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991.
慢性乙型肝炎患者树突状细胞表型的研究 总被引:1,自引:0,他引:1
目的探讨慢性乙型肝炎患者外周血来源树突状细胞(Dendritic cell,DC)数量及表型的改变,并对其与肝功能、乙肝病毒复制水平的关系进行研究。方法检测37例慢性乙肝患者和21例健康人肝功能及血清HBV DNA水平,并提取外周血单个核细胞(Peripheral blood mononuclear cell,PBMC)进行体外诱导培养,促使其发育成DC,计数其数量并检测膜表面分子的变化。分析DC数量及表型与肝功能、乙肝病毒复制水平的关系。结果与正常对照组比较,慢性乙肝患者的树突状细胞数量明显减少(P〈0.05),且其膜表面分子CD83、CD86的表达均明显降低(P〈0.05)。在慢性乙肝患者中,DC数量、DC膜表面分子CD83和CD86与血清HBV DNA之间呈负相关关系,而与肝功能之间无明显相关关系。结论慢性乙肝患者体内存在DC数量减少及成熟障碍,这种改变与肝内炎症反应程度不相关,但与乙肝病毒(Hepatitis Bvirus,HBV)的复制水平呈负相关,提示DC参与慢性乙肝患者体内HBV的清除。 相似文献
992.
小儿慢性乙型肝炎外周血T细胞亚群和临床病理关系的研究 总被引:7,自引:0,他引:7
目的 探讨小儿慢性乙型肝炎细胞免疫功能与临床、病理的关系 ,了解其间的相关性。方法 研究对象为确诊的 94例 12岁以内慢性乙型肝炎住院患儿。常规检测血T细胞亚群等、血丙氨酸转氨酶 (ALT)水平、病毒学指标 ,并进行腹部B超、肝脏病理学检查。结果 有活动性肝脏病理炎症者CD4 CD8 升高 (P <0 0 5 ) ;女性比男性CD4 降低差异有非常显著意义 (P <0 0 1)、CD8 升高差异有显著意义 (P <0 0 5 )、CD4 CD8 降低差异有非常显著意义 (P <0 0 1) ;T淋巴细胞的异常改变与HBVDNA、PTA以及脾脏大小关系不明显。而各项观察的临床、病理指标与CD3 T淋巴细胞、B淋巴细胞均无明显相关性。结论 小儿慢性乙型肝炎患者机体存在细胞免疫功能失衡 ,其相关性表现在肝脏炎症损伤严重程度与T淋巴细胞功能的损伤有明显的相关性 ,女性对HBV的T淋巴细胞反应比男性更有利于清除HBV ,其预后及对抗病毒和免疫调节治疗反应较好。 相似文献
993.
Jeff Alexander Marie-France Del Guercio John D Fikes Robert W Chesnut Francis V Chisari Kyong-Mi Chang Ettore Appella Alessandro Sette 《Human immunology》1998,59(12):776-782
Using short term CTL lines derived from HLA A2/Kb transgenic mice and IFN-gamma release assays we demonstrate that the NS4.1769 epitope, is generated from natural processing of the NS4 antigen, and presented in the context of the A2/Kb molecules. Interestingly, T cell recognition of the naturally processed form of the NS4.1769 epitope was associated with significant IFN-gamma release, but no direct cytolytic activity. Epitopes of this phenotype might be of interest, in terms of therapy of chronic HCV infection by associating the benefit of localized lymphokine release with low or absent direct cytopathicity. 相似文献
994.
Yu Nakamura Masatoshi Takeda Hideo Suzuki Hideyuki Hattori Kunitoshi Tada Shiro Hariguchi Shigeo Hashimoto Tsuyoshi Nishimura 《Neuroscience letters》1991,130(2):195-198
Formalin-fixed paraffin-embedded hippocampal sections of brains with early-onset and late-onset Alzheimer's disease were studied immunohistochemically with antisera against cathepsin D and cathepsin B. In addition to the staining of neuronal perikarya, some of the senile plaques visualized by Bielshowsky silver staining and some of reactive astrocytes were positively stained with the antisera against cathepsin D and cathepsin B in brains with Alzheimer's disease. Abnormal localization of cathepsin D and cathepsin B immunoreactivity in neuronal perikarya was observed in brains with early-onset Alzheimer's disease. These findings demonstrate that the distribution of lysosomal proteases was altered in brains with Alzheimer's disease, suggesting the primary and/or secondary involvement of the lysosomal proteases in the pathological process of Alzheimer's disease. 相似文献
995.
Flow cytometric analysis of cell proliferation dynamics in the B cell compartment of the mouse 总被引:20,自引:0,他引:20
Using a method which allows simultaneous flow cytometric detectionof cell surface markers and 5-bromo-2'-deoxyuridine (BrdU) incorporation,the distribution and proliferative behavior of B lineage subpopulationswas studied in intact adult mice. In the bone marrow we coulddefine two subsets of B cells on the basis of differential expressionof the pan-B cell marker B220 and of membrane-associated µand immunoglobulin heavy chains. B220dullµ+– Bcells were found to emerge from rapidly dividing cells and probablyrepresent B cells recently generated from B220dullµ–pie-B cells. In contrast, oniy few, If any, of the B220brightµ++B cells were labeled with BrdU after a period of 8 days, suggestingthat these cells represent long-lived B cells residing in thebone marrow. Analysis of BrdU-Incorporation into splenic B cellsshowed that only 20% of these cells had gone through cell divisionduring the preceding 8 days. Almost none of the B cells in theperitoneum, a large fraction of which belongs to the Ly1 B subset,were labeled with BrdU over a period of 7 days in 8-month-oldanimals. 相似文献
996.
