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A key feature of occupational health and safety legislation is that it has sought to compartmentalize health and safety issues by creating structures and processes that depart from "typical" social relations of production. The Ontario Labour Relations Board, in adjudicating disputes concerning work refusals, faces the difficult, if not impossible, task of defining and maintaining a sphere in which workers have an uncommon latitude and power. Analysis of cases before the Board during the 1980s shows how it errs on the side of caution and uses criteria related to "typical" social relations of production to define convincing testimony and assess workers' entitlement to redress. Similarly, employers' interests and the requirements of the labor process are a reference point in the Board's definition of the scope of workers' rights and what constitute legitimate penalties for the "abuse" of these. Yet decisions are not wholly biased toward employers; dissenting opinions reveal important differences and progressive rulings establish precedents that could be a basis for future decisions.  相似文献   
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BACKGROUND: Variations in the relationships among income, use of mental health services, and sector of care are examined by comparing data from 3 countries that differ in the organization and financing of mental health services. METHODS: Data come from the 1990-1992 National Comorbidity Survey (n = 5,384), the 1990-1991 Mental Health Supplement to the Ontario Health Survey (n = 6,321), and the 1996 Netherlands Mental Health Survey and Incidence Study (n = 6031). Analysis of the association between income and use of mental health services was carried out for the population that was between ages 18 and 54 years. Differential use of mental health treatment was examined in 3 sectors: the general medical sector, the specialty sector, and the human services sector. RESULTS: No significant association between income and probability of any mental health treatment was observed for persons with psychiatric disorders in any of the 3 countries. However, there were significant differences among countries in the association between income and sector of mental health care treatment. In the United States, income is positively related to treatment being received in the specialty sector and negatively related to treatment being received in the human services sector. In the Netherlands, patients in the middle-income bracket are less likely to receive specialty care, while those in the high-income bracket are less likely to be seen in the human service sector. Income is unrelated to the sector of care for patients in Ontario. CONCLUSIONS: Future research should examine whether differential access to the specialty sector for low-income people in the United States is associated with worse mental health outcomes.  相似文献   
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BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function.  相似文献   
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OBJECTIVE: Our purpose was to describe clinical characteristics in premenopausal women with uterine myomas and to identify factors associated with hysterectomy.STUDY DESIGN: Data were collected by chart abstraction in 421 premenopausal women with myomas and analyzed by univariate and multivariable regression.RESULTS: Over a median follow-up period of 29 months, 86% of women had symptoms associated with myomas and 40% had an increase in uterine size of >2 gestational weeks. By multivariable regression, bleeding symptoms at presentation and previous surgical history of cholecystectomy and adhesiolysis were significantly associated with greater odds of hysterectomy. There was a significant interaction between age and uterine size, so that as age increased, uterine size had a greater impact on the likelihood of hysterectomy.CONCLUSIONS: In this cohort of premenopausal women myomas were associated with symptoms in almost all women over the follow-up period. Hysterectomy was performed in 22% of women overall. (Am J Obstet Gynecol 1997;176:1213-9.)  相似文献   
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General population survey data are used to disaggregate the associations of substance use disorders with suicide attempts in order to evaluate a number of hypotheses about the processes leading to these associations. Data are from the US National Comorbidity Survey (1990-1992). Discrete-time survival analysis is used to study the effects of retrospectively reported temporally prior substance use, abuse, and dependence in predicting first onset of suicidal behavior. Alcohol and drug use predict subsequent suicide attempts after controlling for sociodemographics and comorbid mental disorders. Previous use is not a significant predictor among current nonusers. Abuse and dependence are significant predictors among users for three of the 10 substances considered (alcohol, inhalants, and heroin). The number of substances used is more important than the types of substances used in predicting suicidal behavior. Disaggregation shows that the effects of use are largely on suicidal ideation and nonplanned attempts among ideators. In comparison, the effects of use on suicide plans and planned attempts among ideators are not significant. Clinicians need to be aware that current substance use, even in the absence of abuse or dependence, is a significant risk factor for unplanned suicide attempts among ideators.  相似文献   
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PURPOSE: We quantified the agreement between the underlying cause of death determination from information in hospital medical records and on death certificates, and determined whether the frequency of assigning death from prostate cancer had changed since the introduction of testing for prostate specific antigen. MATERIALS AND METHODS: We retrospectively reviewed and analyzed the information in hospital medical records and on death certificates for men previously diagnosed with prostate cancer who died in 1985 or 1995. RESULTS: The underlying cause of death determinations from a review of 201 hospital medical records agreed with those from information on part 1 of the death certificate in 87% of cases and with those using the International Classification of Diseases-9 system coding rules in 80%. Agreement was higher in men who were older than those who were younger at the time of death, and higher in those diagnosed with prostate cancer several years before death than in those diagnosed shortly before death. CONCLUSIONS: There was a high level of agreement concerning the underlying cause of death after a review of the information in hospital medical records and on death certificates for men with prostate cancer when cause of death was viewed as a dichotomous variable. The International Classification of Diseases-9 coding rules concerning the underlying cause of death favor overreporting rather than underreporting prostate cancer deaths compared with a review of hospital medical records. Cause of death determination does not appear to have changed after the introduction of prostate specific antigen testing.  相似文献   
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Smith  M.  W.  Walters  K.  -A.  Korth  M.  J.  M.G.  Katze.  成虹 《世界核心医学期刊文摘》2006,2(6):36-37
背景与目的:感染丙型肝炎病毒(HCV)的肝移植受体在肝移植术后很快进展为复发性肝炎,其中一些患在术后2年内即进展为肝纤维化。该项研究目的是识别影响肝脏疾病进展的分子机制,并寻求早期肝纤维化可能的基因标志物。方法:作对13例(11例感染和2例非感染)肝移植受体,分别在其移植术后1年之内的0、3个月、6个月和12个月对其肝活检标本进行连续性基因表达分析。将所得数据与临床观察结果进行比较,并与从55例非移植的丙型肝炎感染和非感染的肝脏活检标本获得的基因表达数据库进行比较。结果:识别出一些特殊的基因表达模式。第1种模式是移植受体所特有的,而与其是否存在感染无关,其相应的基因编码应激反应蛋白和涉及凝血的血蛋白,在移植术后移植物的恢复中有差异性表达;第2种模式为HCV感染所特有的,包括编码干扰素介导的抗病毒反应和免疫系统(抗原递呈,细胞毒反应)基因编码元件上调,而这些上调表达在进展为早期纤维化的患体内缺失或被抑制,从而提示患疾病的进展可能是由于肝脏对感染的反应受损所致;最后一种基因表达模式,是4例感染了HCV并进展为早期肝纤维化的患第12个月的肝活检标本所特有的。  相似文献   
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