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991.
N B Ress B J Chou R A Renne J A Dill R A Miller J H Roycroft J R Hailey J K Haseman J R Bucher 《Toxicological sciences》2003,74(2):287-296
Vanadium pentoxide (V2O5) is a slightly soluble compound found in airborne particle emissions from metallurgical works and oil and coal burning. Because the carcinogenic potential of V2O5 was not known, F344/N rats and B6C3F1 mice (N=50/sex/species) were exposed to V2O5 at concentrations of 0, 0.5 (rats only), 1, 2, or 4 (mice only) mg/m3, by whole-body inhalation for 2 years. The survival and body weights of rats were minimally affected by exposure to V2O5. The survival and body weights of male mice exposed to 4 mg/m3 and body weights of all exposed groups of female mice were lower than the controls. Alveolar/bronchiolar (A/B) neoplasms occurred in male rats exposed to 0.5 and 2 mg/m3 at incidences exceeding the National Toxicology Program (NTP) historical control ranges. A marginal increase in A/B neoplasms was also observed in female rats exposed to 0.5 mg/m3. Increases in chronic inflammation, interstitial fibrosis, and alveolar and bronchiolar hyperplasia/metaplasia and squamous metaplasia were observed in exposed male and female rats. A/B neoplasms were significantly increased in all groups of exposed mice. As with rats, increases in chronic inflammation, interstitial fibrosis, and alveolar and bronchiolar epithelial hyperplasia were observed in mice exposed to V2O5. Thus, V2O5 exposure was a pulmonary carcinogen in male rats and male and female mice. The marginal tumor response in the lungs of female rats could not be attributed conclusively to exposure to V2O5. These responses were noted at and slightly above the OSHA permissible occupational exposure limit of 0.5 mg/m3 (dust) (National Institute for Occupational Safety and Health, NIOSH Pocket Guide to Chemical Hazards, U.S. Department of Health and Human Services, Washington, DC, 1997, p. 328). 相似文献
992.
Objective: The purpose of this study is to determine the association between high elevation and hypertensive disorders of pregnancy (HDP).
Methods: Retrospective cohort study using Colorado birth certificate data to compare HDP at high (≥8,000 ft), moderate (4,501–7,999 ft), or low (≤4,500 ft) elevation using logistic regression.
Results: Among the cohort (n = 314,431), 3.4% of women developed a HDP. High or moderate elevation was not significantly associated with HDP relative to low elevation (adjusted odds ratio [aOR] 1.16, 95% confidence interval [CI] 0.93–1.43; aOR 1.14, 95% CI 0.98–1.31, respectively).
Conclusion: Women living at high or moderate elevation do not have higher odds of HDP. 相似文献
993.
Long-term Intake of Dietary Fiber and Decreased Risk of Coronary Heart Disease Among Women 总被引:13,自引:2,他引:11
Wolk Alicja; Manson JoAnn E.; Stampfer Meir J.; Colditz Graham A.; Hu Frank B.; Speizer Frank E.; Hennekens Charles H.; Willett Walter C. 《JAMA》1999,281(21):1998-2004
Context Epidemiological studies of men suggest that dietary fiber intake protects against coronary heart disease (CHD), but data on this association in women are sparse. Objective To examine the association between long-term intake of total dietary fiber as well as fiber from different sources and risk of CHD in women. Design and Setting The Nurses' Health Study, a large, prospective cohort study of US women followed up for 10 years from 1984. Dietary data were collected in 1984, 1986, and 1990, using a validated semiquantitative food frequency questionnaire. Participants A total of 68,782 women aged 37 to 64 years without previously diagnosed angina, myocardial infarction (MI), stroke, cancer, hypercholesterolemia, or diabetes at baseline. Main Outcome Measure Incidence of acute MI or death due to CHD by amount of fiber intake. Results Response rate averaged 80% to 90% during the 10-year follow-up. We documented 591 major CHD events (429 nonfatal MIs and 162 CHD deaths). The age-adjusted relative risk (RR) for major CHD events was 0.53 (95% confidence interval [CI], 0.40-0.69) for women in the highest quintile of total dietary fiber intake (median, 22.9 g/d) compared with women in the lowest quintile (median, 11.5 g/d). After controlling for age, cardiovascular risk factors, dietary factors, and multivitamin supplement use, the RR was 0.77 (95% CI, 0.57-1.04). For a 10-g/d increase in total fiber intake (the difference between the lowest and highest quintiles), the multivariate RR of total CHD events was 0.81 (95% CI, 0.66-0.99). Among different sources of dietary fiber (eg, cereal, vegetables, fruit), only cereal fiber was strongly associated with a reduced risk of CHD (multivariate RR, 0.63; 95% CI, 0.49-0.81 for each 5-g/d increase in cereal fiber). Conclusions Our findings in women support the hypothesis that higher fiber intake, particularly from cereal sources, reduces the risk of CHD. 相似文献
994.
We assessed a telepsychiatry pilot project in which a psychiatric hospital was linked with mental health clinics in five general hospitals. Information was collected through questionnaires administered to patients, service providers and psychiatric consultants, and by interviews. The technology was considered easy to use by participating health-care professionals and patients, and the quality of the sound and picture was adequate. Survey data suggested acceptance and satisfaction on the part of patients, service providers and psychiatric consultants. An economic analysis indicated that at 396 consultations per year the service cost the same as providing a travelling psychiatrist (C$610 per consultation); with more consultations, telepsychiatry was cheaper. Information gathered during the evaluation suggested that the use of videoconferencing for psychiatric consultations was a viable option for an integrated, community-based mental health service. 相似文献
995.
