Linear regression analysis for each cell fraction.

CD34+ cells exposed to carbon-ion beams or X-rays at indicated doses were seeded in serum-free liquid cultures. Cell fraction showing significant differences for X-rays or carbon-ion beams on day 14 were used for linear regression analysis. aP = 3.20×10−2, bP = 2.0×10−3, cP = 4.8×10−2, dP = 1.0×10−4, eP = 9.0×10−3, fP = 5.0×10−3, gP = 4.0×10−3, hP = 1.2×10−2, iP = 2.0×10−3.