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91.
农药唑呀威毒理及中毒治疗的实验研究 总被引:1,自引:1,他引:0
唑呀威(Triazuron)系新型的高效杀蚜虫剂。目前,对其抑制胆碱酯酶活性的毒理尚报道不一。作者在进行毒性测试和发现16名包装工夏季作业时8名出现明显症状的基础上,开展动物实验研究。结果发现,唑呀威有较有机磷农药更为快速的胆碱酯酶抑制作用,大鼠经口染毒112.5mg/kg仅30min内即见全血胆碱酯酶活性显著下降,P<0.01;且存在明显剂量-反应关系。高剂量(200mg/kg)还可引起心血管系统的损害。注射阿托品有显著解救效果,染毒同时给药的解救效果明显优于染毒后5分钟给药,提示愈早给药解救效果愈好。作者由此提出了临床中毒急救措施的建议 相似文献
92.
K. L. Preston K. L. Preston E. C. Strain G. E. Bigelow J. T. Sullivan K. L. Preston 《Psychopharmacology》1996,123(1):15-25
The present study was conducted to determine whether methadone maintenance alters the pharmacodynamic effects of single doses of cocaine. Twenty-two current users of IV cocaine who were not seeking treatment for their illicit cocaine use participated while living on a research unit. Eleven were maintained on methadone 50 mg PO daily as treatment for their opioid abuse; 11 were opioid abusers who were not physically dependent on opioids and who provided opioid-free urines throughout the study. Each subject received acute cocaine challenge doses of 0, 12.5, 25, and 50 mg intravenously in random order under double-blind conditions in separate test sessions. Physiologic and subject-rated responses were measured before injection and for 2 h after. In the methadone maintenance group, cocaine challenge sessions occurred 15.5 h after the daily methadone dose. There were significant differences between the methadone-dependent and nondependent groups: 1) baseline differences related to chronic methadone administration and not associated with cocaine administration (lower respiration rates and pupil diameter; higher skin temperature) and 2) differences in response to cocaine administration; cocaine-induced increases in subject ratings of Drug Effect, Rush, Good Effects, Liking, and Desire for Cocaine and in heart rate were greater in the methadone maintenance patients compared to the non-dependent group. These results indicate that the positive subjective effects and some physiological effects of cocaine are enhanced in methadone-maintained individuals, suggesting a pharmacological basis for the high rates of cocaine abuse among methadone maintenance patients.Some of these data were presented at the annual meeting of the Committee on Problems of drug Dependence, Keystone, Colorado, June 1992 相似文献
93.
The daily fluid intake of male Wistar rats with simultaneous access to 6% ethanol and water was determined during a baseline period (1 week), following adrenalectomy (1 week) and for 3 weeks following SC implantation of hormone pellets containing corticosterone (CORT) or dexamethasone (DEX). Ethanol consumption dropped during the first week of adrenalectomy (ADX) but increased again in the absence of hormone replacement to reach preoperative levels during the ensuing weeks. The CORT treatment, which produced plasma hormone levels similar to the 24-h mean concentration of adrenally intact rats, not only reversed the effect of ADX on alcohol consumption but also enhanced it to levels above those observed in intact rats. Water intake was not affected by the CORT treatment. DEX implants stimulated water intake, but did not enhance the drinking of ethanol. SC injections of RU 28318 (type I corticosterone receptor antagonist; 10 mg/kg) or mifepristone (RU 38486; type II receptor antagonist; 25 mg/kg) at the beginning and halfway through three daily, 6-h tests failed to affect ethanol drinking in adrenally intact rats or in ADX rats bearing CORT implants. Similarly, there was no effect of giving the two antagonists in combination. These results suggest that exogenous CORT can induce excessive alcohol intake in genetically unselected rats and that this facilitatory effect may be mediated by non-genomic cellular mechanisms. 相似文献
94.
