The search for ways to overcome tumour radioresistance is a major problem of experimental and clinical radiation oncology. The diffi- culties involved in the attempts to solve this problem are a matter of common knowledge. In many a laboratory extensive studies are un- derway of factors determining tumour tissue response to irradiation and of methods for exerting directional effect upon those factors. Such studies have revealed that, at least at the cellular level, a considerable number of factors manifest themselves which are respon- sible for radiation effect (1] * Among those are: spatial...

A mathematician who has taken the romantic decision to devote himself to biology will doubtlessly look upon cell kinetics as the most simple and natural field of application for his knowledge and skills. Indeed, the thesaurus he is to master is not so complicated as, say, in molecular biology, the structural elements of the system, i. e. ceils, have been segregated by Nature itself, simple considerations of balance may be used for deducing basic equations, and numerous analogies in other areas of science also superficial add to one"s confidence. Generally speaking, this number of impression...