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利用体外评价方法(plasmid DNAassay)和原子力显微镜(atomic force microscopy,AFM)直接观测相结合,研究原始多壁碳纳米管(multi-walled carbon nanotubes,MWNTs)、纯化后的MWNTs以及聚乙二醇(polyethylene glycol,PEG)修饰的MWNTs与DNA的相互作用.结果表明:原始MWNTs对质粒的损伤较为严重;纯化后的MWNTs对质粒的损伤有所减弱;而经PEG修饰的MWNTs对质粒的损伤非常小,表现出良好的生物相容性. 相似文献
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杂草稻是栽培稻田中的同种杂草,栽培稻基因通过天然杂交逃逸到杂草稻群体难以避免,但转基因的适合度效应决定其逃逸后能否在杂草稻群体中扩散.为了评估抗虫转基因(Bt/CpTI)的适合度效应,本实验以一个转基因栽培稻品系和两个杂草稻群体的杂交F2代为材料,对含有转基因和不含转基因的F2代群体田间表现进行了分析.结果表明,在自然高虫压环境中,含有抗虫转基因F2代群体的田间表现显著好于不含转基因F2代群体的表现.此外,含有转基因的和不含转基因的F2群体在田间混种时,在15cm×15cm混种密度下群体的表现明显差于20cm×20cm混种密度下的表现,表明存在竞争效应.含有转基因的F2群体在竞争条件下比不含转基因的F2群体有更多性状表现出优势.上述发现对转基因逃逸所带来的生态影响评估提供有价值的参考. 相似文献
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张成岗 《科技导报(北京)》2020,38(15):59-66
近年来发生的与传染病以及生物安全相关事件,如2003年严重急性呼吸系统综合征(SARS)和近期中东呼吸综合征(MERS)等,以及合成生物学技术在人造生命方面的安全风险,提示传染病防控和生物安全的现状不容乐观。如何重构、重建、重塑人类与微生物、尤其是病原微生物之间的关系,已成为重要的现实问题。结合国内外关于人体共生微生物尤其是肠道菌群与慢病相关性的研究进展,从生命起源与协同进化的角度考虑,提出需要正视微生物本身应有的生存空间与生存逻辑,辩证分析并重构人与病毒、人与菌群之间的平衡关系,从人菌共生、人菌共赢的角度出发,通过改善人体共生微生态环境,提高人体免疫力,为传染病防控和生物安全提供新思路。 相似文献
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中国农业转基因生物的安全性管理与评价方法 总被引:5,自引:0,他引:5
本文以转基因植物为例 ,对我国农业转基因生物及其产品的安全性等级、管理与评价方法作了较详细的介绍 相似文献
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E. Kellenberger 《Cellular and molecular life sciences : CMLS》1994,50(5):429-437
Genetic ecology is the extension of our modern knowledge in molecular genetics to studies of viability, gene expression and gene movements in natural environments like soils, aquifers and digestive tracts. In such milieux, the horizontal transfer of plasmid-borne genes between phylogenetically distant species has already been found to be much more frequent than had been expected from laboratory experience. For the study of exchanges involving chromosomally-located genes, more has to be learned about the behaviour of transposons in such environments. The results expected from studies in genetic ecology are relevant for considerations of evolution, biodiversity and biosafety. The role of this new field of research in restoring popular confidence in science and in its biotechnological applications is stressed. 相似文献
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《科学通报(英文版)》2008,(15)
One of the most pressing issues surrounding transgenic oilseed rape cultivation is the potential impact of GM genes entering neighboring non-GM oilseed rape plants, related weeds or closely related wild relatives. Following the principle of a case-by-case for transgenic crop safety assessment, we designed experiments to study pollen-mediated gene flow from herbicide-resistant transgenic oilseed rape to Chinese commercial varieties. The pollen dispersal was detected as the progeny of recipient plants that were identified as glufosinate resistant. The results indicated that pollen dispersal occurred up to 2000 m and its rate sharply decreased as the distance from the pollen source increased. However, the rate of long-distance pollen dispersal from 33 to 2000 m was less than 0.015% and did not present a gradual decrease, indicating the randomization of dispersal and pollination. Most pollen dispersed within a 4.5 m area around the transgenic pollen source plot, with a maximum of 1.19% at the sampling site of 1.4 m. Wind direction significantly affected the direction and the distance of pollen dispersal, resulting in the more and farther dispersal in southwest direction. However, the number of potentially pollinating bees was not correlated with direction and distance from the pollen source plot, suggesting that bee density and distribution would not contribute to the differences in pollen dispersal among different directions. This paper is the first report on research in a large-scale experiment of pollen-mediated gene flow un-der the China’s environmental conditions and provided scientific evidence for the effective commer-cialization of transgenic oilseed rape and its safe management. Our results also provided important data on pollen spatial distribution pattern. 相似文献
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现代生物技术的生物安全问题 总被引:13,自引:0,他引:13
由转基因、生物入侵等引起的生物安全问题是国内关注的焦点。本文论述了生物安全的定义、研究范围和生物安全评价的重要性,还对开放环境中使用微生物菌剂的生物安全性问题进行了阐述。 相似文献