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51.
Summary Red blood cell esterase D (ESD) polymorphism was studied in a French-Canadian population from Quebec city, Canada, by means of high voltage electrophoresis on agarose gel followed, in heterozygotes for ESD1, by IEF to reveal the possible allele ESD*5. Frequencies of the ESD alleles in 904 unrelated individuals were ESD*1: 0.888, EDS*2: 0.095 and ESD*5: 0.017. The segregation pattern observed in 275 families confirmed a Mendelian inheritance of three autosomal alleles. 相似文献
52.
C-Glycosylation of 5,7-dihydroxy-3′,4′,5′-trimethoxyflavone was carried out with acetobromo-α-d-glucose, -α-d-galactose, -α-d-xylose, -β-l-arabinose and -αt-L-rhamnose. The respective 6-C-glycosides and 6, 8-di-C-glycosides (excepted for galactose) were isolated and permethylated. MS and TLC comparison confirmed the proposed structures of five natural tricetin-derived C-glycosides. 相似文献
53.
Claude Lefevre 《Bulletin of mathematical biology》1983,45(1):11-20
This paper is concerned with a generalization of the simple epidemic model in which the infective population is partitioned
intom classes, each of specific infectiousness. Attention is restricted, however, to the case where all the meeting rates between
two individuals are equal to each other. Both deterministic and stochastic versions are examined. In either case the development
in time of the epidemic process is investigated by exploiting a connection with the standard simple epidemic model. Finally,
it is shown that the technique used also applies to a similar model for the spread of information. 相似文献
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Michel GuerineauClaude Grandchamp Claude PaolettiPiotr Slonimski 《Biochemical and biophysical research communications》1971
This paper describes the isolation of a pure population of covalently closed circular twisted DNA molecules from yeast. These molecules are homogeneous in size, that is consist of monomers of 2.2μ and of multiple length oligomers of n x 2.2μ. While no data rule out the mitochondrial origin of this DNA, its actual intracellular localization remains unknown; it displays the same buoyant density as the main nuclear DNA and therefore is not the heavy nuclear satellite DNA (γ-DNA described by Moustacchi and Williamson (1966)); although circular molecules represent only 1 to 5 % of the total DNA, they can be prepared in sizable and reproducible amounts by a method based on the use of mechanical disruption of yeast cells rather than lysis by snail gut juice. 相似文献
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Agar Plate Method for Detecting Microorganisms Which Produce Equilin and Other Estrogens from Various Steroids 总被引:1,自引:1,他引:0 下载免费PDF全文
The intense red color produced by a reagent specific for xi(7)-estrogens is used to directly detect microorganisms which produce these estrogens from various steroids. 相似文献
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A mass in the neck, facial pain and cranial nerve palsies are the most common presenting symptoms of malignant tumours of the nasopharynx. Surgery is limited to biopsy for histological diagnosis. External irradiation is the treatment of choice, both for the primary lesion and the regional and distant metastases. Illustrative case histories are presented in detail. Experience over a 20-year period demonstrates that a 20% five-year survival rate has been obtained. 相似文献