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991.
An investigation has been made into the effect of 3,4-methylenedioxymethamphetamine (MDMA or ‘Ecstasy’) administration on the concentration of 5-hydroxytryptamine (5-HT), uptake of [3H]5-HT and [3H]paroxetine binding in rat cerebral cortex tissue. Four days after 2 injections of MDMA (20 mg/kg i.p., 6 hr apart) the concentrations of 5-HT and its metabolite 5-HIAA were reduced by 60%. The binding of [3H]paroxetine to the presynaptic 5-HT transporter was decreased and high affinity uptake of [3H]5-HT was reduced by a similar amount, indicating neurodegeneration of 5-HT terminals. Pretreatment with chlormethiazole (100 mg/kg i.p.), 10 min before each MDMA injection prevented the decrease in both [3H]parotextine binding and uptake of [3H]5-HT. The loss in 5-HT and 5-HIAA content was also attenuated. Pretreatment with dizocilpine (1 mg/kg i.p.) or haloperidol (2 mg/kg i.p.) also prevented the MDMA-induced loss of [3H]paroxetine binding and attenuated the loss of 5-HT and 5-HIAA content. All three compounds also decreased the degree of hyperthermia that follows MDMA administration, although previous studies suggest that the long term neurodegeneration is not associated with the acute hyperthermic response. These data support the findings of others that MDMA injection produces degeneration of 5-HT nerve terminals in the cortex, confirm that chlormethiazole, dizocilpine and haloperidol attenuate MDMA-induced neurotoxic loss of 5-HT and demonstrate for the first time that these compounds prevent the neurodegeneration of 5-HT nerve terminals that follows MDMA administration. 相似文献
992.
L. Niskanen H. Enlund V. Jormanainen A. Nissinen M. Uusitupa 《European journal of clinical pharmacology》1994,46(2):101-105
The utilisation of antidiabetic drugs reflects both the prevalence of diabetes and the different therapeutic traditions of physicians. A questionnaire survey to study attitudes to the use of oral antidiabetic drugs amongst physicians and possible changes in treatment habits was carried out in a representative sample of Finnish physicians (n=454) in 1992 and the results were compared with those of a similar survey carried out in 1985, and with drug utilisation statistics.The mean fasting blood glucose level at which a physician would start pharmacological treatment was 8.7 mmol·l–1, which was significantly lower than in the 1985 survey. The responses to various case histories suggested a more active approach to pharmacological treatment compared to the 1985 survey. Insulin treatment especially seems to have gained in popularity. This change in attitude was paralled by an increase in the consumption of antidiabetic drugs in Finland during the observation period. The increase in use of oral drugs was steeper in Finland than in Norway and Sweden.Whether this active approach will improve the metabolic control and prognosis of patients with Type 2 diabetes, remains to be demonstrated. 相似文献
993.
Activity at 5-HT1 and 5-HT2 receptor sites influences sexual behavior in male and female rats. 5-HT3 antagonists reportedly have no effect on copulatory activity in rats of either sex although they influence a variety of other behaviors. The effects of 5-HT3 agonists on sexual behavior are unknown. The following experiments were undertaken to assess the influence of the 5-HT3 agonists 1-phenylbiguanide (PBG) and 2-methyl-serotonin (2-Me-5-HT) on sexual behavior, when administered intracerebroventricularly. Consistent with earlier reports indicating that 5-HT1 and 5-HT2 receptor activity influences reproductive activity in a sex-dependent manner, PBG was found to facilitate male, but not female, rat sexual behavior. 2-Me-5-HT, however, failed to modify either female or male rat sexual activity. Evidence that PBG, but not 2-Me-5-HT, induces carrier-mediated dopamine release suggests that the effect of PBG in male rats is due to dopaminergic mediation. Overall, the present data indicate that 5-HT3 receptor activation has only slight effects on rat sexual behavior. 相似文献
994.
Modafinil is a new drug used in the treatment of narcolepsy. Its administration in mice induced a dose-dependent increase in locomotor activity. The effects of modafinil were compared with those of dexamphetamine on three tests that assessed the anxiety level (drugs were used at doses which induced a roughly similar stimulation of locomotor activity). Dexamphetamine increased the latency of exploration of a white compartment, increased thigmotaxis in an open-field and decreased the time spent in the open arms of an elevated plus-maze. None of these responses was significantly modified by modafinil. We conclude that modafinil does not share the anxiogenic effects of dexamphetamine. 相似文献
995.
