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1. The influence of modifiers on the lubricity of molybdenum disulfide has been investigated. 2. It has been shown that the modifiers can give a twofold to threefold increase in the wear resistance of antifriction coatings produced from MoS2 powder. 3. The effectiveness of modifiers depends on the operating conditions of the friction pair (speed, load, temperature, type of steel, etc.). The most promising modifiers are cadmium pigments, lead sulfide, metal-free phthalocyanine, and organic sulfides.

The congress was timed to coincide with the 100th anniversary of the birth of prof. A. A. Kisel, whose report was devoted to the creative activity of N. P. Savvatimskaya. Speakers at the congress, Minister of Health of the Federation N. A. Vinogradov and Deputy Minister. I. I. Grigorieva, noting the achievements in the medical care of children, outlined a number of tasks that should be performed in the near future (further reduction in infant mortality, elimination of diphtheria, whooping cough, typhoid fever, poliomyelitis, a sharp decrease in the incidence of tuberculosis, rheumatism, pneumonia, gastrointestinal -intestinal diseases).

The proton beam of the 157 MeV synchrotron of the Institute of Theoretical and Experimental Physics was modified for irradiation of prostatic cancer patients. Patient's topometric preparation and method of transperineal irradiation were described. A method of radiotherapy with proton beam boost was applied to 17 patients with different clinical stages of disease. After 6-20 months of the follow-up all the patients have been alive without clinical signs of tumor. In most of the patients radiation reactions of the critical organs were regarded as mild ones. Chronic and long-term radiation injuries were not detected in the patients who lived over 1 year.

Clinical anatomy of the inguinal, pelvic and lumbar lymph nodes was studied in 89 autopsies on adult males. The data on the life-time lymphographic and post mortem examination of the lymph nodes were compared. It was demonstrated that the retroperitoneal lymph nodes in an adult male include 4-20 right-side, 8-16 left-side external and common iliac, 3-13 right-side lumbar, 3-29 left-side and 0-8 intermediate lumbar nodes. It is important that the skeleton-related topography and number of lymph nodes, and the relationship between these parameters and age should be taken into account in making primary and differential diagnosis of various relevant lesions.

The authors compare dose distributions in local irradiation of prostatic cancer using moving methods on distant gamma-units while taking and not taking into account individual structure of body section and bone structures. They propose problems of choice of optimum conditions of gamma-beam therapy in localized prostatic cancer and their solution. Optimum irradiation designs have been found preferable. When individual dose field calculations are impossible to implement, rotational 360 degree irradiation with correction for 8% and absorption in the table of a gamma-therapeutic unit is recommended.

The surface topography of resting (serum-deprived) and proliferating (serum-stimulated) NIH 3T3 monolayer cell cultures has been examined by scanning electron microscopy. During G1 and S periods of the cell cycle the cells exhibited well pronounced surface microvilli localized mainly in the perinuclear zone, whereas serum deprivation led to a relatively smooth surface with few microvilli. The observed differences are not likely to be associated with the degree of cell spreading over the substrate, rather reflecting metabolic peculiarities of proliferating and resting cells.

NIH 3T3 mouse fibroblasts cultured in the medium containing 0.5% serum for 2, 4, 8, 24, 48 and 72 hours were fused to cells stimulated for proliferation by replacing the medium with a fresh one containing 10% serum; DNA synthesis was studied in monokaryons, homo- and heterodikaryons using radioautography and double-labelling technique. Cells that were cultured in the medium with a low serum content for 72 hours exerted their inhibitory effect on the entry of stimulated nuclei into the S period in heterodikaryons, whereas cells deprived of serum for shorter periods failed to exert this effect. It thus appears that in cell fusion studies with NIH 3T3 cells, the effects of endogenous growth inhibitor(s) produced by resting cells may be revealed not earlier than by the 3rd day of serum depletion.

The distribution of the parameter of asymmetry of the wave fronts in EEG on the convexital surface of the cortex during instenon administration is significantly changed in time and becomes normal after 3 hours of observation. This may point to an improvement of the functional state of the brain under the influence of the drug. The most distinct positive dynamics in such conditions were marked in patients with general brain symptoms and transient disorders in the vertebro-basillar system. A transition of desynchronized EEG to hypersynchronized with a subsequent normalization of the structure is apparently conditioned by the central influence of the preparation on the synchronizing areas of the brain reticular formation.

Pathways of lymphatic and hematogenic spread for prostatic cancer were studied versus tumor stage and patients' age. Metastases into regional lymph nodes were the most frequent, while bony and visceral metastases ranked second and third, respectively. Age-related peculiarities of dissemination were identified. The data obtained do not support the traditional standpoint that bones are the most frequent sites of prostatic cancer dissemination.

