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101.

Background  

Although illness is an important cause of sick leave, it has also been suggested that non-medical risk factors may influence this association. If such factors impact on the period of decision making, they should be considered as triggers. Yet, there is no empirical support available.  相似文献   
102.

Background  

Little is known about the use of organic food during pregnancy. The aim of this study was to describe characteristics associated with the use of organic food among pregnant women participating in the Norwegian Mother and Child Cohort Study (MoBa).  相似文献   
103.
Aging and noise are the two main causes of hearing loss. To estimate the extent to which hearing loss is due to noise and is therefore preventable, an analysis was undertaken, using U.S. surveillance data, of the prevalence of hearing loss in workers in industries categorised according to the percentages of the workforce exposed to noise levels of 85 dBA or more. It was estimated that 13 per cent of the U.S. workforce was exposed to these noise levels, and that occupational noise exposure accounted for 20 per cent of self-reported hearing loss in the male workforce. Applying the industry-specific exposures to Australia, it is estimated that some 657,000 workers are exposed to noise levels of 85 dBA or more in this country. Australian Bureau of Statistics data indicate that constant noise accounts for 38 per cent of self-reported hearing loss in Australian adult males (although this figure would include hearing loss due to non-occupational noise). Data from both countries indicate that the prevalence of noise-induced hearing loss in females is negligible.  相似文献   
104.
Background: Quite low levels of carbon monoxide (CO) exposure have been shown experimentally to induce myocardial ischaemia in subjects with coronary artery disease. This study examines the actual exposure levels in Australian workplaces under normal operating conditions, to assess whether the resulting carboxy-haemoglobin (COHb) levels are high enough to present a risk of myocardial ischaemia in any workers who may have recognised or unrecognised coronary artery disease.
Methods: A total of 84 workers took part in the study, 60 of whom were working in an environment where a combustion process was taking place indoors and were therefore classified as exposed to CO. Ambient CO levels and end-expiratory CO levels (the latter as a predictor of COHb) were measured two-hourly and the number of cigarettes smoked over an eight-hour shift recorded.
Results: Mean workplace CO levels throughout the shift ranged between three and 12 ppm. Mean COHb ranged between 0.7% and 2.1% in non-smokers and 2.1%-7.6% in smokers, except for a single reading of 12.5% in forklift operations (one smoker). Exposed workers had significantly higher COHb levels than the non-exposed, both for smokers and non-smokers. Smoking also had an important independent effect on COHb.
Conclusion: Under workplace conditions prevailing in industries where combustion processes are occurring indoors, CO exposures are unlikely to be high enough to cause myocardial ischaemia in non-smokers. However in a worker whose COHb is already raised from smoking, an increment from such occupational environments could be sufficient to induce myocardial ischaemia in workers with coronary artery disease.  相似文献   
105.
Occupational determinants for rheumatoid arthritis   总被引:3,自引:0,他引:3  
OBJECTIVES: The aim of the present study was to evaluate possible occupational determinants for rheumatoid arthritis according to lifetime occupational history. METHODS: The cases were identified retrospectively from 1980 to 1995 at the University Hospital in Link?ping, Sweden. The study comprised 422 cases and 859 randomly selected referents. Exposure data were collected through a postal questionnaire. RESULTS: For men, occupations with increased, although nonsignificant, odds ratios (OR) were farmers or farm workers [OR 1.8, 95% confidence interval (95% CI) 1.0-3.5], textile workers (OR 2.0, 95% CI 0.3-16.2), asphalters (OR 14.0, 95% CI 1.2-799.0 without latency requirement), and employees at service stations (OR 2.2, 95% CI 0.5-9.5). Among the women, hairdressers and beauticians (OR 2.7, 95% CI 0.8-8.6) had an increased risk for rheumatoid arthritis, as well as those exposed to hairdressing chemicals (OR 3.0, 95% CI 1.0-9.4) and meat products (OR 2.0, 95% CI 1.0-4.0). CONCLUSIONS: Several of the findings in this study are in accordance with those of previous studies. The increased risks of rheumatoid arthritis for asphalters and employees at service stations are however new associations previously not described in the literature.  相似文献   
106.
Rebeccamycin analogues containing uncommon sugars and substitutions on the imide nitrogen have been synthesized. Their cytotoxicities were tested in colon cancer and leukemia cells. Their ability to target topoisomerase I was examined using the in vivo complex of the topoisomerase bioassay in Hela cells. Compared with aglycon 1, the modified compounds with various sugar moieties showed more potent cytotoxicities and topo I targeting ability. In addition, the rebeccamycin analogues with various uncommon sugars showed distinct cytotoxicities and topo I targeting activities. The activity of compounds with 2-deoxyglucose (8 and 9) > compounds with 2,6-deoxyglucose (5 and 6) > compounds with 2,3,6-deoxyglucose (10). Furthermore, the anticancer activity of compounds correlated with their ability to target endogenous topo I. These results suggest that the sugar moiety, especially the 2-OH and 6-OH group of the sugar, rather than the modifications in imide structure on the indolocarbazole ring, is a key element for its activity.  相似文献   
