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91.
To assess the effect of smoking on bone mineral density (BMD) at different life stages, to examine whether the effect of smoking differs between men and women, and to discover whether its effect in women differs according to history of estrogen use, a cohort study was carried out with single cross-section measurement of BMD by single and dual photon absorptiometry. The setting was the Framingham Study, a population-based cohort study with over 40 years prospectively collected data on smoking. Subjects (n=1164) consisted of cohort members participating in the 20th biennial Framingham examination (1988–1989). The measurements included in the study were BMD measured at the hip, spine and radius, smoking history ascertained at all Framingham Study examinations since 1948, and other factors affecting BMD (age, weight, estrogen use, caffeine use, alcohol use and physical activity). Neither current smoking, recent (last 10 years) smoking, nor early adulthood smoking resulted in significantly lower BMD at any skeletal site among women who had not taken estrogen. Among women who had taken estrogen, BMD at most sites was lower among current or recent smokers, although the small numbers of smokers made it difficult to find significant differences at all skeletal sites. Among men, a consistently lower BMD at all skeletal sites was observed for smokers regardless of when in their life they smoked (4–15.3% lower), although the effect of smoking during early adulthood was of a lesser magnitude (4–8% lower). Former male smokers who had quit <10 years ago had lower BMD than men who had quit 10 years ago. In conclusion, in women who had used estrogen, BMD was lower in current or recent smokers than it was in non-smokers. In men, smoking at any stage of life had adverse effects on the skeleton that was independent of weight, alcohol or caffeine use, implying other mechanisms for smoking's effect on bone.  相似文献   
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Forty-nine consecutive patients with "cold" thyroid nodules were studied using early and late visual and semiquantitative measurements of 201Tl uptake in the nodule to differentiate benign from malignant nodules. The visual method compared 201Tl uptake in the nodule to the normal thyroid tissue. The semiquantitative method used a lesion-to-non-lesion (L/N) ratio of the same areas. Both measurements were carried out early (15 min) and late (3 hr) following 201Tl injection. The reproducibility of the method for the early and late measurements was tested for intraobserver and interobserver variability as well as for repeatability coefficients. The visual method resulted in 43% sensitivity and 79% specificity for the detection of malignant nodules. The L/N method showed that an early threshold of 1.55 chosen by receiver characteristic analysis had a sensitivity of 57% and a specificity of 86%, while the late ratio of 0.99 had a sensitivity of 100% and a specificity of 62%. It is concluded that a L/N 201Tl uptake method performed 3 hr following 201Tl injection is superior to a visual scoring method as well as to the early L/N 201Tl uptake in detecting malignant thyroid nodules.  相似文献   
94.
Patients were recruited from the UCLA AIDS Research Center who had previously been referred to psychiatry for participation in an open-label pilot treating patients with major depression with fluoxetine. They chose to participate in group therapy for continuing distress in coping with their HIV-seropositive status, dissolution of their support system, "accepting patienthood," and on being placed on an experimental medical protocol. The group was a closed, twenty-session, homogeneous (for patient characteristics), psychoeducational, supportive, and cognitively oriented psychotherapy group. We found this to be a successful intervention in helping patients manage HIV illness and in providing the coping skills and social support necessary to function at home, work, and in their interaction with their health care providers.  相似文献   
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An open study was carried out in 17 acutely ill, newly admitted, floridly psychotic schizophrenic patients to a city hospital in New York. Penfluridol was given on a daily basis up to doses of 120 mg and patients were rated objectively by means of different psychometric evaluations; vital signs were monitored daily as were side effects.The drug was found to be a rapid acting, well-tolerated, and highly effective antipsychotic agent within the population of patients explored and within the dose range used. It was particularly effective in acutely agitated floridly paranoid schizophrenics; a statistically significant impact was achieved by 7 days and usually within 72 h after initiating treatment. The drug appears unique in that (1) its effects are realized without the untoward and usually trouble-some effects of nonspecific sedation attendant upon the use of many other neuroleptic medications, and (2) even within the relatively high doses used it produces no hypotensive effects. It is concluded that this appears to be a unique antipsychotic agent and a potentially important addition to the treatment armamentarium of both acute and chronic schizophrenic individuals.Dr. Klein was a research fellow who has since returned to the University of Munich, West Germany. Dr. Selzer was also a research fellow who is now in private practice  相似文献   
97.
"On the job" motor vehicle deaths number more than 4,000 annually in the U.S. and comprise nearly one-third of all work-related deaths. Yet the Department of Labor has set no standards relating to on-the-road safety of the millions of workers whose jobs entail large amounts of driving, and Department of Transportation standards affecting occupational safety cover only drivers in interstate commerce. Drivers of some commercial vehicles, such as heavy trucks, are at special risk of injury because trucks have usually been exempted for many years from federal motor vehicle safety standards--such as standards for brakes and seatbelts--designed to prevent crashes or protect occupants in crashes. Observations based on a series of 150 fatal crashes involving tractor trailers illustrate the need for better protection of this large population of high-risk workers. Clarification of responsibility within the various federal agencies and application of available knowledge and technology are essential.  相似文献   
98.
Post-transplantation lymphoproliferative disease (PTLD) is a complication of solid organ transplantation that is typically of B-cell origin and associated with Epstein-Barr virus (EBV). In patients receiving orthotopic liver transplantation (OLT) and treated with cyclosporin A. PTLD typically presents between 6 and 17 months post-transplantation as a systemic illness with involvement of the hepatic graft in a minority of cases. A small number of cases of biopsy-proven PTLD arising in the hepatic graft and limited to the liver and periportal structures have been previously reported. This report describes three additional cases of liver-localized PTLD and reviews similar cases in the literature. The donor/host origin of PTLD may have prognostic significance because the two cases in this report that are of donor origin had different clinical and pathologic features compared with the case of host origin. A rapid PCR-based technique for determining the origin of PTLD is described.  相似文献   
99.
PURPOSE: To assess the efficacy and toxicity of chemotherapy alone in patients older than 60 years with primary CNS lymphoma. PATIENTS AND METHODS: Fifty patients with a median age of 72 years and a median Karnofsky performance score (KPS) of 50 were eligible for this multicenter phase II study. The protocol consisted of high-dose methotrexate (MTX), lomustine, procarbazine, methylprednisolone, and intrathecal chemotherapy with MTX and cytarabine. The patients received one induction cycle; if objective response was achieved, five additional maintenance cycles were administered every 6 weeks. The median follow-up of patients was 3 years. RESULTS: Twenty four patients (48%) achieved an objective response (compete response [CR], 42%; partial response, 6%), with a median duration of CR of 27 months (range, 3 to 47+ months). Overall median survival time was 14.3 months, and 1-year progression-free survival was 40% (95% confidence interval [CI], 26% to 53%). Myelosuppression was the most frequent side effect, with grade 3 to 4 neutropenia in 19% of patients. One patient died during chemotherapy, as a result of pulmonary embolism. Most patients improved or preserved their cognitive functions (47% and 45% of the patients, respectively) and KPS (36% and 52% of the patients, respectively) until relapse, whereas cognitive and KPS decline attributed to delayed treatment neurotoxicity occurred in 8% and 12% patients, respectively. CONCLUSION: In the elderly, this chemotherapy regimen compares favorably with radiotherapy (RT) alone and reduces considerably the risk of delayed neurotoxicity associated with combined chemoradiotherapy. Chemotherapy alone is an appropriate strategy in older patients to delay or avoid RT.  相似文献   
100.
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