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Biomedical subjects

A A Vlasov

Publications and source records attributed to A A Vlasov.

At least 19 recordsLinked to original sources
PubMed2005

[Indications and contraindications to extraperitoneal closing external intestinal fistulas].

Prognostic factors of recurrent external intestinal fistulas after extraperitoneal closing them were studied in 74 patients operated on in the Sverdlovsk region clinical hospital N1 in 1990-2004. There were no lethal outcomes. Good results were noted in 40 out of 74 (54.05%) patients. Postoperative complications developed in 34 (45.95%) patients, including 21 (28.38%) recurrent intestinal fistulas. Using the methods of mathematical analysis it was found that the recurrent intestinal fistulas resulted from persisting inflammatory alterations in the tissues of the peritoneal and intestinal walls and also from appearing due to operation mechanical injuries of patency of the intestine canal in the places of suturing the fistulas or the initial ones - in the abducent parts of the intestine. The indications and contraindications are proposed concerning the using, rational technical means of extraperitoneal closing the external intestinal fistulas.

Adolescent↗
PubMed2001

Dependence of the efficiency of a multicapillary column on the liquid phase loading method.

One of the main approaches employed to reach fast chromatographic separation is based on using columns containing up to 1000 capillaries with the diameter size down to 10-100 microm. The efficiency of such columns depends on the dispersion of the capillary radius and on the way of the liquid-film loading. We present general equations describing these effects. Specifically, we show theoretically and experimentally that the separation efficiency can be improved by using the loading methods specially designed in order to take into account correlation between the film thickness and capillary radius.

Chromatography, Gas↗
PubMed1991

[Role of low-molecular factor of the bone marrow in the induction of primary and secondary IgE response to ovalbumin].

It has been found that low molecular weight factor of mice bone marrow cell cultures decreases the level of the IgE-antibodies to ovalbumin in the serum of syngeneic mice in dose-dependent manner, when inoculated simultaneously with the primary or the secondary immunization. The active substrate of the supernatant has been shown to have molecular weight of 8000 D.

Animals↗
PubMed1991

[Effects of phospholipid platelet activation factor on proliferation of B-lymphocytes of the peripheral blood of healthy donors and patients with bronchial asthma].

The influence of the phospholipid platelet activation factor (PAF) was studied on pokeweed mitogen (PWM)-stimulated proliferation of peripheral blood lymphocytes in patients with bronchial asthma and normal subjects. It was found that PAF exerts dose-dependent activation with following suppression mainly on B-cells after its action on the whole population of lymphocytes activated by PWM. Besides, the influence of PAF on lymphocyte proliferation seemed to be mediated by monocytes since removal of monocytes from the whole population of mononuclear cells abolished the lymphocyte activation induced by PWM. Indomethacin inhibits lymphocyte proliferation activation induced by PAF. The results indicate that PAF has an effect on the IgE and IgG synthesis by blood B-lymphocytes in patients with bronchial asthma.

Adult↗
PubMed1989

[The nature of the factors in immune lymph nodes that stimulate humoral and cellular immune reactions].

In the early period after antigen action, cells of the lymph node draining area of antigen injection produce a factor, which after its administration to intact mice, promotes intensified migration of myelopeptide producers in the bone marrow and increases bone marrow suppressor activity. Factor administration produced 2-3-fold increase in macrophage, peritoneal and lymph node count as compared with control, and 2-4-fold increase in humoral and cellular immune response. The factor consists of three easily identifiable components: Ig, MHC class II determinants and antigen determinants, that form unique complex similar to, or identical with the complexes detected in vivo within 3-6 hours after immunization in serum by other authors.

Animals↗
PubMed1989

[Mechanism of suppression of human peripheral blood lymphocyte proliferation by platelet activation factor].

The influence of the phospholipid platelet activation factor (PAF) was studied on PHA-stimulated proliferation of peripheral blood lymphocytes in patients with bronchial asthma and normal subjects. It was found that influencing on the whole population of lymphocytes PAF suppressed proliferation mainly of T-cells. Besides, the influence of PAF on lymphocyte proliferation seemed to be mediated by monocytes since removal of monocytes from the whole population of mononuclear cells abolished the suppression of lymphocyte proliferation induced by PHA. Pretreatment of lymphocytes with PAF antagonist--BL 8705 almost completely blocked the suppression of lymphocyte proliferation induced by PHA.

Adult↗
PubMed1989

[Effects of immune lymph node factors on formation of immunological memory].

Two various fractions have been formed on the sephadex G-200 from culture supernatants of the lymph nodes cells isolated in 6h after immunization of animals by various antigens. The first fraction possessed the main biological properties peculiar to the earlier described factor of the immune lymph nodes (FILN), intensified proliferation of cells of the popliteal lymph nodes and increased the killer activity of peritoneal lymphocytes. Introduction of FILN simultaneously with ram erythrocytes led to more than a five-fold increase of humoral immune response.

Animals↗
PubMed1989

[Suppression by bone marrow cells of the level of specific IgE antibodies in the blood of mice and decrease in the production of IGE by bone marrow cells].

Changes in the level of the specific IgE-antibodies to ovalbumin under the influence of syngeneic cells of a bone marrow were studied. The IgE-response was induced by ovalbumin in mice (CBA X C57Bl/6)F1. The bone marrow cells suspensions (20-30 X 10(6) cells per mouse) from syngeneic donors was inoculated simultaneously with the immunization. It was found that bone marrow cells suppressed both the level of IgE-antibodies in experimental mice serum and the production of IgE by the bone marrow cells of the recipient. The ability to suppress IgE-response remained when erythrocytes, monocytes and T-lymphocytes were removed from inoculated suspensions. The bone marrow cells taken from the mice immunized with ovalbumin, at the stage of a decreasing IgE-response, provided more pronounced suppression, than bone marrow cells taken from intact animals.

Animals↗
PubMed1988

[Results of the treatment of external gastric and duodenal fistula].

Under consideration were results of treatment and causes of the appearance of gastric and duodenal fistulas in 37 patients. Two patients died (one of them had external gastric fistula, the other had a duodenal fistula). Complex conservative therapy gave positive effects in most cases. Operative treatment was used in patients having external fistulas with purulent abscesses and leakage compartments in the abdominal cavity. Lethality was 5.4%.

Adult↗
PubMed1985

[Regulating effect of bone marrow cells on human T-lymphocyte function].

A study was made of the regulatory effect of human bone marrow cells in two experimental systems: lymphocyte proliferation in response to PHA, and spontaneous and PHA-induced production of macrophage migration inhibition factor (MIF) by peripheral blood lymphocytes. It was shown that bone marrow cells inhibit the proliferative activity of stimulated peripheral blood lymphocytes and induced MIF production. The effect of bone marrow cells on spontaneous MIF production was found to be inconclusive.

Bone Marrow↗