Observations and an interpretation of dose-response relationships for cellular transformation in terms of induced (T)
J Calkins1, M Einspenner, E Azzam
1Department of Biomedical Physics, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia.
Abstract:
Both radiation-induced lethality and transformation frequency have been observed to plateau or diminish abruptly at relatively low dose levels and then increase with increasing doses, but at a reduced incremental rate. Discontinuities in dose-response relationships are postulated to correspond to the induction of a repair system ('T' repair) not functional at lower doses, i.e. below the induction threshold dose (Tt). Anomalies (discontinuities) in dose-response relationships and effects of dose fractionation previously noted are qualitatively explained in terms of this model.
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