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11.
论述了少年儿童拳击运动身体训练的可行性及重要性,分析了少年儿童不同时期的生理特征及与之相适应的拳击运动身体训练方法手段的选择,可为少年儿童拳击运动的科学化训练提供理论依据。  相似文献   
12.
本文主要对影响学校体育实施健康教育的因素进行了分类研究 ,为学校体育实施健康教育提供科学的参考依据。  相似文献   
13.
童年意象的运用是王安忆小说独树一帜的重要原因."成长中的儿童"是王安忆小说中特有的形象.以儿童形象为象征载体进行文化批判是对童年意象的出色运用.儿童视角的发掘使王安忆的小说取得了"陌生化"的审美效果,也使细节化呈现文本的艺术表达方式与文本的精神内涵完美地结合起来.儿童视角的运用还让作家能以旁观者的眼光看世界,保持了独立、警醒的创作立场.  相似文献   
14.
Children may be more susceptible to toxicity from some environmental chemicals than adults. This susceptibility may occur during narrow age periods (windows), which can last from days to years depending on the toxicant. Breathing rates specific to narrow age periods are useful to assess inhalation dose during suspected windows of susceptibility. Because existing breathing rates used in risk assessment are typically for broad age ranges or are based on data not representative of the population, we derived daily breathing rates for narrow age ranges of children designed to be more representative of the current U.S. children's population. These rates were derived using the metabolic conversion method of Layton (1993) and energy intake data adjusted to represent the U.S. population from a relatively recent dietary survey (CSFII 1994–1996, 1998). We calculated conversion factors more specific to children than those previously used. Both nonnormalized (L/day) and normalized (L/kg-day) breathing rates were derived and found comparable to rates derived using energy estimates that are accurate for the individuals sampled but not representative of the population. Estimates of breathing rate variability within a population can be used with stochastic techniques to characterize the range of risk in the population from inhalation exposures. For each age and age-gender group, we present the mean, standard error of the mean, percentiles (50th, 90th, and 95th), geometric mean, standard deviation, 95th percentile, and best-fit parametric models of the breathing rate distributions. The standard errors characterize uncertainty in the parameter estimate, while the percentiles describe the combined interindividual and intra-individual variability of the sampled population. These breathing rates can be used for risk assessment of subchronic and chronic inhalation exposures of narrow age groups of children.  相似文献   
15.
对我国普通高校学生心理健康问题的调研   总被引:3,自引:0,他引:3  
运用反映人类心理健康状况的CES-D、SAS和SCL-90自评量表的测试结果表明,我国普通高校学生的心理健康状况不容乐观,20.4%的大学生有轻度心理障碍,8.6%的学生有中度心理障碍,3.2%的学生患有心理疾病,这应当引起学校教育的高度重视和全社会的广泛关注。  相似文献   
16.
针对大学贫困生进行16PF和MMPI调查,评价贫困生心理健康状况及其影响因素。  相似文献   
17.
We describe a risk-based analytical framework for estimating traffic fatalities that combines the probability of a crash and the probability of fatality in the event of a crash. As an illustrative application, we use the methodology to explore the role of vehicle mix and vehicle prevalence on long-run fatality trends for a range of transportation growth scenarios that may be relevant to developing societies. We assume crash rates between different road users are proportional to their roadway use and estimate case fatality ratios (CFRs) for the different vehicle-vehicle and vehicle-pedestrian combinations. We find that in the absence of road safety interventions, the historical trend of initially rising and then falling fatalities observed in industrialized nations occurred only if motorization was through car ownership. In all other cases studied (scenarios dominated by scooter use, bus use, and mixed use), traffic fatalities rose monotonically. Fatalities per vehicle had a falling trend similar to that observed in historical data from industrialized nations. Regional adaptations of the model validated with local data can be used to evaluate the impacts of transportation planning and safety interventions, such as helmets, seat belts, and enforcement of traffic laws, on traffic fatalities.  相似文献   
18.
Informal caregivers of individuals with Alzheimer's disease spend a considerable amount of time providing care. In this paper, we use Grossman's health production and Becker's time allocation models to develop a model of informal care provision to elderly dementia patients. In our model, time inputs produce caregiving services, which provides utility to the caregiver, but reduces leisure. We assume that time is less productive of services on the margin as the disease progresses. In this framework, an increase in patients' disease severity does not necessarily increase informal caregiver time input. The cost of formal care establishes a reservation price for informal caregiving. When the costs of informal caregiving rise above this reservation level, the patient is institutionalized. We test empirically the effect of deterioration in the patients' condition, proxied by both disease severity and dementia problem behavior, on informal caregiving time. We find that dementia-related problem behaviors and functional limitations significantly increase inputs of informal caregiving time. Patients' problem behavior exerts a modifying effect on functional limitations, and patients' comorbidities have no effect on informal caregiving time.  相似文献   
19.
In the ten-year period from 1990 to 1999, children's consumption has increased dramatically in proportion to family income. In 85% of urban families, children's average consumption is equal to one third or more of the family's income. Resources are being directed to children's food and dietary supplements, toys, travel, computers and other electronic equipment, and educational resources. Children perceive that they have a significant influence on the family's financial decision-making. Problems related to children's consumption include indulgence in unnecessary or harmful purchases, and conspicuous consumption that cannot be sustained by the family's income. While some child-focused spending is viewed as enriching development, other expenditures may harm the family's economic well-being and foster an overly materialistic outlook among children.  相似文献   
20.
大学生就业心理障碍的成因与对策分析   总被引:6,自引:0,他引:6  
在严峻的就业形势面前,部分毕业生心理压力过大,产生了就业心理障碍,影响了他们的顺利就业。通过对大学生就业心理的研究,分析产生障碍的原因,探索克服障碍的对策措施,对促进大学生顺利就业,具有十分重要的现实意义。  相似文献   
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