The caudate lobe of the liver 总被引:3,自引:0,他引:3
Y. Heloury J. Leborgne J. M. Rogez R. Robert J. Y. Barbin J. Hureau 《Surgical and radiologic anatomy : SRA》1988,10(1):83-91
Summary The caudate lobe of the liver is an independent segment straddling the right and left lobes of the liver. It is divided into 2 parts, right and left, indicated eternally by the caudate and papillary processes. It is now possible to unvestigate it by ultrasonography and computed tomography, allowing its surgical excision for tumoral disease of the superior biliary confluence.
Le lobe caudé du foie
Résumé Le lobe caudé du foie est un secteur indépendant à cheval sur les foies droit et gauche. Il est séparé en 2 parties droites et gauches, marquées extérieurement par les processus caudé et papillaire. Son exploration est actuellement possible (échographie et tomodensitométrie), ce qui autorise son exérèse chirurgicale (pathologie tumorale du confluent biliaire supérieur).相似文献
997.
Human umbilical cord blood, which in the past was discarded with the placental tissue,
provides a convenient source of fetal hemopoietic cells for scientific analysis and clinical use.
Cord blood cells are immature compared to analogous populations in adult peripheral
blood. Cord blood B lymphocytes display unique phenotypic and functional characteristics.
The antigens CD1C, CD38, CD5, and CD23, although normally expressed on only a small
percentage of circulating B cells in adults, are highly expressed on cord blood B cells. Recent
studies have demonstrated that whereas cord blood B cells are functionally naive, their
potential is similar to that of adult B cells if optimal T-cell help is available. Thus, the failure
of B-cell responses in cord blood is due to the T cells. The functional abnormalities of T cells
from newborns can be summarized as a dominance of the effects of TH0 cells. Thus, the
cytokines produced are immunosuppressive rather than mediating helper activity for B cells.
NK activity in cord blood is also depressed compared to that in adults. Cord blood is a very
rich source of hemopoietic progenitor cells. The spectrum of progenitors shows a predominance
of early progenitor cells when compared with bone marrow. These cells provide an
alternative source to adult bone marrow for stem cells to use for hemopoietic reconstitution
and as targets in the treatment of hereditary deficiencies by gene therapy. These features
make cord blood a unique research tool to investigate hemopoietic ontogeny and a unique
clinical tool for transplantation. 相似文献
998.
Spleen cells from a Lewis rat immunized with affinity-purified B10 anti-(T,G)-A-L antibody were fused with the non-secreting murine hybridoma SP2/0. Cell lines secreting monoclonal antibodies specific for mu- and kappa-chains, as well as an idiotope on anti-(T,G)-A-L antibodies, were isolated and characterized. The anti-mu and -kappa antibodies, are true anti-isotypes, reacting with sera from all strains of mice tested. The anti-idiotope antibodies recognize a determinant on antibodies binding a GT-containing epitope. The proportion of anti-GAT antibody bearing the idiotope varies markedly in different murine strains. A 1000-fold higher level of antibody from Igha mice than from Ighb and Ighe mice is required to give an equivalent inhibition of the idiotope-anti-idiotope reaction. Analysis of monoclonal antibodies expressing the idiotope indicates that the affinity of binding between idiotope and anti-idiotope can vary by as much as two orders of magnitude. Immunoadsorbants prepared with anti-idiotope antibody bind suppressor factor secreted by a GAT-specific T-cell hybridoma. 相似文献
999.
The pathogenesis of progressive bile duct loss in primary biliary cirrhosis remains unclear. In this study, the involvement of cellular senescence of biliary epithelial cells was examined in liver tissue samples from patients with primary biliary cirrhosis (n = 33), and compared with control diseased and normal livers (n = 83). In addition, cellular senescence was induced by oxidative stress in cultured mouse biliary epithelial cells. Biliary epithelial cells in small bile ducts in primary biliary cirrhosis, especially those in patients presenting with chronic non-suppurative cholangitis, frequently expressed senescence-associated beta-galactosidase, and senescence-associated p16(INK4) and p21(WAF1/CIP). In contrast, senescence-associated markers were rarely expressed in small bile ducts in control livers. The infiltration of myeloperoxidase-positive inflammatory cells into biliary epithelial cell layers was closely associated with the cellular senescence of biliary epithelial cells in early-stage PBC. Cellular senescence of cultured mouse biliary epithelial cells was induced by treatment with H2O2 via the p38MAPK-dependent pathway and nitric oxide-augmented H2O2-induced cellular senescence. Oxidative stress- and nitric oxide-mediated cellular senescence may be involved in bile duct lesions, which are followed by progressive bile duct loss in primary biliary cirrhosis. 相似文献
1000.
结核分枝杆菌Ag85B与IL-12基因真核共表达质粒的构建及表达 总被引:3,自引:1,他引:3
目的 :构建结核分枝杆菌Ag85B和鼠IL 12基因的共表达载体pBud85B IL12。方法 :将结核分枝杆菌Ag85B基因和鼠IL 12基因同时克隆入含多启动子的共表达载体pBudCE4 .1中 ,构建真核共表达质粒pBud85B IL12。以pBud85B IL12转染COS 7细胞 ,通过RT PCR及ELISA方法检测目的基因的表达。结果 :在COS 7细胞中同时可检测到Ag85B和IL12的表达。结论 :pBud85B IL12共表达质粒的成功构建 ,为对其免疫原性、免疫反应性及免疫保护作用的进一步研究奠定了基础 相似文献