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OBJECTIVE: This report reviews the evidence that informs the role of health and mental health care providers in addressing youth smoking cessation. DESIGN: Qualitative literature review. RESULTS: Physicians do not consistently screen adolescents for tobacco use and fail to provide recommended cessation advice. Challenges to addressing smoking cessation include the need for procedures to ensure confidentiality and the existence of competing demands to provide other services. Few published studies have specifically addressed the effectiveness of clinical interventions. Interventions that require return visits or follow-up phone contacts are technically difficult to implement in this population. Successful interventions may require resources not available in nonresearch settings. Most studies have used brief clinical intervention as a control condition, making it impossible to evaluate its effectiveness. CONCLUSION: There is little evidence that supports current clinical smoking cessation guidelines for adolescents. More research is needed to develop inexpensive, efficient clinical interventions that can provide youths access to smoking cessation help. Future challenges include reorganizing clinical systems to offer greater counseling by support staff or in electronic formats and to provide effective booster messages and follow-up care in a population that is difficult to track.  相似文献   
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This study addresses the demands of alternating bimanual syncopation, a coordination mode in which the two hands move in alternation while tapping in antiphase with a metronomic tone sequence. Musically trained participants were required to engage in alternating bimanual syncopation and five other coordination modes: unimanual syncopation where taps are made (with the left or right hand) after every tone; unimanual syncopation where taps are made after every other tone; bimanual synchronization with alternating hands; unimanual synchronized tapping with every tone; and unimanual tapping with every other tone. Variability in tap timing was greatest overall for alternating bimanual syncopation, indicating that it is the most difficult. This appears to be due to instability arising from the simultaneous presence of two levels of antiphase coordination (one between the pacing sequence and the hands, the other between the two hands) rather than factors relating to movement frequency or dexterity limits of the nonpreferred hand.  相似文献   
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Following Altman's privacy regulation model, this research was based on the assumption that the relationship between achieved and desired levels of privacy is a major determinant of the experience of crowding in small groups. Further, on the basis of evidence that advancing age is associated with a chronic lack of communicative interaction, it was assumed that the achieved level of privacy among elderly persons generally is greater than that experienced by young adults. Given these assumptions, it was predicted that the crowding threshold of young adults would be significantly lower than that of older persons. To test this hypothesis, the research varied conversation distance (close, far) and density (small room, large room) and assessed the quality of communicative interaction and task performance among small groups of college-age females and retired women over 60 years of age. Results showed that task performance among younger subjects deteriorated in close interaction conditions, whereas the performance of older subjects was improved by spatial intrusion. Further, older subjects exhibited positive communication behaviors in response to close conversation, high-density conditions, while younger subjects responded either with negative communication behaviors or were unaffected by spatial restriction. Finally, the research confirmed previous findings that conversation distance is a more important determinant of the experience of crowding in small groups than physical density. The significance of the results for Altman's privacy regulation model and their implications for the study of human communication behaviors were discussed.  相似文献   
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A growing literature has observed a significant reduction in pain sensitivity among hypertensive animals and humans. It is uncertain whether a reduced sensitivity to pain can be observed in nonnotensive individuals who go on to develop high blood pressure. Blood pressure (BP) was reassessed in one hundred fifteen 19-year-old boys initially tested at age 14, when they were also presented with a pain stimulus (mechanical finger pressure). Hierarchical regression analyses indicated that information regarding pain tolerance improved prediction of changes in systolic and diastolic blood pressure beyond that afforded by differences in BP at age 14, parental history of hypertension, and body mass index. These analyses suggest that pain sensitivity may be associated with physiological processes involved in the development of sustained high blood pressure.  相似文献   
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