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Biomedical subjects

I A Ivanov

Publications and source records attributed to I A Ivanov.

At least 19 recordsLinked to original sources
PubMed2001

Elastic positronium-atom scattering using the stochastic variational method.

The stochastic variational method is used in conjunction with stabilization ideas to compute the low energy phase shifts and scattering lengths for positronium-atom scattering. Results are obtained for the Ps-H, Ps- Li+, Ps-He, and Ps-Ps systems. The Ps-H scattering lengths are probably accurate to better than 5% and are the most accurate so far computed. The results for Ps- Li+ and Ps-Ps scattering represent the first published scattering lengths for these systems. The positive scattering length for completely spin-aligned 3Ps-3Ps scattering, namely 2.95a(0), is particularly significant since it demonstrates the feasibility of forming a stable Bose-Einstein condensate of 3Ps atoms.

Journal Article↗
PubMed1996

[The status of the gastric and duodenal mucosa, biopsied from those who worked in the cleanup of the aftermath of the accident at the Chernobyl Atomic Electric Power Station, in an organotypic tissue culture].

Biopsies of stomach and duodenum different regions mucosa obtained from patients with gastroduodenitis (liquidators of consequences of accident in Chernobyl nuclear station--LCA CNS-- and control patients) were studied cultured in vitro. The following are the differences found. Mononuclear cells, differentiating into macrophages were exposed from control biopsies. Mononuclear cells exposed from LCA CNS biopsies formed rosette-like accumulations after mitotic dividing on a distance from the explant. Part of cells within the rosettes acquired processes and formed syncytial structure.

Biopsy↗
PubMed1989

[The significance of early dysfunction of the transplanted kidney].

The paper is concerned with the results of 39 transplantations of the kidney. All the patients received two basic immunosuppressants, namely prednisolone in a dose of 30 mg/day and Cy in a dose of 10-12 mg/kg a day. Within 6 to 11 months, the recipients' survival amounted to 82.5%, that of the organs to 84.5%. In 63.1% of the patients, immediate function of the transplant could be observed. It has been demonstrated that delayed function of the transplant was conjugated with reduction of the survival of the organs and recipients as well as with decrease of the quality of transplant functioning. Delayed function of the transplant might be determined not only by ischemic but also by immunologic injuries to the organ.

Adolescent↗
PubMed1986

[Risk factors and results in kidney transplantation].

The authors analyzed the results of 139 kidney transplantations in 115 patients with chronic renal failure depending on a degree of risk. The most frequent risk factors were poor compatibility, high arterial hypertension, myocardial and valvular lesions and retransplantation. As to the combination of various risk factors 4 types of risk were defined. It was proved that in the 4th type of risk kidney transplantation was inappropriate. In the 2nd and 3rd types of risk sparing immunodepression was indicated.

Graft Rejection↗
PubMed1985

[Utilization of mycelial waste of antibiotic production in the technology of kilned construction materials].

At present the main part of the mycelial waste of antibiotic production is collected in sludge lagoones, discarded to the sewage treatment system or burnt. The mycelial waste is one of the causes of the environmental pollution. It contains a significant quantity of valuable substances, such as lipids, carbohydrates, proteins and amino acids. The inorganic portion of the waste includes the compounds of calcium, magnesium, sodium, iron, silicium and phosphorus. The levels of the above substances in the mycelial waste allow using it as organic mineral additives in making expanded clay aggregate gravel with the use of low quality clay and loam. It may be also used as the burn-out of the raw material charge in making burnt bricks and other burnt building materials. By its calorific value the mycelial waste is equal to brown coal or peat. It was shown that the structural and mechanical properties of the mixtures of the mycelium and clay depended on the moisture content of the composition and the proportion of its components. The mycelial waste provided a decrease in the optimal temperature of burning by 40-50 degrees C. The production tests at the expanded clay aggregate plants showed that the bulk weight of expanded clay aggregate might be lowered by 50-100 kg/m3 and the usual additives with the use of petroleum products might be completely excluded from the technological process. The use of the mycelial waste for manufacture of burnt building materials provides saving of the fuel energy sources and improvement of the quality of the finished product. It is also important from the ecological viewpoint.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Malignant tumors in patients with kidney transplants ].

In this retrospective study we evaluated incidence of malignancies observed among 718 renal transplant recipients with at least 6 months of follow-up. A total of 461 men and 257 women (mean age at transplantation 36.3 +/- 8.3 years) were included. Thirty three out of 718 recipients (4.6%) developed malignant neoplasia: 45.4% of these were Kaposi's sarcomas, 12.1%--cancers of the uterine cervix, 12.1% cancers of the stomach, 12.1%--basal cell carcinomas, 6.06%--posttransplant lymphoproliferative disorder. There was no significant effect of either cyclosporin A doses or OKT3/ATG on the incidence of the tumors. Mean age of transplant recipients with malignancies was statistically higher as compared to those without malignancies (45.5 +/- 8.2 years versus 36.1 +/- 8.4 years, p < 0.00001). The median time from onset of end-stage renal failure (dialysis start) and from the transplantation to the diagnosis of the tumor make up 32 (16-161) and 23 (5-158) months, respectively. One renal transplant patient suffered from multiple myeloma with aggressive course.

Adult↗
PubMedDate not supplied

[A comparative evaluation of the clinical x-ray picture of uremic osteodystrophy before and after parathyroidectomy].

The authors present the results of clinical, x-ray, and biochemical studies carried out in 51 patients with uremic osteodystrophy, treated with hemodialysis, before and after parathyroidectomy. The patients were divided into 4 groups with various patterns of x-ray symptoms. Patients with x-ray signs of fibrous osteodystrophy made up group 1, the second group consisted of patients with a combination of fibrous osteodystrophy and osteomalacia with secondary hyperparathyrosis predominance; the third group, like the second one, included patients with the mixed form of uremic osteodystrophy, but with the predominance of the osteomalacic syndrome; Group 4 patients had no x-ray signs of bone changes, and the diagnosis of uremic osteodystrophy was confirmed by clinical laboratory evidence. Analysis of the clinical and x-ray data before and after parathyroidectomy has brought the authors to a conclusion that such an intervention was effective only in cases with manifest clinical and x-ray symptoms of fibrous osteodystrophy. In Group 2 patients with the mixed form of uremic osteodystrophy and less manifest osteomalacia as against fibrous osteodystrophy, subtotal or partial parathyroidectomy is advisable only in cases when conservative therapy is of no avail and fibrous dystrophy is progressing. Surgical treatment is contraindicated to patients in whom x-ray signs of osteomalacia predominate over fibrous osteodystrophy in the total picture of uremic osteodystrophy; it may result in a rapid progress of osteomalacia.

Adolescent↗