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41.
Gag rules-clauses in managed care contracts that prevent physicians from disclosing information that the plan may find disparaging, but that could relate directly to the patient's health-have recently been the subject of ethical condemnation and legislative prohibition. Another serious problem in managed care contracts, trade secrets, or guidelines and quality assurance mechanisms that are imposed on physicians while their origins are shrouded in proprietary secrecy, have by contrast received little attention. Responses to these ethical challenges to the physician's integrity must involve individual physicians, managed care organizations, professional organizations, and public policymakers. 相似文献
42.
Generic utterances (e.g., "Cows say 'moo"') have 2 distinctive semantic properties: (a) Generics are generally true, unlike indefinites (e.g., "Bears live in caves" is generic; "I saw some bears in the cave" is indefinite), and (b) generics need not be true of all category members, unlike universal quantifiers (e.g., all, every, each). This article examined whether preschool children and adults appreciate both these features, using a comprehension task (Study 1) and an elicited production task (Study 2). In both tasks, 4-year-old children--like adults--treated generics as distinct from both indefinites ("some") and universal quantifiers ("all"). In contrast, 3-year-olds did not differentiate among generics, "all," and "some." By 4 years of age, generics emerge as a distinct semantic device. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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To evaluate the utility of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) as a cancer therapeutic, we created leucine zipper (LZ) forms of human (hu) and murine (mu) TRAIL to promote and stabilize the formation of trimers. Both were biologically active, inducing apoptosis of both human and murine target cells in vitro with similar specific activities. In contrast to the fulminant hepatotoxicity of LZ-huCD95L in vivo, administration of either LZ-huTRAIL or LZ-muTRAIL did not seem toxic to normal tissues of mice. Finally, repeated treatments with LZ-huTRAIL actively suppressed growth of the TRAIL-sensitive human mammary adenocarcinoma cell line MDA-231 in CB.17 (SCID) mice, and histologic examination of tumors from SCID mice treated with LZ-huTRAIL demonstrated clear areas of apoptotic necrosis within 9-12 hours of injection. 相似文献
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This research derives and tests hypotheses from two alternative conceptual models: the modified extended family model, and the changing family constraints model, which takes into account recent changes in work and family life. The hypotheses address social class differences in geographic distance and contact frequency between middle-aged children and their parents over time. Simultaneous probit models are used to analyze distance and contact as jointly determined outcomes with data from the USC Longitudinal Study of Generations and Mental Health. Results from these analyses indicate that children's 1971 educational aspirations and social class positions predict 1991 distance and contact between generations. Parents who have lower 1991 incomes, however, live farther from children and talk with them on the telephone less frequently than higher-income parents. Thus, the effects of early social class position support the modified extended family model, whereas the effects of current social class position support the changing family constraints model. 相似文献
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VL Shnyrov GG Zhadan C Cobaleda A Sagrera I Mu?oz-Barroso E Villar 《Canadian Metallurgical Quarterly》1997,341(1):89-97
The spatial and temporal pattern of expression of enhancer trap lines reporting on the wingless (wg) and engrailed (en) genes was characterized in the adult antenna of Drosophila melanogaster. The time courses of expression seen for wg and en, although different from each other, reveal a complex well-controlled pattern of temporal expression, providing evidence that regulatory mechanisms are preserved throughout the life span of the adult fly. Altering the life span demonstrates that the temporal patterns of expression of both wg and en are linked to life span. These studies suggest that the expression of wg and en in the adult antenna is controlled by age-dependent mechanisms. 相似文献
49.
T Goldman AL Hallin CM Hoffman LE Piilonen D Preston RD Bolton MD Cooper JS Frank PA Heusi GE Hogan FG Mariam HS Matis RE Mischke VD Sandberg GH Sanders U Sennhauser R Werbeck RA Williams D Grosnick SC Wright SL Wilson R Hofstadter EB Hughes MW Ritter VL Highland J McDonough 《Canadian Metallurgical Quarterly》1987,36(5):1543-1546
50.
OBJECTIVE: Cholelithiasis is a common problem in hospitals of the Peruvian Andes; however, its prevalence in Andean communities is unknown. To estimate the prevalence of gallstone disease in this locale, we conducted a cross-sectional community study in three high-altitude Peruvian rural villages (i.e., > 3000 m above sea level). METHODS: We examined 911 volunteers > 15 yr of age from three villages for gallstone disease by history and ultrasonography. Risk factors for gallstone disease were examined in 382 volunteers from one village. RESULTS: The age-adjusted prevalence of gallstone disease ranged from 4-10% in men and from 18-20% in women. Women had significantly higher age-adjusted prevalence rates than did men. The prevalence of gallstone disease increased significantly with age and decreased significantly with alcohol consumption. Although not statistically significant, we found a positive association between gallstone disease and body mass index. CONCLUSION: The results of this study indicate that gallstone disease, commonly perceived as a disease of the developed world, is also a common problem in high-altitude Peruvian communities. 相似文献