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Both anti-CD40 antibodies and anti-immunoglobulin (Ig) coupled to Sepharose induced proliferation of resting B cells and suppressed lipopolysaccharide (LPS)-induced B-cell differentiation to immunoglobulin secretion at comparable levels determined with the plaque-forming assay and Ig RNA steady state levels. Anti-CD40 antibodies also increased the proliferation of B cells stimulated by T helper cells in vitro while suppressing their differentiation to Ig secretion. Further, B cells preactivated by anti-Ig, anti-CD40 or a combination of the two mitogens could be restimulated by anti-CD40 but not by anti-Ig antibodies. Phenotypic divergence of Ig and CD40 signals regarding surface expression of activation markers was observed. Restimulation of anti-Ig- or anti-CD40-prestimulated cells with anti-Ig induced apoptosis whereas apoptosis could be inhibited when cells were recultivated with anti-CD40. 相似文献
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MF Hovell S Russos MK Beckhelm JA Jones SM Burkham-Kreitner DJ Slymen CR Hofstetter B Rubin 《Canadian Metallurgical Quarterly》1995,11(5):288-293
A sample of private orthodontic practices (n = 40) from a controlled trial for clinician-initiated tobacco-use prevention was used to test the effectiveness of preventive medicine representative (PMR) visits in creating and maintaining an anti-tobacco office environment. Clinical staff of 20 offices, randomly assigned to the experimental group, were trained by a PMR on the use of anti-tobacco materials (no-smoking signs, posters, and print materials). Twenty control-group offices did not receive any training or special treatment. Subsequently, experimental-group offices were visited by a PMR once every three months and were telephoned six weeks after each visit over a 12-month period. During visits and phone calls, PMRs prompted offices to order anti-tobacco materials. Visits served to introduce offices to new materials and to encourage their continued use. Data from direct observations and self-report measures showed significant differences between experimental and control offices for display of anti-tobacco materials at 1.5 months and 12 months (P < .001). Results suggest that PMR visits may serve as an effective method of introducing and maintaining preventive medicine procedures in clinical environments. 相似文献
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BR Babu SJ Zhu AV Ramayya JH Hamilton LK Peker MG Wang TN Ginter J Kormicki WC Ma JD Cole R Aryaeinejad K Butler-Moore YX Dardenne MW Drigert GM Ter-Akopian YT Oganessian JO Rasmussen S Asztalos IY Lee AO Macchiavelli SY Chu KE Gregorich MF Mohar S Prussin MA Stoyer RW Lougheed KJ Moody JF Wild 《Canadian Metallurgical Quarterly》1996,54(2):568-571
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Pulmonary superoxide dismutase (SOD) plays an important role in the lung defense against O2 toxicity. We have previously demonstrated that tracheal insufflation of interleukin-1 alpha (IL-1) selectively enhances pulmonary MnSOD and protects rats against O2 toxicity. However, little is known about the cellular distribution of pulmonary MnSOD- and CuZnSOD-specific proteins. We performed immunohistochemistry in plastic sections (2 microns thick) to determine the effects of hyperoxia and IL-1 on the cellular distribution of pulmonary MnSOD and CuZnSOD in rats. MnSOD and CuZnSOD were present in all lung cells. Smooth muscle and endothelial cells appeared to contain higher immunoreactive MnSOD and CuZnSOD proteins than other lung cell types. Exposure of rats to 100% O2 for 24 hr had no effect on the cellular distribution and intensity of pulmonary MnSOD. However, at 50 hr after O2 exposure the intensity of pulmonary MnSOD was reduced. In contrast, tracheal insufflation of IL-1 markedly enhanced the intensity of pulmonary MnSOD in rats exposed to O2 for 50 hr. Neither O2 exposure nor IL-1 insufflation had any apparent effect on the distribution and intensity of pulmonary CuZnSOD. We conclude that IL-1 selectively enhances pulmonary MnSOD and that this effect is manifested in most lung cells, particularly smooth muscle and endothelial cells. 相似文献
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Vaginal colonization of mothers with Group B beta-hemolytic streptococcus (GBS) has been recognized as a risk factor for neonatal morbidity. The relationship of GBS colonization to risks for the mother who undergoes cesarean section has not been defined. In this study, we found that, among patients who underwent cesarean section, the 19% of them who were colonized with GBS had a higher incidence of standard fever (66.6% vs. 30.5%), clinical diagnosis of endomyometritis (61.1% vs. 12.5%), and use of antibiotics (61.1% vs. 26.3%) in relationship to a significantly increased frequency of premature rupture of the membranes (50.0% vs. 14.8%). Reasons for the association between vaginal colonization and increased morbidity are discussed. 相似文献
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