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71.
Thirty Type A males and 30 Type A females were administered an expanded version of the Structured Interview designed to assess 11 Type A subcomponents. The purpose was to determine whether males and females follow different subcomponent routes in achieving their Type A status. As predicted, males scored higher than females on two of four anger-related variables. Contrary to prediction, males scored higher than females on the subcomponent of exaggerated social control. These findings were interpreted as providing some support for the notion of differing gender-related subcomponent routes for achieving Type A status. These findings also may have implications for the higher incidence of coronary heart disease in high TABP males vs. females.  相似文献   
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European Archives of Oto-Rhino-Laryngology - A multidisciplinary team (MDT) approach to cancer management is gold-standard. With an increasing disease incidence and growing research into human...  相似文献   
73.
Maturing thymocytes enter the thymic medulla, where they encounter numerous self‐antigens presented by antigen presenting cells (APCs). Those thymocytes that are strongly self‐reactive undergo either negative selection or diversion into the regulatory T‐cell lineage. Although the majority of the proteome is expressed in the medulla, many self‐antigens are expressed by only a minor fraction of medullary APCs; thus, thymocytes must efficiently enter the medulla and scan APCs to ensure central tolerance. Chemokine receptors promote lymphocyte migration, organization within tissues, and interactions with APCs in lymphoid organs. The chemokine receptor EBI2 governs localization of T cells, B cells, and dendritic cells (DCs) during immune responses in secondary lymphoid organs. However, the role of EBI2 in thymocyte development has not been elucidated. Here, we demonstrate that EBI2 is expressed by murine CD4+ single positive (CD4SP) thymocytes and thymic DCs. EBI2 deficiency alters the TCR repertoire, but does not grossly impact thymocyte cellularity or subset distribution. EBI2 deficiency also impairs negative selection of OT‐II TCR transgenic thymocytes responding to an endogenous self‐antigen. Two‐photon imaging revealed that EBI2 deficiency results in reduced migration and impaired medullary accumulation of CD4SP thymocytes. These data identify a role for EBI2 in promoting efficient thymic central tolerance.  相似文献   
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Responses to a questionnaire on acquired immunodeficiency syndrome (AIDS) returned by patients of the Louisiana State University School of Dentistry were compared with responses to an AIDS questionnaire administered by the National Center for Health Statistics (NCHS). Although the questionnaire in this study was not patterned after that used by NCHS, some of the questions were either similar or directly opposite in content. Response patterns were compared and contrasted. In addition, those response patterns in Part I which are significantly different on the basis of demographic characteristics were compared with their counterparts in the NCHS survey.  相似文献   
75.
We explored relationships between decline in cognitive processing speed (CPS) and change in frontal lobe MRI/MRS-based indices of cerebral integrity in 38 healthy adults (age 57–90 years). CPS was assessed using a battery of four timed neuropsychological tests: Grooved Pegboard, Coding, Symbol Digit Modalities Test and Category Fluency (Fruits and Furniture). The neuropsychological tests were factor analyzed to extract two components of CPS: psychomotor (PM) and psychophysical (PP). MRI-based indices of cerebral integrity included three cortical measurements per hemisphere (GM thickness, intergyral and sulcal spans) and two subcortical indices (fractional anisotropy (FA), measured using track-based spatial statistics (TBSS), and the volume of hyperintense WM (HWM)). MRS indices included levels of choline-containing compounds (GPC + PC), phosphocreatine plus creatine (PCr + Cr), and N-acetylaspartate (NAA), measured bilaterally in the frontal WM bundles. A substantial fraction of the variance in the PM-CPS (58%) was attributed to atrophic changes in frontal WM, observed as increases in sulcal span, declines in FA values and reductions in concentrations of NAA and choline-containing compounds. A smaller proportion (20%) of variance in the PP-CPS could be explained by bilateral increases in frontal sulcal span and increases in HWM volumes.  相似文献   
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Previous research has established that social anxiety occurs at different rates in African American and European American populations (Grant et al., 2005), while psychometric investigations of widely used measures of psychopathology show differences in factor structure based on ethnic background (Carter et al., 1999, Chapman et al., 2009b). The current study examined response characteristics of 1276 African American and European American undergraduates completing the Fear of Negative Evaluation and Social Avoidance and Distress Scales (Watson & Friend, 1969). Confirmatory factor analyses failed to demonstrate factorial invariance in the two ethnic samples, and Wald tests suggested several items on both measures be dropped for African Americans. Results suggest the FNE and SAD operate differently across ethnic groups. Implications for the cross-cultural measurement of social anxiety and the importance of continued rigorous psychometric inquiry of commonly used measures are discussed.  相似文献   
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Quinol:fumarate reductase (QFR) is a membrane protein complex that couples the reduction of fumarate to succinate to the oxidation of quinol to quinone, in a reaction opposite to that catalyzed by the related enzyme succinate:quinone reductase (succinate dehydrogenase). In the previously determined structure of QFR from Wolinella succinogenes, the site of fumarate reduction in the flavoprotein subunit A of the enzyme was identified, but the site of menaquinol oxidation was not. In the crystal structure, the acidic residue Glu-66 of the membrane spanning, diheme-containing subunit C lines a cavity that could be occupied by the substrate menaquinol. Here we describe that, after replacement of Glu-C66 with Gln by site-directed mutagenesis, the resulting mutant is unable to grow on fumarate and the purified enzyme lacks quinol oxidation activity. X-ray crystal structure analysis of the Glu-C66-->Gln variant enzyme at 3.1-A resolution rules out any major structural changes compared with the wild-type enzyme. The oxidation-reduction potentials of the heme groups are not significantly affected. We conclude that Glu-C66 is an essential constituent of the menaquinol oxidation site. Because Glu-C66 is oriented toward a cavity leading to the periplasm, the release of two protons on menaquinol oxidation is expected to occur to the periplasm, whereas the uptake of two protons on fumarate reduction occurs from the cytoplasm. Thus our results indicate that the reaction catalyzed by W. succinogenes QFR generates a transmembrane electrochemical potential.  相似文献   
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