No abstract available

[en] Ionizing radiation effects on the gem cells, which can result in genetic abnormalities, are described. The basic mechanisms of radiation interactions with chromosomes, or specifically DNA, which can result in radiation induced mutation are discussed. Methods of estimating genetic risks, and some values for quantitative risk estimates are given. (U.K.). 13 refs., 2 figs., 1 tab

No abstract available

[en] A formal calculated estimate of total mutagenic effectivity of ¹⁴C evenly distributed in the carbon of organism is presented as a statement of the problem. The value obtained is at least 4000 which is 2 to 3 orders of magnitude greater than the experimental values for ¹⁴C found by other authors. Possible reasons for such discrepance are presented. It is suggested that natural radiocarbon may be one of the basic natural mutagens and sources of gene pool replenishment. The use of ¹⁴C as an effective mutagen in radiation selection is proposed

[en] Differential DNA damage has three levels of complexity; number of lesions per site, identity of lesions, and distances apart of individual lesions. Modelling of such damage is severely limited by the lack of information on parameters of damage induction. Measurement of damage will be difficult in DNA extracted from irradiated cells, while it may be accomplished by use of a valid model system. (author)

[en] The ultimate aim for radiation induced cancer modeling must be to arrive at cancer risk estimates in the human, based (partly or entirely) on data obtained in the laboratory. Current risk estimates for the stochastic radiation effect of cancer induction derive entirely from epidemiological data, largely of the Japanese survivors of the A-bombs, with little input of laboratory information. These data relate to high doses and high dose-rates and it is difficult to see how much more information can be extracted from them. Because of rapid progress in many fields, including molecular biology, cellular studies and experiments with laboratory animals, it is argued here that the time is now ripe for an attempt to be made to model the entire sequence of events from the absorption of radiation energy to the manifestation of a malignancy in the human. (author)

[en] This article discuss the occurrence of mutations in germ cells by ionizing radiation. (H.W.). 11 refs.; 2 tabs

[en] Problems encountered in modelling radiation carcinogenesis are examined in the light of the available experimental information and discussed in view of existing attempts. The role of endogenous and exogenous factors is considered. (author)

[en] Short communication

No abstract available