[The morphological and ultrastructural changes in the small intestine of rats with long-term constant exposure to low doses of ionizing radiation]. / Morfologicheskie i ul'trastrukturnye izmeneniia tonkogo kishechnika krys pri dlitel'nom postoiannom vozdeistvii malykh doz ioniziruiushchego izlucheniia.

Variable dystrophic and necrobiotic changes were revealed in epithelial and stromal thin intestine cells in rats who had been living for a long time in Chernobyl and Kiev animal houses. There were no principal differences of these changes in the both groups of animals and their dynamics. The rats that lived in Chernobyl and consumed more polluted food have some special features: crypt mucoidisation, epithelial cell apoptosis, low pinocytic activity of endothelial cells and increase of dense epithelial and capillary cells (coagulation necrosis type).

[The biological effects in animals in relation to the accident at the Chernobyl Atomic Electric Power Station. 3. The morphological and ultrastructural changes in the lungs of rats]. / Biologicheskie éffekty u zhivotnykh v sviazi s avariei na Chernobyl'skoi AES. Soobshchenie 3. Morfologicheskie i ul'trastrukturnye izmeneniia legkikh krys.

The morphological and ultrastructural changes revealed in the lungs of rats kept within the Chernobyl accident zone during the period of 6 to 24 months were shown to be uniform and multicomponent. The changes were found both in the respiratory and the vascular connective tissue. The inflammatory processes occurred with formation of pneumonic foci, hypo- and disatelectasis, emphysematous changes, impairment of interalveolar septa, and connective tissue cell proliferation. In the lung tissue, focal and diffuse lymphoid proliferates and, at later stages, lymphomatous changes were revealed.

[The biological effects in animals in relation to the accident at the Chernobyl Atomic Electric Power Station. 5. Longevity and the carcinogenic effects]. / Biologicheskie éffekty u zhivotnykh v sviazi s avariei na Chernobyl'skoi AES. Soobshchenie 5. Prodolzhitel'nost' zhizni i kantserogennye éffekty.

Remote effects in laboratory animals living in conditions of exposure to a mixture of external and internal radiation resulted from the Chernobyl A.P.S. disaster have been investigated. It has been found that the rate of deaths from non-tumor illnesses grows, the incidence of neoplasms increases and their latency time decreases. The redistribution within the spectrum of benign and malignant tumors and the increase in the multiplicity coefficient have been revealed. It is concluded that chronic exposure of animals to low-level radiation from the radionuclides, resulted from the accident, brings about a much larger number of negative stochastic and nonstochastic remote effects as compared to those expected from the extrapolation of the effects produced by high radiation doses.

[The biological effects in animals related to the accident at the Chernobyl Atomic Electric Power Station. 4. The morphological and ultrastructural changes in the liver of rats]. / Biologicheskie éffekty u zhivotnykh v sviazi s avariei na Chernobyl'skoi AES. Soobshchenie 4. Morfologicheskie i ul'trastrukturnye izmeneniia pecheni krys.

A study was made of the morphological and ultrastructural changes in hepatic tissue of rats lived within the Chernobyl accident zone during the period of 6 to 25 months. Considerable nonspecific changes in hepatocytes (fatty, vacuolar and parenchymatous degeneration, and hepatocyte necrobiosis) were seen throughout the entire period of observation. Coagulation necrosis of certain hepatocytes, Kupffer and endothelial cells, and the development of microcholangiomas by the end of the second year were the most characteristic alterations.

[Morphometric characteristics and functional activity of the cells of Ehrlich ascites cancer found in different phases of the cell cycle]. / Morfometricheskaia kharakteristika i funktsional'naia aktivnost' kletok astsitnogo raka Erlikha, nakhodiashchikhsia v razlichnykh fazakh kletochnogo tsikla.

The Ehrlich ascites carcinoma cells at different interphase periods have been studied for dynamics of ultrastructural and morphometric characteristics and biochemical analysis of metabolism of the given cells has been made. A distinctive structure-function correlation detectable by stage coincidence in the re-structure with the cell metabolism alterations is shown.

