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Twenty-one medically screened insomniacs were studied over 59 nights in a double-blind, parallel groups design study. The 7 patients receiving a short-acting (triazolam) and the 7 receiving a long-acting (flurazepam) benzodiazepine hypnotic showed a similar pattern and magnitude of sleep EEG changes, especially during the latter part of the 37-night treatment period. Both groups significantly increased sleep spindle rate and decreased delta count per minute. The patterns of withdrawal were also similar. Plasma levels of N-desalkylflurazepam were not significantly related to the magnitude of EEG changes.  相似文献   
153.
Mushroom worker's lung disease   总被引:1,自引:0,他引:1  
Stolz  JL; Arger  PH; Benson  JM 《Radiology》1976,119(1):61
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BACKGROUND: Individuals in the carpentry trade, due to lifestyle habits and occupational exposures, may be at above-average risk for colorectal cancer (CRC). Based on the literature which suggests that increasing perceived risk motivates behavior change, we report on the effectiveness of four risk-communication interventions targeted to increase initial, yearly and repeat fecal occult screening (FOBT) among carpenters (N = 860) over a 3-year period. METHODS: Our 2 x 2 factorial design intervention study varied two dimensions of providing CRC risk factor information: (1) type of risk factor-one set of interventions emphasized three basic risk factors (age, family history and polyps); the other set emphasized a comprehensive set of risk factors including basic, lifestyle, and occupational factors, and (2) tailoring/not tailoring risk factor information. Participants were provided FOBTs. Outcomes were the proportion of returned FOBTs. RESULTS: Varying the amount and intensity of delivering CRC risk factors information affected neither risk perceptions nor initial, yearly, or repeat screening. However, yearly and repeat screening rates were greater among participants who received interventions addressing comprehensive set of risk factors, especially with increasing age. CONCLUSIONS: Tailoring on several CRC risk factors appears insufficient to increase and sustain elevated perceptions of CRC risks to promote screening.  相似文献   
156.
The results of Kr-81m/Tc-99m ventilation-perfusion (VP) lung scintigraphy were correlated with the results of pulmonary angiography for 74 patients suspected of having pulmonary embolism (PE). Among patients having a diagnostic scan, the sensitivity and specificity of scintigraphy were 91% and 94%, respectively. Also, 157 consecutive cases of Kr-81m/Tc-99m VP lung scintigraphy were reviewed, and the frequency of an indeterminate scan was found to be 22%. A similar frequency was found for VP scintigraphy with xenon-133. Of eight patients who had indeterminate scans due to the presence of a single VP mismatch, four were demonstrated to have PE by angiography. Kr-81m is an excellent agent for VP scanning in cases of suspected PE, offering accuracy in diagnosis as well as favorable physical properties.  相似文献   
157.
BACKGROUND: Health care workers (HCWs) are at risk of exposures to human blood and body fluids (BBF). Needlestick injuries and splashes place HCWs at risk for numerous blood-borne infections including human immunodeficiency virus (HIV), hepatitis B (HBV), and hepatitis C (HCV). Utilizing a new comprehensive occupational health surveillance system, the objective of this research was to better define the BBF exposure risk and risk factors among employees of a large tertiary medical center. METHODS: A population of 24,425 HCWs employed in jobs with potential BBF exposures was followed for BBF exposure events from 1998 to 2002. BBF exposure rates were calculated for strata defined by age, race, gender, occupation, work location, and duration of employment. Poisson regression was used for detailed analyses of risk factors for BBF exposure. RESULTS: The study population reported 2,730 BBF exposures during the study period, resulting in an overall annual rate of 5.5 events/100 FTEs and a rate of 3.9 for percutaneous exposures. Higher rates were observed for males, persons employed less than 4 years, Hispanic employees, and persons less than 45 years of age. Much higher rates were observed for house staff, nurse anesthetists, inpatient nurses, phlebotomists, and surgical/operating room technicians. Poisson regression results strengthened and extended results from stratified analyses. Rates of percutaneous exposures from hollow needles were found to decrease over the study period; however, exposure rates from suture needles appear to be increasing. CONCLUSION: While continued training efforts need to be directed toward new HCWs, our data also suggest that employees who have been in their job 1-4 years continue to be at higher risk of BBF exposures. This research also points to the need for better safety devices/products and work practices to reduce suture-related injuries.  相似文献   
158.
OBJECTIVE: Crystalline silica may act as an immune adjuvant to increase inflammation and antibody production, and findings of occupational cohort studies suggest that silica exposure may be a risk factor for systemic lupus erythematosus (SLE). We undertook this population-based study to examine the association between occupational silica exposure and SLE in the southeastern US. METHODS: SLE patients (n = 265; diagnosed between January 1, 1995 and July 31, 1999) were recruited from 4 university rheumatology practices and 30 community-based rheumatologists in 60 contiguous counties. Controls (n = 355), frequency-matched to patients by age, sex, and state of residence, were randomly selected from driver's license registries. The mean age of the patients at diagnosis was 39 years; 91% were women and 60% were African American. Detailed occupational and farming histories were collected by in-person interviews. Silica exposure was determined through blinded assessment of job histories by 3 industrial hygienists, and potential medium- or high-level exposures were confirmed through followup telephone interviews. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated by logistic regression. RESULTS: More patients (19%) than controls (8%) had a history of medium- or high-level silica exposure from farming or trades. We observed an association between silica and SLE (medium exposure OR 2.1 [95% CI 1.1-4.0], high exposure OR 4.6 [95% CI 1.4-15.4]) that was seen in separate analyses by sex, race, and at different levels of education. CONCLUSION: These results suggest that crystalline silica exposure may promote the development of SLE in some individuals. Additional research is recommended in other populations, using study designs that minimize potential selection bias and maximize the quality of exposure assessment.  相似文献   
159.
BACKGROUND: Persons in the construction trades in the US have high rates of alcohol and substance abuse. We had the unique opportunity to evaluate health care utilization through private insurance and workers' compensation for a group of carpenters at high risk of injury and substance abuse. METHODS: We identified a cohort of union carpenters. Their claims for medical care through union insurance and workers' compensation, and appropriate measures of time at risk were documented. Using methods of indirect standardization, we compared utilization and costs between carpenters with and without alcohol and substance-abuse related diagnoses (ASRD). RESULTS: Through private insurance, those with ASRD had 10% higher outpatient utilization and 2.1 times higher rates of hospitalizations for injury care; 2.6 times higher rates of outpatient care; and 2.9 times higher inpatient admissions for non-injury care. Individuals with ASRD had only modestly increased rates (10%) of outpatient utilization through workers' compensation. CONCLUSIONS: These findings support the need for alcohol and drug abuse prevention and treatment services for this workforce. Operationalizing this among highly mobile workforces, such as the construction trades, is a challenge. While not intending to minimize the problems of alcohol or substance abuse on the job among carpenters, the focus of prevention should not necessarily be in the workplace.  相似文献   
160.
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