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991.
ABSTRACT— The localization of the cholestatic factor (CF) was immunocylochemically investigated in liver biopsy specimens obtained from patients with various liver diseases. CF was detected in seven of nine patients with drug-induced liver injury, three of four with acute viral hepatitis, three of five with alcoholic liver injury and in the two patients with autoimmune hepatitis. Fourteen of these 15 CF-positive patients had jaundice in their clinical courses. CF was stained diffusely in the cytoplasm of hepatocytes throughout the lobules in a granular pattern. Electron-microscopically, it was localized on the ribosomes and polysomes as well as on the filamentous structures around the bile canaliculi. However, CF was not detected in liver specimens from normal controls and patients with primary biliary cirrhosis and extrahepatic biliary obstruction. These findings suggest that CF plays an important role in intrahepatic cholestasis in various liver diseases.  相似文献   
992.
Neonatal mice (CR:NIH:S) were infected with a cloned human isolate of Giardia lamblia (GS/M-83-H7) and the surface antigens of the intestinal trophozoites, as well as the cellular and humoral immune responses, were analysed during the course of infection. Infections in mice peaked 2-3 weeks after inoculation and were self-cured by day 42 post-infection (p.i.). The proportion of trophozoites expressing the Mr 72,000 surface antigen of the initial inoculum had decreased by day 12 and approached zero by day 22 p.i., similar to infections in humans. The predominant parasite-specific humoral response was an IgM- and IgG-isotype directed to the original Mr 72,000 surface antigen as well as other antigens. T-lymphocytes (predominantly LY4(CD4)+) isolated from Peyer's patches 12 days p.i. and later showed a significant proliferative response to Giardia lamblia antigens. Spleen and lymph node cells showed no lymphoproliferative response. T-cell blot analysis revealed the presence of dominant T-cell epitopes in the areas of Mr 200,000-75,000 and less than 50,000 polypeptides. No response was demonstrated in the Mr 72,000 region (migration site of the major surface antigen), suggesting T-cell dependent mechanisms are most likely not responsible for the surface antigen switch which occurred during the course of infection. This model infection can be used to study the role of immunological mechanisms in Giardia lamblia variant antigen switching and in the control of infections.  相似文献   
993.
杨煌  王昕 《地方病通报》1990,5(1):15-19
用RIP对感染鼠疫菌的黄胸鼠等5种鼠类血清和脏器进行测定,结果表明脏器可检出F1体:一般情况,检出菌及IHA阳性标本难于查出抗体,而检出F1抗体者又难于培养出鼠疫菌:血清抗体阳性率及滴度与鼠疫菌攻击量无相关关系而与感染率有一定关系。  相似文献   
994.
Vaccination of cattle with midgut membrane (GM) antigen derived from the cattle tick, Boophilus microplus, infected with the adjuvant Quil A, resulted in significant increases in total immunoglobulins, mainly in the IgG1 and IgG2 fractions of the serum. Analysis of the anti-GM antibody levels of vaccinated cattle showed that the levels of IgG, IgG1 and complement-fixing antibodies were significantly correlated to protection against infestation with cattle ticks. Anti-GM antibodies of the IgG2 and IgM isotype were not correlated to protection against infestation with cattle ticks. Anti-GM antibodies fixed complement (C') in the presence of GM, larval membrane antigen and live, midgut cells, but not in the presence of live, larval cells. Anti-GM antibodies were able to fix C' equally well in the presence of GM antigen and live, midgut cells. None of the antigens tested activated the alternate pathway of complement under the conditions tested. Levels of anti-GM IgG1 antibodies were used to develop a regression model for predicting levels of protection against infestation with cattle ticks in vaccinated cattle.  相似文献   
995.
Microglial polarization to the anti-inflammatory M2 phenotype is essential in resolving neuroinflammation, making it a promising therapeutic strategy for stroke intervention. The actin cytoskeleton is known to be important for the physiological functions of microglia, including migration and phagocytosis. Profilin 1 (PFN1), an actin-binding protein, is involved in the dynamic transformation and reorganization of actin. However, the role of PFN1 in microglial polarization and ischemia/reperfusion injury is unclear. The role of PFN1 on microglial polarization was examined in vitro in BV2 microglial cells subjected to oxygen-glucose deprivation/reoxygenation (OGDR) and in vivo in male mice after transient middle cerebral artery occlusion (MCAO). Knockdown of PFN1 inhibited M1 microglial polarization and promoted M2 microglia polarization 48 hr after OGDR stimulation in BV2 cells and 7 days after MCAO-induced injury in male mice. RhoA/ROCK pathway was involved in the regulation of PFN1 during microglial polarization. Knockdown of PFN1 also significantly attenuated brain infarcts and edema, improved cerebral blood flow and neurological deficits in MCAO-injured mice. Inhibition of PFN1 effectively protected the brain against ischemia/reperfusion injuries by promoting M2 microglial polarization in vitro and in vivo.  相似文献   
996.
