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61.
Self-efficacy in weight management   总被引:10,自引:0,他引:10  
Self-efficacy is an important mediating mechanism in advancing understanding of the treatment of obesity. This study developed and validated the Weight Efficacy Life-Style Questionnaire (WEL), improving on previous studies by the use of clinical populations, cross-validation of the initial factor analysis, exploration of the best fitting theoretical model of self-efficacy, and examination of change in treatment. The resulting 20-item WEL consists of five situational factors: Negative Emotions, Availability, Social Pressure, Physical Discomfort, and Positive Activities. A hierarchical model was found to provide the best fit to the data. Results from two separate clinical treatment studies (total N = 382) show that the WEL is sensitive to changes in global scores as well as to a subset of the five situational factor scores. Treatment programs may be incomplete if they change only a subset of the situational dimensions of self-efficacy. Theoretical and clinical implications are discussed.  相似文献   
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Using radio-biotelemetry, the timecourse of recovery and sensitivity to ambient temperature (Ta) of the thermogenic response of methylenedioxymethamphetamine (MDMA or “Ecstasy”) was examined. Ambient temperatures of 17 and 22°C produced very different response profiles, with the lower temperature producing a hypothermic response to 10 and 15 mg/kg doses of MDMA, and the higher temperature producing a profound hyperthermia to the same doses. Although the peak responses to the drug had subsided within 5 h of administration, residual effects, in the form of an elevation of body temperature during the “low” phase of the diurnal cycle, were present for a further 48 h. Long-lasting disruption of the thermoregulatory system following a short series of MDMA administrations (10 mg/kg once per day for 4 days) was shown by exposing the rats in the undrugged state to a thermoregulatory challenge, consisting of 60-min exposure to a Ta of 30°C, at 1 week before, and at 4 weeks and 14 weeks after the drug administration. MDMA-treated rats showed a prolonged hyperthermic response to the challenge at both post-drug intervals compared with fenfluramine-treated rats and saline-treated controls. Thus, the results indicate both that MDMA’s thermogenic effects are more sensitive to Ta than previously demonstrated, and that the serotonergic neurotoxicity of the drug may produce long-lasting changes in thermoregulatory mechanisms. Received: 7 December 1997/Final version: 23 January 1998  相似文献   
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OBJECTIVES: To compare the effect of a neuromuscular training program and a basic exercise program on postural control in figure skaters. DESIGN: Two groups; parallel design; prospective, randomized controlled trial. SETTING: Postural control laboratory, arenas, September 2001 to December 2002. PARTICIPANTS: Forty-four young, healthy figure skaters (18 years +/- 3 years). INTERVENTIONS: Participants were randomly assigned to receive a neuromuscular training program (n = 22) or a basic exercise training program (n = 22). Both programs were completed 3 times per week for 4 weeks, and each session was supervised. MAIN OUTCOME MEASUREMENTS: Participants completed baseline and postintervention measures of postural control on a force plate. Postural control was quantified as the center of pressure (CoP) path length during tests of single-limb standing balance that mimicked figure skating skills and challenged the postural control system to varying degrees. The primary outcome measure was the CoP path length observed during a landing jump test completed with eyes closed. RESULTS: The post intervention CoP path lengths during the more challenging tests were significantly (P < 0.05) lower (indicating better postural control) for the neuromuscular trained group than for the basic exercise-trained group. For the landing jump test completed with eyes closed, the percent improvement in the neuromuscular trained group was significantly greater (mean = 21.0 +/- 22.0%) than the basic exercise trained group (mean = -4.9 +/- 24.9%; P < 0.05). The magnitude of improvement in the neuromuscular-trained group ranged from approximately 1% to 21%, depending on the specific postural control test used. CONCLUSIONS: The results suggest that off-ice neuromuscular training can significantly improve postural control in figure skaters, whereas basic exercise training does not.  相似文献   
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PURPOSE: To explore maternal responsiveness in the first 2 to 4 months after delivery and to evaluate potential predictors of maternal responsiveness, including infant feeding, maternal characteristics, and demographic factors such as age, socioeconomic status, and educational level. DESIGN AND METHODS: A cross-sectional survey design was used to assess the variables of maternal responsiveness, feeding patterns, and maternal characteristics in a convenience sample of 177 mothers in the first 2 to 4 months after delivery. The 60-item self-report instrument included scales to measure maternal responsiveness, self-esteem, and satisfaction with life as well as infant feeding questions and sociodemographic items. An online data-collection strategy was used, resulting in participants from 41 U.S. states. FINDINGS: Multiple regression analysis showed that satisfaction with life, self-esteem, and number of children, but not breastfeeding, explained a significant portion of the variance in self-reported maternal responsiveness scores. In this analysis, sociodemographic variables such as age, education, income, and work status showed little or no relationship to maternal responsiveness scores. CONCLUSIONS: This study provides additional information about patterns of maternal behavior in the transition to motherhood and some of the variables that influence that transition. Satisfaction with life was a new predictor of maternal responsiveness. However, with only 15% of the variance explained by the predictors in this study, a large portion of the variance in maternal responsiveness remains unexplained. Further research in this area is needed.  相似文献   
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The authors report nine cases of endodrainage retinotomy site complications that occurred after vitreous surgery for complicated retinal detachments (RDs). Postoperative subretinal neovascularization developed in four eyes at the retinotomy drainage site. In two eyes, postoperative proliferation at a posteriorly placed endodrainage site created traction macular detachments. Redetachment due to retinotomy opening caused by postoperative drainage site proliferation developed in three eyes. The retinas of all nine eyes were eventually reattached, and vision improved from the preoperative level. These complications are related to retinal pigment epithelium and/or Bruch's membrane damage during internal subretinal fluid drainage and retinotomy endolaser photocoagulation. Careful evaluation of extrusion instruments, drainage techniques, retinotomy placement, and subsequent endolaser treatment is necessary to minimize these complications.  相似文献   
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