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961.
In some areas where oxygenated fuel programs have been implemented, there have been widespread complaints of non-specific health effects attributed to the gasoline. There are a number of hypotheses that can account for this apparent association. This paper examines the hypothesis that the use of oxy-fuel (either oxygenated gasoline or reformulated gasoline) results in exposure of the general population to one or more chemicals at concentrations that cause toxicologic injury. Although several oxygenates can be used in oxy-fuels, this analysis focuses on MTBE because it is the most widely used oxygenate and because the database of relevant toxicologic data is greatest for this oxygenate. The causal assessment is based on an evaluation of the qualitative and quantitative plausibility that oxygenated fuel-related exposures have toxicological effects, and the epidemiologic studies that directly test the hypothesis that the use of oxygenated fuels causes adverse health effects. The plausibility that chemical exposures related to oxy-fuel use cause toxicological effects is very low. This determination is based on consideration of the exposure-response and time-action profiles for relevant toxicological effects of MTBE in animals, experimental MTBE exposure studies in humans, and the possibility that the addition of MTBE to gasoline results in toxicologically significant qualitative and/or quantitative changes in gasoline-related exposures. Similarly, the epidemiologic studies of oxy-fuel exposed cohorts do not support a causal relationship between oxy-fuel use and adverse health effects. Although the data are insufficient to rule the possibility of unique sensitivity in a small segment of the population, the strength of the evidence and the availability of other more plausible explanations for the health complaints reported in association with oxy-fuels support a high degree of confidence in the conclusion that MTBE-containing oxygenated fuels are not the cause of acute toxicity in the general population.  相似文献   
962.
Puerto Rican children are more likely to have asthma than children in any other racial/ethnic group in the United States, yet little research has examined the factors contributing to childhood asthma among Puerto Ricans. Using data from a representative sample of mainland Puerto Rican children, the present study investigates the relationship between preterm birth and early-childhood asthma (i.e., in the first years of life). The roles of other risk factors (i.e., socioeconomic and demographic characteristics, environmental conditions, and maternal health behavior) in the development of asthma in early childhood also are considered. The analysis reveals a relatively high rate of asthma for preterm children as well as differences between term and preterm children in the risk factors for early-childhood asthma. Measures of socioeconomic status and the cleanliness of the home environment are related to asthma for term, but not preterm, children; in contrast, demographic characteristics and maternal health behavior are important risk factors for asthma among preterm children.  相似文献   
963.
Differential life experiences associated with race may critically affect the balance between physical and psychological well-being. This study investigated an age-related and disease-related symptom, restless sleep, among older African American and white members of two sociodemographically matched cohorts, community-dwelling older adults and older adults with chronic renal failure undergoing maintenance dialysis therapy. Sleep behaviors reflect age-dependent and disease-dependent homeostatic and circadian state regulation but are also socioculturally patterned. As hypothesized, restless sleep was significantly more characteristic of the older adults in the chronic disease cohort. With non-renal health conditions, depressed mood, perceived health, medication use, and sociodemographic variables controlled, however, African Americans were significantly less likely than whites in the chronic disease cohort to report restless sleep. African American and white patients differed in their expression of public and private religiousness, which in turn were associated, respectively, with depressed mood and restless sleep complaint. In addition, we suggest that differences for African American and white patients in the environmental exposure of chronic dialysis therapy, including African Americans' greater social integration within the dialysis treatment setting, contributed to their being less at risk than their white peers for subjective perception of sleep decay, a marker of overall well-being.  相似文献   
964.
965.
The purpose of this study was to determine whether a theory-based framework could be used to deductively identify and understand the characteristics of motivational leaders of physical activity groups for older adults. Participants were 23 older adults (mean age = 78.5 +/- 8.0 years, 65% women). An interview-guide approach was employed to elicit older adults' thoughts on important characteristics of physical activity group leaders. The data suggested that effective leaders are those whom the participants feel are properly qualified, are able to develop a personal bond with participants, and can use their knowledge and the group to demonstrate collective accomplishments. It was concluded that the findings could be used to extend the leadership activities beyond the traditional technical performance and individual feedback to include activities of social integration. Furthermore, the conceptual framework identified can serve as a valuable tool in guiding future researchers in their examination of leadership in physical activity groups for older adults.  相似文献   
966.
This study examined the sexual practices and function of midlife women by ethnicity (African American, Caucasian, Chinese, Hispanic, Japanese) and menopausal status. Sexual behavior was compared in 3,262 women in the baseline cohort of SWAN. Participants were 42 to 52 years old, premenopausal or early perimenopausal, and not hysterectomized or using hormones. Analysis used multivariate proportional odds regression. In our sample, 79% had engaged in sex with a partner in the last 6 months, and a third considered sex to be very important. Common reasons for no sex (n = 676) were lack of partner (67%), lack of interest (33%), and fatigue (16%). Compared with Caucasians, Japanese and Chinese women were less likely, and African Americans more likely, to report sex as very important (p < 0.005). Significant ethnic differences were found for frequency of all practices. Perimenopause status was associated only with higher frequencies of masturbation and pain during intercourse.  相似文献   
967.
968.
969.
The complexity of individual work with parents whose children are in treatment because of their difficulties is explicated. An exploratory study of 15 mothers' experiences with such treatment is reported. The focus of the study was on parents' expectations, their relationships with their own and their child's clinician, the process of treatment and termination. The findings are integrated with relevant literature and clinical experience to provide a tandem treatment model in which emphasis is placed on clarifying parents' expectations, working with parents' individual issues as well as their role as parents, and focusing first on their children's problems, then gradually moving to the parents' concerns about their own problems.Ms. Staver is a retired Chief Psychiatric Social Worker, Judge Baker Guidance Center  相似文献   
970.
The non-profit sector has become increasingly important in diverse economic, political and social environments. It is not clear that we have effectively communicated, to colleagues, students and decision makers, theoretical developments useful for understanding and managing non-profit organizations. This paper discusses the potential implications of institutional theory to the management of one type of non-profit organization, the publicly supported non-profit organization with input-output relationships that are not well understood. We review institutional theory and discuss the implications of institutional theory to the management and evaluation of publicly supported non-profit organizations.  相似文献   
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