Abstract
The ovaries of mice in various cyclic phases, of mice injected with P32 at different points of time before death and of mice given different amounts of P32 were studied as regards the possibility of obtaining quantitative methods of studying the irradiation effects on the follicles. The general appearance of the follicles in histological sections, the autoradiographs, the occurrence of nuclear fragmentation, pyknosis and cytoplasmic vacuolization as well as the inhibition of mitoses cannot for various reasons be used for quantitative evaluation. The counting of “blown-up” (“ballooned”) cells and the measurement of apparent follicular diameters seem to permit quantitative studies on the early irradiation effects on the ovarian follicles.