Comparative metabolism of six ethoxychlor analogs and DDT in DDT-resistant and susceptible strains of the house fly Musca domestica L     

Mohammed Y.H. Farroqui  Robert L. Metcalf 《Pesticide biochemistry and physiology》1983,19(2):210-220

The metabolic fate of six ³H-ring-substituted ethoxychlor analogs with altered aliphatic moieties and [¹⁴C]p,p′-DDT was investigated in susceptible and DDT-resistant strains of the house fly Musca domestica Linnaeus. The chloroalkane analogs, dichloroethane, chloropropane, and dichloropropane were primarily metabolized to the corresponding dehydrochlorinated products. This pathway was relatively more prominent in the resistant strain than in the susceptible strain. Biotransformation and detoxication of the isobutane, nitropropane, and neopentane derivatives was through microsomal oxidation (O-deethylation) of aryl ethoxy degradophores, and oxidation of the aliphatic moieties to produce the corresponding benzophenones, with no substantial differences between the resistant and susceptible strain. There was a strong correlation between the Taft ($\text{σ}{}^1$) values for the altered aliphatic moieties of chloroalkane analogs and their rate of dehydrochlorination in both the strains. These results suggest the importance of altered aliphatic moieties in developing resistance-proof DDT derivatives.  相似文献   

In vitro metabolism and interaction of profenofos by human, mouse and rat liver preparations     

Khaled Abass  Petri Reponen  Jorma Jalonen 《Pesticide biochemistry and physiology》2007,87(3):238-247

Biotransformations of profenofos were studied in vitro. Two metabolites, desthiopropylprofenofos and hydroxyprofenofos, were detected by LC-MS after incubation of profenofos with human liver homogenates and different mammalian liver microsomes. The rank order of desthiopropylprofenofos formation in liver microsomes based on intrinsic clearance (V_max/K_m) was mouse > human > rat, while for profenofos hydroxylation it was mouse > rat > human. In view of the ratio between desthiopropylation and hydroxylation intrinsic clearance rates, human liver microsomes were most active in profenofos bioactivation. The interspecies differences and interindividual variation were within range of the default uncertainty/safety factors for chemical risk assessment. CYP3A4, CYP2B6 and CYP2C19 were identified as profenofos-oxidizing enzymes in human liver on the basis of recombinant expressed enzymes and correlation with CYP model activities. The rank order of CYPs in profenofos activation was CYP3A4 > CYP2B6 > CYP2C19, whereas it was the contrary for profenofos hydroxylation. Profenofos inhibited relatively potently several human liver microsomal activities: the lowest IC₅₀ values were about 3 μM for CYP1A1/2 and CYP2B-associated activities. Profenofos is extensively metabolized by liver microsomal CYP enzymes and its interaction potential with several CYP activities is considerable.  相似文献   

兽用阿维菌素类药物剂型研究进展   总被引：9，自引：1，他引：9  

张庆茹 《中国兽医寄生虫病》2004,12(1):41-43

阿维菌素类药物是目前最优良的一类广谱高效兽用抗寄生虫药物。本文就该类药物的不同剂型及其在兽医临床上的应用和毒理学等方面的研究进展进行了综述  相似文献   

兽用抗生素胁迫对水芹生长及其抗生素积累的影响   总被引：4，自引：0，他引：4  

鲍陈燕  顾国平  章明奎 《土壤通报》2016,(1):164-172

土壤和水体环境中抗生素的积累与污染已呈现增加趋势,为了解水体与土壤抗生素污染对植物生长与吸收抗生素的影响及二种介质上植物生长对抗生素污染响应的差异,以水芹为研究植物,分别设计了土培与水培试验,研究了土壤与培养液中不同浓度抗生素(土霉素、恩诺沙星)污染对水芹生长、根系活力、叶绿素含量、过氧化氢酶活性和地上部氮、磷、钾养分积累以及抗生素在水芹各器官中积累迁移的影响。土培试验和水培试验中2种抗生素浓度范围分别为0~10.00 mg kg~(-1)和0~2000μg L-1。结果表明,相同污染水平下,水培试验中抗生素对水芹生长及生理指标的影响明显大于土培试验;抗生素污染对水芹地下部分生长的影响明显大于对地上部分的影响。水培条件下低浓度(50~100μg L-1)的抗生素污染可促进水芹根系的生长,增强根系活力;但土培试验中的这种效应并不明显。总体上,抗生素在水芹中的积累一般是:恩诺沙星土霉素;抗生素在水芹各器官中的积累顺序:根叶、茎。水培试验条件下抗生素在水芹根系中的富集明显高于土培条件下。土霉素对水芹生长的抑制作用大于恩诺沙星。水培条件下高浓度的土霉素和恩诺沙星可促进水芹地上部氮、磷、钾的积累。研究认为,水体抗生素污染对植物生长影响的风险比土壤污染更为明显。  相似文献   

大豆胰蛋白酶抑制剂的研究进展   总被引：2，自引：0，他引：2  

黄凯  郑田要  朱建华  宋国胜  韩忠  袁德保 《江西农业学报》2008,20(8):95-98

从结构、毒理学分析和灭活方法3个方面对国内外近年来对大豆胰蛋白酶抑制剂的研究进展进行了综述。  相似文献   

50％竹焦油乳油的安全性毒理学评价   总被引：6，自引：4，他引：2  

马建义  王品维  童森淼  鲍滨福  张齐生  沈哲红  叶良明 《竹子研究汇刊》2008,27(2)