[Epithelial-stromal interrelations in mammary gland tumors induced by 7,12-dimethylbenzanthracene in rats]. / Epitelial'no-stromal'nye vzaimootnosheniia v opukholiakh molochnoi zhelezy krys, indutsirovannykh 7,12-dimetilbenz(a)antratsenom.

DMBA-induced mammary tumours in rats are mixed adenocarcinomas with various growth rate (rapid, slow and stabilized). The electron-microscopic study has shown that ultrastructure of tumours and their growth rate depend on a degree of the parenchyma cell differentiation and on the maturity of connective tissue being the result of their specific interaction.

[Modeling of differentiation and physiological involution in the tissues of induced cancer of the mammary gland]. / Modelirovanie differentsirovki i fiziologicheskoi involiutsii v tkaniakh indutsirovannogo raka molochnoi zhelezy.

The experiments used rats with mammary tumors induced by intravenous injection of DMBA. The animals were treated with alternating courses of estrogen and anti-estrogen (tamoxifen). The former was given in combination with papaverin and low doses of vitamin A. This was followed by light and electron microscopic examination of breast tumors which revealed activation of cell differentiation and tissue-specific function. The death of cells (active autolysis) was similar to one taking place in the course of physiologic involution of the organ but it was unlike liquefying and coagulation necrotic processes usually occurring in tumor.

[Involution of rat mammae after abortion, cessation of lactation and vitamin A exposure]. / Involiutsiia molochnykh zhelez krys posle preryvaniia beremennosti, prekrashcheniia laktatsii i vozdeistviia vitamina A.

Structural changes in the mammary gland cells have been studied in rats electron microscopically during pregnancy and involution process after cessation of lactation, as well as at initiation processes by means of abortion at various time of pregnancy (on the 8th, 13th, 20th days). The involutional processes are demonstrated to depend on differentiation degree of the mammary gland cells: intensity of autolytic processes is essentially higher at abortion performed at late stages and at cessation of lactation. Stages of physiological death of the cells are followed. Vitamin A effect on the processes of differentiation and involution is investigated.

[Comparative electron microscopic study of spontaneous and DMBA-induced tumors of mouse mammary glands]. / Sravnitel'noe élektronno-mikroskopicheskoe issledovanie spontannykh i indutsirovannykh DMBA opukholei molochnykh zhelez myshei.

The ultrastructural peculiarities of spontaneous and DMBA induced breast tumours in C3H/He and C3H/Sn mice are described. It is shown that spontaneous breast tumours in mice are highly differentiated adenocarcinomas arisen from acinus against a background of alveolar hyperplasia. DMBA induced breast tumours in mice develop with transformation of ductule-epithelial population of cells. The content and distribution of virus particles are different in spontaneous and DMBA induced breast tumours. The possible transformation of myoepithelial cells is suggested.

[Changes in hepatocyte ultrastructure under the influence of chronic furacillin administration to rats]. / Izmenennia ul'trastruktury gepatotsitov pod vliianiem khronicheskogo vvedeniia krysam furatsilina.

The ultrastructure of rat liver cells was studied during a 6 months' furacilline (5-nitro-2-furtfurilsemicarbazon) feeding in dose of 40 mg per day, and also during the next 8 months after the treatment cessation. An irregular swelling of membranous structure in addition to disorganization and partial reduction of the granular endoplasmic reticulum were found in the hepatocyte cytoplasm after the prolonged furacilline feeding as well as glycogen depletion and the tendency of the agranular endoplasmic reticulum to enlargement. These changes rarely reached the essential intensity with the transition to necrobiosis. They disappeared already a month after the cessation of furacilline treatment. In all the terms of experiment, the nucleoli were hypertrophied and retained their loose nucleoloneme structure. No sings of furacilline carcinogenic activity were found in rat liver during the 14 months of investigation.