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重离子束注入与生物体的相互作用及遗传诱变的分子机制 总被引:3,自引:0,他引:3
低能重离子与生物体系相互作用及其生物诱变效应的应用研究在我国率先兴起, 并在应用中取得了很大的成就。 介绍了重离子注入与生物有机体的相互作用及其主要的生物学效应, 包括细胞染色体水平、 生理生化效应, 以及对DNA损伤修复、 基因表达、 甲基化修饰的影响。 总结了离子注入诱变的分子遗传学机理的相关研究。 同时分析、 比较讨论了高能与低能离子、 离子束与射线的生物学效应的异同。 提出了离子注入今后的研究方向, 特别指出了离子注入对生物基因表达影响研究的重要性。 As a new mutagenesis technique, low energy heavy ion implantation started in China for the study of interaction effect between incident ions and organism, and great achievements have been obtained in crop breeding. The article reviewed the main biological effects induced by heavy ion implantation, including physiology, biochemistry and genetics effects, on levels of cell and chromosome, gene expression, DNA methylation, DNA damage and reparation etc. It compared the differences in mutagenesis for organism by high energy and low energy ion implantation, as well as γ ray radiaiton. Future investigation topics were proposed, the emphasis of researches in future was pointed out, i.e., the molecular mechanism and effects of gene differential expression of organism treated by ion implantation. 相似文献
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The microstructure modifications of sodium silicate glass induced by 1.2-MeV electron irradiation are studied by x-ray photoelectron spectroscopy and Raman spectroscopy. Depth profile analyses are also performed on the irradiated glass at 109 Gy. A sodium-depleted layer with a thickness of a few tens of nanometers and the corresponding increase of network polymerization on the top surface are observed after electron bombardment, while the polymerization in the subsurface region has a negligible variation with the irradiation dose. Moreover, the formation of molecular oxygen after electron irradiation is evidenced, which is mainly aggregated in the first two-micron-thick irradiated glass surface. These modifications are correlated to the network relaxation process as a consequence of the diffusion and desorption of sodium species during electron irradiation. 相似文献
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大气中二氧化硫的测定,现普遍使用的是以四氯汞盐作吸收液的盐酸付玫瑰苯胺比色法。汞盐吸收液吸收效率高、稳定性好,但用汞量大,对操作人员的健康及环境污染均会带来一定的问题。近年来,在寻找无汞吸收液的工作方面取得了一定的进展。我们参考有关资料,用甲醛-邻苯二甲酸氢钾(KHP)缓冲液作吸收液(以下简称甲醛吸收液),对相应的分析方法作了一定的改进,取得了较好的效果。从而为革除汞吸收液提供了一条可行的途径。 相似文献
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