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91.
D. A. Lewis 《The Biochemical journal》1969,115(3):489-493
1. After the administration of large doses of androsterone, epiandrosterone, dehydroepiandrosterone and testosterone to mice, females excreted more of the dose conjugated with sulphuric acid than did males. 2. Liver slices from female mice conjugated androgens with sulphuric acid to a greater extent than did slices from males. 3. Sulphotransferase preparations from livers of female rats and mice catalysed the formation of dehydroepiandrosterone sulphate at a faster rate than preparations from livers of the male animals. 4. A possible explanation for the observed sex differences is discussed. 相似文献
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D. A. Lewis 《The Biochemical journal》1968,106(2):497-501
1. After large doses of androsterone, epiandrosterone, dehydroepiandrosterone and testosterone, female rats excreted more of the dose conjugated with sulphuric acid than did the males. 2. Androgens were also incubated with liver slices from male and female rats. Slices from females conjugated androgens with sulphuric acid to a greater extent than did slices from males. 3. The amount of unchanged androgen present in the faeces of orally dosed animals was 4-35% of the dose. 相似文献
94.
Inhibitory Effects of Dichlorophenoxyacetones on Auxin-induced Growth of Avena Coleoptile Sections 下载免费PDF全文
Six dichlorophenoxyacetones were synthesized and examined as potential metabolic antagonists utilizing Avena coleoptile sections and the straight growth assay procedure. Supplements of indoleacetic acid promoted growth of the sections which were inhibited by the analogs; the most inhibitory derivatives were 2,3-; 2,4-; 2,5-; and 3,4-dichlorophenoxyacetone which produced half-maximal growth responses (relative to the unaug-mented control growth) at concentrations of 106, 86, 80, and 62 μg/ml, respectively. A Lineweaver-Burk plot of the data for the inhibition by 2,4-dichlorophenoxyacetone and its reversal by indoleacetic acid appeared to represent an uncompetitive-like inhibition. 相似文献
95.
Food specimens (490) in nine categories were examined for total aerobic plate count and numbers and types of coliform organisms, including the enteropathogenic Escherichia coli (EEC). The total counts were compared with various suggested standards, and a limit of 100,000/g appeared to be a realistic goal, except for certain food types with a high level of natural flora. Plate counts in VRB were compared to counts obtained by isolation by enrichment in LST Broth, and the latter method produced a higher percentage of isolations. The presence of E. coli was determined by use of EC Medium incubated at 44.5 +/- 0.1 C. Only 40.4% of the positive EC tubes, however, contained E. coli. It appeared that a limit of 10 coliform organisms per g as a suggested standard could be met with several types of foods. Isolation of EEC was obtained only three times, or in 0.6% of the specimens. 相似文献
96.
Walter H. Lewis 《The Botanical review》1967,33(2):105-115
Low fertility and vigor, and requirements of ecological niches distinct from diploids are not universal characteristics of autoploids. InClaytonia, Hedyotis, Oldenlandia, and other genera, occurrence and frequency of both polyploids and aneuploids within species populations suggest a greater role of such mutations in the evolution of vascular plants than heretofore presumed. 相似文献
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