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We have used a commercially available mouse monoclonal antibody and shown it to bind specifically to cellular Ki-ras p21 proteins and not to cellular N- and Ha-ras p21 proteins. In conjunction with electrophoresis and Western blotting, this antibody can be used, with further detailing, to assess levels of the cellular Ki-ras p21 against a background of total p21s.  相似文献   
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ObjectiveThe objective of this study was to examine the sex-specific associations of mutually exclusive iron-anemia status categories with hemoglobin A1C (HbA1C) levels among U.S. Hispanics/Latinos without self-reported diabetes mellitus.MethodsBaseline cross-sectional data (7247 women and 4904 men without self-reported diabetes mellitus) from the Hispanic Community Health Study/Study of Latinos were analyzed. Per the American Diabetes Association’s defined criteria, based on HbA1C levels, the participants were categorized as having normoglycemia, prediabetes, or probable diabetes mellitus. The iron-anemia status categories were as follows: no anemia and no iron deficiency (reference), iron deficiency, iron deficiency anemia (IDA), and non-iron deficiency anemia (non-IDA). Survey multinomial logistic regression models were used to examine the sex-specific associations of iron-anemia status with HbA1C levels after adjusting for sociodemographic, lifestyle, and clinical factors.ResultsThe age-standardized prevalence of iron-anemia status categories differed by sex. Compared with those with no anemia and no iron deficiency and normoglycemia, women with IDA had higher odds of having prediabetes (odds ratio [OR], 2.18; 95% CI, 1.64-2.89) and probable diabetes mellitus (OR, 3.59; 95% CI, 1.62-7.99) based on HbA1C levels; men with non-IDA had higher odds of having probable diabetes mellitus (OR, 2.97; 95% CI, 1.13-7.78) based on HbA1C levels. All other associations did not reach statistical significance.ConclusionAmong U.S. Hispanics/Latinos without self-reported diabetes mellitus, the age-standardized prevalence of iron deficiency, IDA, and non-IDA is high and varies by sex. Women with IDA had higher odds of having prediabetes and probable diabetes mellitus, defined based on HbA1C levels. Men with non-IDA had higher odds of having probable diabetes mellitus, defined based on HbA1C levels. Iron-anemia status should be considered while interpreting elevated HbA1C levels among U.S. Hispanics/Latinos without self-reported diabetes mellitus.  相似文献   
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Sexually selected signals of individual dominance have profound effects on access to resources, mate choice and gene flow. However, why such signals should honestly reflect individual quality is poorly understood. Many such signals are known to develop under the influence of testosterone. We conducted an experiment in male house sparrows in which testosterone was manipulated independently during two periods: before the onset of the breeding season and prior to the autumn moult. We then measured the effects of these manipulations on basal metabolic rate and on the size of the chest bib, a sexually selected signal. The results demonstrate that testosterone simultaneously affects both signal development and basal metabolic rate in the house sparrow (Passer domesticus). This evidence, therefore, supports a novel conclusion: that testosterone-dependent signals act as honest indicators of male quality possibly because only high-quality individuals can sustain the energetic costs associated with signal development.  相似文献   
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Wisconsin Twin Panel.   总被引:1,自引:0,他引:1  
The Wisconsin Twin Panel was initiated in 1994 to serve a study of the development of childhood mood and behavioral disorders. Families who give birth to twins within the state of Wisconsin are recruited within 6 months of the birth. The panel currently supports three ongoing, longitudinal research projects. Research foci include studying epigenetic contributions to emotional, physical, cognitive, and motoric development of infant and toddler twins; physiological concomitants of childhood temperament; and early risk and resiliency factors related to child psychopathology. All three studies include videotaped observational assessments and biological measures.  相似文献   
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