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91.
IL Woolf N El Sheikh H Cullens WM Lee AL Eddleston R Williams AJ Zuckerman 《Canadian Metallurgical Quarterly》1976,2(6037):669-671
The possible importance of humoral immunity in the pathogenesis of fulminant hepatitis was investigated by comparing 17 patients with fulminant hepatitis type B with 20 patients with severe but non-fulminant disease. Hepatitis B surface antigen (HBsAg) was cleared from the serum significantly faster (P less than 0-001) in those with fulminant hepatitis, and in 41% anti-HBsAg (HBsAb) was detectable by radioimmunoassay (RIA) at presentation. In all 11 sera from patients with fulminant hepatitis that were examined by electron microscopy aggregates of HBsAg and HBsAb were seen. In contrast, HBsAb was never detected by RIA in those with non-fulminant hepatitis, and in only one serum specimen (5%) were aggregates seen on electron microscopy. A significant sex difference between fulminant and non-fulminant hepatitis was observed, 65% of patients with fulminant hepatitis but only 15% of patients with non-fulminant hepatitis being women (P less than 0-01). An enhanced production of HBsAb in fulminant hepatitis, by leading to free HBsAb in portal blood, may cause an Arthus reaction in the sinusoids of the liver with ensuing ischaemic necrosis of hepatocytes. 相似文献
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A novel approach is suggested for alleviating the curse of dimensionality in discrete dynamic programming as applied to optimal control problems. By using multidimensional B-splines to approximate the overall minimum objective and optimal control function, a significant reduction of computer storage is made. The ease and accuracy of this approach is demonstrated on a two-dimensional control problem. Extensions of this procedure are also proposed that result in increased accuracy. 相似文献
95.
This review on non-heartbeating donation focusses on three issues: the number of kidneys procured from a non-heartbeating donor programme, the transplant results and the influence of a non-heartbeating programme on public opinion regarding transplantation. 相似文献
96.
A method is presented in which Feulgen-stained apoptotic cells are identified among cultured cells in situ using computerized image analysis of their nuclei. Images of either control (untreated) human lymphoblastoid cell nuclei or of similar cells treated with 3mM methyl methanesulfonate for 1 h, which induces apoptosis in 100% of the cells, were converted to a standard size (80 x 80 pixels) and Fourier transforms and boundary images based on 21 proportional mean gray-level thresholds obtained. The perimeter and the mean fractal dimension of the latter and 39 selected coefficients of the former were then obtained from which data were chosen heuristically and subjected to multivariate linear discrimination analysis. Eighty-two percent of a teaching set of 50 nuclei and 69% of a test set of 29 nuclei were correctly identified as apoptotic versus nonapoptotic by the computer, compared with 57% identified correctly by a panel of 7 pathologists. This study shows the feasibility of using this type of analysis to directly identify apoptotic cells in culture, and probably also in tissues, by direct observation using computerized imaging technology. 相似文献
97.
Bong Gu Lee Jun IL Yang Euna Kim Sun Woo Geum Ju-Hyeong Park Min-Kyeong Yeo 《Indoor air》2021,31(5):1553-1562
The advent of high-throughput sequencing methods allowed researchers to fully characterize microbial community in environmental samples, which is crucial to better understand their health effects upon exposures. In our study, we investigated bacterial and fungal community in indoor and outdoor air of nine classrooms in three elementary schools in Seoul, Korea. The extracted bacterial 16S rRNA gene and fungal ITS regions were sequenced, and their taxa were identified. Quantitative polymerase chain reaction for total bacteria DNA was also performed. The bacterial community was richer in outdoor air than classroom air, whereas fungal diversity was similar indoors and outdoors. Bacteria such as Enhydrobacter, Micrococcus, and Staphylococcus that are generally found in human skin, mucous membrane, and intestine were found in great abundance. For fungi, Cladosporium, Clitocybe, and Daedaleopsis were the most abundant genera in classroom air and mostly related to outdoor plants. Bacterial community composition in classroom air was similar among all classrooms but differed from that in outdoor air. However, indoor and outdoor fungal community compositions were similar for the same school but different among schools. Our study indicated the main source of airborne bacteria in classrooms was likely human occupants; however, classroom airborne fungi most likely originated from outdoors. 相似文献
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We report a new form of congenital muscular dystrophy (CMD) in 4 patients from three unrelated families with probable autosomal-recessive inheritance. All patients had the clinical characteristics of merosin-positive congenital muscular dystrophy, but had marked mental retardation. The disease was slowly progressive and 1 patient died from dilated cardiomyopathy at the age of 13 years. In addition to dystrophic changes with necrosis and regeneration in muscle, the most striking finding was mitochondrial depletion in the center of the sarcoplasm. Mitochondria at the periphery of fibers were markedly enlarged ("megaconial" appearance) with complicated cristae, and contained a normal amount of mitochondrial DNA by in situ hybridization. Mitochondrial enlargement may represent functional compensation for mitochondrial depletion in the central sarcoplasm, where myofibrillar degeneration occurred. 相似文献
100.