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81.
张婵 《国外科技新书评介》2006,(5):23-24
这是一本涵盖了电子学、计算学、电信学及传媒学词汇的词典。第三版较上一版本增加了约9000条德英双语词条。 相似文献
82.
D. G. Perrin W. Chan E. Cutz A. Madapallimattam M. J. Sole 《Cellular and molecular life sciences : CMLS》1986,42(5):562-564
Summary By immunocytochemistry serotonin was localized in the chief cells of the carotid body in human infants. Radioenzymatic measurement of the serotonin concentration revealed that it represents a significant proportion of the total amine content of the carotid body. 相似文献
83.
Bombesin,calcitonin and leu-enkephalin immunoreactivity in endocrine cells of human lung 总被引:13,自引:0,他引:13
Summary By immunohistochemistry, bombesin, calcitonin and leu-enkephalin was localized in endocrine cells of human lungs from various age groups. It is suggested that at least 3 different peptide containing endocrine cells may be present in human lung.Acknowledgments. The authors thank Dr Camille Vaillant, University of Liverpool, for advice with immunohistochemical methods and Dr G. Dockray for his generous gift of bombesin antiserum. This work has been supported by Medical Research Council of Canada (MA-7054) and Ontario Thoracic Society. 相似文献
84.
A. W. K. Chan Donna L. Schanley Florence W. Leong 《Cellular and molecular life sciences : CMLS》1980,36(7):859-860
Summary The effects of chronic administration of 2 types of liquid diets on brain thiamine pyrophosphate (TPP) levels have been investigated. With the Lieber-DeCarli diet, rats in the control group had significantly lower TPP levels compared with those of the ethanol group. The Nutrament diet used in mice was apparently adequate in the thiamine supply.Acknowledgment. The authors are thankful to Dr Hebe Greizerstein for her review and comments on this mansucript. 相似文献
85.
86.
Campbell CD Ogburn EL Lunetta KL Lyon HN Freedman ML Groop LC Altshuler D Ardlie KG Hirschhorn JN 《Nature genetics》2005,37(8):868-872
Population stratification occurs in case-control association studies when allele frequencies differ between cases and controls because of ancestry. Stratification may lead to false positive associations, although this issue remains controversial. Empirical studies have found little evidence of stratification in European-derived populations, but potentially significant levels of stratification could not be ruled out. We studied a European American panel discordant for height, a heritable trait that varies widely across Europe. Genotyping 178 SNPs and applying standard analytical methods yielded no evidence of stratification. But a SNP in the gene LCT that varies widely in frequency across Europe was strongly associated with height (P < 10(-6)). This apparent association was largely or completely due to stratification; rematching individuals on the basis of European ancestry greatly reduced the apparent association, and no association was observed in Polish or Scandinavian individuals. The failure of standard methods to detect this stratification indicates that new methods may be required. 相似文献
87.
Clayton DG Walker NM Smyth DJ Pask R Cooper JD Maier LM Smink LJ Lam AC Ovington NR Stevens HE Nutland S Howson JM Faham M Moorhead M Jones HB Falkowski M Hardenbol P Willis TD Todd JA 《Nature genetics》2005,37(11):1243-1246
The main problems in drawing causal inferences from epidemiological case-control studies are confounding by unmeasured extraneous factors, selection bias and differential misclassification of exposure. In genetics the first of these, in the form of population structure, has dominated recent debate. Population structure explained part of the significant +11.2% inflation of test statistics we observed in an analysis of 6,322 nonsynonymous SNPs in 816 cases of type 1 diabetes and 877 population-based controls from Great Britain. The remainder of the inflation resulted from differential bias in genotype scoring between case and control DNA samples, which originated from two laboratories, causing false-positive associations. To avoid excluding SNPs and losing valuable information, we extended the genomic control method by applying a variable downweighting to each SNP. 相似文献
88.
Ross AJ May-Simera H Eichers ER Kai M Hill J Jagger DJ Leitch CC Chapple JP Munro PM Fisher S Tan PL Phillips HM Leroux MR Henderson DJ Murdoch JN Copp AJ Eliot MM Lupski JR Kemp DT Dollfus H Tada M Katsanis N Forge A Beales PL 《Nature genetics》2005,37(10):1135-1140
The evolutionarily conserved planar cell polarity (PCP) pathway (or noncanonical Wnt pathway) drives several important cellular processes, including epithelial cell polarization, cell migration and mitotic spindle orientation. In vertebrates, PCP genes have a vital role in polarized convergent extension movements during gastrulation and neurulation. Here we show that mice with mutations in genes involved in Bardet-Biedl syndrome (BBS), a disorder associated with ciliary dysfunction, share phenotypes with PCP mutants including open eyelids, neural tube defects and disrupted cochlear stereociliary bundles. Furthermore, we identify genetic interactions between BBS genes and a PCP gene in both mouse (Ltap, also called Vangl2) and zebrafish (vangl2). In zebrafish, the augmented phenotype results from enhanced defective convergent extension movements. We also show that Vangl2 localizes to the basal body and axoneme of ciliated cells, a pattern reminiscent of that of the BBS proteins. These data suggest that cilia are intrinsically involved in PCP processes. 相似文献
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90.