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61.
Larry W. Figgs Mustafa Dosemeci Aaron Blair 《American journal of industrial medicine》1995,27(6):817-835
Death certificates from 23,890 male and female non-Hodgkin's lymphoma (NHL) cases and 119,450 noncancer controls from 24 states for the period 1984-1989 were used to generate hypotheses regarding occupational associations. Cases were frequency matched by age, race, and gender with five controls per case. Odds ratios were calculated for 231 industries and 509 occupations. Significant associations were observed for a variety of white-collar professionals (i.e., real estate agents, secretaries, bookkeepers, teachers, postal employees, business agents, engineers, chemists, and medical professionals) and blue-collar occupations (i.e., firefighters, farm managers, aircraft mechanics, electronic repairers, mining machine operators, and crane and tower operators). © 1995 Wiley-Liss, Inc. 相似文献
62.
William Davies Mohammad Jazayeri Patrick Tchou 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1988,2(3):283-286
Summary Encainide is a type Ic antiarrhythmie agent. During encainide therapy, mild Q-T interval prolongation can be seen, usually associated with prolongation of the Q-R-S interval. The present case report describes an unusual and marked prolongation of the Q-T interval with no Q-R-S interval prolongation in a patient who was treated with encainide for atrioventricular nodal reentrant tachycardia. The drug metabolite profile in this patient's serum indicated an unusual elevation of the 3-methoxy-O-demethyl encainide metabolite, versus O-demethyl encainide. This elevated metabolite level suggests that 3-methoxy-O-demethyl encainide has a significant effect on prolongation of repolarization. An abnormal metabolism of encainide may be the underlying mechanism by which some patients would manifest an unusual prolongation of Q-T interval during encainide therapy. 相似文献
63.
Comparison of regulations on occupational carcinogens in several industrialized countries 总被引:1,自引:0,他引:1
F Carnevale R Montesano C Partensky L Tomatis 《American journal of industrial medicine》1987,12(5):453-473
Regulations controlling the manufacture and use of carcinogens in the industrial setting of various countries are examined. In addition, the occupational exposure limits (OEL) of chemicals known or suspected to be carcinogenic in humans are listed, and criteria for the establishment of OELs are discussed. It is also stressed that control measures should not be confined to a few developed countries, and it is hoped that attracting attention to their unevenness will contribute to the implementation of a more efficient primary prevention of cancer. 相似文献
64.
W L de Kort M A Verschoor A A Wibowo J J van Hemmen 《American journal of industrial medicine》1987,11(2):145-156
A group of workers, occupationally exposed to lead and cadmium compounds (n = 53), was compared to a group of workers not exposed to these metals (n = 52). The average values of systolic, diastolic, and mean blood pressure were found to be higher in the exposed group (p less than 0.05). In contrast with the correlation between CdU and blood pressure, the correlation between PbB and systolic and mean blood pressure remained statistically significant after controlling for age and pulse rate (r = 0.22, p less than 0.05). The prevalence of potential hypertension (defined as systolic blood pressure greater than or equal to 160 mm Hg and/or diastolic blood pressure greater than or equal to 95 mm Hg and/or under treatment for hypertension) was higher in the exposed group, but the observed relative risk was not statistically significant: relative risk = 1.91 (95% confidence limits, 0.90-4.05). Furthermore, a significant correlation between PbB and Hgb (r = -0.28, p = 0.004) was observed. Differences in kidney function, as assessed in this study, were not detected. 相似文献
65.
S J Liu Q S Qu X P Xu Y T Liu S N Yin Y Takeuchi T Watanabe O Inoue M Yoshida M Ikeda 《American journal of industrial medicine》1992,22(3):313-323
A factory survey was conducted in three provinces in China from 1985 to 1989. The time-weighted average toluene concentrations in breathing zone air were monitored by diffusive sampling, whereas hippuric acid (HA) concentrations in shift-end urine samples were measured by high performance liquid chromatography (HPLC). Exposed workers (456 men and women) were those for whom toluene (up to 548 ppm toluene) accounted for greater than or equal to 90% of total exposure (by vapor concentration in ppm), whereas 517 nonexposed controls were recruited from the same factories or from factories of the same region. There was a linear correlation between the intensity of toluene exposure and HA concentration in the shift-end urine. Comparison of the results with findings in the literature shows that the toluene-induced increase in urinary HA concentration among workers in China is significantly smaller than the published values, whereas HA concentrations in urine samples from nonexposed controls are comparable to the levels previously reported. 相似文献
66.
