Table 1.

Survival fraction of different dose rate irradiation in CL187 cell line (%, $\overline{x}$ ± s)

	Irradiation dose (Gy)
	1	2	4	6	8	10
Survival fraction
60Co	73 ± 22	49 ± 11	17 ± 5.2	5.7 ± 2.1	1.8 ± 0.19	0.74 ± 0.21
125I	55 ± 18a	28 ± 10b	5.2 ± 2.7c	1.3 ± 0.25d	0.33 ± 0.12e	0.08 ± 0.03f

Compared with ⁶⁰Co group, t = 8.03, ^aP < 0.05; t = 4.85, ^bP < 0.05; t = 13.69, ^cP < 0.01; t = 11.43, ^dP < 0.01; t = 4.76, ^eP < 0.05; and t = 4.62, ^fP < 0.05.