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31.
C.L. Richardson W.P. Tate S.E. Mason P.A. Lawlor M. Dragunow W.C. Abraham 《Brain research》1992,580(1-2):147-154
Expression of the immediate early gene zif/268 (also termed NGFI-A, Krox 24, TIS8 and Egr-1) was investigated in awake rats following various long-term potentiation (LTP) induction protocols.zif/268 mRNA (Northern blots) and protein (immunohistochemistry) levels sharply increased following LTP, and followed a time course characteristic of other immediate early genes. When measured across 3 tetanization protocols known to produce differing degrees of LTP persistence,zif/268 induction was found to be more highly correlated with LTP duration than with the magnitude of initial LTP. These data support the hypothesis that the immediate early gene zif/268 plays a role as a third messenger in the cascade of cellular and nuclear events that govern the persistence of LTP. 相似文献
32.
Over the past two decades, a number of Canadian paediatric academic programs, previously operated as separate hospitals, have been integrated into larger teaching hospitals or regional health authorities. The present article describes the recent experience of the Children’s Hospital of Western Ontario within the London Health Sciences Centre (London, Ontario) to illustrate the potential deleterious effects of planning, system and program changes in a large academic hospital without child health input at the executive decision-making level. The vision of the London Health Sciences Centre Executive Leadership Team and Board of Directors was divergent from that of the paediatric health care providers, which resulted in the resignation of a number of paediatric subspecialists and compromised the ability of the Department of Paediatrics to deliver paediatric care and educate future professionals. The present article highlights the need for the involvement of paediatric stakeholders in strategic planning in the hope that other academic centres can learn from this experience. 相似文献
33.
链置换式扩增检测羊水中巨细胞病毒DNA 总被引:2,自引:1,他引:1
目的:介绍一种简便快速准确检测羊水中CMV-DNA的改良PCR-链置换式扩增用于诊断胎儿先天感染CMV。方法,将组成套式PCR的外内两对引物按照一定比例(外:内=1:50-100)加在同一试管中一次扩增羊水和胎儿组织中CMV-DNA。结果:90例异常孕产史的孕妇羊水检测CMV-DNA,阳性率为38.9%(35/90),其中合并染色数目异常2例(47,XYY和47,XX,+21)(已引产)核型及染色 相似文献
34.
为探讨Graves眼病(GO)的发病机理,我们对新近发现的眼肌自身抗原及存在于GO患者血清的眼肌抗体进行了研究。血清取自18例正常人、18例活动性GO、10例无限征的Graves甲亢(GH)和3例桥本甲状腺炎(HT)患者。人眼肌膜蛋白经GO患者混合IgG亲和层析后进行SDS-聚丙烯酰胺凝胶电泳,显示分子量为45、28、55和64kD等蛋白条带。经正常人混合IgG亲和层析未能显示上述结果。Western印迹杂交虽然未能证实仅与患者血清作用的独特的眼肌抗原的存在,但64kD印迹存在于61%的GO、30%的GH、0%的HT患者,正常人仅22%阳性。抗64kD阳性率GO组明显高于对照组(P<0.05)。眼肌抗体(EMAb)特别是抗64kD抗体对于GO发病机理的作用值得进一步研究。 相似文献
35.
肿瘤发病率逐年上升,治疗手段日渐丰富,肿瘤患者的生存期得到明显延长,生活质量得到显著提高。因此,肿瘤和放疗、化疗后引起的并发症对患者生活质量及疾病预后的影响显得愈加重要。癌性发热作为肿瘤患者的常见并发症之一受到密切关注。临床实践发现西医治疗非感染性发热效果欠佳,而中医药优势相对显著,退热效果明显,不易反复,对患者生活质量及预后改善有利。 相似文献
36.
T. Tsuji R. M. Alborno M. Ehara T. Honda T. Miwatani 《European journal of epidemiology》1989,5(2):199-201
IgA protease produced by various strains of Haemophilus infuenzae can digest serum IgA and yield its fragments which can react with anti-IgA serum. We assayed IgA protease activity by detecting the digests of IgA by SDS-PAGE and immunoblotting. The digests were separated with SDS-PAGE, transferrend to nitrocellulose membranes and detected with anti- ( chain of human IgA, its Fab and its Fc) immunoglobulin conjugated peroxidases.Using this method, we can determine which type of IgA protease is produced by various of H. infuenzae strains. All the 20 strains isolated from respiratory tracts produced IgA protease. 相似文献
37.