背景:在骨关节炎的发病过程中有大量炎症因子产生,针对炎症因子的抗体最近成为了研究热点.目的:概述治疗骨关节炎单克隆抗体的最新研究进展,为临床治疗骨关节炎提供参考.方法:利用计算机检索CNKI、万方、PubMed及Web of Science数据库2006年1月至2020年5月的相关文章,检索词为骨关节炎,单克隆抗体,...  相似文献   
997.
应用胃癌单抗ID1-2对833例内窥镜活检组织进行了免疫学荧光检查,胃癌阳性检出率为81.6%:胃溃疡为32.7%;肠化生性蒌缩性胃炎为40.0%;食管和结肠腺癌分别为60.0%和62.5%,与单纯性萎缩性胃炎和浅表性胃炎的阳性检出率相比有非常显著的差异(P<0.01)。表明ID1-2单抗可用于检测活检粘膜组织中的癌细胞以及具有癌细胞相关抗原的癌前病变组织,如果与内窥镜及常规病理学检查联合应用,将可进一步提高早癌的阳性检出率。  相似文献   
998.
本文应用人血浆纤维结合蛋白免疫BALB/c小鼠,经细胞融合制备出一组(5株)人血浆纤维结合蛋白的单克隆抗体(HIFn1-5)。经免疫酶标和免疫组化检测,这组单抗仅特异地与人血浆纤维结合蛋白结合,而与血浆中的其它大分子糖蛋白如纤维蛋白原、凝血酶敏感蛋白和胶原等均无明显的交叉反应。与多种器官、组织的间质可发生特异性反应,而与组织中的细胞则无反应。间接免疫荧光测定,这组抗体与正常人的造血细胞及某些造血细胞系和部分白血病病人的细胞均无交叉反应。竞争试验的结果表明,这组抗体(除HITn5外)识别的抗原位点十分相近。通过双抗体夹心ELISA方法,测定了17例正常人血浆纤维结合蛋白,其平均含量为557±154mg/L。  相似文献   
999.
A protamine sulphate (PS) pretreated solid phase coated with different amounts of dsDNA has been used to develop a sensitive, specific and reproducible anti-dsDNA ELISA. Using low concentrations of a dsDNA coat 50% of SLE sera were found to be positive and false positive reactivity due to anti-PS reactivity was found in 3/40 patients with other auto-immune diseases (OAID). In contrast, when PS was saturated with higher concentrations of dsDNA 80% of SLE sera were detected, the reproducibility of the results was better and anti-PS reactivity of OAID patients with an anti-PS reactivity disappeared. The sera of three other OAID patients contained low avidity anti-dsDNA, measured after a salt elution step in the ELISA procedure, and 2/60 patients with non-auto-immune disease exhibited a false positive anti-dsDNA reactivity since they reacted with the solid phase even in the absence of PS and dsDNA. Thus an ELISA procedure using a PS pretreated solid phase permits the sensitive, specific and reproducible measurement of anti-dsDNA antibodies only if a high concentration of dsDNA is coated on the PS and appropriate controls are performed.  相似文献   
1000.
An immunoblotting procedure is described which makes it possible to screen multiple blood samples for the presence of glycophorin and band 3 variant forms with altered electrophoretic mobility. The procedure can be simplified by using whole red blood cell hemolysates instead of membranes for SDS-polyacrylamide gel electrophoresis. The use of hemolysates also has the advantage that antigens sensitive to proteolysis are not degraded in vitro. The same nitrocellulose blots were used for immunoenzymatic detection of glycophorins with a set of anti-glycophorin monoclonal antibodies, and for autoradiographic detection of band 3-derived bands with 125I-labeled anti-band 3 monoclonal antibody. The screening of 157 Caucasian blood samples revealed the presence of a slower-migrating form of band 3 in seven cases and variant glycophorin in one case. The variant glycophorin exhibited the features of hybrid glycophorin of B-A type.  相似文献   
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