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Angiogenesis and patency of blood vessels were analyzed qualitatively in solid CNS and peripheral tissue syngeneic, allogeneic, and xenogeneic grafts and in individual cell suspension grafts of astrocytes, fibroblasts, PC12, and three additional tumor cell lines placed intracerebrally in adult host mice. Postgrafting survival times were 1 day through 4 weeks. The patency of graft vessels was determined in sections from immersion-fixed tissues incubated to reveal the endogenous peroxidase activity of host red cells trapped within the lumen of blood vessels. Additionally, horseradish peroxidase (HRP) was administered intravenously to live hosts; HRP labels host brain and graft vessels on the luminal surface and reveals the presence or absence of a blood-brain barrier (BBB) within the grafts. The origins of blood vessels supplying solid tissue xenografts were identified immunohistochemically with primary antibodies against host (athymic AKR mice) and donor (fetal Lewis rats) major histocompatibility complex (MHC) class I. Blood vessels supplying solid CNS grafts at 1-7 days post-transplantation were identified ultrastructurally and possessed interendothelial tight junctional complexes; however, they were not perfused with either host blood or blood-borne HRP prior to 8 days. Graft vessels at 10 days were outlined consistently by peroxidase-positive red cells in immersion-fixed material and labeled with blood-borne HRP. These vessels provided a BBB to the circulating HRP and exhibited interendothelial tight junctions. Evidence of angiogenesis within solid anterior pituitary grafts and the variety of cell suspension grafts was obtained prior to 3 days post-transplantation in immersion-fixed preparations; the vessels, with the notable exception of those supplying astrocyte cell suspensions, failed to present a BBB to blood-borne peroxidase. Endothelia in the solid pituitary allografts and the PC12 cell grafts were highly fenestrated and exhibited open interendothelial junctions; those in the tumor and fibroblast cell grafts, for the most part, appeared nonfenestrated, and many possessed open interendothelial junctional complexes. Immunostaining for host and donor MHC class I revealed that donor blood vessels predominate over host vessels in CNS xenografts and supply pituitary xenografts exclusively; in both preparations, donor vessels were not identified within the host CNS. Because cell suspension grafts were derived from endothelia-free preparations grown in culture, blood vessels supplying these grafts were necessarily of host CNS origin and manifested a morphological transformation from a BBB to a non-BBB endothelium. The data suggest that angiogenesis in solid CNS grafts placed into the adult host CNS, compared to similarly placed solid peripheral tissue/cell suspension grafts, is not rapid.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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冠心病、高血压、心律失常等心血管疾病作为现代社会的多发病和常见病,已经引起医学界的广泛关注和高度重视。维吾尔医药基于维吾尔医药的特有理论和丰富的经验,借助现代医学先进的诊疗技术和科学手段,对部分常见的心血管疾病进行了大量的临床观察和深入的研究,取得了许多独具特色的成功经验和科研成果。我院在临床上自1991年开始应用玫瑰花口服液治疗心血管疾病,疗效显著。现仅在2005年治疗心血管疾病中随机抽样进行疗效观察。  相似文献   
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The importance of certain positive crossmatches (CM+) in kidney transplantation remains controversial. Fifty consecutive kidney transplants were performed across a CM+ between Jan. 1990 – April 1994. In 19 cases there was an isolated B-cell CM+ (Group I), in 24 an historic T-cell IgM CM+ (Group II) and in 7 an historic T-cell IgG CM+ (Group III). Comparing groups I:II:III: early acute rejection affected 32%, 42%, 57% of grafts; mean serum creatinine at 3 months was 166, 150, 229 umol/l (p<0.05); 1 yr graft survival was 95 per cent, 96 per cent, 71 per cent (p=0.09). In group III both graft losses were in the setting of an additional current B-cell CM+. Conclusions: Transplantation performed in either the presence of an isolated B-cell CM+ or in the presence of an historic T-cell IgM CM+ was associated with acceptable outcomes at 1 yr. An historic T-cell IgG CM+ was confirmed as a contraindication to transplantation in most circumstances, especially when coupled with a current B-cell CM+.  相似文献   
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目的研究新疆维吾尔族慢性胃炎患者HLA-DRB1等位基因与幽门螺杆菌(Hp)感染的关系。方法采用幽门螺杆菌分离培养技术检测33例维吾尔族慢性胃炎患者幽门螺杆菌感染情况,采用PCR-SSP检测HLA-DRB1*0405、HLA-DRB1*08、HLA-DRB1*12等位基因,并与36例汉族慢性胃炎患者进行比较。结果1)新疆维吾尔族慢性胃炎患者Hp阳性率(78.8%)显著高于汉族慢性胃炎患者(58.3%)(P〈0.05);2)维吾尔族、汉族慢性胃炎患者Hp感染与HLA-DRB1*0405、HLA-DRB1*08、HLA-DRB1*12等位基因无相关性(P〉0.05)。结论1)维吾尔族慢性胃炎患者Hp感染率高于汉族慢性胃炎患者;2)维吾尔族、汉族慢性胃炎患者Hp感染与HLA-DRB1*0405、HLA-DRB1*08、HLA-DRB1*12等位基因无关。  相似文献   
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We have determined the frequency of heterozygosity of the short arm of chromosome 17 in 20 cervical tumours using the highly polymorphic probe pYNZ22. Only 25% of the tumours were heterozygous at this locus. This is significantly lower than the level of 86% heterozygosity for this locus in the general population indicating that loss of one allele occurs in cervical cancer. Heterozygosity for a locus on the long arm of the same chromosome showed no significant difference between the tumours and the general population indicating that genetic loss was confined to the short arm of the chromosome. The analysis of premalignant lesions showed 70% of patients were heterozygous suggesting that loss of material from the short arm of chromosome 17 took place at a late stage in tumour development. This report confirms predictions made from previous karyotypic analysis and is the first indication of allele loss on the short arm of chromosome 17 in cervical cancer.  相似文献   
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Nitric oxide (NO), originally identified as the mediator of endothelial-dependent relaxation of vascular smooth muscle, is now known to also have cytotoxic effects under certain conditions. Thus, we have investigated the effects of inhibition of NO synthesis on ischemia/reperfusion injury in the rabbit rectus femoris muscle. Three and a half hours of ischemia and 24 hours of reperfusion resulted in a 56% loss of viability. In muscles receiving an infusion of the nitric oxide synthase inhibitor, L-NIO (30 μM), the loss of viability was reduced to 15%. Post-ischemic blood flow was increased in muscles receiving a saline infusion, whereas there was a marked decrease in blood flow for at least the first 60 minutes of reperfusion in muscles treated with L-NIO (30 μM). The increase in myeloperoxidase levels (indicative of neutrophil accumulation) following 24 hours of reperfusion was attenuated with L-NIO infusion by approximately 50% and the reperfusion-induced edema was also attenuated in L-NIO treated muscle. These findings suggest that endogenous NO production during ischemia/reperfusion injury may be deleterious to muscle survival. © 1994 Wiley-Liss, Inc.  相似文献   
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