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Model for the work-relatedness of low-back pain   总被引:2,自引:0,他引:2  
OBJECTIVES: This study aimed at developing a model for determining the work-relatedness of low-back pain for a worker with low-back pain using both a personal exposure profile for well-established risk factors and the probability of low-back pain if the worker were unexposed to these factors. METHODS: After a systematic review of the literature, the pooled prevalence of low-back pain in an unexposed population and the pooled odds ratio (OR) for each risk factor was calculated in a meta-analysis using a random effect model. An unbiased risk estimate for each risk factor was obtained by correcting the pooled OR for confounding by other risk factors. The probability of low-back pain was calculated with a logistic regression model. The input was (i) the age-dependent prevalence when not exposed and (ii) the unbiased risk estimates per risk factor of low and high exposure. The etiologic fraction was calculated to determine the level of work-relatedness. RESULTS: The pooled prevalence for low-back pain among unexposed subjects was 22%, 30%, and 34% for the <35-year, 35-to-45-year, and >45-year age categories, respectively. The pooled OR was 1.51 [95% confidence interval (95% CI) 1.31-1.74] for manual materials handling, 1.68 (95% CI 1.41-2.01) for frequent bending or twisting, 1.39 (95% CI 1.24-1.55) for whole-body vibration, and 1.30 (1.17-1.45) for job dissatisfaction. For high exposure to manual materials handling, frequent bending or twisting, and whole-body vibration, the pooled OR was 1.92, 1.93, and 1.63, respectively. CONCLUSIONS: The model is the first that estimates the probability of work-relatedness for low-back pain for a given worker with low-back pain seen by a general practitioner or an occupational health physician.  相似文献   
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OBJECTIVES: To study changes in health-related quality of life (HR-QL) following acute myocardial infarction (AMI) or congestive heart failure (CHF) in older people (> or = 57 yr). DESIGN: Prospective cohort study. SETTING: Primary healthcare registers. PARTICIPANTS: Patients were enrolled on the basis of primary healthcare records. Eighty-nine AMI patients (mean age = 69.5) and 119 CHF patients (mean age = 74.5) were included for analysis. MEASUREMENTS: HR-QL was conceptualized and measured by means of physical (activities of daily living (ADL), instrumental activities of daily living (IADL)), psychological (depressive symptoms, anxiety), social, and role functioning. Premorbid data (TO) were available from a 1993 community-based survey. Incident AMI and CHF cases, developed after 1993, were prospectively followed for 12 months. Assessments were performed at 6 weeks (T1) and 6 (T2) and 12 months (T3) after diagnosis. RESULTS: At the premorbid assessment, AMI patients did not significantly differ on HR-QL from a reference group of older people, whereas CHF patients were on average older and had worse HR-QL compared to the reference group. Although CHF had not yet been diagnosed at TO, symptoms were already present and resulted in decreased levels of functioning. At T1, all HR-QL measures showed worse functioning compared with TO, except for depressive symptoms that presented later (at T2). In contrast to the delay in depressive symptoms, a significant increase in anxiety was already seen at T1. The effect of the somatic conditions was the largest on physical functioning. Effects on psychological and social functioning were less pronounced but still significant. Effects were maintained during the 12 months of follow-up. CONCLUSION: The negative consequences on HR-QL in both AMI and CHF patients are not temporary. No recovery of function was seen in AMI patients, and functioning of CHF patients continued to decline in the first year after diagnosis.  相似文献   
44.
