The purpose of this study is to evaluate the sublethal damage (SLD) repair effect in prolonged proton irradiation using the biophysical model with various cell‐specific parameters of (α/β)_x and T_1/2 (repair half time). At present, most of the model‐based studies on protons have focused on acute radiation, neglecting the reduction in biological effectiveness due to SLD repair during the delivery of radiation. Nevertheless, the dose‐rate dependency of biological effectiveness may become more important as advanced treatment techniques, such as hypofractionation and respiratory gating, come into clinical practice, as these techniques sometimes require long treatment times. Also, while previous research using the biophysical model revealed a large repair effect with a high physical dose, the dependence of the repair effect on cell‐specific parameters has not been evaluated systematically.

中文翻译：

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剂量递送时间对具有各种生物学参数的质子辐照中生物学有效性的影响。

这项研究的目的是使用具有（α / β）_x和T _1/2各种细胞特异性参数的生物物理模型评估质子长时间照射中的亚致死损伤（SLD）修复效果（维修一半时间）。目前，大多数基于模型的质子研究都集中在急性辐射上，而忽略了由于在放射过程中进行SLD修复而导致的生物有效性下降。然而，随着先进的治疗技术，例如超分割和呼吸门控，进入临床实践，对生物有效性的剂量率依赖性可能变得更加重要，因为这些技术有时需要较长的治疗时间。此外，尽管先前使用生物物理模型进行的研究显示，在高剂量下修复效果大，但修复效果对细胞特异性参数的依赖性尚未得到系统评价。