Radiation track and DNA damage
نویسنده
چکیده
hisarticle provides a brief review of aspects of biophysical modelling in radiation biology. A major concern of radiation biology in the past half century has been the quantification of the health hazards of ionising radiations of different qualities and extrapolation of human cancer risks at high dose and dose rates to low dose and dose rates (UNSCEAR 1993). In the past decade with the accelerated progress in molecular biology techniques and advances in theoretical methods attention has become more focused on mechanistic studies and interpretation of effects of ionising radiation. To this end, track structure has provided a theoretical tool to investigate those parameters of ionising radiation that predominantly determine the nature and magnitude of the final effect (Vogelstein and Kinzler 1998). Radiation oncogenesis is a multistep process including the initiation stage, the promotion or expansion processes, the conversion stage and the final stage of progression. In the initiation stage radiation produces molecular damage by modification of the primary structure of DNA following the passage of the particle through the cell. The initial molecular damage is subject to
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