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Responses from 93% of the women medical students enrolled in two southern medical schools in 1975-1976 indicated that wanting to serve others, desire for independence in one's work, and interest in science were strong motivations for entering medicine. These motivations also characterized men. Women, more often than men, cited the challenge of a medical career, and they showed more interest in high occupational prestige than have women medical school applicants in the past. Women reported less social support for an early decision than did their male peers. Dissatisfaction with a previous occupation frequently influenced women's choice of medicine. Although women were more likely than men to cite sources of encouragement for their decision, they were also more likely than men to have been discouraged from entering medicine.  相似文献   
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Echo phonology was originally proposed to account for obligatory coordination of manual and mouth articulations observed in several sign languages. However, previous research into the phenomenon lacks clear criteria for which components of movement can or must be copied when the articulators are so different. Nor is there discussion of which nonmanual articulators can echo manual movement. Given the prosodic properties of echoes (coordination of onset/offset and of dynamics such as speed) as well as general motoric coordination of various articulators in the human body, we expect that the mouth is not the only nonmanual articulator involved in echo phonology. In this study, we look at a fixed set of lexical items across 36 sign languages and establish that the head can echo manual movement with respect to timing and to the axis/axes of manual movement. We propose that what matters in echo phonology is the visual percept of temporally coordinated movement that repeats a salient movement property in such a way as to give the visual impression of a copy. Our findings suggest that echoes are not obligatory motor couplings of two or more articulators but may enhance phonological distinctions that are otherwise difficult to see.  相似文献   
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Cigarette smoking is a strong predictor of coronary heart disease (CHD), but much of the variance in determining which smokers will, and which will not, suffer from CHD remains unexplained. This review examines evidence of a synergistic interaction effect of smoking and elevated serum cholesterol on CHD morbidity and mortality. Evidence is also presented to support the notion that, in part, serum cholesterol, like smoking, is an index of a behavioral risk factor. Such a synergistic interaction is determined to exist, although improvements in methodology are needed to more clearly identify its magnitude. The review suggests that behavioral treatments aimed at smoking cessation and dietary modification should be focused specifically on the more than 25 million young and middle-aged Americans who smoke and have elevated serum cholesterol. In this way, such treatments may increase their effectiveness in lowering the risk of CHD (benefit) without necessarily increasing their effort (cost).  相似文献   
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