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51.
目的:探讨黑河上蔡段癌症高发区河水及饮用水的致突变性。方法:采集严重污染的黑河河水及沿岸浅井水分别进行以下试验。①用XADⅡ树脂提取各水样中的有机提取物作为待测样品,以呋喃基康酰胺和叠氮钠作阳性对照,以自发回变率为阴性对照,用鼠伤寒沙门氏菌属TA98 、TA100 菌株进行Ames 试验。以突变比MR 值评价试验结果。②松滋青皮蚕豆温浸芽约2 cm ,分别取3 ~4 粒放入不同水样中处理,同时以蒸馏水、郑州市自来水作阴性对照,环磷酰胺(1 mg/L) 作阳性对照进行微核试验。显微镜下观察根尖细胞微核数,统计微核千分率(MCN‰) 。结果:①河水有机提取物对TA98、TA100 菌株均可诱发阳性回变;②沿岸浅井水有机提取物能诱发TA98菌株的阳性回变;③河水、井水均可致蚕豆根尖细胞微核率(MCN‰) 明显增高。④浅井水和河水的致突变性及毒性( 抑菌圈直径大小) 基本相同。结论:①由于浅井水和河水的致突变性及毒性基本相同,故浅井水中的致突变物质可能来源于河水的水平渗透;②沿岸居民癌症高发与河水污染的潜在致癌性有密切关系,应予以高度重视 相似文献
52.
53.
烟溶液与温石棉对细胞增殖活性的影响 总被引:3,自引:0,他引:3
目的 探讨香烟烟雾溶液与温石棉单独及联合作用对细胞增殖活性的影响。方法 将人胚肺( H E L) 成纤维细胞用不同浓度的烟溶液和温石棉单独及联合作用一定时间后,应用[3 H] Td R参入法测定了细胞的增殖能力。结果 低剂量的烟溶液与温石棉单独作用时均可促进细胞的增殖,但较高剂量的烟溶液和温石棉则可抑制细胞的增殖;当二者联合作用时,低剂量的烟溶液与温石棉可协同增加细胞的增殖,而较高剂量的烟溶液与温石棉则只表现为相加作用。结论 烟溶液与温石棉单独及联合作用均可影响 H E L细胞的增殖活性,但其促增殖和抑制增殖能力则随剂量不同而不同。 相似文献
54.
银杏叶提取液对大鼠血脂水平的影响 总被引:20,自引:0,他引:20
银杏树,我国特有,其果、叶应用早在《本草纲目》、《神农本草》就有记载,现代医学表明,从银杏叶中提取分离的黄酮类和萜内酯类等成分治疗冠心病、脑血栓和清除自由基有显著效果[1~3]。本研究按照《保健食品功能学评价程序和检验方法》[4]进行检测,以了解银杏叶提取液对大鼠血脂水平的影响。1 材 料 与 方 法1.1 受试物 银杏叶提取液,为淡棕色液体,仙居县卫生局提供,主要含黄酮成分,其中主要活性成分类黄酮占24%、萜内酯约占6%。1.2 试剂及仪器 胆固醇测定试剂盒、酶法甘油三脂测定试剂盒由宁波市… 相似文献
55.
Preliminary study of electrocautery smoke particles produced in vitro and during laparoscopic procedures 总被引:1,自引:0,他引:1
Background: The objective of this preliminary study was to describe the particles contained in cautery smoke produced during five laparoscopic procedures and verify the collection method during three laboratory experiments on ex vivo animal tissue.
Methods: A cascade impactor collected the smoke according to particle size, and particle weights were calculated on an electronic microbalance. Electron microscopic analysis and energy dispersive X-ray evaluation were used to determine particle morphology and elemental composition.
Results: The particles, distributed according to size on the seven rotating trays of the impactor, had diameters ranging from 0.05 to >25 m, with most being 0.1–1 m. In vitro experiments yielded more particles, especially larger (>5 m) ones, than the surgical procedures, because the cauterized specimens could be placed much closer to the cascade impactor in the laboratory environment, eliminating most obstacles to particle recovery. In the laparoscopic surgery patients, larger particles, because of their physical properties, were more likely to remain trapped in the abdomen or to drop off in the collection apparatus. Uniformly, two populations of particles were demonstrated—either large, irregular fragments (2–25 m) rich in carbon and oxygen, suggesting structural cellular components, or small homogeneous spheres (0.1–0.5 m) composed of sodium, magnesium, calcium, and potassium salts.
Conclusions: This study demonstrates the presence of breathable areosols and cell-size fragments in the cautery smoke produced during laparoscopic procedures. Their exact chemical composition and potential adverse effects for patients and personnel are not known. 相似文献
56.
This article presents findings from a survey of programmes available for tobacco and alcohol users working in 455 of Australia's top 600 companies. Companies were twice as likely to have programmes for smokers (43%) as for problem drinkers (24%) and these programmes were more apparent in large companies. The majority of programmes for smoking were delivered within a health promotion context which included other life-style issues, such as nutrition, exercise, weight management and stress management. Although Employee Assistance Programs (EAPs) were the most commonly available type of work-place programme for excessive drinkers and other drug users, followed by Alcoholics Anonymous and local hospital clinics, only 6% had an EAP for alcohol. Only 21% of programmes for smokers and 12% for excessive alcohol users were evaluated. Around one-quarter of companies knew the costs of smoking programmes, and 9% reported costs of conducting programmes for excessive alcohol consumers. 相似文献
57.
