Szukana fraza: [Abstract = "The paper discusses some mathematical methods, presented in the literature or proposed by the authors, which aim at the estimation of cell kinetic parameters from DNA\-BrdUrd distributions obtained by the pulse labelling technique. In particular, we give an expression for the time behaviour of the relative movement of BrdUrd\-labelled undivided cells, that takes into account the variability of DNA synthesis rate across S phase."]