口腔医务人员职业暴露防护的研究 总被引:30,自引:2,他引:28
目的探讨口腔医务人员职业暴露防护的危险因素及对策。方法执行标准化、制度化、科学化及普遍预防的管理体系。结果制定了切实可行的口腔医务人员职业暴露防护的管理方案和措施,使口腔医务人员掌握口腔感染管理标准,明确口腔器械消毒程序,在口腔诊治过程中通过实施普遍预防的策略。结论构建口腔医务人员职业暴露防护的措施与方案,可以最大限度地防止口腔医院感染的发生。 相似文献
67.
Sanja Kezic J. B. Nielsen 《International archives of occupational and environmental health》2009,82(6):677-688
Skin is an important route of entry for many chemicals in the work place. To assess systemic uptake of a chemical in contact
with the skin, quantitative information on dermal absorption rates of chemicals is needed. Absorption rates are mainly obtained
from studies performed with intact, healthy skin. At the work place, however, a compromised skin barrier, although not necessarily
visible is common, e.g. due to physical and chemical damage. As reviewed in this article, there are several lines of evidence
that reduced integrity of the skin barrier may increase dermal absorption of chemicals in the occupational setting. An impaired
skin barrier might lead not only to enhanced absorption of a specific chemical, but also to entrance of larger molecules such
as proteins and nanoparticles which normally are not able to penetrate intact skin. In addition to environmental influences,
there is increasing evidence that some individuals have an intrinsically affected skin barrier which will facilitate entrance
of chemicals into and through the skin making these persons more susceptible for local as well for systemic toxicity. This
review addresses mechanisms of barrier alteration caused by the most common skin-damaging factors in the occupational settings
and the consequences for dermal absorption of chemicals. Furthermore, this review emphasizes the importance of maintained
barrier properties of the skin. 相似文献
68.
CR与屏-胶系统摄影在乳腺疾病诊断中的价值 总被引:1,自引:1,他引:0
目的评价X线计算机成像技术在乳腺摄影中的应用价值。方法抽取乳腺CR片和屏-胶乳腺片各500例,由1位副教授和2位主管技师,对摄影条件、照片影像质量及照片影像显示进行对比。结果①CR系统照片影像质量明显高于屏-胶系统;②摄影条件CR数字摄影比屏-胶系统摄影电压高2~3kV,曝光量高35%左右;③照片的X线征象显示率明显高于屏-胶系统。结论CR摄影提高了照片影像质量,为临床提供可靠诊断依据。缺点是曝光条件比屏-胶系统高,相对增加了患者的X线辐射剂量。 相似文献
69.
Werner Adrian 《Clinical & experimental optometry》2003,86(3):179-182
Background: Field studies of the duration of fixation during daytime driving find that it is about 0.2 seconds on average. Thus, the time available to read traffic signs is often limited. There are other circumstances where time to read alphanumeric messages is limited. Data relating time of observation are needed for purposes of ergonomic design as the data available in the literature are limited and uncertain. Method: Visual acuity was measured using Landolt rings in negative contrast, which were presented on a computer screen with a background luminance of 32 cd/m2 for durations that varied between two and 0.02 seconds at three different contrasts. Resulte: Visual acuity depends on the log of the light dose reduced by a factor that may be related to absorption of the light by the eye media. For young observers, it was found that: VA = 0.57 (log C t) + 1.705, where C is the contrast and is expressed as δL/L, where δL is the difference between target and background luminances in cd/m2 and t is the observation time in seconds. Conclusion: This formula or the functions fitted to the data obtained can be used to calculate the increase in target size needed to allow for short observation times. 相似文献
70.
This paper considers the immediate post‐traumatic reactions of rescue personnel who were exposed to the Hilton Hotel bombing in Sinai. The entire rescue personnel (n = 26) were assessed and separated into two groups on the basis of previous exposure to the same type of trauma. The results suggest that among rescue personnel, those with previous exposure had a lower level of post‐traumatic symptoms than those who were being exposed for the first time. This supports the hypothesis that previous exposure to the same type of trauma has an immunizing effect for subsequent same type of traumatic event among rescue personnel. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献