Wei Z, Pross H D
Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China.
Space Med Med Eng (Beijing). 1998 Oct;11(5):368-70.
The mechanisms of biological effect of charged particles in space was studied through the inactivation effect of very low-density charged particles on very low-density cells at different impact parameters. A small type of microbeam facility with alpha-radioactive source and CN track detector were used. A diploid wild type Saccharomyces cerevisiae served as experimental eukaryotic cell. The correlation between cell inactivation and impact parameter of alpha-particles on cells was obtained through a CCD-camera system. The results showed that inactivation range of 1.13 MeV/u alpha-particles on cell-agarose mixture was about 5.5 micrometers, larger than the sum (about 3.l micrometers) of ion track-penumbra radius and yeast cell radius. The cell inactivation rate was 0.36-0.33. It suggests that multi-hit on a cell is necessary for killing it. However, in case of miss, the inactivation rate may not be zero at certain impact parameters.
通过研究极低密度带电粒子在不同碰撞参数下对极低密度细胞的失活效应，探讨了空间带电粒子的生物效应机制。使用了一种带有α放射源和径迹探测器的小型微束装置。以二倍体野生型酿酒酵母作为实验真核细胞。通过电荷耦合器件（CCD）相机系统获得了细胞失活与α粒子对细胞碰撞参数之间的相关性。结果表明，1.13 MeV/u的α粒子在细胞-琼脂糖混合物上的失活范围约为5.5微米，大于离子径迹半影半径与酵母细胞半径之和（约3.1微米）。细胞失活率为0.36 - 0.33。这表明细胞被杀死需要多次命中。然而，在未命中的情况下，在某些碰撞参数下失活率可能不为零。