空心胶囊中残留氯乙醇的测定方法改进   总被引:1,自引:0,他引:1  
目的:改进空心胶囊中残留氯乙醇的测定方法。方法:利用大口径毛细管柱的“溶剂效应”技术,进行测定。结果;色谱图重现性佳,分离效果好。结论;对氯乙醇的测定中,采用大口径毛细管柱分离效果优于固定液为聚乙二醇-1500的填充性。  相似文献   
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OBJECTIVE: To evaluate dynamics in CD8 T cell expansions during highly active antiretroviral therapy (HAART). DESIGN: Various T cell subsets were isolated from blood and lymph nodes and analysed for T cell receptor (TCR) diversity. METHODS: TCR complementarity determining region 3 (CDR3) spectratyping and single-strand conformation polymorphism (SSCP) analyses were performed in combination with sequencing to assess clonality of the subsets. RESULTS: Strongly skewed CDR3 patterns in total CD8 cells and the CD8 subsets CD45RO+CD27+ and CD45RO-CD27+ showed substantial dynamics in dominant CDR3 sizes, resulting in relative improvement of CDR3 size diversity in the first months of therapy. During sustained treatment, TCR diversity changed only moderately. SSCP profiles confirmed oligoclonality of TCR CDR3 perturbations. Various dominant CDR3 sizes for CD4 and CD8 T cells present in lymph nodes, but not in peripheral blood mononuclear cells, before the start of therapy emerged in peripheral blood early during therapy. CONCLUSIONS: HAART induces substantial changes in CD8 TCR diversity, eventually resulting in improvement of the repertoire. Clonal expansions observed in lymph nodes before therapy were observed in peripheral blood after therapy, suggesting that recirculation of CD4 and CD8 T cells from lymph nodes contributes to the early T cell repopulation. Decreased immune activation and possibly naive T cell regeneration subsequently decreased clonal expansions and perturbations in the CD8 TCR repertoire.  相似文献   
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Myelosuppression is a major symptom in the acquired immunodeficiency syndrome (AIDS). Moreover zidovudine, an anti-retroviral drug used to treat AIDS patients has myelosuppressive side effects. Therefore treatment with IL-3, a multi-lineage hemopoietic growth factor may be beneficial for zidovudine-treated individuals. In this study we examined the effect of IL-3 on human immunodeficiency virus (HIV) expression. The proliferative response to rIL-3 and the effects on the replication of the monocytotropic HIV variant, HTLV-III Ba-L, in the absence or presence of the anti-retroviral drug zidovudine was studied in purified human peripheral blood monocytes. Zidovudine concentrations sufficient for complete inhibition of HIV replication did not affect rIL-3 induced monocyte proliferation. Although rIL-3, like rGM-CSF, was able to augment HIV expression in monocytes, it did not interfere with the anti-retroviral activity of zidovudine. These data indicate that rIL-3 is a potential candidate for use in myelosupportive therapy in AIDS patients treated with anti-retroviral drugs.  相似文献   
50.
目的:比较师范院校贫困新生与非贫困新生的心理健康状况。方法:于2005-10在衡阳师范学院完成调查。采用整群抽样横断面调查方法,以衡阳师范学院2005级3089名新生为调查对象,运用症状自评量表对其进行集体测查。在统一指导语下,学生根据最近1周内的自我感觉答题,独立完成,当场收卷。结果数据运用光电阅读机(OMR2000)输入计算机心理测评工具箱标准版V3.0系统进行总分和因子分的统计。量表中没有回答的项目记为"没有",5个以上项目未答者视为问卷无效以及总分低于95分的问卷因缺乏可靠性均不进行分析。所有数据输入电脑后用SPSS11.0软件进行统计分析;群体差异比较用t和Z检验。结果:共发放3089份问卷,收回有效答卷2994份,有效率为96.92%,其中贫困新生有效答卷510份,占17.03%。问卷结果显示,师范院校贫困新生在人际关系、偏执和精神病性3项因子上的得分分别为1.86±0.54,1.70±0.48和1.58±0.43,明显高于非贫困新生(1.78±0.51,1.65±0.46,1.53±0.39,t=3.34,2.02,2.92,P<0.05)。从阳性因子的人数比率来看,师范院校贫困新生在总分阳性的人数比率为0.28,明显低于非贫困新生(0.33,Z=-2.27,P<0.05);而在人际关系、偏执和精神病性3项因子阳性的人数比率分别为0.35,0.30,0.16,明显高于非贫困新生(0.31,0.24,0.13,Z=1.73,2.72,1.71,P<0.05)。结论:师范院校贫困新生的整体心理健康状况并不比非贫困新生差,但是在人际关系敏感、偏执和精神病性3个问题上明显比非贫困新生要严重。  相似文献   
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