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91.
We reported a female presented with an initial diagnosis of metastatic axillary lymph‐node carcinoma that comprehensive assessments revealed a definitive diagnosis of high‐grade serous ovarian carcinoma as the primary tumor.  相似文献   
92.
In this study, compacted hematite (Fe2O3) preforms were made and sintered at various temperatures, such as 1250 °C and 1300 °C, using both conventional and microwave sintering methods. The density, porosity, microhardness, cold crushing strength, microphotographs, and X-ray diffraction (XRD) analysis of the sintered preforms were used to evaluate the performance of the two sintering methods. It was found that microwave sintered preforms possessed lesser porosity and higher density than conventionally sintered preforms owing to uniform heating of the powdered ore in microwave sintering method. Furthermore, it was also observed that microwave sintered preforms exhibited relatively higher cold crushing strength and hardness than conventionally sintered preforms. Thus, the overall results revealed that microwave sintering yielded better properties considered in the present study.  相似文献   
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Effects of Escherichia coli and Staphylococcus aureus on cartilage and chondrocytes in culture are reported. Under these conditions, bacterial effects on cartilage degradation and cell viability are measured in the absence of inflammation. E coli causes a 28% loss and S aureus an 83% loss of cartilage glycosaminoglycan within 48 hours. Collagen content is unchanged. Both bacterial species induce chondrocyte death in explants and in monolayers within 48 hours. Bacterial effects on glycosaminoglycans and cell viability do not result from depletion of nutrients from the culture medium. Serum in the culture media inhibits the bacterial effects on cartilage degradation but does not prevent cell death.  相似文献   
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Thirty-seven patients with criteria for systemic lupus erythematosus (SLE) and 18 normal controls were studied for their spontaneous background IgM antibody plaque-forming cell number to specific chemical haptens. Active SLE patients had significantly more plaque-forming cells in their peripheral blood to a total of five chemical determinants than did patients with inactive disease or controls. This increased number of plaque forming-cells correlated with depressed serum C3 levels by Spearman rank-order analysis. The finding of elevated numbers of spontaneous IgM plaque-forming cells to defined chemical haptens supports the concept that active SLE demonstrates a generalized increase in B-cell activity toward a variety of antigens.  相似文献   
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Brain endothelial ultrastructural properties contribute to maintain proper blood-brain barrier (BBB) function. Several physiological and pathological conditions have been shown to alter BBB permeability to blood-borne molecules, acute and chronic stress among them. In the rat, early life stress increased transvascular transport of Evans blue, however, the route of tracer extravasation is not fully known; therefore the aim of the present experiment was to describe the ultrastructural changes in endothelial cells subsequent to chronic perinatal stress in order to ascertain the route for transvascular transport of an electrodense tracer. Pregnant Wistar rats and their litters were used. Four pregnant rats were subjected to forced swimming between gestational days 10 to 20. After delivery, half of the control litters underwent 180 min maternal separation from postnatal day 2 to 20. Controls were kept free of any stress manipulation. At sacrifice between postnatal days 1 to 30 subjects were given intracardially the lectin wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). WGA-HRP stained hippocampi were processed for ultrastructural analysis, transmission electron micrographs were obtained and endothelial ultrastructural parameters quantified using the ImageJ software. Both stress procedures accelerated gross microvessel development by decreasing capillary wall thickness and endothelial microvilli. However, early-life stress also neutralized endothelial glycocalyx, increased vesicle-mediated transport and tended to promote the formation of secondary lysosomes containing endocytosed WGA-HRP vesicles, all parameters of altered endothelial cell function. Tight junction development in both stress groups was similar to the control pups.  相似文献   
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