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51.
The examination of physical environments to explain and promote physical activity is an important yet under-investigated area of research inquiry. This study explored relationships between the perceived availability of physical environmental resources and the perceived importance of these resources in relation to physical activity levels amongst youth. A self-report questionnaire was completed by 610 students (mean age = 15.5 years old; 62% female participants) from four high schools (grades 9-12) in rural Alberta, Canada. Perceived physical environment constructs explained 5% of the variance in physical activity, with home, neighborhood, and school as significant domains. Perceived importance constructs explained 8% of the variance in physical activity with school context showing the only significant relationship with physical activity. A hierarchical regression analysis entered sex, grade, self-efficacy, peer, family and physical education teacher relationships, as the first block and eight environmental constructs as the second block. The first block variables accounted for 22% of the variance and environmental constructs accounted for an added 4% of the variance in physical activity. Perceived importance of the school environment was the only environment variable significantly associated with physical activity (β = .14; p < .05) after taking into account the impact of these traditional predictors. These findings reinforce the need to provide and support school physical environments related to physical activity.  相似文献   
52.
OBJECTIVE: To examine psychosocial predictors of distress (mood disturbance, perceived stress, caregiver burden) in parents of children undergoing stem cell or bone marrow transplantation (BMT). METHOD: Measures of prior illness experiences, premorbid child behavior problems, family environment, social support, and parental coping behavior were obtained from the resident parents of 151 children prior to the children's admission for BMT. Parents subsequently completed assessments of their mood disturbance, perceived stress, and caregiving burden on a weekly basis through week +6 post-BMT, and then monthly through month +6 post-BMT. RESULTS: Significant changes were observed in parental distress across the course of BMT. After correcting for demographic and medical factors, several significant predictors of parental distress trajectories were identified, including prior parent and patient illness-related distress, premorbid child internalizing behavior problems, the family relationship dimensions of the family environment, and parental avoidant coping behaviors. Multivariable models were developed using a hierarchical modeling approach. The best-fit model accounted for approximately 50% of the variance in parental global distress. CONCLUSIONS: Subgroups of parents at higher risk for increased distress during the acute phase of transplant have been identified. These findings can help target parents who may be in greater need of intervention aimed at reducing transplant-related distress.  相似文献   
53.
OBJECTIVE: To examine children's competence while cycling, as demonstrated in mistakes in performance and failure to comply with safety rules. METHODS: Children in three age groups (8, 10, and 12 years) participated in a realistic yet simulated traffic environment. RESULTS: The boys' cycling speed increased steadily with age, while that of the girls increased from 8 to 10 but decreased at age 12. Most children had adequate motor control by age 10, and the youngest compensated for their less developed skills by cycling slowly and braking early at junctions. Serious mistakes, often related to the children's age and gender, consisted of the children failing to stop at signals or stopping too late, especially at short stopping range. CONCLUSIONS: There are considerable individual differences in children's cycling competence that are related to biological factors, such as age and gender, and psychological factors, such as rule compliance and choice of cycling speed.  相似文献   
54.
The Health Council of the Netherlands published a report in which the best procedure and method for recommending health‐based occupational exposure limits (OELs) for inhaled allergens were identified by evaluating the scientific state of the art. Many respiratory disorders in the workplace arise from inhalation of substances which can cause allergy. To protect workers against respiratory allergy, various preventive measures are taken, one of them being reduction of exposure by setting legally binding standards. These are based on health‐based OELs that specify a level of exposure to an airborne substance, a threshold level, below which it may reasonably be expected that there is no risk of adverse health effects. The Council is of the opinion that an OEL should prevent against allergic sensitization, as sensitization plays a crucial biological role and is a prerequisite for the development of allergy. Furthermore, the Council considers it most likely that the exposure level below which no allergic sensitization develops for most allergens is so low, that OELs are difficult to set with the current knowledge and technical feasibilities. An alternative approach is to accept exposure, which carries a small predefined risk in developing allergic sensitization. In addition, it is worth considering periodic screening of exposed workers on allergic sensitization, because timely intervention can prevent worse. The feasibility of periodic screening and what else is needed to comply with the most important criteria, should however be judged case‐by‐case.  相似文献   
55.
Self-report symptoms of anxiety are widely used in mental health and social science research as an index of current psychiatric state. Previous twin studies have suggested that genetic factors account for a significant proportion of the variance in these symptoms. To replicate and extend these findings, we examined self-report symtoms of panic-phobia and somatization in the “Virginia 30,000” twin-family sample. Model fitting applied to 80 unique relationships in the twin-family pedigree produced the following major results: (i) genetic effects were significant for both symptom factors, accounting for between 25 and 49% of the total variance, with the exception of symptoms of panic-phobia in females, where they accounted for 15–16% of the variance; (ii) familial environmental effects were absent for symptoms of somatization, while for symptoms of panic-phobia they accounted for a very small proportion of variance in males (≤1.2%) and a modest proportion in females (6–17%) (iii) spousal correlations were present for both factors, ranging from +0.05 to +0.20; (iv) genetic factors which influenced symptoms were generally the same in males and females, although their effect was greater in males; (v) heritability estimates were lower in the population-based than in the volunteer sample; and (vi) when test-retest reliability was included in the model, results suggest that genetic factors account for at least half of the stable variance for all symptom factors, except panic-phobia in females. Our results support the validity of previous twin studies of self-report symptoms of anxiety and suggest that genetic factors significantly influence these symptoms but familial-environmental factors play little or no etiologic role.  相似文献   
56.
