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91.
FS Machado EC Telles L Fouto EP da Silva N Lan?a I de Oliveira 《Canadian Metallurgical Quarterly》1996,15(6):465-71, 459
The objective of this study is to contribute to the positioning of the intravenous digital subtraction angiography (IVDSA) in the detection of morphologic abnormalities of renal arteries (RAs), susceptible to originate renovascular hypertension (RVH). The authors focus on the prevalence of RVH in the broad spectrum of systemic arterial hypertension. The definition of RVH is given and its diagnostic criteria are revisited. The angiography methods used in the evaluation of RAs morphologic abnormalities are described. 相似文献
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AC Beekman PK Wierenga HJ Woerdenbag W Van Uden N Pras AW Konings FS el-Feraly AM Galal HV Wikstr?m 《Canadian Metallurgical Quarterly》1998,64(7):615-619
Epidemiologic and public health researchers frequently include several dependent variables, repeated assessments, or subgroup analyses in their investigations. These factors result in multiple tests of statistical significance and may produce type 1 experimental errors. This study examined the type 1 error rate in a sample of public health and epidemiologic research. A total of 173 articles chosen at random from 1996 issues of the American Journal of Public Health and the American Journal of Epidemiology were examined to determine the incidence of type 1 errors. Three different methods of computing type 1 error rates were used: experiment-wise error rate, error rate per experiment, and percent error rate. The results indicate a type 1 error rate substantially higher than the traditionally assumed level of 5% (p < 0.05). No practical or statistically significant difference was found between type 1 error rates across the two journals. Methods to determine and correct type 1 errors should be reported in epidemiologic and public health research investigations that include multiple statistical tests. 相似文献
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A transcript map for the 2.8-Mb region containing the multiple endocrine neoplasia type 1 locus 总被引:1,自引:0,他引:1
97.
Pit1 is the human receptor for gibbon ape leukemia virus (GALV) and feline leukemia virus subgroup B (FeLV-B), while the related human protein Pit2 is a receptor for amphotropic murine leukemia virus (A-MuLV). The A-MuLV-related isolate 10A1 can utilize both Pit1 and Pit2 as receptors. A stretch of amino acids named region A was identified in Pit1 (residues 550 to 558 in loop 4) as critical for GALV and FeLV-B receptor function. We have here investigated the role of region A in A-MuLV and 10A1 entry. Insertion of a single amino acid in region A of mouse Pit1 resulted in a functional A-MuLV receptor, showing that region A plays a role in A-MuLV infection. Moreover, the downregulation of 10A1 receptor function by changes in region A of human Pit1 indicates that this region is also involved in 10A1 entry. Therefore, region A seems to play a role in infection by all viruses utilizing Pit1 and/or Pit2 as receptors. 相似文献
98.
TT Postolache TA Hardin FS Myers EH Turner LY Yi RL Barnett JR Matthews NE Rosenthal 《Canadian Metallurgical Quarterly》1998,155(11):1614-1616
OBJECTIVE: The authors sought to compare the degree of mood improvement after light treatment with mood improvement in the subsequent summer in patients with seasonal affective disorder. METHOD: By using the Seasonal Affective Disorder Version of the Hamilton Depression Rating Scale, the authors rated 15 patients with seasonal affective disorder on three occasions: during winter when the patients were depressed, during winter following 2 weeks of light therapy, and during the following summer. They compared the three conditions by using Friedman's analysis of variance and the Wilcoxon signed ranks test. RESULTS: The patients' scores on the depression scale were significantly higher after 2 weeks of light therapy in winter than during the following summer. CONCLUSIONS: Light treatment for 2 weeks in winter is only partially effective when compared to summer. Further studies will be necessary to assess if summer's light or other factors are the main contributors to this difference. 相似文献
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