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151.
As spontaneous abortion is a frequent finding in females with Factor XIII (FXIII) deficiency it has been presumed that this clotting factor is essential to normal pregnancy. FXIII subunit a (FXIII A) has been demonstrated in the homogenate of human uterus, but no information on its cellular distribution has been published, so far. In the present study first FXIII A was detected in paraformaldehyde-fixed, paraffin-embedded sections of human uterus by immunoperoxidase technique. Cells containing FXIII A were localized between collagen fibrils stained by Picrosirius Red F3B in the connective tissue. To characterize them the immunofluorescent detection of FXIII A was combined by the visualization of different marker antigens of monocytes and macrophages recognized by Leu-M3, RFD7, anti-HLA-DR and DAKO-anti-macrophage monoclonal antibodies on frozen sections. The coexpression of FXIII A with monocyte and macrophage differentiation marker antigens clearly proves that cells containing FXIII A in the uterus are monocyte-derived tissue macrophages. The results well agree with our previous findings demonstrating FXIII A in human monocytes and different types of macrophages. On the basis of these results, the presence of FXIII A does not seem to be a specificity of the uterus but a characteristic of monocyte/macrophage cell line including tissue macrophages, in general. 相似文献
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The formation of two extracellular enzymes (α-amylase and a proteinase) ofB. subtilis was investigated in batch and continuous cultures. Differences were observed in the production of both enzymes in batch culture when studied in flasks and in a fermentor. The values of proteinase activity from continuous cultivation never reached those obtained during batch cultivation. The optimal dilution rate for proteinase synthesis was 0.1 – 0.2/h. The optimal dilution rate for the production of α-amylase was 0.2 –0.3/h. 相似文献
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By testing serial serum samples of 213 pregnant women for rubellavirus, of 196 for herpes simplex virus and of 134 for Toxoplasma gondii, it was found that during pregnancy there was a fall in the humoral antibody level. Presence and titre of antibodies were lower in sera of pregnant than of non-pregnant women. Alteration of the humoral antibody level during pregnancy may influence serological studies aimed at clarifying the role of infections in fetal malformations. Serial serum samples (4 samples from each pregnant woman involved) should be tested for obtaining reliable data regarding the frequency of infections during pregnancy. 相似文献
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