Abstract: Apoptosis and/or necrosis related disorders in the mammalian body, namely radiation exposure disorders, chemical exposure and ingestion disorders, neurological disorders and physical trauma disorders, are treated, and their onset is counteracted by preconditioning, by extracting from the mammalian body an aliquot of blood, subjecting the extracted aliquot, ex vivo, to an oxidative stressor such as exposure to ozone gas, a temperature stressor, i.e. temperatures above or below body temperatures, and ultraviolet light, and re-injecting the treated blood aliquot into the mammalian body. The treatment ha the effect of decreasing apoptosis/necrosis in the body, and of pre-conditioning the body better to withstand subsequently encountered apoptosis-inducing events.