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A cohort study of tobacco use,diet, occupation,and lung cancer mortality   总被引:1,自引:0,他引:1  
In 1966, a cohort of White males aged 35 or over, who were policy-holders with the Lutheran Brotherhood Insurance Society (United States), completed a mail questionnaire on tobacco use, diet, and demographic characteristics. During the 20 years of follow-up, 219 lung cancer deaths occurred. Besides the strong relationship with cigarette smoking, we observed an effect on lung cancer risk among current users of cigars or pipes who were nonsmokers of cigarettes (relative risk [RR]=3.5, 95 percent confidence interval[CI]=1.0–12.6) or who were past/occasional users of cigarettes (RR=2.7, CI=1.4–5.3). In addition, elevated risks (from 1.5 to 2.6) of lung cancer were found among craftsmen and laborers, with the highest risks among subjects who worked in the mining or manufacturing industry. No association between current (as of 1966) use of beer or hard liquor and lung cancer was observed, although past users were at elevated risk. An inverse association between lung cancer and intake of fruits was observed, and risks of lung cancer were lower among persons in the highest dietary intake quintiles of vitamins A and C. Except for oranges, however, none of the inverse associations with fruits or dietary nutrients had statistically significant trends. The findings from this cohort study add to the evidence of an adverse effect of cigar/pipe smoking and possibly protective effect of dietary factors on lung cancer risk.  相似文献   
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PURPOSE: The U.S. Department of Veterans Affairs (VA) supports 8,700 resident positions nationally to enhance quality of care for veterans and to educate physicians. This study sought to establish a yearly quality indicator to identify and follow strengths and opportunities for improvement in VA clinical training programs. METHOD: In March 2001, the VA Learners' Perceptions Survey, a validated 57-item questionnaire, was mailed to 3,338 residents registered at 130 VA facilities. They were asked to rate their overall satisfaction with the VA clinical training experience and their satisfaction in four domains: faculty/preceptor, learning, working, and physical environments using a five-point Likert scale. Questionnaires were received from 1,775 residents (53.2%). A full analysis was conducted using 1,436 of these questionnaires, whose respondents were categorized in four training programs: medicine (n = 706), surgery (n = 291), subspecialty (n = 266), and psychiatry (n = 173). RESULTS: On a scale of 0 to 100, residents gave their clinical training experience an average score of 79. Eighty-four percent would have recommended VA training to peers, and 81% would have chosen VA training again. Overall, 87% were satisfied with their faculty/preceptors, 78% with the learning environment, and 67% with the working and physical environments. The survey was sensitive to differences in satisfaction among the trainee groups, with residents in internal medicine (IM) the least satisfied. CONCLUSION: The VA Learners' Perceptions Survey is the first validated survey to address comprehensive satisfaction issues in clinical training. The survey highlights strengths and opportunities for improvement in VA clinical training and is the first step toward improving education.  相似文献   
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OBJECTIVE: The present study tested the hypothesis that cortical electroencephalographic (EEG) rhythms. change across normal elderly (Nold), mild cognitive impairment (MCI), and Alzheimer's disease (AD) subjects as a function of the global cognitive level. METHODS: Resting eyes-closed EEG data were recorded in 155 MCI, 193 mild AD, and 126 age-matched Nold subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. RESULTS: Occipital delta and alpha 1 sources in parietal, occipital, temporal, and 'limbic' areas had an intermediate magnitude in MCI subjects compared to mild AD and Nold subjects. These five EEG sources presented both linear and nonlinear (linear, exponential, logarithmic, and power) correlations with the global cognitive level (as revealed by mini mental state examination score) across all subjects. CONCLUSIONS: Cortical EEG rhythms change in pathological aging as a function of the global cognitive level. SIGNIFICANCE: The present functional data on large populations support the 'transitional hypothesis' of a shadow zone across normality, pre-clinical stage of dementia (MCI), and AD.  相似文献   
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Systolic and diastolic blood pressures were measured on 254 monozygotic (MZ) and 260 dizygotic (DZ) male twin pairs, during middle age (average age 48 years) and at two later age points. Genetic and environmental components of covariation were modeled by time series. For both measures, shared environmental influences were absent and specific environmental influences were largely time-specific. Although heritability was about 0.5 at each time point, genetic variation present at middle age contributed only about 60% to that present 9 years later, the remaining 40% being new. Fifteen years later, at the third time point, no new genetic variation was evident, variation in individual differences being entirely attributable to genetic differences laid down at the two earlier ages. © 1993 Wiley-Liss, Inc.  相似文献   
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Background: A growing body of research suggests that older exercisers prefer to exercise alone rather than in group-based settings. One limitation of these studies, however, has been that researchers have failed to take into account the age-related characteristics of groups when asking adults about their preferences for exercise settings.Purpose: The overall purpose of this study was to examine the exercise preferences of 947 adults for involvement in standard exercise classes populated by participants from various categories across the age spectrum.Results: The results revealed that when faced with the prospect of exercising with considerably older or younger exercisers, participants found such an exercise context to be largely unappealing. However, in accordance with the basic tenets of self-categorization theory, the results revealed that older and younger adults alike express a positive preference for exercising in standard exercise classes comprised of similarly aged participants.Conclusions: The findings of this study challenge a growing call for exercise interventions for older adults to be primarily directed at the individual-level, and suggest that group-related intervention strategies may indeed be attractive to older exercisers.  相似文献   
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ABSTRACT: On March 11–12, 1996, a workshop on how to implement new adolescent immunization (AI) recommendations was held in Atlanta, Ga. Sponsored by the Centers for Disease Control and Prevention, it was a collaborative effort of the National Immunization Program, the Division of Adolescent and School Health/National Center for Chronic Disease Prevention and Health Promotion, and the Hepatitis Branch/National Center for Infectious Diseases. The workshop brought together organizations and individuals interested in adolescent health and immunizations so they could address how new Al recommendations can be implemented most effectively. This article offers an overview of their discussions and suggestions, including issues of cooperation, education, legislation, and Al program development among health provider organizations, health departments, schools, community groups and various other agencies relating to adolescent health services.  相似文献   
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Traumatic anterior shoulder instability has been shown to be associated with a spectrum of capsulolabral pathology, including separation of the labrum (Bankart lesion), capsular rupture, and humeral avulsion of the glenohumeral ligaments (HAGL lesion). We describe a case of combined Bankart and HAGL lesions, a condition that has not been described before. Careful anatomic repair of both components of this bipolar capsular injury resulted in an excellent outcome.  相似文献   
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