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B Ivanov

Publications and source records attributed to B Ivanov.

At least 37 records · Page 2Linked to original sources
PubMed1978

Spontaneous chromosomal aberration levels in human peripheral lymphocytes.

Spontaneous levels of structural chromosomal aberrations in human peripheral lymphocytes were studied cytogenetically in 49 female and 56 male subjects. With a total of 16 267 metaphase spreads examined, 191 cells were found to contain chromosomal aberrations, giving a rate of 1.17%. The rates of individual aberration types were as follows: chromatid fragments, 0.39%; chromosome fragments, 0.71% dicentrics, 0.06%; symmetrical and asymmetrical chromatid exchanges, 0.01%; and rings, 0.006%. There were significant differences in aberration yields between females aged 20--29 yr. and 60--70 yr., whereas males aged 20--50 yr. showed no difference. The two sexes differed significantly in chromatid fragments, chromosome fragments and aberrants cells.

Adult↗
PubMed1978

[Chromosome aberrations in human lymphocytes induced by exposure to different doses of chronic gamma irradiation in vitro].

Non-stimulated with phytohemagglutinin human blood was chronically gamma-irradiated (226Ra, 99 mg) in vitro at 37 derees C. The dose rates were 8.2 (irradiation doses 8.2, 16.4, 41 and 162.2 rads) and 25.3 (irradiation doses 8.4, 16.9, 42.2, 168.2, 337.3 and 506 rads) rads/hour. Quantitative analysis of different types of structural chromosome aberrations was carried out. The data on aberrant cells and dicentrics were statistically interpreted. The frequency of aberrant cells, observed at both dose rates, was statistically described by the equation y = a + bD, where y = 7.11 (+/- 0.56) + 11.38 (+/- 2.32) . 10(-2) D, and y = 5.23 (+/- 0.23 + 13.20 (+/- 1.11) . 10(-2) D at dose rates 8.2 and 25.3 rads respectively. The dicentrics yield was described by the equation y = alphaD + betaD2 + C, where y = 3.19 (+/- 0.22) . 10(-2) D + 7.0 (+/- 0.46) . 10(-5) D2 + 0.42, and y = 5.05 (+/- 0.38) . 10(-2) D + 7.1 (+/- 0.41) . 10(-5) D2 + 0.42 at 8.2 and 25.3 dose rates. Statistically reliable differences in the dicentric yield in lymphocytes irradiated with different dose rates are observed. The results obtained show that the increase in the dose rate results in the increase of the dicentric yield, originated in one-track process, while the dicentric yield from two-track process remains constant.

Cells, Cultured↗
PubMed1978

[Effect of blood storage and nutrient medium on the frequency of chromosomal cell aberrations after subsequent x-irradiation].

Cytogenetic investigations are carried out in order to study the yield of chromosome aberrations depending on storage conditions of intact and X-irradiated blood and 199 nutrient medium containing calf serum in glass and plexiglas bottles at 20 degrees C within 0, 24, 48 and 72 hours. The yield of chromosome aberrations in blood stored in glass for 24, 48 and 72 hours and then X-irradiated at a dose of 250 r is the same as in freshly irradiated (at the same dose) blood. Statistically significant differences in the yield of chromosome aberrations were observed in blood stored for 24, 48 and 72 hours in plexiglas bottles as compared with freshly irradiated and stored in glass before the irradiation (at a dose of 250 r) blood. No chromosome changes in hereditary structures of lymphocytes were observed in non-irradiated blood, incubated with nutrient medium which was stored for 24, 48 and 72 hours in plexiglas bottles and then irradiated at a dose of 250 r. Non-irradiated blood stored for 24, 48 and 72 hours in glass and plexiglas bottles produced the same chromosome aberration yield as fresh non-irradiated blood. Thus, sensibilization of hereditary lymphocyte structures was observed only in X-irradiated blood stored in plexiglas bottles.

Blood Preservation↗
PubMed1977

[Spontaneous chromosome aberrations in the lymphocytes of human peripheral blood].

The authors carried out cytogenetic studies on lymphocytes from human peripheral blood of 105 persons--49 women and 56 men in order to examine spontaneous frequency of the structural chromosomal abberations in the somatic cells. There were 191 cells with abberations (1,17%), out of 16,267 analyzed metaphasic plates. They found 0,39% of chromatid fragments, 0,71% of chromosomal fragments, 0,06% dicentricets, 0,01% of symetric and asymetric chromatid exchanges and 0,006% of rings. There were no statistically significant differences in the discovery of the spontaneous abberations in the examined persons at various age and sex.

Adult↗
PubMed1975

[Studies of the changes in the content of total serum protein and protein fractions of white Wistar laboratory rats in the process of ontogeny].

The authors examined the changes in the content of the total protein and the protein fractions during the process of Ontogeny in the Blood Serum of 10 female and 10 male random bred rats of the Wistar strain. The examinations were carried out on the fifteenth, thirtieth, sixtieth day of age and when the rats were one year old. The authors found that the content of the total protein in the blood serum in both sexes was increased with advancement of age alpha2-, beta- and gamma-globulin fractions showed a tendency to an increase with advancement of age. The fraction albumin + alpha1 globulin was diminished quantitatively with advancement of age in both sexes.

Age Factors↗
PubMed1973

[The phasic radiosensitivity of human lymphocytes to the effects of protons].

The authors presented data on cytogenetic analysis of lymphocytes from human peripheral blood, irradiated at the stage G0 and G2 of the cellular cycle. There was an increase of chromosomal aberrations with an increase of the dose. Furthermore the irradiation at stage G0 caused the formation of aberrations of chromosomal type, but irradiation at stage G2-aberrations of chromatid type. The increase of one-blow aberrations were of linear character at both stages.

Cells, Cultured↗