【摘要】 DNA是生命信息的载体,是辐射生物学效应最重要的靶分子。研究DNA辐射损伤机理,需掌握观测DNA分子及其双链断裂(DoubleStrandBreaks,DSB)碎片的技术。在大气状态下,使用原子力显微镜(AFM)技术获得了3种经提纯的DNA分子的直观图像。在水溶液中,利用Am-α源辐照装置对其中一种DNA分241子作低剂量照射,首次获得了DNA双链断裂碎片的AFM图像。为研究不同类型辐射—特别是重离子辐射—导致的DNA双链断裂几率的统计模型,做了技术准备。更多还原

【Abstract】 DNA , the carrier of bio-information, is the most important target molecule in radiobiology. In order to understand the DSB mechanism of DNA molecules induced by ionizing radiations, the structure and property of DNA molecule and its DSB fragment shall be studied. In this paper, three kinds of purified DNA molecules were ob- served by Tapping Mode AFM in atmosphere. One kind of the DNA molecules in water solution was irradiated by 241Am-α source irradiation device. Intuitive images of the molecules and DSB fragments were obtained. By this way, further study of statistic model of probability of the DSB of DNA molecules induced by various radiations, especially heavy ions, could be carried out.更多还原