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121.
In order to investigate the body image self-perception and the prevalence of body dissatisfaction among Chinese children and adolescents, 9100 children aged 3-15 years living in four cities completed a questionnaire assessing body image self-percepts and ideals by figural stimuli. The results indicate that (1) children's body ratings started to be significantly related to their BMIs at age 5 and correlations increased with age; (2) a wide range of current body sizes was chosen by Chinese boys and girls; (3) the ideal body sizes of boys and girls selected by boys and girls, respectively, were "boys by boys">"boys by girls">"girls by boys">"girls by girls" and (4) the satisfaction, mild dissatisfaction, and moderate dissatisfaction rates were 40.1%, 36.4% and 23.5%, respectively. Differences as a function of gender and age were identified. It was concluded that the prevalence of body dissatisfaction among children and adolescents of urban China was striking, and that the Chinese boys were not immune to body dissatisfaction. 相似文献
122.
This study evaluated the characteristics of suicidal behavior (suicide attempt or suicidal ideation) among 230 consecutively admitted inpatients with schizophrenia and mood disorders in a university hospital in China. The rate of lifetime suicidal behavior was found to be significantly higher in patients with mood disorders (62.4%) than in patients with schizophrenia (38.6%). The rate of suicidal behavior was significantly higher in patients with major depressive disorder (86.8%) than those with bipolar disorders (42.6%). Patients with schizophrenia attempted suicide for the first time earlier in life than the patients with mood disorders. Mood disorder patients, especially those with major depressive disorder, had more and more serious suicide attempts than the patients with schizophrenia. 相似文献
123.
Selective age-related differences in source memory relative to item memory, and individual differences in memory performance in relation to anxiety were explored with high- and low-anxious subjects screened from normal young and elderly adults. They were read false facts about the locations of well-known and unknown sights in a male or female voice. Intentional and incidental learning instructions were administered for source memory. Selective age-related deficits in source memory were observed under both encoding conditions. Higher level of anxiety was related to lower memory performance only in the old group; this relation was stronger in source recall. The findings suggest that the presence of such selectivity is unrelated to the tradeoff between item encoding and source encoding. Anxiety affects the variability, and mediates the selectivity of age effects on episodic memory. 相似文献
124.
ERP evidence for the time course of graphic, phonological, and semantic information in Chinese meaning and pronunciation decisions 总被引:3,自引:0,他引:3
Liu Y Perfetti CA Hart L 《Journal of experimental psychology. Learning, memory, and cognition》2003,29(6):1231-1247
Two words that varied in their relationship were presented sequentially to Chinese readers who made meaning and pronunciation decisions. In the meaning task, they decided whether the words had the same meaning. In the pronunciation task, they decided whether the words had the same pronunciation. In both tasks, the word pairs represented 1 of 4 relationships: graphically similar, homophonic, semantically related, or unrelated. Event related potentials (ERP) recordings made from the onset of the 2nd word suggested a temporal unfolding of graphic, phonological, and semantic effects. Specifically, graphically-related pairs produced a smaller P200 in the pronunciation task and a smaller N400 in the meaning task. Homophones produced reduced N400 component with bilateral sources in the meaning task. 相似文献
125.
The safety and efficacy of medications for preventive treatment of migraine is the subject of current concern and investigation in health care. Two single-center, double-blind, placebo-controlled studies were conducted to evaluate the efficacy and safety of topiramate for migraine prophylaxis. Seventy patients with a diagnosis of migraine were randomly assigned to topiramate-treated and placebo groups. The studies consisted of a 4-week baseline phase, a 6-8 week titration, and 8-12 weeks of maintenance. Topiramate was titrated from an initial dose of 25 mg/day to a target dose of 100 mg BID. The primary efficacy measure, the mean 28-day migraine frequency, was lower in topiramate-treated patients than in the placebo group (3.2 versus 3.8, P=.001). Similarly, topiramate treatment resulted in a significantly greater mean reduction in migraine frequency than did placebo (1.55 versus 0.47, P=.001) and a significantly higher responder rate (35.3% versus 8.3%, P=.008). Paresthesia was the most common side effect reported with topiramate treatment. Other topiramate-associated adverse events included altered taste, memory impairment, diarrhea, and appetite suppression/weight loss. The rates of discontinuation were similar for the topiramate group (n=10) and the placebo group (n=8). These results suggest that topiramate is effective and well tolerated in the preventive treatment of migraine headaches. 相似文献
126.
A theoretical framework based on the concepts and tools of nonlinear dynamical systems is advanced to account for both the persistent and transitory changes traditionally shown for the learning and development of motor skills. The multiple time scales of change in task outcome over time are interpreted as originating from the system's trajectory on an evolving attractor landscape. Different bifurcations between attractor organizations and transient phenomena can lead to exponential, power law, or S-shaped learning curves. This unified dynamical account of the functions and time scales in motor learning and development offers several new hypotheses for future research on the nature of change in learning theory. 相似文献
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129.
In 3 experiments, the authors examined movement space-time variability as a function of the force-time properties of the initial impulse in a movement timing task. In the range of motion and movement time task conditions, peak force, initial rate of force, and force duration were manipulated either independently or in combination across a range of parameter values. The findings showed that (a) impulse variability is predicted well by the elaboration of the isometric force variability scaling functions of L. G. Carlton, K. H. Kim, Y. T. Liu, and K. M. Newell (1993) to movement, and (b) the movement spatial and temporal outcome variability are complementary and well predicted by an equation treating the variance of force and time in Newton's 2nd law as independent random variables. Collectively, the findings suggest that movement outcome variability is the product of a coherent space-time function that is driven by the nonlinear scaling of the force-time properties of the initial impulse. 相似文献
130.