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Some features were revealed after study of 185 patients with various occupational diseases: chronic lead intoxication, bronchial asthma, and disorders caused by fluor. Considering polyetiology and nonspecificity of gastric diseases, the authors could not determine the changes revealed as caused only by occupational exposure.

Examination of 400 workers in Bratsk aluminium plant proved respiratory diseases formation to be influenced by both occupational factors and various toxic chemicals that are released into atmosphere by other industrial polluters. Structure of respiratory diseases is represented mainly by diffuse pneumoconiosis caused by toxic and dust factors. Prophylaxis of those diseases should be aimed not only to better work conditions, but also to specify measures improving regional ecologic situation.

The authors present materials of clinical and hygienic study checking MAC for lead in the air of workplace. The study covered 506 workers of printing, nonferrous metallurgy plants and storage battery production. The study included examination of cardiovascular, nervous, digestive systems and laboratory values and revealed high diagnostic value of serum lead level and low one of urinary lead level. High number of the groups examined and mathematical processing of incomplete selects (Caplan--Meyer assess) proved that intoxication resulted from higher lead concentrations (0.58-0.8 mg/m3). The lead levels of 0.2 mg/m3 in 23.7% of cases induced changes of 2-3 laboratory values-first signs of lead intoxication--and in 5.2% of cases some symptoms of vegetative sensory polyneuropathy were seen. These lead levels are therefore determined as minimally acting. Calculations of probability parameters for health risk helped to set MAC for lead in the air of workplace at 0.05 mg/m3 (this value is accepted by Russian Health Ministry) with mandatory control of serum lead level.

Retrospective and prospective epidemiologic studies revealed features of pathomorphosis and response, defined various pathogenetic mechanisms induced by complex, combined exposure to poisons at work. The article determined main neurologic and hematologic syndromes considered as early and sensitive diagnostic criteria of poisons influence on workers exposed to them. The authors described some variants of course and long-term complications of prolonged exposure to poisons.

A total of 100 miners exposed to antimonate dust concentrations considerably exceeding the MAC were examined, and 16% of the subjects appeared to have chronic bronchitis. No pneumoconioses were diagnosed. The chronic bronchitis was characterized by mild slow course with I degree of ventilation disturbances. Antimonate ore turned out to induce toxic effects and activate some protective mechanisms: phagocytosis, immune response, inhibition of proteases.

Examination of 953 workers exposed to low concentrations of chlorbenzene, tricresol and dimethylfonnamid revealed such functional neural disorders as cardiovascular neurosis. Chlorbenzene and tricresol resulted in hypertonic cardiovascular neurosis, dimethylformamid--in hypotonic one. Occurrence of cardiovascular neurosis grew with the longer length of service.

The specific neurotropic action of rimantadine was demonstrated in mollusk neuron experiments. No specific neurotropic activity of dejtiphorin was found. In combined application, the latter blocked the neurotropic effect of rimantadine. In experiments in white mice and rats, high doses of both drugs decreased the emotional and motor activity of the animals. After the use of the combination of the two drugs the activity of the animals did not differ significantly from that in the controls. The antiviral effect of each drug alone and of combination thereof was similar.

In chronic experiments (4 months) in rabbits, rats, and mice biological effects were investigated from 7 exposure regimen of electromagnetic fields with a frequency of 24 MHz at field strengths of the electric field component of 125, 250, 500, and 1,000 V/m, respectively, and an exposure time of 0.25, 1, and 4 hrs. respectively. The effects on the CNS, the immune and hormone systems, the peripheral blood and on the spermato and embryo genesis were estimated. The results delivered the basis for the introduction of an index. In point of time different limit values are to be determined according to the energetic load. A concrete value for the energetic load 7,200 (V/m)2.h is proposed as maximum allowable field strength of the electric component 300 V/m.

The clinical and hygienic studies performed at the antimonite ore extraction mines in Yakutia revealed that the workers were exposed to high concentrations of polymetallic dusts, containing chromium dioxide, antimony, arsenic and their compounds. 11% of the workers exhibited dust bronchitis, changes in the blood and immune reactivity indices which were due to reactions of adaptation to the Far North climatic conditions and the occupational factors' toxic effects.

A pharmacokinetic study of the antitumor drug oxoplatinum labeled with 191Pt when administered to control mice and mice with B-16 melanoma have shown that distribution of the drug in organs and tissues in both groups of animals is nonuniform. The drug is more tropic to the kidneys, liver, spleen, adrenals, thymus, skin and tumor. Correlation was established between the values of the coefficient ratios of differential accumulation (CDA) of the organ/blood in the final and initial periods of observation and the period of the drug half-life in the organs. The higher the CDA of the organ/blood the longer the period of the drug half-life. The excretion of the drug from the blood and most other organs is described by a bioexponential curve.

A decrease in acid secretion by gastric mucosa was registered 10-14 days after irradiation of the lumbal area in six patients with lymphogranulomatosis who were examined before irradiation, 10-14 days and 3-3.5 months after irradiation. Acid production indices came back to normal 3-3.5 months after irradiation. No changes were revealed in gastric mucosa by morphological examination either before or after irradiation. It is suggested that the decrease in acid secretion is due to functional changes in the stomach in response to irradiation.

The authors present materials on the study of epidemiological efficacy of hospitalization of dysentery patients by statistical analysis (calculation of tendencies, rates of increase, etc.) of the indices of focal morbidity per 1000 contacts in the total number of foci characterized by various periods of isolation of the first patient. The work was carried out on materials of two towns considerably differing by the extent of organization of public services and amenities. The results obtained pointed to the relative epidemiological efficacy of hospitalization of dysentery patients particularly marked at the territory with less favourable living conditions.