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金属硫蛋白对铅的细胞毒性和免疫毒性的保护作用 总被引:4,自引:0,他引:4
金属硫蛋白(MT)是一类低分子量富含巯基的非酶蛋白,其结构特殊。MT具有重金属解毒作用和对生物体所必需的微量元素储存、运输、调节作用,还具有增强机体应激能力,拮抗电离辐射,清除自由基等重要生物学功能。本文主要论证MT与重金属铅对机体的细胞毒性和免疫毒性的保护作用。 相似文献
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对锌和尘肺病因,病理、发病机制以至防治等一系列相关的问题进行了较为全面深入的研究。包括锌抗镍煤尘毒性的模拟实验,锌抗粉尘体外AM毒性研究、锌抗粉尘肺组织细胞毒性研究、锌抗大鼠早期实验性矽肺病变影响的研究以及锌作用机制探讨等五方面的研究内容。 相似文献
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取代苯系列衍生物电子结构与毒性关系的量子化学研究苏忠民,徐贤姬,李金昶(东北师范大学化学系,长春,130024)赵宝忠,盛连喜(东北师范大学环科系,长春,130024)关键词:取代苯衍生物,分子毒性,MNDO采用量子化学半经验AMI、MNDO方法,从... 相似文献
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硒,砷在水稻体内的相互作用及其自由基机理的研究 总被引:11,自引:0,他引:11
以水稻为对象观察了砷(NaAsO2)的毒性作用及硒、砷毒性的相互作用。当培养液中砷(NaAsO2)的浓度约大于0.1×10-6时,砷会抑制水稻的生长。当硒(Na2SeO3)的浓度范围在0×10-5~1×10-6时,硒能拮抗砷的毒性,但硒的浓度大于1×10-6时,硒会增加体系的毒性。有关作用的机理为自由基机理。 相似文献
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雷公滕的药效及毒性与微量元素的研究 总被引:2,自引:1,他引:1
雷公藤是一种药效大、毒性也大的中药。研究了雷公藤的28种无机元素,发现其有益元素铁、锰、锌、硒含量较高,其有害元素铅、砷、镉含量我高,与其药效和毒性一一相对应,雷公藤对风湿性关节炎、肾病、肝脏病、皮肤病的疗效,与铁、锰、锌、硒在人体中生物机理一致。雷公藤对消化道、心血管、肝脏、泌尿系统、造血系统的毒害作用,与铅、砷、镉在人体中的生物学效应一致。所以在使用雷公藤时,应考虑到微量元素作用,可提高雷公藤 相似文献
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The solvation parameter model is used to construct equations for the estimation of the non-specific toxicity of neutral organic compounds to five organisms used for short-term toxicity testing. For the bacteria Vibrio fischeri (Microtox test) and Pseudomonas putida, the protozoan Tetrahymena pyriformis (Tetratox test), the green alga Scendesmus quadricauda and the brine shrimp Artemia salina, the main factors resulting in increased non-specific toxicity are size (dominantly) and lone-pair electron interactions, with hydrogen-bond basicity the most important solute property reducing toxicity. Species differences in relative non-specific toxicity are largely related to differences in cohesion and hydrogen-bond acidity of the biomembranes. The models for non-specific toxicity are proposed as an alternative to the octanol-water distribution constant for the determination of baseline toxicity. Failure of the octanol-water distribution constant to model non-specific toxicity is quantitatively explained by its inability to adequately characterize the sorption properties of the biomembranes for compounds with varied properties. 相似文献
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YUANXing SULi-min SONGLi-li 《高等学校化学研究》2004,20(1):32-35
The single toxicity of aniline and its derivatives and the joint toxicity of the binary mixtures of aniline and each of its derivatives with the toxic unit ratios of 1:1, 1:4, 4:1 to photobacterium phosphoreum were determined, respectively. The toxic unit and the additive index were used to evaluate the joint toxicity. The result shows that the joint toxicity of each of the binary mixtures of aniline and each of its derivatives is mainly simple addition of the toxicities of the two compounds. On this basis, the QSAR equation that was built from the single toxicity of aniline was used to predict the toxicity of the derivatives of aniline in the mixtures. Good agreement between the predicted and experimental values was found with R^2=0. 921. 相似文献
