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91.
Exposure to mineral dust was studied among construction workers (N = 437) with the aid of a questionnaire and a chest X-ray examination of the lungs. The results of the questionnaire showed that 81% of the construction workers had been exposed to asbestos. Exposure had occurred in all of the occupational groups studied. Pleural plaques and/or lung fibrosis (ILO greater than or equal to 1/1) were found in 26% of the examined workers; the prevalence varied from 18 to 40% among the various occupational groups. Comparison with a representative sample of the Finnish male population from another investigation indicates that the frequency of lung fibrosis (ILO greater than or equal to 1/1) is at least two times higher among the examined construction workers than among the general population. It seems likely that exposure to asbestos dust can be considered an etiological factor for an appreciable number of the X-ray findings.  相似文献   
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小柴胡汤口服液药效作用的研究   总被引:2,自引:0,他引:2  
杨军  陈澍禾 《中成药》1992,14(6):26-28
观察了小柴胡汤口服液的主要药理作用。研究表明,小柴胡汤口服液有显著抑制角叉菜胶诱发的大鼠踝关节水肿(p<0.05),保护四氯化碳所致的大鼠急性肝功能损害,有极显著降低血清SGPT及LDH的作用(P<0.01)。对家兔发热反应也有较好的抑制作用。此外,小柴胡汤口服液对小鼠兔疫反应也有一定的增强作用,可促进小鼠碳粒廓清速率,提高血清溶血素水平及增强鸡红细胞所致的迟发性过敏反应。  相似文献   
94.
在1989年乌鲁木齐市进行的脐带血筛选中,我室又发现了一例异常胎儿血红蛋白(HbF)。理化性质测定证明该变异体为一轻度不稳定Hb。经反相高效液相色谱法(HPLC)等方法测定证明该变异体为HbF-新疆[~Aγ~T25(B7)Gly→Arg]。胡怀钰曾于1986年首次发现该变异体,并命名。与前例比较,本例除分析方法部分不同外,两例先证者的临床症状亦稍有差别。本例的先证者在半岁前患有轻度贫血,而首例先证者未见关于贫血的报道。  相似文献   
95.
American Society of Transplantation guidelines recommend screening renal transplant recipients for breast, colorectal and prostate cancer. However there is a lack of evidence to support this practice. Computer simulation modeling was used to estimate the years of life lost as a result of these cancers in 50-year-old renal transplant recipients and subjects in the general population. Renal transplant recipients lost fewer years of life to cancer than people in the general population largely because of reduced life expectancy. In nondiabetic transplant recipients, loss of life as a result of these cancers was comparable with that in the general population only under assumptions of increased cancer incidence and cancer-specific mortality risks. Even with two-fold higher cancer incidence and disease-specific mortality risks, diabetic transplant recipients lost considerably fewer life years to cancer than those in the general population. Recommended cancer screening for the general population may not yield the expected benefits in the average renal transplant recipient but the benefits will be considerably higher than for patients on dialysis. Transplanted patients at above-average cancer risk in good health may achieve the benefits of screening that are seen in the general population.  相似文献   
96.
创新药物药动学高通量筛选   总被引:5,自引:0,他引:5  
高通量筛选体系在创新药物药动学筛选中的应用是新药开发研究的一个重要领域。本文回顾了国外创新药物药动学筛选及高通量筛选体系在药动学筛选中的应用,指出药动学的体外高通量筛选在新药开发研究的早期是一种行之有效的方法,不仅可以降低候选化合物的淘汰率,缩短研究开发的周期,降低开发费用,还可以根据筛选的结果对先导化合物结构改造或修饰提出建议,以获得具有良好药动学特性的新候选化合物。  相似文献   
97.
The random dot stereogram E (RDE) has been shown to be a simple and effective test for the detection of binocular abnormalities and defective visual acuity in children. We determined the validity of the RDE as a screening test for reduced visual acuity, amblyopia and strabismus in two separate populations of children.
A nonselective group of 100 school children (aged 5 to 15 years) who presented consecutively to the ophthalmology department at Auckland Public Hospital were tested with the RDE. All cases of amblyopia and strabismus were detected by the RDE. Similar screening with the RDE test of 168 preschool children (aged three to four years) in the community resulted in an unacceptably high over-referral rate. The test was unreliable in the preschool age group because of difficulty in distinguishing between test failure and non-cooperation with the test. The low positive predictive value of the test in the younger age group suggests the test to be unsuitable for preschool vision screening.  相似文献   
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99.
Abstract Colorectal cancer is the second most common cancer killer of Americans. Recently developed and tested methods of screening and surveillance can effectively diagnose and treat the disease in most patients before symptoms develop when the chance of cure is high. It is also possible to prevent colorectal cancer by detecting and resecting premalignant adenomatous polyps. Evidence-based guidelines recommend that the average-risk population greater than age 50 be screened with annual faecal occult blood tests plus periodic flexible sigmoidoscopy. This approach is feasible, efficacious, affordable and cost-effective in a high-risk country such as the US. Widespread compliance with these recommendations could reduce the mortality from this malignancy by more than 50%.  相似文献   
100.
蒙成药经典验方北沙参四味汤历史悠久,有清肺解热、止咳祛痰的功效,临床多用来治疗肺炎、支气管炎等疾病,疗效确切,具有潜在的开发价值。本文基于化学成分、药理作用、质量控制和临床研究,综述了北沙参四味汤的研究现状并预测分析其潜在的药效物质基础,为其后续相关研究提供参考。  相似文献   
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