Chronic exposure to mild unpredictable stress has previously been found to depress the consumption of a palatable (1%) sucrose solution, and to attenuate food-induced place preference conditioning. In this study the effects of pramipexole (SND-919), a dopamine D2 agonist, were studied during 7–9 weeks of chronic treatment. Pramipexole (1.0 mg/kg per day) reversed the suppression of sucrose intake in stressed animals, increasing sucrose intakes above the levels seen in untreated nonstressed controls. Pramipexole also increased sucrose intake in nonstressed animals; these effects were accompanied by increases in water intake and tended to correlate with weight loss. Drug-treated stressed animals also lost weight, but in this case water intake was unaffected. A second group of animals received a higher dose of pramipexole (2.0 mg/kg per day). The effects of the two doses were very similar. After three weeks of treatment, these animals were switched to a lower dose of pramipexole (0.1 mg/kg per day). Increases in sucrose intake were maintained over three weeks of treatment at the lower dose, with significant recovery of body weight. Two further groups received the same doses of pramipexole (1.0 mg/kg for 6 weeks or 2.0 mg/kg for 3 weeks followed by 0.1 mg/kg thereafter), but received intermittent (twice-weekly) drug treatment. Intermittent pramipexole treatments also tended to increase sucrose intakes, but the results were less consistent from week to week. Following 6–8 weeks of pramipexole treatment, food-induced place preference conditioning was studied in all animals. Untreated stressed animals showed no evidence of place conditioning. Normal conditioning was seen in both groups of stressed animals treated daily with pramipexole (at 1.0 and 0.1 mg/kg) and in the group treated twice weekly at the higher dose (1.0 mg/kg); intermittent treatment at the lower dose (0.1 mg/kg) was ineffective. The results indicate that pramipexole exerts rapid anti-anhedonic effects in the chronic mild stress model. This conclusion is complicated, but not undermined, by drug-induced weight loss and by the presence of significant drug effects in nonstressed control animals. 相似文献
996.
应用国产ELISA试剂盒对157例肝癌、肝硬化病人血清中抗-HCV及HBV-M进行检测,101例肝癌10例抗-HCV阳性,阳性率为9.9%;56例肝硬化6例抗-HCV阳性,阳性率为10.7%;肝癌组抗HCV与HBsAg双阳性率79%(8/101),HBsAg阳性率为723%(73/101),明显高于HCV感染率,说明HBV仍是乙肝流行地区的主要相关因素。14例抗-HCV阳性(包括可疑阳性),肝癌外周血中8例(57.1%)HBsAg阳性,推测HCV可单独作用但更常与HBV形成混合感染参与慢性肝病的癌变过程。 相似文献
997.
流行性出血热若干体液因子和肾脏血液动力学的变化 总被引:2,自引:0,他引:2
对28例流行性出血热(EHF)患者作了体液因子和肾脏血液动力学的观察研究。发现患者从发热期至多尿初期血浆内皮素(ET)、血栓素B2(TXB2)、血管紧张素-Ⅱ(AT-Ⅱ)均高于正常,P物质(SP)则低于正常,6-酮前列腺素F1α(6-k-PGF1α)除极期外其它各期亦见减低,肾小球滤过率(GFR)与肾有效血浆流量(ERPF)从发热后期至多尿期均显著下降,至恢复初期多数重型患者仍未达到正常。上述结果提示体液因子的失衡是造成内脏缺血和急性肾衰的重要因素。 相似文献
998.
Jinyong Lin Wei Sun Enjiang Li Sihui Wang Jingwen Bai Haixian YangTianjin Eye Hospital Tianjin China Tianjin Medical Cellege Tianjin China 《眼科学报》1994,(1)
Eighteen trabeculectomy specimens of congenital glaucoma were examined by light and transimssion electron microscopy. The results showed that the primary anomalies in congenital glaucoma included the developmental defects of trabecular meshwork, excessive collagen fibrils in the trabecular matrix, shifting forward of ciliary muscle fibres and persistent mesenchymal tissues in the anterior-chamber angle. The authors also pointed out the importance of the secondary lesions of the trabecular meshwork in the pathogenesis of congenital glaucoma. Eye Science 1994; 10:50-56. 相似文献
999.
杨兴旺 《眼外伤职业眼病杂志》1994,16(3):202-204
采用综合治疗,抗炎,散瞳,局部治疗与全身应用免疫抑制疗法,治疗319例352眼外伤获得了满意的疗效,眼球挫伤104例,眼球穿孔伤93例,化学烧伤71例,眼炸伤46例。眼热烧伤5例,治疗包括及时清创胶粘或缝合,清除前房出血合理用皮质类固醇和免疫抑制剂等。眼球挫伤治愈率97.12%,穿透伤93.18%,热烧伤66.67%。319例眼外伤治愈率94.67%好转5.33%,并对各种治疗方法进行了讨论。 相似文献
1000.
上海市少年儿童住院医疗保险费用分析 总被引:1,自引:0,他引:1
本文研究了上海市少年儿童住院医疗保险的费用水平、特点和影响因素。研究结果表明:手术与否、患者年龄、就诊地点、家长医疗保健制度和医院等级的差异造成次均费用的差异;次均费用构成比较合理,药品费比例低于全市水平。病种费用居前三位的是白血病、肺炎和先天性心脏病;特殊病种占总医疗服务人次的4.90%,而医疗费用占总费用的32.57%。 相似文献