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991.
ABSTRACT: BACKGROUND: This study examines the psychometric properties of 9 items on the Patient Activation component of the Medicare Current Beneficiary Survey (MCBS) that assess how patients approach and communicate with their physicians. The MCBS is a nationally representative, cross-sectional survey of Medicare beneficiaries. METHODS: We analyzed MCBS data collected in 2002 and 2005 from 15,165 adults aged 65 and older. Exploratory factor analysis was conducted using maximum likelihood to estimate a polychoric correlation matrix on the 2002 data, and confirmatory factor analysis was performed using the 2005 data. RESULTS: Exploratory factor analysis of the 2002 data showed a 2-factor solution: approach to interactions (5 items) and views about physician's healthcare communication (6 items). Findings were confirmed using the 2005 data. Items were combined to form the Patient Approach and Views toward Healthcare Communication (PAV-COM) scale (range 1 to 100; Cronbach's alpha of 0.75, and item-rest correlations between 0.33 and 0.54). Higher PAV-COM scores were associated with greater fulfillment of preventive health behaviors such as vaccinations and cancer screenings. CONCLUSIONS: The PAV-COM measure is a valid tool for assessing patient approaches and views toward communication with physicians. This measure can be used to evaluate interventions to improve patient participation during healthcare encounters.  相似文献   
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Background  

Musculoskeletal complaints influence general health status, but the relative contribution of concurrent upper and lower extremity disabilities on patient perceptions of general health is unclear.  相似文献   
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Although endoplasmic reticulum (ER) stress is a pathologic mechanism in a variety of chronic diseases, it is unclear what role it plays in chronic hypertension (HTN). Dysregulation of brain mechanisms controlling arterial pressure is strongly implicated in HTN, particularly in models involving angiotensin II (Ang II). We tested the hypothesis that ER stress in the brain is causally linked to Ang II–dependent HTN. Chronic systemic infusion of low-dose Ang II in C57BL/6 mice induced slowly developing HTN, which was abolished by co-infusion of the ER stress inhibitor tauroursodeoxycholic acid (TUDCA) into the lateral cerebroventricle. Investigations of the brain regions involved revealed robust increases in ER stress biomarkers and profound ER morphological abnormalities in the circumventricular subfornical organ (SFO), a region outside the blood-brain barrier and replete with Ang II receptors. Ang II–induced HTN could be prevented in this model by selective genetic supplementation of the ER chaperone 78-kDa glucose-regulated protein (GRP78) in the SFO. These data demonstrate that Ang II–dependent HTN is mediated by ER stress in the brain, particularly the SFO. To our knowledge, this is the first report that ER stress, notably brain ER stress, plays a key role in chronic HTN. Taken together, these findings may have broad implications for the pathophysiology of this disease.  相似文献   
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A major goal of plant biotechnology is to improve the nutritional qualities of crop plants through metabolic engineering. Melatonin is a well‐known bioactive molecule with an array of health‐promoting properties, including potent antioxidant capability. To generate melatonin‐rich rice plants, we first independently overexpressed three tryptophan decarboxylase isogenes in the rice genome. Melatonin levels were altered in the transgenic lines through overexpression of TDC1, TDC2, and TDC3; TDC3 transgenic seed (TDC3‐1) had melatonin concentrations 31‐fold higher than those of wild‐type seeds. In TDC3 transgenic seedlings, however, only a doubling of melatonin content occurred over wild‐type levels. Thus, a seed‐specific accumulation of melatonin appears to occur in TDC3 transgenic lines. In addition to increased melatonin content, TDC3 transgenic lines also had enhanced levels of melatonin intermediates including 5‐hydroxytryptophan, tryptamine, serotonin, and N‐acetylserotonin. In contrast, expression levels of melatonin biosynthetic mRNA did not increase in TDC3 transgenic lines, indicating that increases in melatonin and its intermediates in these lines are attributable exclusively to overexpression of the TDC3 gene.  相似文献   
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