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排序方式: 共有523条查询结果,搜索用时 15 毫秒
71.
Effects of cadmium on in vitro and in vivo cholinesterase (ChE) activities of brain and muscle tissues of Oreochromis niloticus fingerlings were evaluated, considering its potential use in biomonitoring tropical water pollution. Results show that in vitro
ChE activities were depressed significantly by millimolar concentration ranges of Cd2+. The IC50 values of Cd2+ on in vitro ChE activity in brain and muscle tissues were 1.56 and 4.31 mM, respectively. Exposure of fish to environmentally
relevant concentrations of Cd2+ (5–30 μg l−l) for 28 days evoked only a transient inhibition (21–34%) of in vivo ChE activities. Prior exposure and co-exposure of fish
to 15 μg l−1 of Cd2+ enhanced the extent of inhibition of ChE levels induced by the organophosphorous insecticide chlorpyrifos. As high concentrations
of cadmium have the potential to depress ChE activities, monitoring of metal levels in water bodies with suspected high levels
of metal inputs is necessary to accurately interpret the fish ChE inhibition data in relation to insecticide contaminations. 相似文献
72.
73.
本文介绍了一个微量全血真、假及总胆硷酯酶快速比色测定的新方法,仅需10ul全血和15分钟反应时间。此法以硫代碘化乙酰胆硷为底质,以奎尼丁硫酸盐做为假性胆硷酯酶抑制剂,用二硫双硝基苯甲酸做为显色剂。由于用新斯的明终止反应,故反应时间很精确。用此法测定408例正常人血液中胆硷酯酶活性,建立了正常值。 相似文献
74.
高氟饮水对小鼠脑功能的影响 总被引:17,自引:2,他引:15
目的 探讨高氟饮水对小鼠脑功能的影响。方法 对饮加氟离子浓度100、50、10mg/L水6个月的小鼠,通过行为毒理学实验(穿梭箱试验)判断其学习和记忆功能,并对其脑组织胆碱酯酶(ChE)活力进行测定。结果 饮高氟水的小鼠学习和记忆能力显著落后于对照组;高氟组小鼠脑组织ChF活力显著高于对照组。结论 高氟饮水对小鼠脑功能有显著的影响,氟对中枢神经系统具有毒性作用。 相似文献
75.
目的探讨血清胆碱酯酶活性对慢性乙型肝炎肝组织病理学分级和分期的预测价值。方法 419例慢性乙型肝炎患者行肝穿活检;采用Roche全自动生化分析仪检测血清胆碱酯酶活性。结果血清胆碱酯酶活性在G1与G2、G2与G3、G3与G4之间均有显著性差异(P=0.000、0.000、0.014),在S0与S1、S1与S2之间无显著性差异(P=0.309、0.370),在S2与S3、S3与S4之间有显著性差异(P=0.000、0.000);基于血清胆碱酯酶活性的判别函数预测G1、G2、G3、G4的正确率分别为55.65%、28.25%、27.83%、66.67%,预测S0、S1、S2、S3、S4的正确率分别为43.33%、6.49%、19.01%、31.11%、71.29%;血清胆碱酯酶活性预测G4和S4的ROC曲线下面积分别为0.868和0.831(P=0.000和0.000),以血清胆碱酯酶活性≤5.235×103u/L和≤5.535×103u/L为标准,其预测G4和S4的灵敏度、特异度、准确度分别为1.000和0.822、0.678和0.758、0.687和0.771。结论血清胆碱酯酶活性对预测慢性乙型肝炎肝组织G4和S4有一定的参考价值。 相似文献
76.