Mahmoudi M Willgoss D Cuttle L Yang T Pat B Winterford C Endre Z Johnson DW Gobé GC 《The Journal of pathology》2003,200(3):396-405
Caveolae and their proteins, the caveolins, transport macromolecules; compartmentalize signalling molecules; and are involved in various repair processes. There is little information regarding their role in the pathogenesis of significant renal syndromes such as acute renal failure (ARF). In this study, an in vivo rat model of 30 min bilateral renal ischaemia followed by reperfusion times from 4 h to 1 week was used to map the temporal and spatial association between caveolin-1 and tubular epithelial damage (desquamation, apoptosis, necrosis). An in vitro model of ischaemic ARF was also studied, where cultured renal tubular epithelial cells or arterial endothelial cells were subjected to injury initiators modelled on ischaemia-reperfusion (hypoxia, serum deprivation, free radical damage or hypoxia-hyperoxia). Expression of caveolin proteins was investigated using immunohistochemistry, immunoelectron microscopy, and immunoblots of whole cell, membrane or cytosol protein extracts. In vivo, healthy kidney had abundant caveolin-1 in vascular endothelial cells and also some expression in membrane surfaces of distal tubular epithelium. In the kidneys of ARF animals, punctate cytoplasmic localization of caveolin-1 was identified, with high intensity expression in injured proximal tubules that were losing basement membrane adhesion or were apoptotic, 24 h to 4 days after ischaemia-reperfusion. Western immunoblots indicated a marked increase in caveolin-1 expression in the cortex where some proximal tubular injury was located. In vitro, the main treatment-induced change in both cell types was translocation of caveolin-1 from the original plasma membrane site into membrane-associated sites in the cytoplasm. Overall, expression levels did not alter for whole cell extracts and the protein remained membrane-bound, as indicated by cell fractionation analyses. Caveolin-1 was also found to localize intensely within apoptotic cells. The results are indicative of a role for caveolin-1 in ARF-induced renal injury. Whether it functions for cell repair or death remains to be elucidated. 相似文献
38.
目的建立分泌抗EPF(Early pregnancy factor,早孕因子)单克隆抗体的杂交瘤细胞株,纯化单抗并鉴定.方法用本实验室已纯化的早孕和肿瘤源性EPF作为抗原刺激Balb/c小鼠,用免疫后的小鼠脾细胞与同系小鼠骨髓瘤细胞(NS-1)融合,经4次克隆化,获得可稳定分泌抗EPF单克隆抗体的细胞株,注入Balb/c小鼠腹腔制备腹水型单抗,Protein-A亲和层析纯化,SDS电泳和Western-blot等方法分析纯化结果.结果融合后获得一株稳定分泌抗EPF抗体的细胞株(C3D11),克隆化后,获得稳定分泌抗EPF单克隆抗体的细胞株,将增殖后的细胞注射Balb/c小鼠腹腔获得腹水型单抗,以亲和层析法纯化,SDS-PAGE分析显示纯化后去掉了大部分杂蛋白,免疫印迹分析抗体纯度较高,与抗原匹配性良好.结论本研究制备的EPF单克隆抗体为特异性抗EPF抗体. 相似文献
39.
不对称PCR制备单链探针检测登革Ⅱ型病毒复制型RNA和复制中间体RNA 总被引:1,自引:0,他引:1
登革病毒是具包膜的单股正链RNA虫媒病毒 ,病毒的复制过程发生在感染细胞胞浆 ,复制型 (RF)RNA是病毒半保留复制的循环模板 ,复制中间体 (RI)RNA的合成则是病毒复制所必需的。经RT PCR获得的DNA模板进行不对称PCR扩增 ,当限制性引物终浓度为 2 5 0nmol L ,两引物比例为 1 0 0∶1时 ,即得到不对称PCR的预计单链和双链DNA产物。此单链产物用于标记探针进行核酸杂交。结果表明不对称PCR制备单链探针进行核酸杂交可用于检测病毒复制型RNA和复制中间体RNA的合成 相似文献
40.
Western blot 检测蛋白表达方法的改进 总被引:3,自引:0,他引:3
Western blot为常用的检测蛋白质的方法.其操作步骤较多,在抗体反应这一步骤中.常规方珐首先用靶蛋白特异性的非标记抗体与靶蛋白的抗原决定簇相结合.然后用Ⅰ-蛋白A或与辣根过氧化物酶耦联的抗免疫球蛋白抗体检测已结合上去的抗体,此法虽好,但有如下缺点:(1)信号放大有限.在蛋白质量少的隋况下无法得到满意结果, 相似文献