Abstract: | In this paper the mean number N of nucleoli of cell nuclei and the relative frequency PN of cell nuclei with N nucleoli are investigated. To solve the first problem, the stereological model of convex shaped nuclei and nucleoli and the assumption of randomly-isotropically distributed objects in space are used. The model is developed for non-vanishing thickness T of tissue sections. The relationship between the unknown number N of nucleoli in cell nuclei and the mean number n of nucleoli in nuclear sections determined by counting is N = n (D+T)/(d + T). Here D and d are the mean values of caliper diameter for nuclei and for nucleoli, resp. The second problem is illustrated by means of some biomedical examples: The relative frequency PN of cell nuclei with N nucleoli can be approximated by a generalized Poisson distribution in all investigated cases. Therefore the mean nucleolar number N is the essential parameter to describe the frequencies of cell nuclei with different numbers of nucleoli. |