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Morphine (8–100 mg/kg IP) induces place preference conditioning in mice. The effect of two different periods of isolation (15 and 30 days) was examined. Mice isolated for 15 days but not 30 days exhibited place preference conditioning to morphine (8 mg/kg). After 30 days of isolation morphine could not induce place preference conditioning with the following doses (8, 16, 64, 100 mg/kg). Social regrouping of male mice previously isolated for 30 days with naive female mice for 15 or 30 days resulted in a reappearance of the conditioned place preference to morphine (16 mg/kg). The specificity of this associative deficit was examined by testing learning in isolated compared to non-isolated mice in two distinct settings: escape learning in the Morris water maze and passive avoidance acquisition and retention. On the Morris water maze isolated mice did not differ from non-isolated mice regarding place learning, the probe trial or extinction. Isolated mice were unimpaired in passive avoidance acquisition and retention. It was concluded that the deficits in place preference conditioning were not the result of a global learning impairment in isolated mice. Received: 10 April 1996 /Final version: 20 September 1996  相似文献   
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Studies were conducted to evaluate several cholecalciferol (D3 metabolites: 1,25-dihydroxycholecalciferol [1,25-(OH)2D3], 1,24R,25-trihydroxycholecalciferol [1,24R,25-(OH)3D3], 1 alpha-hydroxy-cholecalciferol (1 alpha-OHD3), 24R,25-dihydroxycholecalciferol [24R,25-(OH)2D3], 1,25-dihydroxy-26,27 hexadeuterium cholecalciferol (1,25-(OH)2-26,27[2H]6D3) and 1,25-dihydroxy-24R-fluorocholecalciferol [1,25-(OH)2-24R-FD3] for their activity in preventing the development of tibial dyschondroplasia in broilers. The basal diet used is low in calcium, high in phosphorus and chlorine and is known to promote a high incidence of tibial dyschondroplasia. The chicks received ultraviolet radiation from fluorescent lights in addition to 1100 ICU/kg (27.5 micrograms/kg) of D3 in the basal diet. Supplementation of the diet with 10 micrograms/kg of all the metabolites except 24R,25-(OH)2D3 significantly lowered the incidence and severity of tibial dyschondroplasia and increased bone ash when compared to birds receiving the basal diet. None of the active D3 metabolites was effective when fed at 0.1 or 1.0 micrograms/kg of diet. Two active compounds tested [1,25-(OH)2D3 and 1,24R,25-(OH)3D3] at 5 micrograms/kg of diet were effective in reducing either the incidence or severity of tibial dyschondroplasia.  相似文献   
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PURPOSE: Gas embolism is a rare but well documented entity during operative hysteroscopy, with an incidence of 10-50%. Catastrophic outcomes occur at a rate of three in 17,000 procedures. The purpose of this report is to present a non-fatal case of gas embolism probably caused by the gaseous products of combustion. CLINICAL FEATURES: A 50-yr-old woman with a history of menorrhagia was scheduled for hysteroscopy and endometrial ablation and polypectomy. Fifteen minutes into the procedure, with the patient in lithotomy position, 20 degree head down tilt, and breathing spontaneously, a sudden oxygen desaturation occurred from 97% to 87%. The patient's end-tidal carbon dioxide dropped from 46 mmHg to 27 mmHg. The patient's breathing pattern remained normal, respiratory rate remained 11-12 breaths x min(-1) but amplitude of the reservoir bag movement was increased. Cardiovascular variables remained stable. She responded rapidly to 100% oxygen and made an uneventful recovery. Having ruled out other possible causes, we concluded gas embolism was responsible for the fall in oxygen saturation and end-tidal CO(2). CONCLUSION: With all the precautions in place to minimize the likelihood of fluid overload and ambient air embolism occurring, we surmised that products of combustion were the cause of the gas embolism. During endometrial ablation, gaseous products of combustion, mainly carbon dioxide, accumulate. The gases may then contribute to the rise in uterine pressure that occurs as irrigation fluid enters the uterus and this rise in pressure in turn encourages passage of gas into the open venous sinuses.  相似文献   
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32nd Annual Meeting of the Scandinavian Society for Psychopharmacology Copenhagen, Denmark April 10–12, 1991 Abstracts  相似文献   
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This paper reports results of an open prospective study of 26 patients who met DSM-III criteria for panic disorder or agoraphobia with panic attacks. Cognitive-behavioral treatment alone produced clinically and statistically significant improvement in panic symptoms, including both full-blown and limited symptom episodes. In addition, the treatment produced improvement in associated symptoms of phobic avoidance and generalized anxiety. This work provides further preliminary indication of the usefulness of cognitive-behavioral strategies as an alternative to medication in symptom-oriented treatments.  相似文献   
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