Table I. Effect of gramicidin S (GS)-nitroxides on mitigation of the effect of total body irradiation. Time to median survival (50%) and the percentage of mice surviving at 35 days after 9.5 Gy were determined. Mice injected with JP4-039/F14 had the greatest probability of increased survival, a median survival of 20 days after irradiation, while all other groups had a median survival of 17 days or less. Mice treated with JP4-039/F14 also had more survivors at 35 days (33%) compared to the other treatment groups.