Fluorescence study of Ehrlich ascites carcinoma cells after X-irradiation.

The mechanism of the increase in ultra-violet fluorescence (U.V.F.) intensity of Ehrlich ascites carcinoma cells after X-irradiation were investigated. It was shown that there were two mechanisms: size-dependent (mechanism I) and size-dependent (mechanism II). The basis of mechanism I is most probably an increase in protein content. Mechanism II is related to an increase in the U.V.F. quantum yield, though its biological nature is still unknown.