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41.
42.
The expression of CD45R on mouse T cells has been studied. This antigen is expressed on the two higher molecular weight bands of CD45 (or T200) and in mouse it is currently used as a marker of B cells (B220). Here we confirm that CD45R is expressed on some mouse T cell clones. We show that a small but measurable proportion of mouse spleen and peripheral blood lymphocyte T cells gives positive immunofluorescence with B220. Also CD45R-specific antibodies increase the proliferation response to phytohemagglutinin up to 3-fold, thus confirming that CD45R molecules transduce a signal into mouse T cells. 相似文献
43.
Paolo Lionetti Jo Spencer Emma J. Breese Simon H. Murch Jacqueline Taylor Thomas T. Macdonald 《European journal of immunology》1993,23(3):664-668
Staphylococcus aureus enterotoxin B (SEB) was added to explants of fetal human intestine in organ culture or administered into the lumen of fetal small intestine prior to culture. Both routes produced a massive increase in lamina propria T cells expressing Vβ33, and to a lesser extent, those expressing Vβ5 and Vβ12. SEB-activated lamina propria T cells produced interleukin-2 and interferon-Y and T cell activation was accompanied by tissue damage, which was inhibited by FK506. 相似文献
44.
The goal of this study was to investigate the factors responsible for the low subitizing limit of cerebral palsied (CP) children. For this purpose, 44 CPs were tested on two tasks involving the rapid recognition of dot configurations. The answer was either a number (subitizing task) or the name of a pattern (pattern recognition task). The CPs were compared to controls of the same age. All children were evaluated for visual and visuospatial short-term memory. The results showed that CPs with a low subitizing limit did not do better with a canonical arrangement than the random one, were impaired to the same extent on the pattern recognition task as on the subitizing task, and had a short visuospatial short-term memory span. These results suggest that the low subitizing limit of CPs stems from a (non-number-dependent) lesser capacity to perceive a dot configuration as a gestalt. A low subitizing limit was almost always associated with a right-hemisphere lesion. 相似文献
45.
Tetraspanins are a large superfamily of cell surface membrane proteins characterised by their four transmembrane domains. They are expressed in a wide variety of cell types and have functional roles in processes, such as cellular adhesion, motility, activation and tumour invasion. Leukocytes express =20 tetraspanin proteins on their surface. Tetraspanins have an exceptional ability to interact with a diverse array of important proteins, such as integrins, immunoreceptors and signalling molecules. They are thought to organise a novel type of cell surface membrane microdomain, which in leukocytes functions to regulate activation, motility and antigen presentation. The importance of tetraspanin microdomains in immunity is highlighted by the perturbations in the immune system observed in tetraspanin-deficient mice. 相似文献
46.
Nicolai S.C. van Oers Soo-Jeet Teh Bryan A. Irving Jacqueline Tiong Arthur Weiss Hung-Sia Teh 《Journal of immunological methods》1994,170(2):261-268
The T cell receptor (TCR) comprises an antigen-specific β heterodimer non-covalently associated with the CD3 γδε and TCR ζ subunits. Both the CD3 and TCR ζ subunits are proposed to be responsible for the intracellular signal-transduction events. We report here the production of eight monoclonal antibodies (mAbs) that bind in an ELISA assay to a 113 amino acid synthetic peptide corresponding to the cytoplasmic domain of TCR ζ. Western blot analysis of anti-CD8 precipitates of lysates of transfectants expressing chimeric CD8/ζ constructs encoding increasing COOH-terminal truncations of TCR ζ indicates that four of these mAbs recognized the region of TCR ζ chain comprising the last 29 COOH-terminal residues. Thus, this region of TCR ζ may encode an immunodominant epitope. Furthermore, one of these mAbs, G3, is capable of precipitating both non-phosphorylated and tyrosine phosphorylated TCR ζ. The G3 mAb should be useful for elucidiating the structural and signalling characteristics of the TCR ζ chain. 相似文献
47.
48.
