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排序方式: 共有997条查询结果,搜索用时 453 毫秒
991.
992.
PG Spieckermann MM Gebhard GG G?ring H Kahles VA Mezger CJ Preusse M Stellwaag 《Canadian Metallurgical Quarterly》1980,75(1):97-104
The functional behaviour of membrane systems of the cardiac cell during oxygen deficiency was analyzed and the alterations were related to the metabolic state of the tissue as an index of injury. 1. The retention function of the cell membrane for proteins. With increasing energy deficiency the cardiac sarcolemma loses its ability to retain macromolecules (myoglobin, enzymes) within the cell. Close correlations exist between protein release and oxygen supply as well as ATP content of the tissue. 2. Function of isolated mitochondria after ischemia. In parallel with a strong impairment of oxidative phosphorylation (decrease of QO2, RCI values, phosphorylation rates) the Ca++-transporting activity of mitochondria is continuously depressed with decreasing myocardial ATP. 3. Function of isolated sarcoplasmic reticulum after ischemia. With breakdown of high energy phosphates during ischemia rate and extent of Ca++ binding with decrease markedly. 相似文献
993.
Ectodermal explants from gastrulae of Triturus alpestris were exposed to tritiated cytochalasin B (5 and 10 mug/ml) for 1/2-2 1/2 h. The flat explants failed to heal into compact spheres and the component cells gradually rounded up. Radioactivity in the fixed and sectioned material was analysed by light and electron microscopic autoradiography. Silver grains were found predominantly over the yolk platelets, but were also scattered over other cellular components. Areas containing pigment granules or the feltwork material, present in the apices of dissociating cells of the superficial layer, exhibited higher activity than areas containing mitochondria or cytoplasmic matrix. Lipid droplets and nuclei showed comparatively little activity. The results are discussed in relation to previous findings on the uptake of tritiated cytochalasin D by cell fractions. 相似文献
994.
995.
GG Lloyd 《Canadian Metallurgical Quarterly》1977,18(4):352, 355-352, 358
996.
GG Skellern BI Knight M Otter CK Low WD Alexander 《Canadian Metallurgical Quarterly》1980,9(2):145-147
1 A high performance liquid chromatographic (HPLC) method was used to study the pharmacokinetics of methimazole after oral administration of carbimazole to women in various stages of pregnancy. 2 In one patient it was possible to conduct the study in the first and third timesters: there was an appreciable increase in the apparent clearance of methimazole. 3 Based on the assumption of complete absorption and hydrolysis of carbimazole to methimazole the mean apparent clearance was found to be significantly higher in pregnant patients receiving 10 mg carbimazole than in non-pregnant patients receiving the same dose. 相似文献
997.
HIV infection and AIDS create a unique dilemma for women in their potential for vertical transmission of these conditions. Selected feminist perspectives in ontology, epistemology, and axiology are reviewed to illuminate possible social, cultural, and political circumstances of these women. Drawing both on these perspectives and various sources of data about women with HIV/AIDS, some implications for nursing complete this discussion. 相似文献