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Benzene, an accepted leukemogen, has been suggested to cause other hemato- and lymphopoietic cancers. Here we review the published literature for non-Hodgkin lymphoma (NHL) and occupational exposure to benzene. Six cohorts, sixteen case–control studies and two studies of other designs were identified through keyword searches of bibliographic databases. Twenty-two of twenty-four studies found no association between NHL and ever exposed to benzene compared to never; a random-effects meta-analysis gave a pooled risk estimate of 1.11 (95% confidence interval 0.94–1.30). Our finding of no effect agrees with one of two previous meta-analyses. The other meta-analysis examined if high benzene exposure increased NHL risk but a lack of consistent exposure categories within the same metric should have precluded pooling risks by exposure level. Instead, we reviewed whether dose–response relationships existed. The best available data came from six studies where exposure was estimated from historical measurements and on the whole, no trends in risks of NHL with rising cumulative, average, peak, or duration of benzene exposure were found. NHL is a heterogeneous group of malignancies and although less well-studied, benzene was not associated with any NHL subtype. In conclusion, benzene at either low or high doses does not increase the risk of NHL.  相似文献   
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Ovarian cancer G protein-coupled receptor 1 (OGR1) is a proton-sensing molecule that can detect decreases in extracellular pH that occur during inflammation. Although OGR1 has been shown to have pro-inflammatory functions in various diseases, its role in autoimmunity has not been examined. We therefore sought to determine whether OGR1 has a role in the development of T cell autoimmunity by contrasting the development of experimental autoimmune encephalomyelitis between wild type and OGR1-knockout mice. OGR1-knockout mice showed a drastically attenuated clinical course of disease that was associated with a profound reduction in the expansion of myelin oligodendrocyte glycoprotein 35-55-reactive T helper 1 (Th1) and Th17 cells in the periphery and a reduced accumulation of Th1 and Th17 effectors in the central nervous system. We determined that these impaired T cell responses in OGR1-knockout mice associated with a reduced frequency and number of dendritic cells in draining lymph nodes during EAE and a higher production of nitric oxide by macrophages. Our studies suggest that OGR1 plays a key role in regulating T cell responses during autoimmunity.  相似文献   
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Direct measurements of cell number using computer-aided video microscopy   总被引:1,自引:0,他引:1  
Quantitative studies in cell culture require accurate measurements of cell density and kinetics. We have developed a direct, rapid, and noninvasive method for measuring cell number in monolayer culture. Using computer-aided video microscopy, cell number was measured without detaching or chemically destroying the cells, thereby allowing sequential measurements in the same cell population. Cell number measured by computer-aided microscopy closely correlated with hemocytometer counts and determinations of total cell protein. For high-density monolayers of mesenchymal cells, however, staining was required for accurate counts. Unlike other techniques for measuring cell density, computer-aided microscopy was especially accurate in medium- to low-density cultures (less than 6000 cells/cm2). In addition, we applied this technique to the construction of separate proliferation curves for glomerular mesangial and vascular endothelial cells in coculture. These measurements by cell type in coculture are impossible using conventional methods for determining cell number.  相似文献   
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