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Biomedical subjects

Iu I Petunin

Publications and source records attributed to Iu I Petunin.

17 recordsLinked to original sources
PubMed1989

[Quantitative characterization of nuclear polymorphism of the epithelial cells in fibroadenomatosis and cancer of the breast].

A method for quantitative analysis of epithelial cell nuclear polymorphism was suggested, viz. identification of general statistical population using Petunin's criterion. This criterion was employed to assess heterogeneity of visible surface of interphase epithelial cell nuclei and to assay nuclear DNA level in fibroadenomatous hyperplasia and cancer of the breast. Heterogeneity index (h), alongside with other parameters, appeared useful for quantitative assessment of the disease: heterogeneity index values ranging 0.1-0.4 point to pronounced heterogeneity of epithelial cell nucleus surface and DNA level, and are suggestive of malignant transformation of tissue, whereas benign proliferation of the epithelium is usually characterized by 0.4 less than h less than or equal to 0.9.

Adenocarcinoma↗
PubMed1978

[Density of receptor neuron nuclear membrane pores during the early ontogenesis of Gallus domesticus L].

In 10, 14, and 18-day-old embryos, as well as in 3, 14 and 30-day-old chickens, neurons of cerebrospinal ganglia have been studied electron microscopically. A method for quantitative evaluation of pores in nuclear envelope by means of estimating pore density index (PDI) has been suggested. By methods of regressive analysis it has been stated that neuronal development and differentiation in the cerebrospinal ganglion at embryonal and early postnatal ontogenesis of Gallus domesticus are accompanied by a regular increase in density of pores per stipulated unit of the nuclear envelope area. During the studied period of the hen ontogenesis, PDI has a characteristic exponential dependance. A suggestion is made to use the index of the pore density as a criterion for estimating functional state of the receptor neuron.

Age Factors↗
PubMed1976

[Mechanisms of oxygen transport across biological membranes].

Using metallic microelectrodes, intracellular measurements were performed of changes in O2 concentration for spherical oocytes of hens by their replacement from normal (PO2=150 torr) to hyperoxic (to 600 torr) conditions, and vice versa. The curves of O2 influx and efflux were recorded in pulse regime of the working electrode polarization. The character of these curves can be expressed by the following equations: m(t)==c==e=y1t+y0 and m (t) =e-y1t+v0+c, where v1 is determined by the coefficient of cell membrane permeability for O2. Valid differences were shown between values of v1 for oxygen influx and efflux which vanish after the action of cyanides. It is suggested that O2 transport into the cell involves a base component which may be physical diffusion, and an additional component which can be depressed by cyanides.

Animals↗
PubMedDate not supplied

[The cytogenetic assessment of the degree of severity of acute radiation sickness in those who cleaned up the Chernobyl catastrophe].

The study is of a retrospective character and is based on the author's own cytogenetic findings secured in May-June 1986 in the examination of patients diagnosed as having had a first to third-degree acute radiation sickness while receiving massive detoxicating therapy. We consider it expedient to employ the model of multiple linear regression relying on a complex of most informative cytogenetic indicators rather than on only one such indicator alongside the traditional dose reaction identifiable by the level of dicentric chromosomes in blood lymphocytes. This will allow the degree of severity of the radiation injury to be determined with greater precision and permits assessing the therapeutic efficiency of the measures implemented.

Acute Disease↗
PubMedDate not supplied

[Dose curves for radiation-induced cytogenetic damage in human lymphocytes].

Insufficient fitness of experimental data with convenient linear and linear-quadratic models of "dose-effect" dependence for the number of chromosome aberrations of different types were revealed. Proposed method of approximation of the experimental "dose-effect" dependence with piece-linear splines allows to obtain more accurate results in the most cases and therefore is more preferable than the linear and linear-quadratic models.

Cells, Cultured↗
PubMedDate not supplied

[The prognostic significance of cytogenetic, morphological and clinical indices in patients with malignant skin melanoma].

Retrospective estimation of the prognostic importance of parameters, that are different in biological essence, for the persons that have died from malignant melanoma of the skin with use of the adequate mathematical approaches is carried out. A spectrum of important cytogenetic, morphologic and clinical factors which have influence on the prognosis of disease is determined. For group of living patients the prognosed survival time are individually calculated.

Adolescent↗