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D-Cycloserine (DCS) has been reported to affect the central nervous system in man. To investigate whether the compound produces specific behavioural effects, DCS was administered to male mice in a resident-intruder situation and the behaviour of the interacting mice assessed using ethological analysis. Resident mice given DCS (32.0–320.0 mg/kg PO, 60 min before testing) showed dose-dependent increases in social investigation, smaller increases in sexual behaviour and decreased aggressiveness. Defensive and flight behaviour were not affected. Intruder mice showed slight increases in sexual behaviour that were not dose-dependent, and small increases in social investigation. The increases in social investigation induced by DCS (320.0 mg/kg) in resident mice were not reversible with R-HA 966 (32.0 mg/kg IP, 30 min before testing), a blocker of the strychnine-insensitive glycine modulatory site associated with theN-methyl-D-aspartate receptor, but were blocked by the GABA antagonist bicuculline (0.56 mg/kg IP, 5 min before testing). The small DCS-induced increase in sexual behaviour in residents was reversed by R-HA 966. Within the parameters of the resident-intruder situation, DCS exerts socio-sexual behaviour-enhancing effects which are dependent upon the role of the interactant, and which are mediated by an action upon multiple substrates. DCS may be regarded as another example of a sociotropic (approach-promoting) agent.Some of these results have been presented at the 1st International Congress on Hormones, Brain and Neuropsychopharmacology, Rodos, Greece, September 12–17, 1993  相似文献   
3.
We present a case of intermittent cessation of blood flow through stent struts during systole, with normal flow during diastole in the previously stented ostial vein graft. After reviewing the initial procedure, we discovered that the operator had difficulty in positioning the stent. After stent deployment, the ostial stent was malpositioned and was protruding more than 50% into the aorta. During systole, the contrast in the stent struts, which are situated in the aorta, was being washed off by systolic blood flow, while in the diastole, the flow of contrast was normal. This is the first case report of this observation with a brief review.  相似文献   
4.
Patients with the irritable bowel syndrome have significantly more rapid and significantly greater slowing of the pulse rate than do age-, sex-, and stressor-matched controls when their pulse rate is measured at initial outpatient clinic attendance. These findings provide further evidence that altered autonomic function exists in patients with the irritable bowel syndrome.  相似文献   
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A 56-y-old female cardiac transplant patient treated with cyclosporine and prednisone noted the onset of three nontender red nodules on the legs and arms after gardening. Biopsy of all lesions revealed inflammatory cells and hyphal elements in the dermis. The dematiaceous fungus cultured from biopsy tissue was a pycnidial-forming organism of the genus Pleurophoma. The lesions responded to the topical application of miconazole.  相似文献   
7.
Chlordiazepoxide alters intravenous cocaine self-administration in rats   总被引:5,自引:0,他引:5  
This investigation was designed to examine the effects of benzodiazepines on intravenous cocaine self-administration in rats. Pretreatment with low doses of the benzodiazepine receptor agonist, chlordiazepoxide (0.3 to 1.0 mg/kg, IP), resulted in small but nonsignificant increases in drug intake with 0.5 mg/kg cocaine, while higher doses (10 mg/kg, IP) significantly decreased drug intake in all rats tested. The effects of chlordiazepoxide on self-administration were attenuated when the concentration of cocaine was increased to 1.0 mg/kg, suggesting that chlordiazepoxide was opposing rather than augmenting the pharmacological actions of cocaine. Pretreatment with the benzodiazepine receptor antagonist, Ro 15-1788 (1.0 to 10 mg/kg, IP), had no effect on self-administration, suggesting that the reinforcing properties of cocaine do not result from direct interactions with benzodiazepine receptors. The result of this investigation demonstrate that chlordiazepoxide alters intravenous cocaine self-administration in rats. Although additional research will be necessary to confirm these data, the results of this investigation suggest that chlordiazepoxide may decrease the reinforcing efficacy of cocaine through indirect actions on dopaminergic neuronal activity potentially mediated through GABAergic mechanisms via benzodiazepine receptor activation.  相似文献   
8.
髁突形态与覆深度关系的研究   总被引:1,自引:0,他引:1  
目的 探讨髁突形态与不同覆深度的关系。方法 选择正常者、开畸形患者、覆正常的错畸形患者和深覆畸形患者各 5 0人 ,均为 18至 2 6岁成人。应用曲面断层片研究左右两侧的髁突形态 ,分别测量并计算上部髁突高度 /升支高度比 (UCH/RH)和髁突高度 /宽度比 (TCH/CW )。将髁突形态分为四种类型 :直立型 (类A) ,前倾型 (类B) ,后倾型 (类C)和尖型 (类D)。结果 开组的上部髁突高度相对升支高度明显小于其他各组 (P <0 0 0 1)。正常组的髁突形态比较粗壮 ,高度宽度比明显小于其他各组 (P <0 0 0 1)。类A和类B属于正常髁突形态 ,占正常组的 99%。类C和类D属于异常髁突形态 ,且在开组中的比例明显高于正常覆组或深覆组。另外 ,只有开组中显示上部髁突高度两侧不对称 (P <0 0 5 )。结论 开组髁突形态与其他各组相比明显不同。  相似文献   
9.
Nakada  T; Kwee  IL; Griffey  BV; Griffey  RH 《Radiology》1988,168(3):823-825
Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging.  相似文献   
10.
Since 1963, 25 patients have undergone Sever-L'Episcopo transfers for obstetrical birth palsy at the St. Louis Unit of the Shriners Hospital for Crippled Children. A follow-up of 2-6 years was possible with a retrospective review of 16 patients. Substantial improvement in shoulder external rotation as well as subjective functional improvement was obtained by all patients. Three transient and one permanent axillary nerve palsies resulting from this procedure are reported.  相似文献   
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