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The role of the substituents at C3 and C8 of jesaconitine (1) on jesaconitine-induced analgesia and toxicity was examined. 3-O-Acetyljesaconitine (2), 3-O-anisoyljesaconitine (3), and 3-deoxyjesaconitine (6) showed dose-dependent analgesic action, and the potency of their compound-induced analgesia and toxicity was lower than those of 1. The most remarkable difference was found in the toxicity. The results indicate that the C3 hydroxy function of 1 participate in the induction of toxicity rather than of analgesia. 8-O-Linoleoyl-14-anisoylaconine (5), 8-O-methyl-14-anisoylaconine (7), 8-O-ethyl-14-anisoylaconine (8), 14-anisoylaconine (4) and 8-deoxy-14-anisoylaconine (9) showed lower activities than jesaconitine-induced analgesia and toxicity. The analgesic activity of 7 was almost the same as that of 8, but the toxicity of 7 was lower than that of 8. The analgesic activity of 9 was lower than that of 4, but the toxicities of both derivatives were not apparent. These facts indicate that the C8 function of 1 is important to the induction of analgesia and toxicity, and also that this function participates differently in the induction of the analgesia and toxicity. Subsequently, it was suggested that substituents at C3 and C8 of 1 played important roles of the induction of the analgesia and toxicity, and that the modes of this participation were not the same in analgesia and toxicity. 相似文献
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O. G. Mekenyan G. T. Ankley G. D. Veith D. J. Call 《SAR and QSAR in environmental research》2013,24(2-3):139-145
Abstract This paper reviews the results of a series of efforts to develop QSAR models for aromatic chemicals whose toxicity is enhanced by the ultraviolet radiation present in sunlight. Photoinduced toxicity of polycyclic aromatic hydrocarbons (PAHs) was found to be a result of competing factors: structural (such as molecular stability and light absorbance) and external (irradiation energy and intensity). These two factors interact, producing a complex, multilinear relationship between toxicity and electronic structure. The HOMO-LUMO gap provided a useful ground-state index to explain the persistence, light absorption, and eventually, the photoinduced toxicity of PAHs. The derived QSAR clearly distinguished phototoxic differences between pairs of structurally similar PAHs, such as phenanthrene and anthracene, benzo [a] anthracene and tetracene, et cetera. Those PAHs exhibiting photoinduced toxicity were consistently within a specific range of the electronic parameter. Further modeling revealed a significant correlation between molecular electronic structure of excited-state PAHs and toxicity. The effect of substituents on photoinduced acute toxicity of PAHs also was investigated. Some substituents such as alkyl and hydroxy moieties do not significantly reduce the HOMO-LUMO gap of parent PAHs. Nitro- and chloro- moieties cause more significant variations of the HOMO-LUMO gap. It is concluded that photoinduced toxicity of PAHs is mainly dictated by the electronic structure of the parent chemicals. Evaluation of the phototoxicity of flexible aromatic molecules (α-terthienyls), generally supported the PAH models. 相似文献
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采用原子类型电拓扑指数(ETSIAT)为结构描述子, 对梨形四膜虫、番茄、红蜘蛛、发光细菌荧光素酶、呆鲦鱼以及鼠的脂肪醇毒性进行了定量构效关系(QSAR)研究. 在偏最小二乘法建立QSAR模型的基础上, 采用内部和外部两种验证方法对模型进行验证. 研究结果表明: ETSIAT可以很好地表征脂肪醇与多种生物毒性相关的结构信息, 所建模型具有良好的稳定性和外部预测能力. 偏最小二乘模型分析结果显示: 疏水性可能是影响脂肪醇毒性大小的主要因素, 其毒性随C链长度的增加而增强, 且相同C原子数的直链脂肪醇毒性明显高于支链脂肪醇; 由于空间位阻效应, 长链脂肪醇与短链脂肪醇可能存在不同的毒性作用机理. 相似文献
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