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81.
Mechanism of suppression of cell-mediated immunity by measles virus   总被引:2,自引:0,他引:2  
The mechanisms underlying the profound suppression of cell-mediated immunity (CMI) accompanying measles are unclear. Interleukin-12 (IL-12), derived principally from monocytes and macrophages, is critical for the generation of CMI. Measles virus (MV) infection of primary human monocytes specifically down-regulated IL-12 production. Cross-linking of CD46, a complement regulatory protein that is the cellular receptor for MV, with antibody or with the complement activation product C3b similarly inhibited monocyte IL-12 production, providing a plausible mechanism for MV-induced immunosuppression. CD46 provides a regulatory link between the complement system and cellular immune responses.  相似文献   
82.
The growth of lead diborate and the viscosity of its melt were determined as a function of temperature. These data were used to examine several theories of the growth of crystals from the melt. The data were in good agreement with the theory of Tornbull and Cohen. At large under coolings the growth rate appeared to be controlled by the rate of diffusion across the crystal-melt interface, whereas at smaller undercoolings the growth rate appeared to be controlled by reaction at the crystal-melt interface.  相似文献   
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Systemic lupus erythematosus with a protein-losing enteropathy   总被引:2,自引:0,他引:2  
Anasarca with pronounced hypoalbuminemia developed in a young woman 15 months after the onset of a mild, arthralgic type of systemic lupus erythematosus (SLE) without evidence of active nephritis. Investigation indicated a gastrointestinal rather than a renal site for protein loss. A full clinical remission was achieved with low-dose corticosteroid therapy.  相似文献   
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Ethanol suppressed, in a dose-related manner, glucose-induced insulin (IRI) release and thus delayed the disappearance of glucose from the blood of rats. Pretreatment with pyrazole, an alcohol dehydrogenase inhibitor, exacerbated the effect of ethanol on IRI release, glucose tolerance and glucagon (IRG) release. These results suggest that ethanol produces glucose intolerance by inhibiting glucose-induced IRI release and by augmenting IRG release. Moreover, these findings indicate that ethanol does not have to be metabolized completely in order to produce these effects.  相似文献   
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Sodium beta-alumina solid electrolytes were prepared containing up to 7.5 wt% SiO2 and their density, soda content, micro-structure, and ionic resistivity were studied. The resulting microstructures have glassy sodium ahminosilicate phases inhomogeneously distributed. The glassy phase collects preferentially at triple grain junctions, but occasionally penetrates along some grain boundaries as a thin layer (10 to 20 Å). Alpha-alumina is also present, especially with high silica content and when the samples are not protected with β-alumina powder during sintering. The total specific ionic resistivity follows a dependence on silicate content typical of 2-phase mixtures.  相似文献   
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