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排序方式: 共有152条查询结果,搜索用时 15 毫秒
41.
Kopp JB Smith MW Nelson GW Johnson RC Freedman BI Bowden DW Oleksyk T McKenzie LM Kajiyama H Ahuja TS Berns JS Briggs W Cho ME Dart RA Kimmel PL Korbet SM Michel DM Mokrzycki MH Schelling JR Simon E Trachtman H Vlahov D Winkler CA 《Nature genetics》2008,40(10):1175-1184
The increased burden of chronic kidney and end-stage kidney diseases (ESKD) in populations of African ancestry has been largely unexplained. To identify genetic variants predisposing to idiopathic and HIV-1-associated focal segmental glomerulosclerosis (FSGS), we carried out an admixture-mapping linkage-disequilibrium genome scan on 190 African American individuals with FSGS and 222 controls. We identified a chromosome 22 region with a genome-wide logarithm of the odds (lod) score of 9.2 and a peak lod of 12.4 centered on MYH9, a functional candidate gene expressed in kidney podocytes. Multiple MYH9 SNPs and haplotypes were recessively associated with FSGS, most strongly a haplotype spanning exons 14 through 23 (OR = 5.0, 95% CI = 3.5-7.1; P = 4 x 10(-23), n = 852). This association extended to hypertensive ESKD (OR = 2.2, 95% CI = 1.5-3.4; n = 433), but not type 2 diabetic ESKD (n = 476). Genetic variation at the MYH9 locus substantially explains the increased burden of FSGS and hypertensive ESKD among African Americans. 相似文献
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Prodigiosin condensing enzyme (PCE) activities were present in Serratia marcescens wild type 08, mutants OF, WF and 9-3-3. Their specific activities exhibited different maxima and at different times during the late log phase or the early stationary phase of cell growth. The levels of prodigiosin and its precursors also showed a significant increase at this period. The results support that prodigiosin and/or its precursors are secondary metabolites. The ubiquity of the PCE activity in mutants deficient in prodigiosin biosynthesis suggest that this particular enzyme may also be present in non-pigmented clinical isolates. 相似文献
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Y. W. Cho M. Akbari-Fard E. J. Dugge 《Cellular and molecular life sciences : CMLS》1966,22(4):242-244
Zusammenfassung
Escherichia coli-Endotoxin (1 mg per kg) wurde in die Ohrvene von Kaninchen injiziert: Die Succinat-dehydrogenase- und Cytochromoxydase-Aktivität in den Mitochondrien des Herzmuskels wurde nach 15 min verändert. Es ist wahrscheinlich, dass das Endotoxin sowohl auf das Herz, als auch auf die peripheren Gefässe direkt wirkt.
This study was supported by the Research Grant HE-09016 from the National Heart Institute, US Public Health Service; and the General Research Support Funds from the Philadelphia General Hospital. 相似文献
This study was supported by the Research Grant HE-09016 from the National Heart Institute, US Public Health Service; and the General Research Support Funds from the Philadelphia General Hospital. 相似文献
46.
Summary Zinc sulphate pretreatment i.p. produces dose-related reductions in stress ulcer incidence in pylorus-occluded rats. The associated increases in gastric wall mucus, in stressed and nonstressed animals, suggest that a similar effect may contribute to its ulcer-reducing ability in man. 相似文献
47.
Y. W. Cho 《Cellular and molecular life sciences : CMLS》1965,21(8):440-441
Zusammenfassung Nach kurzfristiger extrakorporaler Zirkulation beim Hund wurden Cytochrom-Oxydase-Aktivität und NADH2-Oxydationsrate in den Mitochondrien des Herzmuskels im Vergleich zu Kontrolltieren vermindert gefunden.
This study was supported by Research Grant HE-09016 from the National Institutes of Health, U.S. Public Health Service. 相似文献
This study was supported by Research Grant HE-09016 from the National Institutes of Health, U.S. Public Health Service. 相似文献
48.
Carlton JM Angiuoli SV Suh BB Kooij TW Pertea M Silva JC Ermolaeva MD Allen JE Selengut JD Koo HL Peterson JD Pop M Kosack DS Shumway MF Bidwell SL Shallom SJ van Aken SE Riedmuller SB Feldblyum TV Cho JK Quackenbush J Sedegah M Shoaibi A Cummings LM Florens L Yates JR Raine JD Sinden RE Harris MA Cunningham DA Preiser PR Bergman LW Vaidya AB van Lin LH Janse CJ Waters AP Smith HO White OR Salzberg SL Venter JC Fraser CM Hoffman SL Gardner MJ Carucci DJ 《Nature》2002,419(6906):512-519
Species of malaria parasite that infect rodents have long been used as models for malaria disease research. Here we report the whole-genome shotgun sequence of one species, Plasmodium yoelii yoelii, and comparative studies with the genome of the human malaria parasite Plasmodium falciparum clone 3D7. A synteny map of 2,212 P. y. yoelii contiguous DNA sequences (contigs) aligned to 14 P. falciparum chromosomes reveals marked conservation of gene synteny within the body of each chromosome. Of about 5,300 P. falciparum genes, more than 3,300 P. y. yoelii orthologues of predominantly metabolic function were identified. Over 800 copies of a variant antigen gene located in subtelomeric regions were found. This is the first genome sequence of a model eukaryotic parasite, and it provides insight into the use of such systems in the modelling of Plasmodium biology and disease. 相似文献
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Haploinsufficiency of protamine-1 or -2 causes infertility in mice 总被引:22,自引:0,他引:22
Protamines are the major DNA-binding proteins in the nucleus of sperm in most vertebrates and package the DNA in a volume less than 5% of a somatic cell nucleus. Many mammals have one protamine, but a few species, including humans and mice, have two. Here we use gene targeting to determine if the second protamine provides redundancy to an essential process, or if both protamines are necessary. We disrupted the coding sequence of one allele of either Prm1 or Prm2 in embryonic stem (ES) cells derived from 129-strain mice, and injected them into blastocysts from C57BL/6-strain mice. Male chimeras produced 129-genotype sperm with disrupted Prm1 or Prm2 alleles, but failed to sire offspring carrying the 129 genome. We also found that a decrease in the amount of either protamine disrupts nuclear formation, processing of protamine-2 and normal sperm function. Our studies show that both protamines are essential and that haploinsufficiency caused by a mutation in one allele of Prm1 or Prm2 prevents genetic transmission of both mutant and wild-type alleles. 相似文献