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51.
Summary The inhibition of serum cholinesterase by 2-isopropoxyphenyl-N-methylcarbamate in the sera of 10 subjects was measuredin vitro at a pH of 7.4 and at 25 C. Using two different methods, spectrophotometric and titrimetric, the same rate constantk
i=0.95·103 M–1 min–1 for the inhibition of cholinesterase was obtained. No individual variations in the rate constantk
i were observed. 相似文献
52.
本文以棉产区和稻产区足月新生儿为研究对象,比较了两地区新生儿脐带血胆碱酯酶活性,并以研究对象家中农药使用情况为环境暴露指标,以新生儿脐带血胆碱酯酶活性为效应指标,分析了两者间的关系。逐步回归结果说明在棉产区使用呋喃丹、敌敌畏与脐带血胆碱酯酶总活性呈负相关关系。经统计学检验两地区脐带血胆碱酯酶活性及农民和非农民新生儿脐带血胆碱酯酶活性均未见显著性差异。本文还提供了农村地区脐带血胆碱酯酶活性的平均水平。 相似文献
53.
Juha I. Nickels 《Pflügers Archiv : European journal of physiology》1971,330(1):45-50
Summary A method is described for localisation of the muscle cell and myoneural junction after in vivo microelectrode registration. The glass microelectrodes were filled with saturated K4Fe(CN)6 and Na2HPO4. After registration, the area surrounding the microelectrode was fixed with acetate buffered (pH 5.6) 5% glutaraldehyde, after which gelatine solution with 0.1 M Pb(NO3)2 was applied to the area. Immediately after this, the anions were driven iontophoretically from the microelectrode with a DC while the microelectrode was simultaneously raised. A sediment formed immediately above the muscle cell, which was coloured brown 1% (NH4)2S. The gelatine muscle cell preparate was set upside down in gelatine. After this had hardened it was possible to prepare the single cell layer or single cell preparate, and finally to stain the myoneural junction involved histochemically for cholinesterase.Grant: Pehr Oscar Klingendahl Foundation 相似文献
54.
D. B. Hoover C. R. Craig B. K. Colasanti 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1977,29(3-4):501-513
Summary In rats with cobalt implanted in the right frontal cerebral cortex, acetylcholine (ACh) levels were depressed in the visually non-necotic, surrounding cortex at 7 and 14 days after surgery in comparison with values for controls treated with glass. At 21 days post-implantation, ACh levels were not different for glass and cobalt treatments.Effects of drugs affecting cholinergic function on electro-corticographic (ECoG) epileptiform activity were determined in rats implanted bilaterally with cobalt. The cholinesterase inhibitors, physostigmine and diisopro-pylfluorophosphate reduced both seizure activity and interictal spiking in these cobalt-treated rats. Hemicholinium-3 (HC-3), given subacutely, initially inhibited seizures, but seizure frequency increased later during treatment. HC-3 did not appear to inhibit interictal spiking. These results suggest an involvement of brain cholinergic system in chronic cobalt experimental epilepsy.Seven days after cobalt implantation, HC-3 was less effective in depleting ACh in cerebral cortex adjacent to the cobalt-lesion than in similar tissue from rats with no cobalt implants. This suggests that the cholinergic neurons adjacent to the implant are not highly active at a time when seizure frequency is maximal.A preliminary report on this work appeared in Fed. Proc. 35, 307, 1976This research was supported by a research grant from the West Virginia University Medical Corporation [2-210-1615 (93)] and General Research Support Grant No 5 801 RR 05433-14 (08) 相似文献
55.
Zusammenfassung Die Lebertoxicität von Nitrostigmin (E 605 forte®) und Obidoxim (Toxogonin®) wurde an 11 Bastardhunden durch regelmä\ige Kontrollen der GPT, GOT, GLDH und SDH im Serum über 1 Monat geprüft. Dabei zeigten nur die mit Nitrostigmin (25 l/kg E 605 forte®) behandelten Tiere einen signifikanten Anstieg sämtlicher geprüfter Permentaktivitäten, während die zusätzlich mit Obidoxim (2×20 mg/kg Toxogonin®) behandelten Tiere keinerlei Fermentanstieg als Ausdruck einer Leberschädigung erkennen lie\en. Die Befunde deuten darauf hin, da\ Nitrostigmin für Hunde einedirekt hepatotoxische Substanz darstellt. 相似文献
56.
