[The cytogenetic effects of 137Cs gamma quanta]. / Tsitogeneticheskie éffekty gamma-kvantov 137Cs.

The data on the human chromosomal level have been first obtained showing that the values of relative biological effectiveness of the 137Cs radionuclide exceed 1. These findings were allowed for during intracavitary radiotherapy in more than 50 patients with uterine body cancer.

[Dynamics of the radiation conditions and evaluation of the radiation dosage of the inhabitants of Kiev following the accident at the Chernobyl Atomic Electric Power Station]. / Dinamika radiatsionnoi obstanovki i otsenka doz oblucheniia zhitelei Kieva posle avarii na Chernobyl'skoi AES.

The estimation of the effective dose equivalents of exposure to accidental and non-accidental sources was made on the basis of the studying of radiation situation variations in Kiev after the Chernobyl accident in 1986-1989. The total annual effective dose equivalents to the Kiev population from all sources of exposure for 1986-1989 were 9.19, 7.29, 5.34 and 5.03 mSv, respectively. The necessity of radiation health measures aimed at limiting the intake of long-acting radionuclides of Chernobyl nature and reducing the exposure doses by optimizing the x-ray procedure and by regulating the natural radioactivity of building materials are under discussion.

[Assessment of oncogenic risk of the irradiation of the thyroid gland in humans]. / Otsenka onkogennogo riska oblucheniia shchitovidnoi zhelezy cheloveka.

The paper deals with one of the most urgent aspects of irradiation hygiene, namely assessment of risk for irradiation-induced cancers of the thyroid. A model is described to predict high mortality rates of thyroidal cancer in the population due to the catastrophe at the Chernobyl Atomic Power Station. With the model, life-time risk rates involving sex and age at the moment of irradiation, as well as an irradiation mode.

[Health-related evaluation of thyroid irradiation doses in inhabitants of the Ukrainian S.S.R. after the Chernobyl AES accident]. / Gigienicheskaia otsenka doz oblucheniia shchitovidnoi zhelezy zhitelei USSR posle avarii na Chernobyl'skoi AES.

The paper considers the radiation doses of the thyroid gland in the inhabitants from the Ukrainian SSR areas (Kiev, Zhitomir, Chernigov, and Vinnitsa Regions), which have been obtained by instrumental studies of thyroidal radioactivity in May-June, 1986, and calculated by the most conservative single-dose administration model. A hygienic evaluation has been made of the findings, taking into account the age and residence. The cumulative irradiation doses of the thyroid have been estimated for children and adults. Possible late sequelae for the areas in question may account for 1060 and 300 thyroid carcinoma cases during the whole life for children and adults, respectively.

[Thyroid irradiation doses and organization of endocrinological monitoring of the inhabitants of the Ukrainian S.S.R. after the accident at the Chernobyl AES]. / Pogloshchennye dozy v shchitovidnoi zheleze i organizatsiia éndokrinologicheskogo monitoringa zhitelei USSR posle avarii na Chernobyl'skoi AES.

The paper is devoted to one of the most important aspects of the accident at the Chernobyl Nuclear Power Station: thyroid irradiation in the residents of 8 areas in the Ukrainian SSR and the town of Pripyat, affected with radioactive iodine. Irradiation doses, prognosis of medical effects of the accident, methods and practical measures for the organization of endocrinological monitoring of the affected population were thoroughly considered. The authors proposed a scheme of health care of the population in these areas. They also discussed the structure of data bases for analysis of medico-dosimetric information on "iodine" effects of the accident. The main trends in medico-dosimetric problems of the effects of thyroid irradiation were outlined.

[The cytogenetic effects of 22-MeV neutrons]. / Tsitogeneticheskie éffekty 22 MéV neitronov.

22-MeV neutrons affecting the culture of human peripheral blood lymphocytes have been studied for their cytogenetic peculiarities. Linear character of the dependence of chromosome aberrations yield within the dose range of 0.2-4.0 Gy is noted. Relative biological efficiency of 22-MeV neutrons reaches the highest values at low doses (18.8-2.4). Pair fragments and dicentrics prevail in spectrum of aberrations.

[Comparative action of X-rays and fast neutrons on thymus endocrine function]. / Sravnitel'noe vozdeistvie rentgenovskikh luchei i bystrykh neitronov na éndokrinnuiu funktsiiu vilochkovoi zhelezy.

Whole-body exposure of rats to X-rays (4, 6 and 8 Gy) and neutron radiation (1, 1.5 and 2 Gy) causes a dose-dependent inhibition of endocrine function of thymus and death of its lymphoid cells. Shielding of thymus somewhat reduces the degree and duration of inhibition of thymus hormone secretion.

[Characteristics of the RBE of a therapeutic beam of fast neutrons from a U-120 cyclotron]. / Kharakteristika OBE terapevticheskogo puchka bystrykh neitronov tsiklotrona U-120.

RBE of a therapeutic neutron beam obtained at the U-120 Cyclotron by a 9 Be(d, n)10B reaction (13.6 MeV deuterons) was determined. X-radiation of 180 kW was used as a standard. As estimated by the test of 30-day death of rats subjected to whole-body irradiation, RBE of fast neutrons varied from 3.44 to 2.03 within the dose range from 0.4 to 2.7 Gy. As estimated by the growth inhibition (during 60 days) of Guerin's carcinoma inoculated in rat femur RBE varied from 4.68 to 2.76 within the dose range from 2.3 to 12.0 Gy.

[Effectiveness of a fast neutron beam to induce DNA damage in Ehrlich ascites carcinoma cells irradiated in a aqueous phantom]. / Izuchenie éffektivnosti puchka bystrykh neitronov po povrezhdaemosti DNK kletok astsitnoi kartsinomy Erlikha, obluchennykh v vodnom fantome.

The study of damages to DNA molecules of Ehrlich ascites tumor cells exposed in water phantom to fast neutron beam (mean energy of 6 MeV) showed that changes in the extent of DNA injury did not correlate with the absorbed dose distribution at the phantom depth of 8-12 cm, and also that the dose-response function in the phantom was different from that obtained upon irradiation of cells in the air.

[Cytogenetic effectiveness of the therapeutic beam of fast neutrons emitted by the cyclotron U-120]. / Tsitogeneticheskaia éffektivnost' terapevticheskogo puchka bystrykh neitronov tsiklotrona U-120.

The data are reported on the effectiveness of the therapeutic fast neutron beam of the medicobiological complex U-120 (Institute for Nuclear Research, Academy of Sciences of Ukrainian SSR) as determined by the yield of chromosome aberrations in lymphocyte culture of human peripheral blood irradiated in the air and in the water phantom.