为了解50%竹焦油乳油作为农药使用的安全性,按GB 15670-1995农药登记毒理学试验方法进行了安全性评价。结果表明,50%竹焦油乳油对雌雄大鼠经口LD50分别为:雌性3690 mg.kg-1,雄性大于4640 mg.kg-1,均属低毒。对雌雄大鼠经皮LD50均大于2000 mg.kg-1,均属低毒。对兔眼的刺激强度为中度刺激性,洗眼试验结果有轻度刺激性。对家兔急性皮肤刺激反应均值积分为0,即对皮肤无刺激性。对豚鼠致敏试验,致敏率为0%,属级弱致敏。证实50%竹焦油乳油为低毒性、无刺激性、无致敏的安全生物农药。  相似文献   

镉对绵羊的毒理学研究   总被引：11，自引：0，他引：11  

刘宗平  马卓 《畜牧兽医学报》1996,27(6):546-553

本文按每日１ｍｇＣｄ／ｋｇ体重剂量对绵羊口服氯化镉溶液，成功复制出了镉中毒的动物模型。结果表明：（１）实验第２０天左右即出现粘膜苍白、消瘦、血液稀薄、水肿等临诊中毒症状，并且上述症状呈渐进性发展；（２）在试验第２０天或４０天时ＲＢＣ、Ｈｂ、ＰＣＶ、ＭＣＨＣ均显著或极显著低于对照组（Ｐ＜０．０５，Ｐ＜０．０１），红细胞发生了明显的棘形改变，呈一种典型的正细胞低色素性贫血，血清ＢＵＮ、ＴＰ、Ａ１ｂ和Ｔ＿３含量与对照组相比均出现显著差异（Ｐ＜０．０５，Ｐ＜０．０１）；（３）所测生物样品Ｃｄ含量极显著高于对照组，而Ｆｅ含量则明显降低（Ｐ＜０．０１）；（４）病理组织学变化以肝、肾等实质性器官的损害为主。  相似文献   

Sulfur in pesticide action and metabolism: Edited by J. D. Rosen,P. S. Magee,and J. E. Casida,American Chemical Society,Washington, D.C., 1981. 172 pp., $33.00     

W.C. Dauterman 《Pesticide biochemistry and physiology》1982,17(2):205-206

The distribution of ¹⁴C-acid-, ¹⁴C-alcohol-, and ¹⁴C-cyano-labeled deltamethrin and selected metabolites were followed in the liver, blood, cerebrum, cerebellum, and spinal cord after iv administration of a toxic, but nonlethal dose (1.75 mg/kg) to rats. Approximately 50% of the dose was cleared from the blood within 0.7–0.8 min, after which the rate of clearance decreased. 3-Phenoxybenzoic acid (PBacid) was isolated from the blood in vivo, and was also the major metabolite when ¹⁴C-alcohol-labeled deltamethrin was incubated with blood in vitro. Deltamethrin levels in the liver peaked at 7–10 nmol/g at 5 min and then decreased to 1 nmol/g by 30 min. In contrast, peak central nervous system levels of deltamethrin were achieved within 1 min (0.5 nmol/g), decreasing to 0.2 nmol/g at 15 min, and remaining stable until 60 min. peak levels of deltamethrin did not correspond to the severity of toxicity, although the levels of non-pentane-soluble radiolabel did appear to correlate with motor signs of toxicity. Experiments with brain homogenates, using in vivo concentrations of deltamethrin, failed to reproduce the pentane-unextractable radioactivity in vitro nor was any metabolism demonstrated.  相似文献   

Blackboard网络课堂辅助下食品毒理学实验教学范式改革研究   总被引：1，自引：0，他引：1  

刁春英  闫洪波  刘月英  高秀瑞 《安徽农业科学》2015,(5):365-366,368

为提高食品毒理学实验教学效果,在Blackboard网络平台辅助下,建立了食品毒理学实验双主体互动式教学模式,丰富了教学内容,提高了学生的自主学习意识和能力,结合TBL教学法,加强了学生对问题的分析能力并培养了学生的团队合作能力.结果表明:双主体互动式教学模式和TBL教学法促进了师生的交流,激发了学生的学习兴趣,培养了学生的团队精神.  相似文献   

复方新诺明对中国对虾毒性的初步研究     

张培旗  李健  刘淇  王群 《海洋水产研究》2006,27(1):28-34

用药浴的方法,分别研究了复方新诺明对中国对虾幼体的急性毒性、对幼虾生长的影响和中毒的机理。结果表明,无节幼体、蚤状幼体的24h LC50和48h LC50分别为300、355mg/L和232、172mg/L,安全浓度分别为42、12mg/L;用50、100、200mg/L的复方新诺明对幼虾药浴35d,各试验组未见任何临床变化,而100、200mg/L药物浓度对幼虾体长和体重的增长影响极显著(P<0·01)。用300、450、600mg/L的复方新诺明对幼虾药浴16d,结果表明:各实验组对虾食欲下降,随着药物浓度的增大,死亡率升高。各试验组对虾血细胞数目显著下降(P<0·05),血清AST、ALT活性在300、450mg/L浓度组下降,在600mg/L浓度组升高。对中毒虾肝胰脏、鳃和胃组织进行石蜡切片观察,结果表明,3种组织均产生异常变化,出现从细胞肿胀到空泡化、坏死脱落等一系列组织病理学变化。  相似文献