To determine the effects of low-dosage organophosphate administration on exercise in a hot environment, malathion (7.5 mg/day, 4 days) was administered IP to rats, and effected a 35% (p less than 0.01) reduction in plasma cholinesterase levels. Treadmill endurance (9.14 m/min, no incline, 35 degrees C ambient) was unaffected when the animals were exercised to hyperthermic exhaustion (Tre approximately 43 degrees C). While rates of heat gain were similar between groups, malathion-treated rats displayed higher Tsk (p less than 0.05) at a number of sampling times during the treadmill run. While creatine phosphokinase levels were unaffected by either cholinesterase inhibition or exercise in the heat, lactate dehydrogenase activities were increased (p less than 0.01) in both groups following hyperthermic exhaustion. Although plasma levels of lactate, potassium, urea nitrogen, and creatinine were all significantly (p less than 0.01) increased as a result of exercise in the heat, these increments were not exacerbated by cholinesterase inhibition. Results generally indicated that at this moderate level cholinesterase inhibition, malathion administration did not adversely affect physiological, physical, or thermoregulatory efficacy. 相似文献
57.
58.
Hladká Anna Krampl Václav 《International archives of occupational and environmental health》1975,36(1):67-73
Summary The effect of S-methylfenitrothion on the activity of cholinesterase (ChE) of erythrocytes and plasma was studied as well as the time of its reactivation in rats after peroral administration of 2/3 to 1/100 of LD50. The degradation of S-methylfenitrothion in the organism of rats was evaluated according to the urinary excretion of its metabolite p-nitro-m-cresol. The S-methyl isomer was found to be a more potent inhibitor of cholinesterase than fenitrothion. A remarkable decrease of activity was found even after the administration of 1/100 of LD50. The reactivation of ChE after the administration of 2/3 LD50. took 6 weeks. The excretion was faster and the excreted amounts of p-nitro-m-cresol were significantly higher than they were after fenitrothion administration. 相似文献
59.
目的探讨血清总胆汁酸(TBA)、胆碱酯酶(CHE)及前白蛋白(PA)在不同类型肝病诊断中的应用。方法检测25例健康对照者和134例不同类型肝病患者的血清TBA、CHE及PAB等指标,并对结果进行分析。结果与对照组相比,除慢性肝炎轻度组外,其他各组血清TBA水平均显著高于正常对照(P<0.01),且以急性肝炎最高;与对照组相比,急性肝炎组、慢性肝炎轻度组和肝癌组的血清CHE水平差异无统计学意义(P>0.05);慢性肝炎中、重度组以及肝硬化组血清CHE水平明显降低(P<0.01);与对照组比较,除急性肝炎和慢性肝炎轻度组,其他各组血清PA水平差异均有统计学意义(P<0.01)。结论 TBA、CHE和PA在不同类型肝病诊断中具有一定的实用价值。 相似文献
60.
骨髓单个核细胞移植对不同Child—Pugh分级肝硬化血清胆碱酯酶的影响 总被引:1,自引:0,他引:1
目的 探讨肝动脉插管自体骨髓单个核细胞移植对不同Child~Pugh分级肝硬化患者血清胆碱酯酶(CHE)的影响。方法201例肝硬化患者,其中131例行自体骨髓单个核细胞移植,70例为对照。骨髓穿刺采集自体骨髓,体外分离纯化骨髓单个核细胞,经肝动脉插管将其移植入肝脏。分别于移植后4、8、12、24周观察血清CHE变化情况,比较不同Child—Pugh分级肝硬化患者CHE改变,并观察患者并发症发生情况。结果移植组患者移植前血清CHE为2387.4U/L,移植后4周、8周、12周和24周分别升至2875.9U/L、3190.6U/L、3216.0U/L和3066.5U/L。患者移植后24周内血清CHE水平较移植前显著升高,而对照组无明显升高,两组比较差异有统计学意义。移植组中,Child—PughA级和B级患者血清CHE改善程度优于C级患者。两组患者24周内主要并发症发生率差异无统计学意义。移植后无严重不良事件发生。结论自体骨髓单个核细胞移植能提高肝硬化患者血清CHE水平,对Child—PughA级和B级患者改善明显。 相似文献