为了解水体中铅(Pb)对鱼类早期发育阶段的毒性影响,使用人工受精获得南方鲇(Silurus meridionalis Chen)胚胎和仔鱼为研究对象,以硝酸铅(Pb(NO3)2)为毒物源,探讨研究对象在胚胎期和仔鱼期受到5个(0~400μg/L)不同浓度水平铅持续暴露、...为了解水体中铅(Pb)对鱼类早期发育阶段的毒性影响,使用人工受精获得南方鲇(Silurus meridionalis Chen)胚胎和仔鱼为研究对象,以硝酸铅(Pb(NO3)2)为毒物源,探讨研究对象在胚胎期和仔鱼期受到5个(0~400μg/L)不同浓度水平铅持续暴露、半持续暴露以及暴露后恢复处理条件下,实验鱼鳃、肝脏和肾脏抗氧酶的活性变化以及脑组织中乙酰胆碱酯酶活性情况。结果表明,恢复组实验鱼鳃、肝脏和肾脏组织中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活性在后期恢复过程中呈升高趋势;三种组织中丙二醛(MDA)含量随着胚胎期水体Pb浓度升高而升高。持续组和半持续组实验鱼鳃、肝脏和肾脏组织中TAOC、SOD、CAT活性随着水体铅浓度升高而降低,显著低于对照组(P<0.05),丙二醛含量随着Pb浓度升高而升高,脂质过氧化程度加剧;而相同Pb浓度水平之间,持续组和半持续组实验鱼三种组织中,持续组中TAOC、SOD、CAT的活性和MDA的含量变化大于半持续组。发现:南方鲇胚胎期受重金属暴露,后期恢复饲养,其鳃、肝脏和肾脏组织中T-AOC、SOD、CAT的活性会出现恢复效应;胚胎期和仔鱼期重金属暴露存在叠加效应,且重金属对仔鱼的毒性作用更加剧烈。展开更多
We studied the rate of lead resoprtion in the gastrointestinal tract of the bird and accumulation of this element by organs and tissues different in their morphology and functions. The minimum lethal lead dosage makin...We studied the rate of lead resoprtion in the gastrointestinal tract of the bird and accumulation of this element by organs and tissues different in their morphology and functions. The minimum lethal lead dosage making 1.5 mg/kg of the live body weight leads to reduction of its mass recovering after its resoprtion in the stomach. Accumulation and elimination of lead from the body are related to dynamics of the body weight. The rate of these processes is in direct dependence and significantly different in various tissues and organs. Claws, kidneys, liver and feathers are characterized by very high rate of element accumulation and fat, heart and muscles - by the lowest rate. Intense elimination of lead from the body starts approximately in 2-2.5 months after the gastrointestinal tract is released from it.展开更多
To enhance the stability in humidity is very crucial to hybrid organic-inorganic lead halide perovskites in a broad range of applications. This report describes a coating stratergy of perovskite nanocrystals via poly-...To enhance the stability in humidity is very crucial to hybrid organic-inorganic lead halide perovskites in a broad range of applications. This report describes a coating stratergy of perovskite nanocrystals via poly- methylmethacrylate-introdnced ligand-assisted reprecipita- tion, using the interactions between the Pb cations on the surface of perovskite nanocrystals and the functional ester carbonyl groups in polymethylmethacrylate framework. The hydrophobic framework shields the open metal sites of hybrid organic-inorganic lead halide perovskites from being attacked by water, effectively retarding the diffusion of water into the perovskite nanocrystals. The as-prepared films demonstrate high resistance to heat and moisture. Additionally, the in- troduction of polymethylmethacrylate into ligand-assisted reprecipitation can effectively control the bulk precipitation and promote the stability of the perovskite solution.展开更多
文摘为了解水体中铅(Pb)对鱼类早期发育阶段的毒性影响,使用人工受精获得南方鲇(Silurus meridionalis Chen)胚胎和仔鱼为研究对象,以硝酸铅(Pb(NO3)2)为毒物源,探讨研究对象在胚胎期和仔鱼期受到5个(0~400μg/L)不同浓度水平铅持续暴露、半持续暴露以及暴露后恢复处理条件下,实验鱼鳃、肝脏和肾脏抗氧酶的活性变化以及脑组织中乙酰胆碱酯酶活性情况。结果表明,恢复组实验鱼鳃、肝脏和肾脏组织中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活性在后期恢复过程中呈升高趋势;三种组织中丙二醛(MDA)含量随着胚胎期水体Pb浓度升高而升高。持续组和半持续组实验鱼鳃、肝脏和肾脏组织中TAOC、SOD、CAT活性随着水体铅浓度升高而降低,显著低于对照组(P<0.05),丙二醛含量随着Pb浓度升高而升高,脂质过氧化程度加剧;而相同Pb浓度水平之间,持续组和半持续组实验鱼三种组织中,持续组中TAOC、SOD、CAT的活性和MDA的含量变化大于半持续组。发现:南方鲇胚胎期受重金属暴露,后期恢复饲养,其鳃、肝脏和肾脏组织中T-AOC、SOD、CAT的活性会出现恢复效应;胚胎期和仔鱼期重金属暴露存在叠加效应,且重金属对仔鱼的毒性作用更加剧烈。
文摘We studied the rate of lead resoprtion in the gastrointestinal tract of the bird and accumulation of this element by organs and tissues different in their morphology and functions. The minimum lethal lead dosage making 1.5 mg/kg of the live body weight leads to reduction of its mass recovering after its resoprtion in the stomach. Accumulation and elimination of lead from the body are related to dynamics of the body weight. The rate of these processes is in direct dependence and significantly different in various tissues and organs. Claws, kidneys, liver and feathers are characterized by very high rate of element accumulation and fat, heart and muscles - by the lowest rate. Intense elimination of lead from the body starts approximately in 2-2.5 months after the gastrointestinal tract is released from it.
基金supported by the Thousand Young Talents Programthe National Natural Science Foundation of China (21422507,21635002 and 21321003)
文摘To enhance the stability in humidity is very crucial to hybrid organic-inorganic lead halide perovskites in a broad range of applications. This report describes a coating stratergy of perovskite nanocrystals via poly- methylmethacrylate-introdnced ligand-assisted reprecipita- tion, using the interactions between the Pb cations on the surface of perovskite nanocrystals and the functional ester carbonyl groups in polymethylmethacrylate framework. The hydrophobic framework shields the open metal sites of hybrid organic-inorganic lead halide perovskites from being attacked by water, effectively retarding the diffusion of water into the perovskite nanocrystals. The as-prepared films demonstrate high resistance to heat and moisture. Additionally, the in- troduction of polymethylmethacrylate into ligand-assisted reprecipitation can effectively control the bulk precipitation and promote the stability of the perovskite solution.
