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31.
The yeast Saccharomyces cerevisiae CDC25 gene encodes a nucleotide-exchange-factor (NEF) that can convert the inactive GDP-bound state of RAS proteins to an active RAS-GTP complex. CDC25 can activate the yeast RAS proteins as well as the human H-ras protein. CDC25 is a member of a family of yeast genes that likely encode NEFs capable of regulating the RAS-related proteins found in yeast. By aligning the amino acid sequence of CDC25-related gene products we found a number of conserved motifs. Using degenerate oligonucleotides that encode these conserved sequences, we have used polymerase chain reactions to amplify fragments of mouse and human cDNAs related to the yeast CDC25 gene. We show that a chimeric molecule, part mouse and part yeast CDC25, can suppress the loss of CDC25 function in the yeast S. cerevisiae.  相似文献   
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A prospective study of 33 patients with polymyalgia rheumatica/giant cell arteritis (PMR/GCA) was undertaken, firstly, to monitor sequentially peripheral blood CD8+ lymphocyte levels and, secondly, to assess the expression of activation markers on T lymphocyte subsets. The results indicated that there was a significant decrease in absolute numbers and relative percentages of CD8+ T lymphocytes, which returned to normal ranges after approximately 24 months' treatment, and that there was an increased percentage of CD8+ lymphocytes in PMR/GCA which express HLA class II antigens.  相似文献   
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AimsDiabetes has been described as a cardiovascular disease (CVD) risk equivalent. There is evidence, however, that its impact may differ between women and men. For this reason, our study aimed to obtain gender-specific hazard ratios (HRs) comparing diabetes and CVD patients in terms of all-cause, CVD and coronary heart disease (CHD) mortality.MethodsIndividuals with diabetes (without CVD) and those with CVD (without diabetes) were examined through a systematic review of articles that provided gender-specific HRs for mortality. Searches included Medline, Embase and the Cochrane Library database (from January 1998 to December 2009) and exploded MeSH headings [cardiovascular diseases, risk, epidemiologic studies, case-control studies, cohort studies, mortality, outcome assessment (health care), sex factors, survival analysis and diabetes mellitus, type 2]. Two observers selected and reviewed the studies and hierarchical Bayesian random-effects models were used to combine HRs, thereby accommodating any between-study differences through inclusion of a between-study variance in HRs.ResultsOut of 5425 studies, nine were relevant (0.17%). CVD and CHD mortality in men was lower for diabetes alone (CVD mortality HR: 0.82, 95% CrI: 0.69–0.98; CHD mortality HR: 0.73, 95% CrI: 0.65–0.83). In contrast, rates appeared to be higher in women with diabetes alone (CVD mortality HR: 1.29, 95% CrI: 0.79–2.26; CHD mortality HR: 1.28, 95% CrI: 0.75–2.22), although wide credible intervals precluded any definitive conclusions. All-cause mortality in men was similar for diabetes and previous CVD (HR: 1.02, 95% CrI: 0.93–1.12) whereas, among women, it was at least as high and possibly higher for diabetes alone (HR: 1.25, 95% CrI: 0.89–1.76).ConclusionCompared with previous CVD, diabetes alone leads to lower CVD and CHD mortality risk in men, and similar all-cause mortality. In contrast, although further studies are needed, it is possible that diabetes leads to higher CVD, CHD and all-cause mortality in women.  相似文献   
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Apraxia of speech (AOS) is a rare, but well-defined motor speech disorder. It is characterized by irregular articulatory errors, attempts of self-correction and persistent prosodic abnormalities. Similar to aphasia, AOS is also localized to the dominant cerebral hemisphere. We report a case of Crossed Aphasia with AOS in a 48-year-old right-handed man due to an ischemic infarct in right cerebral hemisphere.  相似文献   
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