Cell line α (Gy-1) control β (Gy-2) control α (Gy-1) IdUrd-sens β (Gy-2) IdUrd-sens α -enhanc factor β -enhanc factor SW 1573 cells Exp growing ip 0.22 ± 0.01 0.022 ± 0.001 0.83 ± 0.06 na 3.8   SW 1573 cells Plateau phase ip 0.17 ± 0.03 0.042 ± 0.004 0.31 ± 0.03 0.047 ± 0.005 1.8 1.1 SW 1573 cells Plateau phase dp 0.09 ± 0.02 0.046 ± 0.002 0.37 ± 0.04 0.033 ± 0.006 4.1 0.7 RUCII cells Exp growing ppi 0.008 ± 0.007 0.025 ± 0.001 0.06 ± 0.02 0.026 ± 0.001 7.5 1.04 R1 cells Exp growing ppi 0.23 ± 0.01 0.068 ± 0.003 0.44 ± 0.05 0.075 ± 0.016 1.9 1.1 V79 cells Exp growing ip 0.18 ± 0.02 0.017 ± 0.003 0.38 ± 0.04 0.023 ± 0.007 2.1 1.4 V79 cells Exp growing ppi 0.15 ± 0.02 0.013 ± 0.003 0.29 ± 0.03 0.016 ± 0.004 1.9 1.2 V 79 cells Plateau phase ip 0.09 ± 0.03 0.026 ± 0.004 0.17 ± 0.02 0.062 ± 0.005 1.9 2.4 V 79 cells Plateau phase dp 0.07 ± 0.02 0.020 ± 0.002 0.30 ± 0.03 0.024 ± 0.004 4.3 1.2 Means with SEM of at least three separate experiments are shown. ip=immediately plated after irradiation; dp=delayed plated after irradiation; ppi=plated prior to irradiation; na=not applicable.

Table 3: Values of the linear-quadratic parameters a and ß and enhancement factors of several cell lines treated with ionizing radiation only and after sensitization with iododeoxyuridine (incubation with 4 µM IdUrd for 72 h).