DNA damage 6 article 6 controlled study 6 double stranded DNA break DNA Breaks, Double-Stranded 4 DNA Repair 4 Gamma Rays 4 Histones 4 animal cell 4 clonogenic assay 4 female 4 gamma irradiation 4 gamma radiation 4 histone H2AX 4 immunofluorescence 4 ionizing radiation 4 linear energy transfer 4 lithium 4 nonhuman 4 priority journal 4 protein phosphorylation 4 radiosensitivity 4 unclassified drug 4 Animals 2 Basic Helix-Loop-Helix Transcription Factors 2 Biological Markers 2 CHO Cells 2 CHO cell 2 CHO10B2 2 Catalytic subunits 2