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131.
Health care organizations face significant performance challenges. Achieving desired results requires the highest level of partnership with independent physicians. Tufts Health Plan invited medical directors of its affiliated groups to participate in a leadership development process to improve clinical, service, and business performance. The design included performance review, gap analysis, priority setting, improvement work plans, and defining the optimum practice culture. Medical directors practiced core leadership capabilities, including building a shared context, getting physician buy-in, and managing outliers. The peer learning environment has been sustained in redesigned medical directors' meetings. There has been significant performance improvement in several practices and enhanced relations between the health plan and medical directors.  相似文献   
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Twenty-four-hour recall data from the Continuing Survey of Food Intake by Individuals (CSFII) are frequently used to estimate dietary exposure for risk assessment. Food frequency questionnaires are traditional instruments of epidemiological research; however, their application in dietary exposure and risk assessment has been limited. This article presents a probabilistic method of bridging the National Health and Nutrition Examination Survey (NHANES) food frequency and the CSFII data to estimate longitudinal (usual) intake, using a case study of seafood mercury exposures for two population subgroups (females 16 to 49 years and children 1 to 5 years). Two hundred forty-nine CSFII food codes were mapped into 28 NHANES fish/shellfish categories. FDA and state/local seafood mercury data were used. A uniform distribution with minimum and maximum blood-diet ratios of 0.66 to 1.07 was assumed. A probabilistic assessment was conducted to estimate distributions of individual 30-day average daily fish/shellfish intakes, methyl mercury exposure, and blood levels. The upper percentile estimates of fish and shellfish intakes based on the 30-day daily averages were lower than those based on two- and three-day daily averages. These results support previous findings that distributions of "usual" intakes based on a small number of consumption days provide overestimates in the upper percentiles. About 10% of the females (16 to 49 years) and children (1 to 5 years) may be exposed to mercury levels above the EPA's RfD. The predicted 75th and 90th percentile blood mercury levels for the females in the 16-to-49-year group were similar to those reported by NHANES. The predicted 90th percentile blood mercury levels for children in the 1-to-5-year subgroup was similar to NHANES and the 75th percentile estimates were slightly above the NHANES.  相似文献   
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The authors identified the number, type, and frequency of protective behaviors that undergraduate college students who consume alcohol use to prevent alcohol-related consequences. Their hypothesis was that students who engage in more types of protective behaviors with greater frequency would be less likely to experience alcohol-related consequences. Participants consisted of a randomly selected sample of 1,355 undergraduates aged 18 years and older at a large public university. Students completed a mailed questionnaire on alcohol and health behaviors in spring 2002. The findings (after adjustment for covariates) indicated that self-protective behaviors are inversely associated with alcohol-related problems for women but not for men. The influences of gender and racial and ethnic differences are considered in relation to prevention and intervention programs aimed at reducing alcohol-related consequences on college campuses.  相似文献   
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An increasing body of evidence now suggests the involvement of mitochondrial abnormalities in the etiology of neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer disease. In this Perspective, we describe a recent study that shows that treatment of human patients with the antioxidant coenzyme Q(10'), which functions in concert with certain mitochondrial enzymes, reduced the worsening of symptoms associated with PD. These findings are consistent with the hypothesis that mitochondrial dysfunction plays a role in the pathogenesis of PD and that treatments that target mitochondrial biochemistry might ameliorate the functional decline observed in patients suffering from PD.  相似文献   
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Smith SK  Tayman J 《Demography》2003,40(4):741-757
A number of studies have evaluated the accuracy of projections of the size of the total population, but few have considered the accuracy of projections by age group. For many purposes, however, the relevant variable is the population of a particular age group, rather than the population as a whole. We investigated the precision and bias of a variety of age-group projections at the national and state levels in the United States and for counties in Florida. We also compared the accuracy of state and county projections that were derived from full-blown applications of the cohort-component method with the accuracy of projections that were derived from a simpler, less data-intensive version of the method. We found that age-group error patterns are different for national projections than for subnational projections; that errors are substantially larger for some age groups than for others; that differences in errors among age groups decline as the projection horizon becomes longer; and that differences in methodological complexity have no consistent impact on the precision and bias of age-group projections.  相似文献   
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