Search

The paper gives the data characterizing the specific features of formation of an anthropogenic load on water bodies in north regions; sanitary and hygienic criteria for estimating the biological contamination; and the factors that increase the biological productivity of the algal flora; a classification of eutrophic waters is also proposed.

Main trends in utilization of lignin wastes formed in complex wood processing are discussed. Toxicological and hygienic characteristics of lignins and products of their biotransformation and chlorination are presented. Ecology and hygiene of fertilizers, preserving agents, and construction materials based on lignins are evaluated.

Regularities of the formation and spread of pollution of water objects in the area of sewage discharges of the cellulose-paper works were revealed. The bottom nature of water pollution and their change in their contribution in relation to the distance were determined. The bottom pollution of water was comparable with that due to sewage and varied from 46 to 69%. The transformation of organic matter makes a significant contribution to the total water pollution.

The experience of management of 123 patients after tracheostomy and the following prolonged controlled lung ventilation has been summarized. The techniques of tracheostomy and postoperative management that made it possible to decanulate 118 patients without additional surgical interventions have been described. The studies performed using radiopharmacological agents have revealed considerable disturbances of the pulmonary flow, foci of chronic inflammation in tracheal and bronchial cartilages, mediastinal lymph nodes and pulmonary tissue, reduction in pulmonary tissue elasticity and increase of the lung area.

Sanitary-chemical, bacteriological and toxicological characterization of sediments in the regions of the pulp and paper mills sewage letting out are given. Methods of the analytical control are offered.

The paper is concerned with analysis of correlation of the time of appearance of vomit in a person and a mean dose rate of prolonged gamma-radiation in the persons affected at the Chernobyl accident. The data were approximated by power function. For irradiation with a constant dose rate (P) such correlation looks like Tp = 2.48p-0.5, where Tp is the time of the beginning of vomit, hours after the beginning of irradiation. A semiempirical model combining different conditions of irradiation was formed. Prognosis of a severity of lesion with relation to the time of vomit was given for different conditions of irradiation.

The use of modern diagnostic facilities led to a study of the physico-dosimetric, topometric and clinical aspects of radiotherapy of oropharyngeal cancer. The most effective approaches to therapy of oropharyngeal tumors with account of their site, spread and degrees of differentiation were developed. The most effective method was shown to be the combination of gamma-beam therapy (50 Gy) with electron-photon radiation (20 Gy) of an accelerator of 18-20 MeV, radiation exposure of normal tissues being lowered by approximately 10-20% as compared to that in gamma-beam therapy used alone. The use of the above method in 45 oropharyngeal cancer patients resulted in an immediate clinical effect (disappearance of a tumor and regional metastases (if any) in 60% of the patients. The 2-year survival rate calculated by actuarial curves, was 62 +/- 10%.