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Alprazolam, a new benzodiazepine from triazolobenzodiazepine group, produced anxiolytic action in the conflict test with potency similar to that of diazepam. The myorelaxant activity of the drug was relatively weak. Unlike desipramine, alprazolam failed to reduce the immobility of rats in the forced swim test and was unable to prevent clonidine-induced hypothermia. Alprazolam, unlike desipramine, failed also to potentiate behavioral effect of noradrenaline injected into the hippocampus. Alprazolam after acute but not chronic administration antagonized the synchronizing effect of clonidine on EEG pattern. On the other hand, alprazolam similarly to tricyclic antidepressants, prevented the suppression of dominance behavior by clonidine in rats competing for food. The results indicate that alprazolam acts only weakly upon noradrenergic mechanisms related to depression and to antidepressant action of drugs.  相似文献   
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When dealing with patients with periodontal disease of variable severities, dentists must often choose between treating and restoring the involved tooth or indicating its extraction. Different criteria have been adopted in this decision-making process. The purpose of this study was to evaluate the criteria adopted by dentists to indicate the extraction of teeth with periodontitis. Dentists were interviewed at their private practices in three cities of the state of Rio Grande do Sul, Brazil. The evaluated criteria included severity of attachment loss, tooth mobility, furcation involvement, prosthetic planning, periodontal-endodontic lesion, possible systemic involvement due to the presence of periodontitis, referral to a periodontist for evaluation, radiographic bone loss greater than 50%, presence of extensive caries, socio-economic and cultural status of the patient, among others. The most often adopted criteria to indicate the extraction of periodontally affected teeth were the presence of mobility (37.5%), severity of attachment loss (24.3%) and radiographic bone loss greater than 50% (21.2%). The results of the present study demonstrated the difficulties faced by dentists to indicate the extraction of teeth with severe attachment loss, in addition to the establishment of an adequate prognosis. Aspects associated with the past disease were still the most often reported to indicate the extraction of teeth for periodontal reasons.  相似文献   
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Hypertension is a well known risk factor of coronary artery disease. The aim of the study was to evaluate a clinical course and prognosis in hypertensive patients with acute myocardial infarction (MI). 100 consecutive patients with acute MI underwent the study. In 38 of them (28 males and 10 females) a history of hypertension and intermittent rises of arterial blood pressure in a course of MI were stated. All patients underwent 2-DE examination and 24 hours Holter ecg monitoring. Clinical characteristics consisted of the heart failure and arrhythmias occurrence as well as the in-hospital mortality. Significantly higher rate of MI in the past and/or angina pectoris as well as a diabetes mellitus was stated in hypertensive patients. In these patients inferior, transmural MI was more often observed, while there was no difference in life-threatening arrhythmias, pulmonary edema and cardiogenic shock between normotensive and hypertensive patients.  相似文献   
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