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Activity and side-effects of clodronate (Ostac), an inhibitor of osteoclastic bone resorption, were recorded in an open prospective uncontrolled study on 35 patients with metastatic prostatic cancer. All patients had progressive symptomatic bone metastases despite prior hormone therapy. Clodronate was initially administered i.v. for 8 days with 300 mg/day. This was followed by a daily oral administration of 1600 mg. The analgesic effect was evaluated by using a visual analogue scale and by recording the daily consumption of analgesic drugs. Karnofsky index and routine blood examinations, including PSA, were assessed. Repeated bone scans and radiological evaluations were performed. An improvement in pain was observed in 71% of the patients. The mean duration of improvement was 4 weeks. Average survival time was 12 weeks. There were no side-effects after i.v. administration. Slight gastrointestinal discomfort was observed in 3 patients after oral administration. No effect was observed on the extent or biology of the metastases. Clodronate is an effective drug for palliative treatment of symptomatic bone metastases of prostatic carcinoma. It causes fewer and less pronounced side effects than other palliative drug therapies.  相似文献   
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Malignant lymphoma of the prostate is an unusual entity, and nonHodgkin's lymphoma constitutes most reported cases. We report a well documented case of Hodgkin's lymphoma, initially involving the gastrointestinal tract and spleen, which recurred in the prostate following initial remission with chemotherapy. Treatment with external beam radiotherapy resulted in a rapid complete response that has been sustained for 18 months.  相似文献   
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A number of studies have shown that ultrasound has an advantage over physical examination in the diagnosis of acute appendicitis. Most of these studies were conducted by experts in the field of ultrasonography. In this study the influence of experience on the results of the sonography of actue appendicitis were evaluated. All 203 patients admitted to our unit between December 1990 and December 1992 were examined physically and sonographically by a team of surgeons consisting of one experienced sonographer and six inexperienced surgical trainees. Laparotomy was performed in 136 patients (46%). Appendicitis was demonstrated histologically in 119 cases (39.4%). Initial clinical findings were positive in 87 (28.8%). Sonography was positive in 119 patients (39.4%). The 163 patients not operated on demonstrated other pathology on ultrasound in 60 cases (19.9%). The rate of negative laparotomies amounted to 7.2% in our study. Sensitivity and specificity for the sonographic diagnosis were 92% and 95%, respectively. They were only 81% and 80% for physical examination. Overall accuracy was 92% for sonography. Sensitivity and specificity for the inexperienced surgeons were 87% and 93%, respectively, while the experienced surgeon reached values of 97% and 98%, respectively. The results of both groups are comparable with values in the literature, suggesting that ultrasound evaluation of appendicitis is not a diagnostic tool limited to a few experienced sonographers.  相似文献   
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In the search for more selective A2-receptor agonists and on the basis that appropriate substitution at C2 is known to impart selectivity for A2 receptors, 2-alkynyladenosines 2a-d were resynthesized and evaluated in radioligand binding, adenylate cyclase, and platelet aggregation studies. Binding of [3H]NECA to A2 receptors of rat striatal membranes was inhibited by compounds 2a-d with Ki values ranging from 2.8 to 16.4 nM. 2-Alkynyladenosines also exhibited high-affinity binding at solubilized A2 receptors from human platelet membranes. Competition of 2-alkynyladenosines 2a-d for the antagonist radioligand [3H]DPCPX and for the agonist [3H]CCPA gave Ki values in the nanomolar range, and the compounds showed moderate A2 selectivity. In order to improve this selectivity, the corresponding 2-alkynyl derivatives of adenosine-5'-N-ethyluronamide 8a-d were synthesized and tested. As expected, the 5'-N-ethyluronamide derivatives retained the A2 affinity whereas the A1 affinity was attenuated, resulting in an up to 10-fold increase in A2 selectivity. A similar pattern was observed in adenylate cyclase assays and in platelet aggregation studies. A 30- to 45-fold selectivity for platelet A2 receptors compared to A1 receptors was found for compounds 8a-c in adenylate cyclase studies.  相似文献   
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Optimistic biases in public perceptions of the risk from radon.   总被引:1,自引:1,他引:0       下载免费PDF全文
Survey data were obtained from a random sample of 657 homeowners in New Jersey and also from 141 homeowners who had already monitored their homes for radon. People who had not tested tended to believe that they were less at risk than their neighbors, and they interpreted ambiguous predictors of home radon levels in ways that supported their beliefs of below-average risk. Residents who had already tested their homes were relatively accurate about the probability of health effects. In both groups less than half of those who knew that radon can cause lung cancer were willing to admit that it would be serious if they suffered health effects from this source. The optimistic biases of the public may hamper attempts to encourage home radon monitoring and to promote appropriate mitigation measures in homes with elevated radon concentrations.  相似文献   
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