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We provide further evidence for the two-factor structure of the 9-item Academic Expectations Stress Inventory (AESI) using confirmatory factor analysis on a sample of 289 Canadian adolescents and 310 Singaporean adolescents. Examination of measurement invariance tests the assumption that the model underlying a set of scores is directly comparable across groups. This study also examined the cross-cultural validity of the AESI using multigroup confirmatory factor analysis across both the Canadian and Singaporean adolescent samples. The results suggested cross-cultural invariance of form, factor loadings, and factor variances and covariances of the AESI across both samples. Evidence of AESI's convergent and discriminant validity was also reported. Findings from t-tests revealed that Singaporean adolescents reported a significantly higher level of academic stress arising from self expectations, other expectations, and overall academic stress, compared to Canadian adolescents. Also, a larger cross-cultural effect was associated with academic stress arising from other expectations compared with academic stress arising from self expectations.  相似文献   
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Qualitative and quantitative evaluations of the cellular components of bronchoalveolar washings of calves with experimental parainfluenza-3 virus pneumonitis and control calves were made. Calves were exposed to 10(9) TCID50 of PI-3 by intranasal aerosol exposure and bronchoalveolar cells obtained 7 days after infection by volume-controlled bronchopulmonary lavage. Transient tachypnea and pyrexia occurred in all infected calves, and virus was recoverable at 7 days from nasal swabs and lung tissue. Pulmonary lesions were typical of viral pneumonitis, characterized by patchy alveolitis and bronchiolitis with accumulations of cells and inflammatory debris. The mean total lavage cell yield was elevated in the virus-infected calves, and the percentage of neutrophils was elevated (P less than 0.05). Increased numbers of pulmonary alveolar macrophages (PAM) were also recovered but the difference was not significant. Linear regression equations showed that a decreased proportion of PAM from virus-infected animals were phagocytic. The mean initial phagocytic rates of macrophages from calves with viral pneumonitis were significantly decreased (P less than 0.05) over controls. This difference was concentration dependent and required a phagocytic stimulus in excess of 12.5 X 10(6) beads/ml. Studies of phagocytic kinetics showed that PAM from calves with viral pneumonitis had a lower Vmax than PAM from control calves, but that Km values were comparable. No differences in PAM beta-glucuronidase and acid phosphatase activity were observed. These results indicate depressed phagocytic function in PI-3 virus-inflamed lungs relative to controls. In concert with virus-induced airway lesions, such in vivo depression of PAM phagocytic functions would be expected to depress pulmonary particulate clearance and lung defense mechanisms.  相似文献   
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PURPOSE: To describe data sources and functional utility of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS) workforce database and associated map files. METHODS: Population data from the 2000 U.S. Census and current listings from the AAPOS and American Academy of Ophthalmology (AAO) databases were organized to demonstrate and analyze practitioner-to-population relationships for metropolitan statistical areas nationwide. An interactive map was developed to provide an intuitive graphical display of the data. RESULTS: A total of 749 active AAPOS members were distributed in 154 of 280 defined metropolitan statistical areas. Within these areas, a 0- to 20-year age subgroup varied from 17.8% to 42.6%, with an average of 30.4%. The AAPOS member-to-million-person ratio varied from 1.3 to 27, with higher numbers generally representing regions with population bases inadequately defined by Census Bureau statistical area definitions. Ratios for a majority of larger, better-defined areas ranged from 3 to 4 AAPOS members per million persons. Sizable areas with no AAPOS member presence were identified and tabulated. AAO members with a specified pediatric practice focus who were not AAPOS members were identified in 103 areas, possibly influencing patient choices and practitioner referrals for these regions. CONCLUSIONS: The AAPOS workforce database and related interactive map display practitioner and population data that may assist physicians and planners in targeting practice development and identifying potentially underserved areas.  相似文献   
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The purpose of this article is to review conceptual/theoretical and review/agenda setting nursing literature on the health care of racial/ethnic minority men [specifically African American/Black, Hispanic/Latino, American Indian/Alaskan Native and Asian/Pacific Islander men] in one of the four targeted areas of health disparities. CINAHL and MEDLINE computer databases were searched from 1983 to the present using a combination of manual and computer-based methods to identify the nursing literature that included any racial/ethnic men in the sample and addressed at least one of the four areas of health disparities targeted by Department of Health and Human Services (DHHS) that affect adults: heart disease, malignant neoplasms (cancer), diabetes mellitus and Human Immunodeficiency Virus (HIV)/AIDS. This review provides an overview of health disparities experienced by racial/ethnic minority men in the targeted areas and of the types of conceptual and agenda-setting articles published in scholarly nursing literature in those targeted areas.  相似文献   
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