0003
目的:观察延迟缺血预适应(IschemicPreconditioning,IPC)对兔在体心脏缺血再灌注(Ischemia/Reperfusion,I/R)损伤的保护作用。方法:方法18只兔随机分为3组:假手术组(CON组,n=6),缺血再灌注组(I/R组,n=6),预适应组(IPC组,n=6)。采用免疫组化方法检测诱导型一氧化氮合成酶(iNOS)及内皮型一氧化氮合成酶(eNOS)在心肌及冠状动脉内皮中的表达情况。结果:IPC组的梗死面积明显小于I/R组。在心肌中,IPC组iNOS表达明显高于I/R组与CON组,而eNOS无显著性差异。在内皮中,IPC组eNOS表达明显高于I/R组,与CON组无显著性差异,而iNOS均无表达。结论:延迟缺血预适应能缩小兔缺血再灌注后心肌梗死面积。  相似文献   

8.
 目的:观察银杏达莫注射液预处理对大鼠离体心脏缺血/再灌注损伤的影响,并探讨其可能的作用机制。方法:SD雄性大鼠40只随机分成5组(n=8):正常对照(NC)组、缺血/再灌注(I/R)组、缺血预处理(IPC+I/R)组、银杏达莫注射液预处理(GD+I/R)组和银杏达莫+氯化镧预处理(GD+LaCl3+I/R)组。观察各组相同时点(预灌30 min稳定点,缺血30 min,再灌5 min、30 min、60 min)的心功能指标,包括心率(HR)、左室收缩压(LVSP)和室内压变化速率(±dp/dtmax),同时收集各时点冠脉流出液,检测其中乳酸脱氢酶(LDH)和肌酸激酶(CK)活性。实验结束后检测心肌线粒体Ca2+浓度和α-酮戊二酸脱氢酶(α-OGDH)含量。结果:与I/R组比较,IPC+I/R组和GD+I/R组在心脏再灌注期各项心功能指标均得到改善(P<0.05);心肌LDH和CK的释放量降低(P<0.01);线粒体内Ca2+超载降低(P<0.01),且线粒体内α-OGDH含量升高(P<0.05);而GD+I/R组中银杏达莫对心肌的保护作用被LaCl3抑制(P<0.05)。结论:银杏达莫可能通过抑制钙超载、增强线粒体酶活性以稳定线粒体能量代谢,从而缓解缺血/再灌注诱导的心肌细胞损伤。  相似文献   

9.
目的通过心肌酶学等检测指标评估异氟醚、卡托普利联合预处理对缺血再灌注的心肌保护作用。方法新西兰大白兔48只随机分成6组(n=8),假手术组(S组)仅开胸分离冠状动脉左前降支;缺血组(I/R组):缺血30 min后再灌注120min;缺血预处理组(IPC组):缺血5 min、再灌注5 min循环3次后处理同缺血组;异氟醚组(I组):给予1.1%异氟醚吸入30 min洗脱15 min后处理同I/R组;卡托普利组(C组)24 h给予卡托普利片25 mg/kg后处理同I/R组;联合预处理组(I+C组)24 h给予卡托普利片25 mg/kg后处理同I组。各实验组分别检测不同时点的心肌酶和心肌肌钙蛋白I(cTnI)的变化,在再灌注结束即刻取血检测丙二醛(MDA)浓度及超氧化物歧化酶(SOD)活性。结果各处理组心肌酶学指标均高于S组(P<0.05或P<0.01),但增高程度低于I/R组(P<0.05),IPC组和I+C组又较I组和C组低(P<0.05)。各组MDA均增高,SOD降低(P<0.01),但与I/R组比,各药物处理组MDA降低,SOD较高(P<0.01)。IPC组和I+C组MDA和SOD分别较I组和C组降低和升高(P<0.05)。结论异氟醚、卡托普利联合预处理明显减轻兔心肌缺血再灌注心肌酶学改变,较单独应用异氟醚、卡托普利预处理的心肌保护作用增强,其效果与缺血预处理相似。  相似文献   

10.
目的探讨诱导金属硫蛋白(MT)在未成熟心肌中的表达对缺血/再灌注未成熟心肌细胞功能的影响.方法采用Langendorff离体灌注模型,大白兔分为4组:对照组(C,n=9),腹腔注射蒸馏水0.3ml,按注射后时间12、24、和48 h取离体心脏,灌注KH液15 min转为工作心15 min,全心停灌45min,恢复灌注15 min改为工作心30 min;E12h组(n=6)、E24h组(n=6)、E48h组(n=6)各组分别按腹腔注射3.6%ZnSO4(1.5 ml/kg)后12、24和48 h取离体心脏,常规建立Langendorff灌注模型.方法同C组.以心肌细胞中MT含量、CK和LDH漏出率、ATP含量、心肌细胞内Ca2 含量、心肌线粒体Ca2 -ATPase活性及其Ca2 含量、心肌线粒体合成ATP能力[ATP]m作为观察指标.结果腹腔注射ZnSO4后12 h MT开始表达,24h达高峰,48 h仍在高表达水平.MT含量在E24h、E48h组与C、E12h组比较明显增高;E24h、E485h组ATP含量优于C组和E12h组(P<0.05),CK、LDH漏出率均低于C组和E12h组(P<0.05),心肌线粒体Ca2 -ATPase活性、[ATP]m均优于C组和E12h组(P<0.01),心肌细胞内Ca2 含量、心肌线粒体Ca2 含量低于C组和E12h组(P<0.01).结论腹腔注射ZnSO4可诱导心肌MT长时间表达,MT可减轻未成熟心肌细胞缺血/再灌注损伤.  相似文献   

11.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

12.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

13.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

14.
15.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

16.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

17.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

18.
Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.  相似文献   

19.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

20.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   

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