[Molecular mechanisms of radiation-sensitizing effects of nitroso compounds: new approaches to the prognosis of their effectiveness].

Basing on the results of EPR investigations and an analysis of literature data an assumption was made of the new factors in the mechanism of the radiosensitizing action of nitro compounds. It was assumed that irradiation-induced accumulation of toxic products of incomplete reduction of the nitro group of these compounds--nitroso- and hydroxyl amino-derivates--in tumor hypoxic zones played the main role in the radiosensitizing action of nitro compounds.