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排序方式: 共有609条查询结果,搜索用时 15 毫秒
601.
Previously described glycerol methods for estimation of serum triglyceride were modified. Conditions during saponification and colour development were altered so as to minimize the possibility of glycerol loss. Using this modification, serum triglyceride was determined in 100 healthy men and women, aged 15 to 79 years. There was a log normal distribution. In both sexes the level increased up to the sixth decade and then decreased. In each decade men had higher levels than women. The geometric mean (and 95% limits) for men was 129 mg. % (68-248); for women, 105 mg. % (54-206); and for the entire group, 117 mg. % (59-233). Comparison of results from several laboratories using different methods showed wide variation in serum triglyceride levels. 相似文献
602.
The molecular organization of the beta-globin complex of the deer mouse, Peromyscus maniculatus 总被引:1,自引:0,他引:1
Padgett RW; Loeb DD; Snyder LR; Edgell MH; Hutchison CA d 《Molecular biology and evolution》1987,4(1):30-45
Recombinant DNA clones have been isolated that contain 80 kb of the
beta-globin complex from the deer mouse, Peromyscus maniculatus.
Comparisons of this complex with that from the laboratory mouse, Mus
domesticus (with an order 5'-Hbby, Hbb-bhO, Hbb-bhl, Hbb-bh2, Hbb-bh3,
Hbb-bl, Hbb-b2 3') highlight organizational trends in the beta-globin
complex since the two species diverged. Unlike other mammals studied thus
far, the deer mouse possesses three adult genes. Partial sequence analysis
indicates that each of the three adult genes is intact and hence may be
functional. Hybridization of one of the two Mus pseudogenes, Hbb-bh3, to
genomic blots from Peromyscus reveals that it has a homologous counterpart
in Peromyscus. Homologous genes to the two gamma-like Mus genes, Hbb-bhO
and Hbb-bhl, are also found in Peromyscus. The strong hybridization between
the Hbb-bhl genes and significant nucleotide similarity between the Hbb-bhO
genes suggest that both pairs are important for the ontogeny of these mice
although no known product has been identified for the Hbb-bhO genes. The
presence of Hbb-bhO and Hbb-bhl in Peromyscus suggests that the duplication
that created this related gene set occurred before the two lineages
diverged. A single gene for Hbb-y has been isolated from Peromyscus. The
adult region in Peromyscus has undergone significant divergence from the
same region in Mus, having three rather than two adult genes, the
acquisition of at least 15 kb of extra DNA relative to Mus, and possibly
the loss of the Hbb-bh2 pseudogene. The nonadult region of the complex, in
contrast, contains the same set of genes apparently distributed over the
same amount of DNA as in the Mus beta- globin complex. This observation
suggests that the embryonic region of the complex is more evolutionarily
stable than the adult region.
相似文献
603.
R J Cole J W Kirksey H G Cutler D M Wilson G Morgan-Jones 《Canadian journal of microbiology》1976,22(5):741-744
Two new isomeric metabolites, toxins A and B, were isolated from culture extracts of Penicillium islandicum. Both toxins had a molecular formula of C16H15O2N2Cl, and physical and chemical analyses indicated that they were indole alkaloids. LD50 of toxin A was about 75-125 mg/kg in day-old cockerels. Insufficient toxin B was available to determine accurate LD50 values. Toxin A moderately inhibited growth of wheat coleoptiles but did not inhibit growth of week-old intact corn and bean plants. Toxin B showed no plant-growth inhibition. 相似文献
604.
605.
Three families with late-onset 21-hydroxylase deficiency were studied. Homozygous females presented with symptoms of mild hyperandrogenism such as acne, hirsutism, oligomenorrhea and menometrorrhagia. A homozygous male was asymptomatic and had reached normal adult height. The diagnosis of 21-hydroxylase deficiency was based upon markedly elevated responses of plasma 17-hydroxyprogesterone during a short (30-min) ACTH infusion test. The propositi of two of the families were diagnosed despite long-standing glucocorticoid therapy and adrenal suppression by using a prolonged (48-hour) ACTH infusion. Heterozygotes of late-onset 21-hydroxylase deficiency had mildly elevated 17-hydroxy-progesterone responses to ACTH. Late-onset 21-hydroxylase deficiency was inherited as an autosomal recessive trait with close linkage to the histocompatibility leukocyte antigens. The B14 haplotype was present in all affected members. One affected female had a daughter with classic, salt-losing 21-hydroxylase deficiency. Mixed heterozygosity of this patient for a classic and a late-onset 21-hydroxylase deficiency allele may have caused the classic phenotype in her daughter (homozygote for 2 classic alleles). 相似文献
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609.
Temporal studies of germ-tube forming yeast cells of Candida albicans by scanning and transmission electron microscopy indicate that extensive vacuolation and possibly also cell wall changes may cause walls of the parent yeast cell to collapse during specimen preparation. This collapse does not occur in cells which have been grown in conditions that suppress germ tube formation and have undergone the same preparative treatment. 相似文献