Radioactivity and life. YK Kudrytski (MD) 1971 Part 17.

did not reveal any substantive narushgtgmy their health. At the same time repeatedly been eafiksirovvno development of chronic radiation sickness in patients receiving doses above current limits.
The great achievement of modern radiation genetics
is the establishment of two fundamental facts. First, the mutation caused by ionizing radiation, was not momentary act srabatyvayuschi.m on a "target hit". In other words, once thought that if the energy of ionizing radiation is absorbed in a chromosome or DNA molecule, immediately, immediately raises the mutation. Recent studies have shown that the absorption of energy: STI radnatsii only begins the process of mutation, kotoryya until the next cell division can result in, or mutation, or restoring the original condition. , U
As a result of this discovery, as the head of the School geneticists sovetskoi Academician NP Dubinin, the need for a new way to consider the whole problem of mutagenesis.
It turned out that during the recovery processes in the nucleus of primary cells izmeneni'y depends on the entire cell. If for any reason, including as a result of irradiation, the normal physiological state of cells is violated, then the recovery processes are suppressed and the probability was raz'Vitiya: ervichnyh changes in the mutation increases. In multicellular op organism, where the vital activity of each cell is controlled by common regulatory mechanisms, the intensity of the recovery processes, of course, depends on the entire body.
Thus, in modern genetics, a close relationship between the processes occurring in the genetic apparatus of the cell nucleus, and the state of the cell and the whole 'body.
The second equally important fact also discovered in recent years is the establishment of a threshold nature of the radiation-genetic changes. NP Dubinin, analyzing the dependence of mutational processes on the dose rate, has come an <the conclusion of the importance of the degree of change and the violation of the recovery processes in the irradiated organism. When the recovery processes under the influence of exposure to high doses enachitelno suppressed, until the complete cessation mugatsionny process largely depends on the value of ~ doz:
Conversely, exposure to low doses, which takes place at nizkoi 'dose may not cause any noticeable changes during recovery. As a result, the dependence of the mutation on the dose will be quite different: the changing nature of this dependence, which reflects the threshold relationship between radiation and mutagenic dose received by the body.