Buprenorphine, a partial mu-opioid receptor agonist, has been proposed as a treatment for cocaine abuse. However, studies
in animals have produced conflicting results on the nature of the interaction between buprenorphine and cocaine. In some studies,
buprenorphine attenuated the effects of cocaine and in others it enhanced them. The purpose of the present study was to evaluate
the interaction of buprenorphine and cocaine on the rotational behavior of the nigrally-lesioned rat. Both buprenorphine (0.003–0.1
mg/kg) and cocaine (1.0– 30 mg/kg) alone produced dose-dependent increases in rotational behavior. Buprenorphine produced
long-lasting turning with a peak at 60 min after administration, while cocaine produced turning that peaked immediately after
administration and lasted for about 2 h. To distinguish simple additivity from other possible outcomes, we determined the
relative potency of each drug alone, using a defined level of effect: 150 turns above the saline control in 4 h. This effect
was produced by 10.0 mg/kg cocaine alone and by 0.0175 mg/kg buprenorphine alone. Based on these results, fixed ratio combinations
were tested and the experimentally derived effects were compared to the theoretically additive values, using an isobolographic
analysis. The fixed ratio combinations of the two drugs tested produced turning greater than predicted from simple additivity.
This finding provides statistically-supported evidence for synergism between the actions of buprenorphine and cocaine.
Received: 28 January 1997 / Final version: 7 June 1997 相似文献
95.
对71例肾移植术后患者进行了氨苄青霉素与环孢菌素的相互作用研究。患者在开始服用氨苄青霉素之前、之中、之后的肾功能以及环孢菌素全血浓度测定结果表明,三项指标均无显著改变。另一组肾移植术后患者37例进行的诺氟沙星与环孢菌素相互作用研究,结果与氨苄青霉素的相互作用类似。提示氨苄青霉素、诺氟沙星可安全地与环孢菌素合用,而不影响肾功能。 相似文献
96.
97.
环孢素A体外抗曼氏血吸虫作用的观察 总被引:1,自引:0,他引:1
MF1小鼠实验感染曼氏血吸虫尾蚴1周、3周和6周后,分别经肺静脉和门静脉灌注取虫。实验显示,药物体外抗曼氏血吸虫的作用呈时间、剂量和虫龄依赖方式,童虫和雄虫对药物更敏感。 相似文献
98.
Intravenously injected polystyrene microspheres with functional amino groups (AP-MSs, 0.2,1.0, and 4.0 urn in diameter) were cleared from the blood very rapidly. The calculated half-lives for 0.2-, 1.0-, and 4.0-μm AP-MSs were about 55,60, and 50s; no significant differences were found with 106,107, and 108 microspheres/rat. Loading experiments showed that the liver, spleen, lung, kidney, and heart had a very high capacity to take up AP-MSs. The AP-MSs were distributed mainly to the liver, lung, and spleen, whereas other organs contained less than 1 % of injected AP-MSs. In terms of numbers of AP-MSs per gram of tissue, the highest contents were found in spleen, liver, and lung for 0.2-, 1.0-, and 4.0-um AP-MSs, respectively. There was indication of redistribution of particles from one organ to another during the first 6 h after injection. Chondroitin sulfate A (Chon) and hyaluronic acid (Hya) adsorbed or covalently linked to AP-MSs increased uptake in the liver, with Chon AP-MSs (adsorbed or linked) showing the best effect: about 25% increase compared with unadsorbed 1-μm AP-MSs. Experiments with separated cells in vitro demonstrated that 1 um AP-MSs, intravenously injected, associated only with Kupffer cells. When the microspheres were adsorbed with Chon, there was also association with liver endothelial cells. This finding indicates that conjugation of microspheres with ligands for endothelial receptors may be a useful method for directing microspheres to specific organs, even if the receptors are not by themselves phagocytic 相似文献
99.
100.
[目的]了解泰州市市级各医院的消毒剂使用现状,为指导临床合理、规范使用消毒剂提供依据和指南。[方法]以泰州市5所市级医院为研究对象,全面调查临床使用消毒剂的种类及其使用中消毒剂的有效成份、年消耗量、消毒方法知晓率、染菌量等背景资料。[结果]5所医院使用的消毒剂种类基本相似,主要是含氯消毒剂等高中水平消毒剂,低水平消毒剂使用量很少,消毒剂年消耗量巨大。医院工作人员消毒知识知晓率低,消毒剂使用不合理,影响消毒效果。使用中消毒剂检测合格率为51.4%;其中消毒剂有效成份合格率71.2%;染菌量指标合格率90.9%。消毒剂染菌量合格率与消毒剂配制浓度、消毒时间、消毒方法知晓率之间呈正相关,相关密切程度:消毒时间〉消毒方法〉消毒剂配制浓度;消毒剂总合格率与消毒剂有效成份合格率之间呈正相关。[结论]医院消毒剂使用不合理,可致医院菌株对常用消毒剂产生抗药性。 相似文献