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D B Hrdy N A Barnicot C A Alper 《Folia primatologica; international journal of primatology》1975,24(2-3):173-187
26 specimens of Presbytis entellus were examined for a variety of blood proteins. In contrast to previous studies of other species of leaf monkeys, our P.entellus sample proved to be very heterogeneous. Polymorphisms were found in the third component of complement, group-specific component, glycine-rich beta-glycoprotein, alpha1-antitrypsin, phosphoglucomutase, 6-phosphogluconate dehydrogenase, adenylate kinase, superoxide dismutase, malate dehydrogenase, and phosphohexose isomerase. Variable band strengths that might represent polymorphism were found in acid phosphatase and lactate dehydrogenase. Further analyses of the P. cristatus sample studied by Barnicot and Hewett-Emmett failed to disclose variation. The interpretation of blood protein variability in relation to sample collection and population structure is discussed. 相似文献
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Positive selection of mutants with deletions of the gal-chl region of the Salmonella chromosome as a screening procedure for mutagens that cause deletions. 总被引:28,自引:13,他引:15 下载免费PDF全文
We have developed a convenient and specific positive selection for long deletions through the gal region of the chromosomes of Salmonella typhimurium and Escherichia coli. Through simultaneous selection for mutations in the two closely linked genes, gal and chlA, a variety of deletions of varying length, some extending through as much as 1 min of the chromosome, could be readily obtained. Many of these deletions resulted in the loss of a gene, which we named dhb, concerned with the ability of the bacterium to synthesize the iron chelating agent enterobactin. The selection was adapted for the screening of mutagens for their ability to generate long deletions in the bacterial deoxyribonucleic acid. Forty agents were screened for this capability. Nitrous acid, previously reported to be an efficient mutagen for this purpose, increased the frequency of deletion mutations 50-fold in our system. Three others, nitrogen mustard, mitomycin C, and fast neutrons, were shown to increase the frequency of long deletions between five- and eightfold. The remainder were found to be incapable of generating these deletions. 相似文献
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D Raum Z Awdeh J Anderson L Strong J Granados L Teran E Giblett E J Yunis C A Alper 《American journal of human genetics》1984,36(1):72-79
In the course of study of families for the sixth chromosome markers HLA-A, C, B, D/DR, BF, and C2, the two loci for C4, C4A, and C4B, and glyoxalase I, we encountered five examples of probable duplication of one or the other of the two loci for C4. In one of these, both parents and one sib expressed two different structural genes for C4B, one sib expressed one, and one sib expressed none, suggesting that two C4B alleles were carried on a single haplotype: HLA-A2, B7, DR3, BFS1, C2C, C4A2, C4B1, C4B2, GLO1. In a second case, two siblings inherited C4B*1 and C4B*2 from one parent and C4B*Q0 from the other. This duplication appeared on the chromosome as HLA-AW33, B14, DR1, BFS, C2C, C4A2, C4B1, C4B2, GLO2. In a third, very large family with 3 generations, a duplication of the C4B locus occurred which was followed in 2 generations. In one individual, there were three C4B alleles and two C4A alleles. One of the C4B alleles had a hemolytically active product with electrophoretic mobility near C4B2 and was designated C4B*22. It segregated with C4B1 in the family studied. The complete haplotype was HLA-A11, CW1, BW56, DR5, BFS, C2C, C4A3, C4B22, C4B1, GLO2. In another family with 12 siblings, one parent and eight children expressed two C4A alleles on the haplotype HLA-AW30, BW38, DR1, BFF, C2C, C4A3, C4A2, C4BQ0, GLO1.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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