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31.
Almost by definition, learning and the effect of stress on learning represent modifications of existing neuronal circuitry. Under some circumstances, this modification can be measured electrophysiologically. One such measure of plasticity is long-term potentiation (LTP), a long-lasting increase in synaptic efficacy following brief exposure to tetanic stimulation. In 1987, Foy et al. reported that hippocampal LTP was impaired by exposure to inescapable shock. We have recent evidence that the impairment in LTP can be prevented by allowing the animal to learn to escape the shock (Shors et al., 1989), indicating that the stress effect is to some extent mediated by "psychological" variables. Regardless of LTP's putative role in learning and memory processes, such a stress-induced decrease in neuronal plasticity is likely to have profound effects on the behaving organism.  相似文献   
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OBJECTIVES: We explore the policy implications of probabilistic sensitivity analysis in cost-effectiveness analysis by applying simulation methods to a decision model. METHODS: We present the multiway sensitivity analysis results of a study of the cost-effectiveness of vaccination against pneumococcal bacteremia in the elderly. We then execute a probabilistic sensitivity analysis of the cost-effectiveness ratio by specifying posterior distributions for the uncertain parameters in our decision analysis model. In order to estimate probability intervals, we rank the numerical values of the simulated incremental cost-effectiveness ratios (ICERs) to take into account preferences along the cost-effectiveness plane. RESULTS: The 95% probability intervals for the ICER were generally much narrower than the difference between the best case and worst case results from a multiway sensitivity analysis. Although the multiway sensitivity analysis had indicated that, in the worst case, vaccination in the 85 and older age group was not acceptable from a policy standpoint, probabilistic methods indicated that the cost-effectiveness of vaccination was below $50,000 per quality-adjusted life-year in greater than 92% of the simulations and below $100,000 in greater than 95% of the simulations. CONCLUSIONS: Probabilistic methods can supplement multiway sensitivity analyses to provide a more comprehensive picture of the uncertainty associated with cost-effectiveness ratios and thereby inform policy decisions.  相似文献   
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AIM: To investigate the role of women general practitioners (GPs) in New Zealand. METHOD: A five-page questionnaire was posted to 200 randomly selected women GPs from throughout New Zealand. One follow-up mailing was sent. RESULTS: A response rate of 79% was achieved. Twenty-four percent of women GPs work less than 5/10 but 46% earn less than $40000. Forty-eight percent of women GPs' partners also earn less than $40000. The most common reason for working part-time was parenting responsibilities. Eighty-seven percent are married or live with a partner, 77% have children, 48% have preschool-aged children. Only 15% have Membership of the RNZCGP and 57% are owner or partner in their practice. CONCLUSION: Women GPs suffer both professional and financial difficulties because of their dual motherhood/professional roles.  相似文献   
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BackgroundCommunicating about medications across transitions of care is important in older patients who frequently move between health care settings. While there is increasing interest in understanding patient communication across transitions of care, little is known about older patients'' involvement in formal and informal modes of communication regarding managing medications.ObjectiveThe aim of this paper was to explore how older patients participated in managing their medications across transitions of care through formal and informal modes of communication.MethodsThe study was conducted across two metropolitan hospitals: an acute hospital and a geriatric rehabilitation hospital in metropolitan Melbourne, Australia. A focused ethnographic design was used involving semi‐structured interviews (n = 50), observations (203 h) and individual interviews or focus groups (n = 25). Following thematic analysis, data were analysed using Fairclough''s Critical Discourse Analysis.ResultsData analysis revealed two major discursive practices, which comprised of an interplay between formal and informal communication and environmental influences on formal and informal communication. Self‐created patient notes were used by older patients to initiate informal discussion with health professionals about medication decisions, which challenged traditional unequal power relations between health professionals and patients. Formal prompts on electronic medication administration records facilitated the continuous information discourse about patients'' medications across transitions of care and encouraged health professionals to seek out older patients'' preferences through informal bedside interactions. Environmental influences on communication comprised health professionals'' physical movements across private and public spaces in the ward, their distance from older patients at the bedside and utilization of the computer systems during patient encounters.ConclusionOlder patients'' self‐created medication notes enabled them to take on a more active role in formal and informal medication communication across transitions of care. Older patients and family members did not have continuous access to information about medication changes during their hospital stay and systems often failed to address older patients'' key concerns about their medications, which hindered their active involvement in formal and informal communication.Patient or Public ContributionOlder adults, family members and health professionals volunteered to be interviewed and observed.  相似文献   
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(1) Background: The aim of this study was to evaluate the effectiveness of a three-component nutrition, sleep, and physical activity (PA) program on cardiorespiratory fitness, body composition, and health behaviors in overweight airline pilots. (2) Methods: A parallel group study was conducted amongst 125 airline pilots. The intervention group participated in a 16-week personalized healthy eating, sleep hygiene, and PA program. Outcome measures of objective health (maximal oxygen consumption (VO2max), body mass, skinfolds, girths, blood pressure, resting heart rate, push-ups, plank hold) and self-reported health (weekly PA, sleep quality and duration, fruit and vegetable intake, and self-rated health) were collected at baseline and post-intervention. The wait-list control completed the same assessments. (3) Results: Significant group main effects in favor of the intervention group were found for all outcome measures (p < 0.001) except for weekly walking (p = 0.163). All objective health measures significantly improved in the intervention group when compared to the control group (p < 0.001, d = 0.41–1.04). Self-report measures (moderate-to-vigorous PA, sleep quality and duration, fruit and vegetable intake, and self-rated health) significantly increased in the intervention group when compared to the control group (p < 0.001, d = 1.00–2.69). (4) Conclusion: Our findings demonstrate that a personalized 16-week healthy eating, PA, and sleep hygiene intervention can elicit significant short-term improvements in physical and mental health outcomes among overweight airline pilots. Further research is required to examine whether the observed effects are maintained longitudinally.  相似文献   
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