Modifications of Radiation Effects by External Influences

Abstract

It is the aim of this chapter to demonstrate with a few important and typical examples how the biological radiation effect may be modulated by external parameters, apart from those which were already treated in more detail. The time pattern of exposure plays an important role, both fundamentally and practically. With respect to the recent interest in hyperthermia in radiation therapy, the combination of heat and radiation at the cellular level is discussed. Modifications by pharmaceutical agents can only be described by a few examples, mainly repair inhibitors. The last section deals with changes in tonicity to demonstrate the complexity of biological radiation action and may serve as a safeguard to avoid the premature acceptance of too simple mechanistic models.