The authors conducted a follow-up examination of 118 patients who had meningocaccial meningoencephalitis and meningitis in 1971--1974. Besides a neurological examination the authors performed psychological and EEG studies. It was established that the main expressions of the meningococcial infection during the first 2--3 months following the acute period (and in separate cases up to 1 year and more) were: asthenical syndromes of a different degree, diffuse focal symptoms, neuritis of the cranial nerves, distrubed mental activity and changes in the EEG. For these reasons the estimation of the period of restored working capacity after generalized forms of meningococcical infections should always be strictly individual.

The study of patients from 10 foci of acute viral hepatitides for the presence of HBsAg (in the passive reverse hemagglutination test) and anti-hepatitis A virus IgM (in the radioimmunoassay) has shown high frequency and variability in the spread of hepatitis non-A, non-B, the prevalence of adults aged 20-29 years and children aged 2-4 years among persons involved into the epidemic process and the tendency towards an increase in the proportion of hepatitis non-A, non-B in the total number of cases of viral hepatitides in the republic.

A method of dosimetric planning of multifield local irradiation of prostatic cancer using a file of optimized dose fields was proposed (the fields were computed for concrete patients). Basic charts were used to choose a necessary dose field, then the time of irradiation is computed in present directions for each concrete patient. The method was tested during the treatment of 19 patients who were given a course of radiotherapy in an outpatient setting. A continuous course of radiotherapy at a dose of 70-74 Gy was delivered. Radiation reactions of the rectum were insignificant, and they were eliminated without discontinuation of a course of irradiation.

The lethal effect of antitumor nitrosourea chloroethyl derivatives on proliferating (exponential phase of growth) and non-proliferating (stationary phase of growth) cells is observed at a concentration 5-fold less than that of methyl derivatives revealed by the colony-formation technique. 1,3-bis(2-chlororoethyl)-1-nitrosourea is equally effective towards proliferating and non-proliferating cells, but chlorozotocin exerts a primary cytotoxic effect on proliferating cells. 1-methyl-1-nitrosourea at low concentration causes death more readily of proliferating cells than non-proliferating ones. However, studies on proliferative activity during the first hours after treatment with 1-methyl-1-nitrosourea revealed drug sensitivity in cells being at the early stationary phase of growth.

In radiotherapy of patients with prostate carcinoma the microflora of the intestine and its dynamics were studied. The mostly older patients with chronic affections of the digestive tract showed a considerable injury in composition of intestinal microflora. The radioeffects on regions of minor pelvis are accompanied by acute radioreactions and a chronic radiogenic intestinal syndrome that deteriorates the existing disorders of quantitative and qualitative composition of intestinal microflora considerably what, on its part, contributes to maintenance of the pathological process in intestine. In addition to therapeutic remedies to suppress radioreactions on intestine therefore it is appropriate to apply preparations that affect the composition of intestinal microflora in a normalizing manner.

Determination of the specific markers of acute viral hepatitides A and B (HA and HB) by radioimmunoassay demonstrated that in the structure of acute viral hepatitides in children HA prevails in the interepidemic period (49.4%) followed by HB (19.3%), then by a polyetiological group of acute viral hepatitides of obscure etiology (17.2%), then by HA in the presence of chronic HB (9.7%) and combined acute forms of HA and HB (4.3%).

It has been shown that when cells are incubated for a long time without medium change, imuran exerts a much greater effect on the viability of cells in the late stationary phase of growth than in the early stationary phase. When nutrient medium supplemented with 10% serum was changed for the medium with 0.5% serum, or when a partial change of medium (one third of the volume) was carried out daily from day 4, these differences were only slightly pronounced. Thus, the degree of cell response to imuran in the early and late stationary phases of growth depends upon the way of cell maintaining in the resting state.

Use of twice-distilled water or addition of normal equine serum, preheated at 56 degrees C for 30 min and adsorbed with an adsorbent from the diagnostic kit, to normal saline (1 ml of serum per 100 ml of the saline) helps eliminate spontaneous agglutination of the tested diagnosticum during the detection of HBsAg with the use of reverse passive hemagglutination test, when the experiments are carried out in areas with high concentrations of salts and organic substances in the water.

Antithrombotic properties are induced in polymers used in vascular surgery by modifying their surface chemically by introducing heparin by means of quaternary bases. The authors have studied the interaction of heparin with quaternary polyvinylpyridinium bromide. Optimal conditions for obtaining this complex have been established. The complex is insoluble in distilled water but passes partly into solution in the presence of an excess of heparin or in physiologic solution. Using spectral methods and elementar analysis it was found that the interaction of heparin with quaternary polyvinylpyridinium gives rise to a polyelectrolyte complex in which heparin undergoes structural changes, probably pertaining to sulfonamide or sulfoether groups.