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目的观察Ｌｉ、Ｃ、Ｆ三种重离子辐射诱发的细胞失活效应。方法用中国原子能科学院核物理研究所的ＨＩ１３串列加速器产生的Ｌｉ（Ｚ＝３，ＬＥＴ＝１００ｋｅＶ／μｍ）、Ｃ（Ｚ＝６，ＬＥＴ＝３００ｋｅＶ／μｍ）、Ｆ（Ｚ＝９，ＬＥＴ＝１０００ｋｅＶ／μｍ）三种离子束以０．５～６．０Ｇｙ剂量设计值照射人支气管上皮细胞系（ＢＥＡＳ－２Ｂ），以１０００个细胞／瓶接种，计算存活分数。结果三种重离子照射细胞后的细胞存活分数与照射剂量呈指数负相关关系，存活分数（ＳＦ，无量纲）与剂量（Ｄ，Ｇｙ）关系的拟合方程分别为Ｓ＝ＥＸＰ（－Ｄ／１．２８）（Ｌｉ），Ｓ＝ＥＸＰ（－Ｄ／１．１８）（Ｃ），Ｓ＝ＥＸＰ（－Ｄ／２．０９）（Ｆ）；辐射敏感参数Ｄ０为１．２８、１．１８、２．０９Ｇｙ，呈单击单靶模型。以６０Ｃｏγ射线的Ｄ０为参比，Ｌｉ、Ｃ及Ｆ离子的相对生物效应值相继是２．５４、２．６７和１．５５。失活截面（σｉ）分别为１２．５、４０．６、７６．５μｍ２。结论Ｌｉ、Ｃ、Ｆ对体外细胞的失活效应大于６０Ｃｏγ射线，细胞失活至少需要一次以上的离子打击。
Objective To observe the cell inactivation induced by three kinds of heavy ion radiation (Li, C and F). Methods Li (Z = 3, LET = 100keV / μm), C (Z = 6, LET = 300keV / μm) and F (Z = 9) were obtained from the HI13 tandem accelerator of Institute of Nuclear Physics, LET = 1000 keV / μm). Three ion beams were irradiated to the human bronchial epithelial cell line (BEAS-2B) at a dose of 0.5-6.0Gy, and the survival rate was calculated at 1000 cells / flask. Results The cell viability scores of three heavy ion-irradiated cells were negatively correlated with irradiation dose. The fitting equations of survival score (SF, dimensionless) and dose (D, Gy) were S = EXP (-D / S = EXP (-D / 1.18) (C), S = EXP (-D / 2.09) (F); the radiation sensitive parameters D0 are 1.28, 1.18 , 2.09Gy, single-click single target model. The relative biological effects of Li, C and F ions were 2.54, 2.67 and 1.55, respectively, based on the D0 of 60Coγ-rays. Inactivation cross-section (σi) were 12.5, 40.6, 76.5μm2. Conclusion Li, C and F have more inactivation effects on cells in vitro than 60Co γ-rays. Inactivation of cells requires at least one ion strike.