A 2-week efficacy and safety study of eszopiclone in elderly patients with primary insomnia 总被引:6,自引:0,他引:6
STUDY OBJECTIVES: Evaluate the efficacy of eszopiclone in primary insomnia. DESIGN/SETTING: Randomized, double-blind, placebo-controlled multicenter in outpatient setting with weekly visits. PARTICIPANTS: Two-hundred thirty one men and women aged 65 to 85 years (mean age 72.3 years) with primary insomnia, as defined by the Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition. INTERVENTIONS: Eszopiclone 1 mg (n = 72), eszopiclone 2 mg (n = 79), or placebo (n = 80) nightly for 2 weeks. MEASUREMENTS/RESULTS: Efficacy was assessed using an interactive voice response system. Following the predefined hierarchical testing strategy, the eszopiclone 2-mg group had a significantly shorter sleep latency compared with placebo over the double-blind period (P = .0034). The eszopiclone 2-mg group had significantly longer total sleep time (P = .0003) and eszopiclone 1-mg group had significantly shorter sleep latency (P < or = .012) compared with placebo. The eszopiclone 1-mg group was not significantly different from placebo on total sleep time or any other secondary efficacy endpoint. Secondary analyses indicated that the eszopiclone 2-mg group had significantly less wake after sleep onset; significantly fewer and shorter in duration daytime naps; and significantly higher ratings of sleep quality and depth, daytime alertness, and sense of physical well-being compared with placebo (P < .05). Eszopiclone was well tolerated. The most frequent treatment-related adverse event was unpleasant taste. CONCLUSION: Nightly treatment with eszopiclone 1 mg effectively induced sleep, while the 2-mg dose was effective in inducing and maintaining sleep. Eszopiclone was well tolerated in elderly patients with primary insomnia, and the sleep efficacy was accompanied by significantly less napping and significantly higher ratings of daytime alertness, sense of physical well-being, and several quality-of-life parameters at the higher dose. 相似文献
49.
Mouse peritoneal cells (PC) in culture produce auto-antibodies lyzing bromelain-treated mouse erythrocytes (MRBCbr). These auto-antibodies have been obtained in an homogeneous form in substantial amounts after cell fusion of PC with myeloma X63.Ag8. They have been identified as the anti-Hb-auto-antibodies described by us in 1980. Once coupled to fluorescent microspheres (Ms), they were used to detect the corresponding antigen. It was found that the specific antigen was not only present on the surface of all MRBCbr but also, in a much smaller proportion, on some normal MRBC. Its distribution is not restricted to the mouse: pigeon RBC is stained heavily; human red cells give, more or less, positive reaction, according to their blood group. Some species, as horse RBC, are consistently negative. The opportunity offered by the fluorescent microspheres technique to trace the antigen recognized by the Hb-auto-antibody in the mouse tissues and on cells from other species should lead to a better understanding of the cross-antigenicity of many RBC and of the peculiar auto-immune process involving MRBCbr in the mouse. 相似文献
50.
Pérez C Tous M Gallego S Zala N Rabinovich O Garbiero S Martínez MJ Cunha AM Camino S Cámara A Costa SC Larrondo M Francalancia V Landreau F Bartomioli MA 《Journal of medical virology》2004,72(4):661-667
Human herpesvirus-8 (HHV-8) causes Kaposi's sarcoma (KS) and lymphoproliferative disorders in both HIV-infected and uninfected patients. HHV-8 has a worldwide occurrence but infection rates vary according to a combination of geographic and behavioral risks. The main transmission route seems to be sexual, nevertheless, nasal secretions, saliva, blood, and organ graft have been proposed. HHV-8 was postulated as a new infectious agent for screening in blood donors. The aim of this study was to evaluate the prevalence of antibodies against HHV-8 antigens in blood donors of South America. Serum samples from 2,470 blood donors from Argentina, Brazil, and Chile corresponding to five geographic regions were studied by indirect immunofluorescence assay (IFA). Seroprevalence rate was 3.7% (92/2,470; 95% CI 2.9-4.5) in the entire blood donor population distributed as follows: Argentina, 4.0% (Buenos Aires city, 4.3%; Bahia Blanca, 2.4%; and Córdoba, 4.0%), Campinas (Brazil), 2.8%; and Santiago de Chile, 3.0%. There was no difference (P>0.05) between men and women or age related, except in Brazil where positive cases were 30-49-year-old males. The present study, which includes different geographical areas of multiple countries from South America, has not been done before. The results show similar prevalence rates among the studied zones corresponding to low-prevalence regions. South America is a large sub-continent with a wide spectrum of population and geographical characteristics, thus, more HHV-8 prevalence studies should be necessary to establish possible regional differences. 相似文献