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91.
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids.  相似文献   
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Although care management approaches have potential to improve clinical outcomes and reduce high health care costs of patients with complex substance use disorders, characterized by high psychosocial, psychological, and/or medical needs and high acute health care utilization, little is known about patients' perspectives or experiences with these interventions. The objectives of this study were to identify barriers and facilitators to patient engagement in care management services for complex substance use disorders from patients' perspectives. This pilot study invited 22 men with complex substance use disorders and high health care utilization who were enrolled in a 1-year open trial of a Care Management Model to complete semi-structured interviews at 1- and 3-months post-baseline. Interviews were recorded, transcribed, and analyzed using template analysis. Five themes related to engagement were identified: barriers to conventional substance use disorder treatment, facilitators of care management services, patient–provider relationship, patient-related factors, and enhancements to a Care Management Model. Results highlighted the importance of the patient–provider relationship, individual visits with providers, flexible and personalized treatment, and a focus on recovery over abstinence in promoting patient engagement in care management services. Results also highlighted a need for increased outreach and assistance with housing and transit to treatment. Patients' perspectives support key elements of the care management services that are designed to facilitate patient engagement and suggest the need for additional outreach and assistance with obtaining shelter and transportation. Additional research is needed to evaluate if care management approaches enhance retention, improve outcomes, and reduce health care utilization of patients with complex and chronic substance use disorders.  相似文献   
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The U.S. autopsy rate has fallen precipitously since the 1940s, decreasing from 50 percent of bodies to less than eight percent today. Much of the decrease occurred after 1971 when hospitals were no longer required to do a minimum number of autopsies for accreditation. Since this time, major changes in the health care sector have occurred in the United States, highlighted by the increased importance of managed care. Using data for 46 states from 1987 to 2000, we analyze the degree to which the rise in manage care explains the decrease in the autopsy rate. We find that increases in health maintenance organization market share explain 21 percent of the decrease in the autopsy rate over the years from 1987 to 2000 and reductions in the number of hospital deaths explain another 30 percent. In contrast, we find that increases in the availability of magnetic resonance imaging had no significant effect on autopsy rates when other factors are held constant. Reforming health care financing to restrain the growth in health care costs using incentive mechanisms similar to those employed by managed care organizations has been a recurring policy goal in the United States. Our results imply that these reforms may inadvertently reduce the incentive to monitor medical outcomes using techniques such as autopsies, which is often called the “gold standard” in measuring medical outcomes.  相似文献   
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Nanotechnology has the potential to dramatically improve the effectiveness of a number of existing consumer and industrial products and could have a substantial impact on the development of new products ranging from disease diagnosis and treatment to environmental remediation. The broad range of possible nanotechnology applications could lead to substantive changes in industrial productivity, economic growth, and international trade. A continuing evaluation of the human health implications of exposure to nanoscale materials will be essential before the commercial benefits of these materials can be fully realized. The purpose of this article is to review the human health implications of exposure to nanoscale materials in the context of a toxicological risk evaluation, the current scope of U.S. Federal research on nanoscale materials, and selected toxicological studies associated with nanoscale materials to note emerging research in this area.  相似文献   
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Objective:Using a novel mediation method that presents unbiased results even in the presence of exposure–mediator interactions, this study estimated the extent to which working conditions and health behaviors contribute to educational inequalities in self-rated health in the workforce.Methods:Respondents of the longitudinal Survey of Health, Ageing, and Retirement in Europe (SHARE) in 16 countries were selected, aged 50–64 years, in paid employment at baseline and with information on education and self-rated health (N=15 028). Education, health behaviors [including body mass index (BMI)] and working conditions were measured at baseline and self-rated health at baseline and two-year follow-up. Causal mediation analysis with inverse odds weighting was used to estimate the total effect of education on self-rated health, decomposed into a natural direct effect (NDE) and natural indirect effect (NIE).Results:Lower educated workers were more likely to perceive their health as poor than higher educated workers [relative risk (RR) 1.48, 95% confidence interval (CI) 1.37–1.60]. They were also more likely to have unfavorable working conditions and unhealthy behaviors, except for alcohol consumption. When all working conditions were included, the remaining NDE was RR 1.30 (95% CI 1.15–1.44). When BMI and health behaviors were included, the remaining NDE was RR 1.40 (95% CI 1.27–1.54). Working conditions explained 38% and health behaviors and BMI explained 16% of educational inequalities in health. Including all mediators explained 64% of educational inequalities in self-rated health.Conclusions:Working conditions and health behaviors explain over half of the educational inequalities in self-rated health. To reduce health inequalities, improving working conditions seems to be more important than introducing health promotion programs in the workforce.  相似文献   
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Oxidative stress and neurotoxicity   总被引:1,自引:0,他引:1  
There is increasing awareness of the ubiquitous role of oxidative stress in neurodegenerative disease states. A continuing challenge is to be able to distinguish between oxidative changes that occur early in the disease from those that are secondary manifestations of neuronal degeneration. This perspective highlights the role of oxidative stress in Alzheimer's, Parkinson's, and Huntington's diseases, amyotrophic lateral sclerosis, and multiple sclerosis, neurodegenerative and neuroinflammatory disorders where there is evidence for a primary contribution of oxidative stress in neuronal death, as opposed to other diseases where oxidative stress more likely plays a secondary or by-stander role. We begin with a brief review of the biochemistry of oxidative stress as it relates to mechanisms that lead to cell death, and why the central nervous system is particularly susceptible to such mechanisms. Following a review of oxidative stress involvement in individual disease states, some conclusions are provided as to what further research should hope to accomplish in the field.  相似文献   
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