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991.
To define mechanisms involved in the transport of immunoglobulins into intestinal fluids, we localized IgM, IgA, IgG, and secretory component (SC) in human intestinal mucosa by the peroxidase-labeled antibody technique. At the light microscopic level, immunocytes containing IgA, IgM, or IgG were found in the lamina propria. IgA, IgM, and SC were prominent in the epithelium of gland crypts; IgG was limited to a few cells at tips of villi. At the electron-microscopic level, SC was localized to perinuclear spaces, endoplasmic reticulum, saccules associated with Golgi complexes, cytoplasmic vesicles, and lateral and basal plasma membranes of columnar epithelial cells. IgA and IgM, but not IgG, also were localized to plasma membranes and cytoplasmic vesicles of these cells. Neither the immunoglobulins nor SC was found within other types of epithelial cells (Paneth, goblet, endocrine). The findings provide evidence that (1) the site of SC synthesis in intestinal epithelium is secretory columnar cells, principally those in gland crypts; (2) the polymeric immunoglobulins IgM and IgA are translocated through such SC-containing cells by a process that involves formation of cytoplasmic vesicles; (3) IgM and IgA could combine with SC during transcellular transport (likely sites are lateral or basal plasma membranes or supranuclear cytoplasm); (4) the monomeric immunoglobulin IgG does not share the transepithelial cell route involved in IgM and IgA transport. 相似文献
992.
Xiaodong Wang Baoqing Li Zhiwei Liu H.T. Roman O.L. Russo K.K. Chin K.R. Farmer 《Power Delivery, IEEE Transactions on》2006,21(3):1063-1067
/sup T/he development of time-frequency and time-scale transforms has progressed rapidly over the last 20 years. The development and progression of numerical acquisition enable the utilization of these mathematical tools to analyze partial discharge in electrical equipment. This paper introduces a new transform, a Hilbert-Huang Transform to analyze partial discharge data. The mathematical model of a Hilbert-Huang Transform is described; and its application in a PD application shows its great advantage. 相似文献
993.
994.
Central nervous system aspergillosis in two young adults 总被引:1,自引:0,他引:1
Unusual and unique features were present in the cases of two patients with central nervous system aspergillosis: One had a previously unreported complication of aspergillosis, extracranial internal carotid artery thrombosis documented by angiography, and in the other patient, cerebral granulomas developed from Aspergillus fumigatus in association with intravenous narcotic abuse. The latter etiologic mechanism was suggested once before. Neither of these patients showed other underlying disease. A detailed neuropathologic examination correlated the salient clinical findings with formation of aspergillosis cerebral granulomata, basilar meningitis, and arterial occlusion. Diagnostic and therapeutic methods in this disease are limited. 相似文献
995.
Seventy-five patients underwent a 90 percent distal gastric bypass for morbid obesity. The average weight was 121.4 kilogram, height 164 centimeters, and age 31.4 years in these 70 women and five men. There was a total of 20 surgical complications in the 75 patients, with wound infection being the most common. Sixteen chronic complications were noted and consisted of vomiting, diarrhea, reflux esophagitis, dysphagia, and vitamin deficiencies. None of the above complications were life-threatening or required dismantling of the bypass. Of 54 patients followed for 12 months or more after gastric bypass, there was a 24.5 percent average weight decrease at 6 months, and this progressed to 35.8 percent by 12 months. Fifty-two patients undergoing small bowel bypass previously at the same institution had a 25.4 percent weight reduction at 12 months. Of 54 patients, 83 percent followed for one or more years after gastric bypass have had an excellent or good clinical result, whereas only 42 percent of the 52 patients undergoing small bowel bypass have had an excellent or good clinical result with the same criteria. It is concluded that the Mason 90 percent distal gastric bypass is a suitable form of surgical treatment for the morbidity obese patient who cannot lose weight by dietary measures. 相似文献
996.
997.
Plasma prostaglandin F (PGF) was measured by a radioimmunoassay method in 24 subjects with tumours of the female genital tract. Levels in the tumour group ranged from 25 pg/ml to 134 pg/ml and were almost all greater than the values observed in a control group of 41 healthy women who had a mean (+/-SD) level of 21 (+/-3.4)pg/ml. There was a relationship between plasma PGF levels and the stage of the disease. Patients with resectable tumours showed a fall in PGF levels postoperatively and those with disseminated malignancy demonstrated increasing levels as the disease progressed. Plasma PGF may provide a clinical prognostic marker in the management of patients with malignant tumours. 相似文献
998.
999.
1000.
Energy analysis is used to determine the low energy crystal structure for polytetrafluoroethylene molecules in the and conformations. The structure for the conformation contains an ordered repeating pattern of a left- and right-handed pair of molecules in a unit cell having projected parameters, a′, b′, and γ′, of 9.60 Å, 5.62 Å, and 91.4 degrees, respectively. These results, the relative orientations of the molecules, and the relative translations of the molecules are in good agreement with results obtained in a concurrent and independent analysis of diffraction data. Energies calculated for rotational and translational displacements in various modes suggest that a range of structures and a fairly large amount of disorder may be present, also in agreement with experiment. 相似文献