107.
Carbon nanotubes (CNTs) have specific physico-chemical properties that are useful for the electronics, automotive, and construction industries. Yet, despite their many advantages, there is a current lack of available information on the human health and environmental hazards of CNTs. For this reason, the current study investigated the inhalation toxicity potential of multiwall CNTs (MWCNTs). Eight-week-old rats were divided into four groups (10 rats in each group), the fresh-air control (0mg/m(3)), low-concentration group (0.16mg/m(3)), middle-concentration group (0.34mg/m(3)), and high-concentration group (0.94mg/m(3)), and the whole body was exposed to MWCNTs for 5 days (6h/day). Lung cells were then isolated from five rats in each group on day 0 and 1 month after the 5-day exposure, respectively. The MWCNTs were generated by a newly designed generation system, and the MWCNT concentrations in the exposure chambers monitored in accordance with National Institute for Occupational Safety and Health (NIOSH) 0500 using a membrane filter. The MWCNTs were also sampled for an elemental carbon concentration analysis using a glass filter. The animals exhibited no significant body weight changes, abnormal clinical signs, or mortality during the experiment. A single-cell gel electrophoresis assay (Comet assay) was conducted to determine the DNA damage in lung cells obtained from the right lung. As a result, the Olive tail moments were 23.00±1.76, 30.39±1.96, 22.96±1.26, and 33.98±2.21 for the control, low-, middle-, and high-concentration groups, respectively, on day 0 postexposure. Meanwhile, 1 month postexposure, the Olive tail moments were 25.00±2.71, 28.39±3.55, 22.56±1.36, and 31.97±3.16 for the control, low-, middle-, and high-concentration groups, respectively. Thus, the MWCNTs caused a statistically significant increase in lung DNA damage at high concentration (0.94mg/m(3)) when compared with the negative control group on day 0 and 1 month postexposure.  相似文献   
108.
Back injury is a major factor in the large workers' compensation bills with which insurers and employers are familiar. A common response to this problem is to subject prospective employees to screening, with the objective of denying employment to those considered to be a “compensation risk” on account of a history or findings of back trouble. Screening sometimes includes x-ray examination. The employment of a person with a history of back injury involves two conflicting interests: that of the employee who has chosen the risk of recurrent back injury rather than unemployment; and that of the employer who wishes to minimise compensation costs. Resort to screening programs is an unwarranted medical intrusion into a conflict which is essentially economic. Moreover, the use of radiography adds an unnecessary increment to the average population dose of radiation. An alternative approach is suggested, in which a statutory load limit is imposed for male workers, comparable to that which already applies to female workers.  相似文献   
109.
Prevalence of drug use during pregnancy: a pharmacoepidemiological approach   总被引:2,自引:0,他引:2  
INTRODUCTION: Few Brazilian papers on the use of medication in pregnancy have been found in the indexed medical literature. This paper describes the use of medication during pregnancy among women who gave birth in a teaching maternity hospital in the city of Campinas, Brazil. METHODS: A retrospective study on the pattern of drug use during pregnancy was conducted among 1,000 mothers who were interviewed using a structured questionnaire after delivery, while they were still in hospital. The following parameters were registered: sociodemographic characteristics, obstetric and contraceptive history, data on prenatal care and medications used during pregnancy. Statistical analysis was performed using ANOVA and chi-square test at p = 0.05. RESULTS: Among the interviewed patients, 94.6% had taken at least one medication during pregnancy, and 46.1% had used medication in the first trimester. Of 3,778 medications reported, 88.8% had been prescribed by a doctor. The median of medications taken was 3 (ranging from 0 to 18). The six most used classes of medications were: analgesics, spasmolytics, gynecological antiinfectious agents, antianemics, antacids and systemic antibiotics. The five most used medications were: butyl scopolamine, ferrous sulfate, dipirone, nistatin and multivitamin tablets. Only 27.7% of the patients had been alerted to the risk of taking medication during pregnancy. CONCLUSION: Knowing the profile of medications used during pregnancy may help devising programs to provide information to the patients and continuing education to health care professionals.  相似文献   
110.
The vitamin D3 receptor gene (VDR) contains a TaqI RFLP that is associated with increased VDR mRNA stability, increased serum levels of 1alpha,25-dihydroxyvitamin D3 (1,25-D3), and decreased risk for prostate cancer. Determination of the TaqI genotype, in a group of young women with breast cancer (n = 111; age, <37 years) and a control population (n = 130), revealed no overall association to risk for breast cancer. However, patients without TaqI site (TT genotype) showed a significantly increased risk for lymph node metastasis (relative risk, 1.8, 95% confidence interval, 1.3-2.6). Furthermore, a tendency toward an increased survival was found among estrogen receptor-positive, tamoxifen-treated patients who were homozygous for the TaqI site (P = 0.075). We conclude that polymorphism in the VDR gene may influence tumor progression and tamoxifen treatment response in early-onset breast carcinomas.  相似文献   
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