目的:探讨胆固醇、胆固醇酯、胆碱酯酶的水平变化在重症肝炎患者病情变化中的意义。方法:选取2007年4月~2009年2月于我院治疗的53例重症肝炎患者为研究对象,将其设为A组,于治疗前后检测其胆固醇、胆固醇酯、胆碱酯酶水平,同时选取同期的50例健康人为对照组(B组),检测其胆固醇、胆固醇酯、胆碱酯酶水平,后对两组胆固醇、胆固醇酯、胆碱酯酶水平进行比较分析。结果:经比较分析发现,A组治疗前胆固醇、胆固醇酯、胆碱酯酶水平与B组比较。差异有高度统计学意义(P〈0.01);而治疗后两组比较,差异有统计学意义或差异无统计学意义(P〈0.05或P〉0.05)。结论:通过比较发现,重症肝炎患者的胆固醇、胆固醇酯、胆碱酯酶水平与其病情有着重要的关系,其水平变化可为疾病的治疗提供依据,值得临床进一步探讨。 相似文献
77.
Characterization of muscle cholinesterases from two demersal flatfish collected near a municipal wastewater outfall in Southern California 总被引:1,自引:0,他引:1
Rodríguez-Fuentes G Armstrong J Schlenk D 《Ecotoxicology and environmental safety》2008,69(3):466-471
Two cholinesterases (ChE) present in vertebrates, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are distributed in tissues in species-specific patterns. English sole (Pleuronectes vetulus, ES) and Hornyhead turbot (Pleuronichthys verticalis, HT) muscle ChE activities were measured in fish from a location near a municipal wastewater outfall and a far-field reference site off the coast of Southern California. ES muscle ChE correlated with total fish length (r=-0.3271) in fish from two sites. No significant differences were observed between gender or sampling sites. Substrate preference assays showed that both ChEs were found in muscle with BChE representing about 30% of the total ChE activity. Data resulting from the use of selective inhibitors suggested the presence of an atypical BChE. Higher sensitivity to pesticide inhibition was observed in ChEs from smaller fish. In HT muscle, ChE activities presented significant differences between males and females, but no correlation was found with total length. No significant differences were observed between sampling sites. Both ChEs were also present with BChE activity constituting 90% of the total ChE activity. Selective inhibitor results indicated the presence of an atypical ChE. Male ChE was more sensitive to pesticide inhibition. These data indicate that species, size, and gender dependent differences in ChE may contribute to differences in susceptibility to ChE-inhibiting toxicants encountered in the marine environment. 相似文献
78.
79.
Poisoning is one of the most important causes of morbidity and mortality in developing countries like India. Anticholinesterase compounds like organophosphates (OP) and carbamates account for the majority of these poisoning cases because of their easy availability and agricultural use. Carbamates are as popular as OPs as insecticides that often go undiagnosed. A fatal case of carbofuran poisoning is presented where serial cholinesterase estimation played a major role in the diagnosis of the same. The pertinent medical literature on carbofuran poisoning is reviewed. The establishment of poison information center in each state is needed for proper diagnosis and management of poisoning cases. 相似文献
80.
目的了解急性呼吸窘迫综合征(ARDS)患儿急性期血清胆碱酯酶(CHE)、前白蛋白(PA)变化特点及临床意义,探讨CHE及PA变化及对预后的影响。方法51例的ARDS患儿分为未愈,死亡组(16例)与治愈/存活组(35例),设同龄普通肺炎对照组患儿30例,全部于入组当天及患ARDS最重时分别检测血清CHE、血气分析、肝功能其他各项指标,41例同时检测血清PA。结果未愈,死亡组ARDS患儿于入组时及最重时血清CHE及PA均显著低于治愈/存活组(人组时均P〈0.05,最重时均P〈0.01),氧合指数(PaOJFiO:)亦显著较低(均P〈0.05)。与正常儿童比较,两组的血清CHE、PA以及氧合指数均显著较低(均P〈0.01)。结论ARDS患儿急性期存在不同程度的血清CHE、PA及氧合指数降低,血清CHE、PA及氧合指数在一定程度上体现ARDS患儿病情的危重程度,对判断ARDS患儿预后有参考价值。 相似文献