[Analysis of the ESR spectra of irradiated liver and hepatoma specimens].

The analysis of ESR low temperature spectra of in vitro gamma-irradiated (1 Mrad) liver, hepatoma 22-a and tumor host liver has been carried out. On the ground of differences in thermostability and relaxation parameters of paramagnetic centres it has been shown, that there is a large amount of different paramagnetic centres in irradiated normal and tumor tissues. The ESR spectra parameters and properties of observed paramagnetic centres are presented. The main result is the detection of a specific "tumor signal" (asymmetrical singlet deltaH = 6, Oe, g = 2.005) and peroxide radical ROO. signal in tumor and tumor host liver.