BACKGROUND: Few studies have examined the effect on patients and staff of the physical environment in primary care facilities. AIM: To explore changes in patient and staff satisfaction, patient anxiety, and patient-doctor communication when a GP surgery moves from old premises to enhanced purpose-built accommodation. DESIGN OF STUDY: Questionnaire surveys, interviews, and focus groups pre- and post move. SETTING: An urban general practice in Bristol. METHOD: Patient questionnaires assessed anxiety (Spielberger State-Trait Anxiety Inventory; STAI), satisfaction with the environment, and communication during the consultation. Staff questionnaires assessed satisfaction with the environment and job satisfaction. Qualitative methods explored patient and staff views in more depth. RESULTS: A total of 1118 pre-move and 954 post-move patient questionnaires showed significant increases in satisfaction scores for reception/waiting areas (mean 6.46, 95% confidence interval [CI]=5.97 to 6.95) and consulting rooms (mean 3.80, 95% CI=3.44 to 4.15) in the new premises. Patients' satisfaction with patient-doctor communication also increased (mean 0.88, 95% CI=0.30 to 1.46) and anxiety scores were significantly reduced before and after the consultation in the new premises compared with the old (STAI mean difference before consultation 0.72, 95% CI=0.37 to 1.08; mean after consultation 0.37, 95% CI=0.03 to 0.72). Patients highlighted the increased space and light, more modern appearance, greater comfort, and novel works of art in the new surgery. Staff workplace satisfaction increased significantly after moving and remained higher than in the old building. CONCLUSION: This large-scale study examining the effects of a UK primary care environment on patients and staff shows that an enhanced environment is associated with improvements in patients' perception of patient-doctor communication, reduction in anxiety, and increases in patient and staff satisfaction.  相似文献   
57.
Open-field behavior was studied as a function of three classes of variables: maternal characteristics, rearing environment, and sexual experience. Mothers of experimental subjects were either handled or nonhandled in infancy. Subjects were born and reared to weaning either in maternit cages or in Hebb-type free environments and were placed after weaning into either a laboratory cage or free enviroment. Sexual experience consisted either of bearing and raising a litter or no sexual experience. The results confirmed previous findings that offspring of mothers handled in infancy arc significantly less active in the open field than the offspring of nonhandled mothers. The maternal handling variable also interacted significantly with breeding experience: for rats which had not been bred, those raised by nonhandled mothers were more active than those raised by handled mothers; for females with breeding experience the reverse was true. Overall, thosc femalcs which had reared a litter were more active and defecated more than their nonbred littermates.  相似文献   
58.
Because the mite-allergen content in homes is highly variable even in the same geographic area, we tried to determine which variables influence mite infestation. We evaluated mite-allergen content in bedding relative to housing conditions and living habits. This cross-sectional study included 108 homes. Housing conditions were assessed by an architect and living habits by a researcher specialized in social and family economics. Group I allergen level was measured on the mattress dust with monoclonal antibodies, and relative humidity (RH) was monitored in the bedroom during a 2-week period. Homes with low RH did have low mite-allergen content. In contrast, homes with intermediate RH levels had very variable mite-allergen content. Using analysis of variance and a logistic regression analysis, we were unable to identify any variable predictive of mite-allergen content. Thus, factors other than relative humidity seem to influence mite infestation. Moreover, the absence of association between mite infestation and ventilation rate might be accounted for by the gentle climate in our area with notable outdoor RH.  相似文献   
59.
刘满芬  张永龙 《医学信息》2005,18(12):1662-1663
因为数字化学习环境是未来图书馆事业的发展趋势,文章从图书馆数字化学习环境的内涵开始,分析了医院图书馆数字化学习环境建设的必要性及其现实的可行性,提出了图书馆软件环境和硬件环境的建设及两者的有机结合是医院图书馆数字化学习环境建设的重要保障。  相似文献   
60.
El Sharif N  Douwes J  Hoet PH  Doekes G  Nemery B 《Allergy》2004,59(6):623-631
BACKGROUND: A few studies have compared indoor allergens and endotoxin levels between urban and rural settings as important determinants for asthma and atopy in children. However, no study was done in the Middle East or investigated refugee camps. METHODS: As part of a nested case-control study in Ramallah in 2001, we measured house dust mite and pet allergens, as well as endotoxin in dust collected from 110 children's mattresses and living room floors. RESULTS: Geometric mean (GM) concentrations of Dermatophagoides pteronyssinus (Der p1) antigen were 4.48 microg/g in mattress dust and 1.23 microg/g floor dust. The highest Der p1 levels were seen in refugee camps. Concentrations of Dermatophagoides farinae antigen (Der f1) were much lower (<0.08 microg/g dust). Concentrations of cat allergen (Fel d1) were highest in villages, and those of dog allergen (Can f1) were highest in mattresses from cities and in floor dust from refugee camps. GM of endotoxin levels were 25.7 EU/mg in mattress dust and 49 EU/mg dust in floor dust. CONCLUSIONS: Concentrations of Der p1 were high compared to Western European countries, but were lower compared to UK and Australia. Levels of pet allergens were lower than in Western Europe. Endotoxin levels were higher compared to developed countries. Indoor environmental factors such as dampness seemed to be important determinants for allergen and endotoxin, but living habits such as lack of mattress cover appeared unimportant.  相似文献   
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