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In newly diagnosed adult patients with epilepsy followed prospectively on monotherapy, carbamazepine and phenytoin were associated with a fall in plasma uric acid, but sodium valproate and phenobarbitone were associated with a rise in plasma uric acid. The mechanisms and significance of these findings are discussed.  相似文献   
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The potential antidepressant effect of flerobuterol (dl-(fluoro-2 phenyl)-1 t-butylamino-2 ethanol), a new drug related to beta-adrenoceptor agonists, was evaluated and compared with imipramine and salbutamol using classical psychopharmacological tests in mice. Like imipramine and salbutamol, flerobuterol (0.5-32 mg kg-1, ip) fully prevented apomorphine (16 mg kg-1, sc)- and partly reversed reserpine- and oxotremorine-induced hypothermia. At higher doses (16-32 mg kg-1), flerobuterol enhanced the toxic effects of yohimbine. Unlike imipramine, flerobuterol and salbutamol did not reduce immobility duration in the behavioural despair test. Salbutamol and flerobuterol decreased locomotor activity. Flerobuterol did not induce mydriasis, did not prevent oxotremorine-induced tremors or salivary and lacrimal gland secretion and did not reduce reserpine-induced palpebral ptosis. Propranolol (8 mg kg-1, ip) but not alpha-methyl-paratyrosine (75 mg kg-1, ip) prevented the flerobuterol-induced antagonism of apomorphine-induced hypothermia. Our results suggest that flerobuterol demonstrates potential antidepressant activity, which could be related to beta-adrenoceptor activation in mice.  相似文献   
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A number of vitamin D3 metabolites inhibit benzodiazepine- and dimethyl sulfoxide-induced differentiation of Friend erythroleukemia cells. The inhibition is dose dependent and occurs at nM concentrations. The order of potency of these compounds is 1,25-dihydroxycholecalciferol greater than 1,25,26-trihydroxycholecalciferol greater than 1,24R,25-trihydroxycholecalciferol greater than 1 alpha-hydroxycholecalciferol greater than 24R,25-dihydroxycholecalciferol greater than 25S,26-dihydroxycholecalciferol. The inhibition is maximal when the vitamin D3 analogs are added together with the inducer, and becomes progressively decreased with delayed addition. These results suggest that the vitamin D3 metabolites may play a regulatory role in erythropoiesis.  相似文献   
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If proven effective, vaginal microbicides and diaphragms will likely be part of a larger HIV prevention model that includes condoms and other prevention strategies. It is, therefore, important to understand how introducing new prevention methods may affect overall patterns of sexual risk behavior. Data presented were collected as part of a safety and feasibility study of ACIDFORM gel with a diaphragm among 120 women in South Africa. Interviews were administered at enrollment and months 1, 3, 5, and 6 of the trial. Focus groups were conducted at trial exit. Frequency of sex increased significantly after enrollment. This increase appears to be owing to perceived protection from HIV and greater sexual pleasure afforded by the gel. Male condom use was high overall but increased significantly from enrollment. Data suggest this is because of increased partner involvement, increased negotiating power afforded by study participation, and provision of free condoms perceived to be of high quality.  相似文献   
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Obsessive-compulsive disorder is increasingly recognized in patients of different age groups. Serotonergic agents, such as clomipramine, have been recently found to be useful in the management of this condition. However, unexpected side effects, such as dysphoria, aggressiveness, and paranoid ideation, may occur with therapeutic doses of this compound, as evidenced in the cases of two male adolescents presented here. Possible pathogenetic factors, involving serotonin and serotonin-receptor abnormalities are discussed. Management of these side effects is based on adequate dose reduction and monitorization.  相似文献   
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