BACKGROUND: The extent of use of antibiotics to treat upper respiratory infections in general practice is an area for concern due to the increasing problem of bacterial resistance. Effective educational strategies to promote rational prescribing are needed. OBJECTIVES: We aimed to examine the effectiveness of prescriber feedback and management guidelines in reducing antibiotics prescribing by GP trainees for undifferentiated upper respiratory tract infection, and in improving the choice of antibiotic for tonsillitis/streptococcal pharyngitis. The research tested a stepwise approach to targeting educational input to high prescribers. METHOD: General Practice trainees in New South Wales (n = 157) were randomly allocated to a treatment group (n = 78) which received an education intervention on antibiotic use, or to a control group (n = 79) which received an intervention on an unrelated topic. Trainees completed three practice activity surveys, each of 110 consecutive patient encounters, with 6-month intervals between surveys. Prescriber feedback and management guidelines on use of antibiotics for URTI and choice of antibiotic for tonsillitis/streptococcal pharyngitis were delivered in a written form between surveys 1 and 2. An educational outreach visit to high prescribers occurred between surveys 2 and 3. Outcome measures were the rate of antibiotic prescribing for all indications, for URTI and prescribing of select antibiotics for tonsillitis/streptococcal pharyngitis. RESULTS: Antibiotic prescribing by the intervention group declined over three occasions from 25.0 to 23.3 to 19.7 per 100 URTI problems, while the control group increased from 22.0 to 25.0 to 31.7 per 100 URTI problems (P = 0.002). Prescribing in agreement with accepted guidelines for tonsillitis/streptococcal pharyngitis increased over time in the intervention group from 55.6 to 69.8 to 73.0 per 100 problems, but decreased in the control group from 59.6 to 57.5 to 58.5 (P = 0.05). CONCLUSION: Prescriber feedback and management guidelines were shown to influence antibiotic prescribing for URTI and choice of antibiotic for tonsillitis/streptococcal pharyngitis. This study provides a model for targeting educational input to those prescribers who most need to change their behaviour. 相似文献
996.
A Bergstr?m T Moradi P Lindblad O Nyrén H O Adami A Wolk 《International journal of cancer. Journal international du cancer》1999,83(2):186-191
The causes of renal cell cancer remain incompletely understood. In one previous retrospective case-control study, high occupational physical activity has been associated with a decreased risk among men, but not among women. Our aim was to investigate the association between occupational physical activity and renal cell cancer in a large cohort in Sweden. A cohort of Swedish men and women was identified in the nationwide censuses in 1960 and 1970, and the reported occupations were classified into 4 levels of physical demands. Follow-up from 1971 through 1989 was accomplished through record linkages to the Swedish Cancer Registry. Multivariate Poisson regression models were used to estimate relative risk (RR) and 95% confidence intervals (CI). We found a monotonic increase in risk of renal cell cancer with decreasing level of occupational physical activity among men (p for trend <0.001). After adjustment for socio-economic status, place of residence, and calendar year of follow-up, men with long-term sedentary jobs had a 25% (RR = 1.25, 95% CI 1.02-1.53) increased risk compared to men with physically demanding occupations. Among women there was no association, the dose-risk trend was not significant (p for trend >0.50). Occupational physical activity was inversely associated with renal cell cancer among men. The absence of association among women might be due to smaller range of exposure, confounding by household work or reproductive factors, or to a difference in biological response to physical activity in men and women. 相似文献
997.
Dairy products, calcium, phosphorous, vitamin D, and risk of prostate cancer (Sweden) 总被引:6,自引:2,他引:4
Chan JM Giovannucci E Andersson SO Yuen J Adami HO Wolk A 《Cancer causes & control : CCC》1998,9(6):559-566
Objectives: Dairy products consistently have been associated with an increased risk of prostate cancer, yet the mechanism of this relationship remains unknown. Recent hypotheses propose that 1,25 dihydroxyvitamin D (1,25 D) is protective for prostate cancer. One study in the United States found that calcium consumption, which can lower circulating 1,25 D, was associated with higher risk of advanced prostate cancer, and we sought to address this hypothesis in a distinct population.Methods: We analyzed data from a population-based case- control study of prostate cancer conducted in Örebro, Sweden, with 526 cases and 536 controls. Using unconditional logistic regression models, we examined the relationship of dairy products, dietary calcium, phosphorous, and vitamin D with risk of total, extraprostatic, and metastatic prostate cancer.Results: Calcium intake was an independent predictor of prostate cancer (relative risk (RR)=1.91, 95 percent confidence interval (CI) 1.23-2.97 for intake 1183 vs. <825mg/day), especially for metastatic tumors (RR=2.64, 95 percent CI 1.24-5.61), controlling for age, family history of prostate cancer, smoking, and total energy and phosphorous intakes. High consumption of dairy products was associated with a 50 percent increased risk of prostate cancer.Conclusions: Our results support the hypothesis that high calcium intake may increase risk of prostate cancer, and this relation may underlie previously observed associations between dairy products and prostate cancer. 相似文献
998.
999.
A comparison of the effectiveness of inpatient and outpatient services for alcohol and drug clients is presented. Controls for program completion and severity of substance use on entry to treatment are included. While inpatients do only as well as outpatients overall, inpatient services show significant advantage for particular classes of clients. Results, though preliminary, suggest that the recent call for a cutback in inpatient services is premature. 相似文献