用放射自显影术观察~(14)C脒基硫脲在动物体内的分布和代谢

本文介绍用整体、显微、层析放射自显影技术观察~(14)C-ASU在小白鼠体内吸收分布与排出,揭示~(14)C-ASU在小鼠体内半小时吸收达到高峰并全身分布。~(14)C-ASU化合物在体内仍以原来形式存在,不直接参与体内代谢作用,说明它在体内累积中毒的可能性小。     

稀土与人体健康

我国是稀土大国，稀土的储量及产量均占世界首位。由于稀土应用日益扩大，特别在我国已把稀土大量应用于农业、林业，并正在试用于饲养业作为饲料的微量添加剂，稀土将越来越多地进人人类生存的环境和食物链，近年来人们对稀土的生物学效应十分关注。许多科学工作者为了阐明稀土进人体内到底是有害还是有益，进行了许多研究和报道。     

THE METABOLISM OF TITANIUM AND OTHER ELEMENTS IN WISTER RATS

The concentrations of Ti and Ca, P, K, Fe, Cu and Zn in blood samples were determined by PIXE after a single intravenous and a single oral dosing with titanium- ascorbate (Ti- Vc) in Wister rats. Following the intravenous injection with 50 mg Ti- Vc/kg body weight, the absorption, distribution and clearance in blood could be described by an exponential equation of three terms. After gavaged with 500 mg Ti-Vc/kg body weight, at 1.5 h the content of Ti reached the highest level. The concentration of Ca was increasing, with the absorption, distribution and clearance of Ti in blood. The contents of Fe and K were decreasing. And the contents of Cu and Zn were significantly fluctuating. The effect of Ti on animal growth could be explained by the fact that Ti- Vc supplementation could promote the absorption of Ca.     

混合稀土硝酸盐的毒性研究

本文报告了混合稀土硝酸盐对三种动物的经口半数致死量在539.89～1121.99mg/kg之间,属低毒物质。对家兔皮肤及眼粘膜具有中、轻度刺激作用。用中子活化方法测定稀土元素在大鼠体内吸收摄入量的0.1%以下。主要分布在骨及肝,其次在心和肾。对wiatar种大鼠致畸实验的结果,高剂量组(330.8mg/kg)对胎仔生长及骨骼发育有一定影响,但未见有致畸作用。Ames实验及小鼠骨髓细胞染色体的观察尚未发现有致突效应。