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991.
The cytoplasmic ribosomal proteins of Microsporum canis were characterised in basic-acidic and basic-SDS two-dimensional polyacrylamide gel electrophoresis systems. The small subunit contained 28 proteins and the large subunit 38 proteins. The molecular weights of these proteins were in the range of 32,500 to 7600 and 48,000 to 11,000 in the small and large subunits, respectively. The 80S ribosomes showed 65 and 66 protein spots in basic-acidic and basic-SDS gel systems, respectively. 相似文献
992.
993.
In this paper we investigate a simple method of modifying well known nonparametric tests for the several samples location problem to yield a class of test statistics suitable for ordered alternatives. Optimum member of the class is identified in each case and its efficacy obtained. The method is applied to five statistics. 相似文献
994.
995.
996.
The essential oil from flowers and leaves of Adenocalymma alliaceae (Bignoniaceae) consists almost entirely of diallyl di-, tri-and tetra-sulphide, a mixture formerly encountered within the Allium genus but never before convincingly recognized within the class of dicotyledonous angiosperms. 相似文献
997.
998.
P N Rao 《Steroids》1971,18(2):219-229
The preparation of 9alpha, 11xi-tritiated 17alpha-ethinyl estradiol, mestranol, estradiol-17beta, and norethindrone are described. Estrone-3-methyl ether was employed as starting material, and ethinylation with lithium acetylide-ethylene diamine resulted in 95% mestranol. Demethylation of mestranol with boron tribromide at 0 degrees resulted in 92% 17alpha-ethinyl estradiol. Dimethylsulfoxide was the choice of reagent for the condensation reaction which was complete at room temperature in about 4 hours. The usually less than 3% of unreacted 17-oxo product was removed by Girard separation. Demethylation of methyl ether with boran tribromide in methylene chloride resulted in an excellent yield of 17alpha-ethinyl estradiol-9alpha, 11xi-tritium. 3-methoxyestra-1,3,5-trien-17-one-9alpha, 11xi-tritium was reduced with sodium bis(2-methoxyethoxy) aluminum hydride to the 17beta-hydroxy compound and subsequent demethylation resulted in estradiol-9alpha, 11xi-tritium. The general method of Ringold et al was employed for the preparation of 17beta-hydroxy-17alpha-ethinylestr-4-en-3-one. Improvements for small scale radiosynthesis are also presented. 相似文献
999.
Sixty-two strains of yeasts, molds and bacteria were screened for lactase (β-D-galactosidase) activity. Strains exhibiting
the enzyme activity were evaluated for cell yield as well as enzyme units available per litre of the medium, per g cell dry
weight and per mg protein of their cell-free extracts. The molds exhibited lowest enzyme activity but highest cell yields,
bacteria produced lowest cell yield and maximum enzyme activity. Cultures exhibiting very high activity among yeasts wereSaccharomyces fragilis (strain 3217) and among bacteriaStreptococcus cremoris (strain H),Lactobacillus bulgaricus (strain RTS and 1373) andLeuconostoc citrovorum (strain 8081). 相似文献
1000.
Drechslera boeremae sp. nov. is described from India, having been isolated from the leaf-spot lesions of Portulaca oleracea L., a commonly grown vegetable.Contribution No. 555 from the Department of Mycology and Plant Pathology. 相似文献