The acute and subchronic effects of hashish extract (20 mg 9-THC/kg) on the social interactions between two drug-treated residents and an untreated intruder male were investigated. In this analysis 28 different behavioral elements were recorded.A single drug application suppressed all categories of behavior, except submissive behavior and flight, in dominant and subordinate residents. Treated animals were less active than controls and immobility was very frequent. An elevated total activity, due to an increase in non-social activities, was observed in the untreated intruder males of this group. Social investigation as well as submissive behavior and flight were reduced in these animals.On introduction of an untreated male after the fourth drug treatment of the residents, the drugged males showed tolerance to the sedative and most of the other behavioral effects of the drug, and intruder males behaved quite normally.The formation of a dominant-subordinate relation within the group was influenced neither by a single nor by repeated drug treatment.The acute and subchronic effects of hashish extract on social, especially aggressive behavior of males are compared to those described in previous papers and the variation in the results of the different studies is discussed. 相似文献
58.
P. Brunel X. Girerd S. Laurent B. Pannier M. Safar 《European journal of clinical pharmacology》1992,42(2):143-146
Summary The aim of the present study was to examine the effect of cigarette smoking in healthy non-smokers on blood pressure and forearm haemodynamics after acute oral administration of non-selective -adrenoceptor blockers with and without intrinsic sympathomimetic activity, viz. pindolol 15 mg and propranolol 80 mg. A preliminary study was done to compare cigarette smoking and sham smoking to evaluate the time-course of the haemodynamic effects of cigarette smoking. The second experiment was then carried out in the same six volunteers, according to a double-blind randomized placebo-controlled crossover design, to evaluate the possible effect of pre-treatment with -adrenoceptor blockers on blood pressure, heart rate and forearm haemodynamics (forearm blood flow, brachial artery diameter and brachio-radial pulse-wave velocity) measured at baseline, during smoking and every five minutes up to 1 h afterwards.No major difference from placebo in blood pressure or forearm haemodynamics was found and pre-treatment with beta-blockers did not prevent the acute vascular effects of cigarette smoking. 相似文献
59.
Rats were trained in a T-shaped maze to discriminate the effects produced by i.p. injections of tetrahydrocannabinol (THC) and the no-drug state (state-dependency, StD). Several doses of both 8-THC (range: 0.75–5.0 mg/kg) and 9-THC (range: 0.75–10.0 mg/kg) were used in order to compare the number of sessions required by the animals until reaching criterion performance. An additional group of rats had to discriminate pentobarbital sodium (20.0 mg/kg) from the no-drug state.Results: THC discrimination was proportional to dose i.e., animals that had to differentiate high doses of THC from no drug acquired the T-maize task faster than animals trained with the lower doses of THC. Acquisition data further suggest that 8-THC is somewhat less potent than the 9-isomer. 9-THC (10.0 mg/kg) produces strong StD, as defined by Overton (1971), since both this group and the barbiturate group reached the criterion within the first 10 training sessions. Time and dose testings suggest that stimulus properties of drugs vary in a quantitative way and that the calculated ED50 values are mainly determined by the training dose used. It was found that the higher the training dose used the higher was the corresponding ED50 value. Hashish smoke can maintain drug responding among THC-trained rats. A lowered content of brain catecholamines and/or serotonin, induced by AMPT (150 mg/kg) and PCPA (310–350 mg/kg), did not lessen 9-THC (2.5 mg/kg) discrimination.Portions of the results were presented at the Fourth Scandinavian Meeting on Physiology and Behavior, Oslo May 22–24, 1975. 相似文献
60.
茵陈提取液对实验性动物肝损伤的作用 总被引:4,自引:0,他引:4
目的 研究茵陈提取液对实验性肝损伤的作用。 方法 用茵陈提取液连续给小鼠灌胃 7d后 ,采用四氯化碳 (CCL4 )腹腔内注射造成小鼠急性肝损伤 ,造型 2 0h后摘除眼球取血 ,测ALT、AST、ALP、TP、G、A等指标 :给大鼠每周二次皮下注射 10 %CCL4油液 0 .5ml/ 10 0g ,造成慢性肝损伤 ,于中毒第三个月初起开始 ,每日用茵陈提取液连续给大鼠灌胃一个月 ,于末次给药 2 4h眶静脉取血 ,分离血清 ,AT、AST、总蛋白、白蛋白、白蛋白 /球蛋白 (A/G)等指示。 结果 CCL4造成小鼠急性肝脏损伤 ,出现明显肝功能异常 ,茵陈提取液治疗组小鼠各项指标较CCL4模型组均有所降低 ,但差异无显著性意义 (P >0 .0 5 ) ;在CCL4所致大鼠慢性肝损伤模型中 ,茵陈提取液治疗组可显著地降低大鼠由CCL4造成的AST活性升高 ,与模型组比较 ,P <0 .0 1。 结论 茵陈提取液对CCL4所致大鼠慢性肝损伤有较好的治疗作用 ,但对CCL4造成小鼠急性肝伤模型没有保护作用。 相似文献