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The resolution of three 2-substituted derivatives of idazoxan is described. The enantiomers show large separations in activity in a variety of in vitro and in vivo tests, and the active isomers are all potent and selective antagonists at the alpha 2-adrenoreceptor. The significance of these results in relation to those published on the enantiomers of idazoxan and to those on optically active alpha 2-adrenoreceptor agonists is discussed.  相似文献   
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Smoking behavior among participants in the nurses' health study.   总被引:2,自引:1,他引:1       下载免费PDF全文
We analyzed smoking behavior of 91,651 married female nurses, aged 30-55 years in 1976. The prevalence of smoking was similar among all birth cohorts. The largest percentage increase in starting to smoke occurred between ages 15 and 25 years; by age 25, 50 per cent had started smoking. The cessation rate was lowest in earlier birth cohorts and among nurses starting to smoke at earlier ages. The cessation rate increased substantially between 1963-73 compared with the period 1948-58.  相似文献   
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Strahlentherapie und Onkologie - Several randomized trials have demonstrated that men with localized prostate cancer benefit from the use of short-term neoadjuvant androgen deprivation therapy...  相似文献   
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OBJECTIVE: Our purpose was to determine whether the incidence of postoperative endometritis and wound infection is associated with the method of placental removal at the time of cesarean section.STUDY DESIGN: Parturients undergoing cesarean delivery were prospectively randomized to have the placenta removed manually or spontaneously. Patients were excluded from participation if they had received intrapartum prophylactic antibiotics or had been determined to have chorioamnionitis. After delivery of the infant women in the manual group had the placenta extracted by the primary surgeon, whereas women in the spontaneous group had the placenta delivered by gentle traction on the umbilical cord. All study subjects received perioperative prophylactic antibiotics. The primary outcome variable was a postcesarean infection, defined as postcesarean endometritis or wound cellulitis requiring drainage and antibiotic therapy.RESULTS: A total of 333 women were enrolled in the investigation, with 165 assigned to the manual removal group and 168 allocated to have spontaneous removal. There were no statistically significant differences in mean gestational age, frequency or duration of ruptured membranes, frequency or duration of labor, or mean number of vaginal examinations between the two study groups. Postoperative infections occurred in 25 of 168 (15%) women in the spontaneous delivery group compared with 44 of 165 (27%) women in which the placenta was manually extracted (relative risk 0.6, 95% confidence interval 0.4 to 0.9, p = 0.01). Subset analysis of patients delivered with ruptured membranes similarly demonstrated a statistically significant reduction in the incidence of postoperative infections with spontaneous placental removal compared with manual extraction (20% vs. 38%, relative risk 0.5, 95% confidence interval 0.3 to 0.9, p = 0.02). There was a similar trend toward a reduction in postdelivery infections associated with spontaneous placental removal in women with intact membranes; however, this difference did not attain statistical significance.CONCLUSIONS: Spontaneous delivery of the placenta after cesarean delivery is associated with a decrease in the incidence of postcesarean infections. (Am J Obstet Gynecol 1997;176:1250-4.)  相似文献   
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Adult male rats were fed a purified diet containing rice bran or wheat bran with or without a marine fish oil to investigate the possible effects of such dietary combinations on lipid metabolism. Plasma and hepatic triacylglycerols and hepatic lipogenesis were lowered significantly by feeding fish oil with rice bran but not with wheat bran. Plasma cholesterol and hepatic cholesterol synthesis were significantly lower in animals fed fish oil with either bran. Liver microsomal free cholesterol was significantly lower in rats fed rice bran alone than in all other groups. Hepatic low density lipoprotein (LDL) receptor activity was significantly higher in the two groups fed rice bran than in the two groups fed wheat bran. Fish oil significantly decreased hepatic LDL receptor activity and increased hepatic high density lipoprotein (HDL) binding activity with wheat bran but had no significant effects on these parameters when added to the rice bran diet. However, when the data for all groups were pooled, there was a significant negative correlation between hepatic HDL binding activity and LDL receptor activity. Cecal volatile fatty acids were significantly higher in rats fed rice bran, were unaffected by adding fish oil to either bran diet and did not appear to mediate any of the effects of the brans and fish oil on plasma lipids and hepatic lipid metabolism. The combination of rice bran plus fish oil therefore appears to have more beneficial effects on lipid metabolism than wheat bran plus fish oil.  相似文献   
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A review of the stereotactic cases performed at the University of Iowa between February, 1985, and December, 1990, yielded 12 infratentorial stereotactic biopsies in 11 patients. A definitive diagnosis was obtained in 9 of 11 patients. One patient required a second biopsy to obtain a diagnosis and 1 yielded cystic fluid only. The pathological diagnosis obtained included 4 high-grade gliomas, 2 undifferentiated adenocarcinomas, 2 low-grade astrocytomas, 1 malignant ependymoma, 1 pontine hematoma and 1 cyst. None of the patients experienced increased neurological deficit following biopsy and there was no mortality. One patient developed postoperative meningitis. We conclude that stereotactic biopsy of infratentorial lesions can be performed safely with a high probability of obtaining a diagnosis. Adequate tissue diagnosis is necessary to direct further therapy.  相似文献   
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Transient Osteoporosis of the Hip in Pregnancy   总被引:1,自引:0,他引:1  
Summary: Transient osteoporosis of the hip (TOH) is an uncommon condition. This painful regional osteoporosis affects previously healthy women in the third trimester of pregnancy. It is characterized by pain in the affected hip and pronounced osteopenia of the femoral head and neck. It has a relatively short clinical course (average 6 months) and a predictably benign prognosis. Complete clinical and radiological recovery is the rule. The diagnosis is one of exclusion. The cause of the osteopenia is not known, although various aetiological factors have been implicated. A case of TOH occurring in the third trimester of pregnancy with complete recovery within 6 months postpartum is presented.  相似文献   
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