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Hydrological and hydrochemical features of the sources of radon- and nitrogen-containing thermal waters of the Altai region are considered. Data on the chemical composition of mineral waters from different sources are presented. Methods for the use of radon- and nitrogen-containing thermal waters from their natural sources of the Altai region for the purpose of sanatorium and spa treatment are described.

Nitrogenase activity, the abundance of diazotrophic bacteria, the structure and functional characteristics of the complex of microorganisms, and the content of nitrogen and carbon were determined in the contents of the gastrointestinal tract of the European beaver. A high nitrogen-fixing activity in the large intestine correlated with an increase in nitrogen content in the chyme upon its transfer over the gastrointestinal tract. It is assumed that microbial nitrogen fixation plays a major role in nitrogen nutrition of the European beaver.

Using Hayman's model of genetic analysis of the F1 hybrids from crosses between early- and late-ripening forms of cotton Gossypium hirsutum L., we examined inheritance of the duration of vegetative period at various contents of nitrogen in soil. Two variants of hybrid plants were studied. With the natural content of soil nitrogen, incomplete directionally dominance of earliness over late ripening with prevalence of additive gene effect of nonallelic interactions was observed. The genetic formulas of this trait proved to change with varying nitrogen nutrition.

The biochemical method for determination of cetyltrimethyl ammonium or cetylpyridinium, both being nitrogenated cationic surfactants, has been devised by using horse blood serum butyrylcholinesterase as analytical reagent. The method streams from the fact that surfactants tested are inhibitors of butyrylcholinesterase hydrolysis of butyrylcholin, a cationic substrate, but in this case they activate enzymatic hydrolysis of 1-naphthylacetate, a neutral substrate. Presence two opposite effects enlarges reliability to identifications. Use the sensitive fluorimetric method to registrations of activation of hydrolysis a substrate 1-naphtylacetate vastly to reduce the threshold of determination of surfactants above.

The procedures of definition amino nitrogen (sum amino acids) and imidazole compounds in human oral fluid are described. Amino nitrogen were determined by the ninhydrin method modified by the authors, imidazole compounds by the Pauli test. A total of over 20 patients with the relatively good dental status were surveyed. The level of amino nitrogen showed noticeable fluctuations (2.01 +/- 1.24 mmol per ml of oral fluid), whereas the content of imidazole derivatives was more stable (0.71 +/- 0.19 mmol/ml). Oral fluid samples displayed an in vitro high proteolytic activity, which explains contradictory results in the determination of the levels of amino nitrogen.

In case of acute hypoxic hypoxia argon in the gas environment is favorable to survivability of laboratory animals (rats). Our purpose was to evaluate effects of an argon-containing hypoxic gas environment on embryogenesis of the Japanese quail (Cortunix cortunix japonica). Eggs of the Japanese quail were incubated in a pressurized chamber with a hypoxic gas environment differing in concentration of nitrogen and argon. In hypoxic (10% O2) oxygen-nitrogen and oxygen-nitrogen-argon atmospheres total mortality of embryos was observed no later than on day 7 of development. These gas mixtures also had a teratogenic effect. However, about 55% of argon in atmosphere prevented completely microcephalia and reduced in half incidence of other pathologies.

The influence of common vole Microtus arvalis on processes of nitrogen fixation and denitrification in the soddy-podsolic soil was studied. In the common vole colonies, the level of nitrogen fixation was reliably lower and that of denitrification higher, than in the control soil outside these colonies. Nitrogen-containing excretory products of voles accumulating in the soil are among the main factors that determine the activity of these processes.

Qualitative and quantitative composition and time course of formation of toxic substances during burning of polymers have been studied for two polymers, P-53-P and STBO. The most toxic gaseous products of nitrogen combustion are listed: hydrogen cyanide, nitrites, acid nitriles, aldehydes, aromatic carbohydrates, alkanes, and carbon oxide. Two expert conclusions are presented, including analysis of blood and viscera from subjects who died during fire. The following toxic substances were detected: carbon oxide, hydrogen cyanide, nitrites, acrylonitrile, acetonitrile, benzene, and methane in one case and the same products except carbon oxide in the other. The author considers that the list of tested toxic substances should be extended, particularly in cases with negative results of blood testing for carbon oxide and carboxyhemoglobin.

The effect of the ammonium nitrate (concentrations 2000, 4000, 6000 mg/l) on the content of urea, urea nitrogen and residual nitrogen in the haemolymph of normal Planorbarius purpura and in trematode-infected individuals. It is shown, that stimulation of metabolic processes is more expressed in uninfected specimens, while the trematode-infected ones, the protective process is strained. When the toxin concentration reaches 6000 mg/l, the trematode infected specimens enter the phase of depression with 3.73% hyponitrogen level.

The review summarizes the literature data on distribution of nitrogen-containing mycotoxins (alkaloids) among Penicillium and Aspergillus fungi infesting grain and products of grain processing. Particular attention in given to clavins (ergotalkaloids) and tremorgens (roquefortine, verruculogen, penitrems).

Nitrogen-containing derivatives of 1,4-naphthoquinone synthesized in the form of donor-acceptor autocomplexes, may serve as highly effective antioxidative agents exhibiting their properties both in microheterogeneous medium (water-micellar Tween 80 solution) and in enzymatic and nonenzymatic oxidation of lipids in mitochondria. Some of these complexes studied, where intramolecular transfer of a charge occurred during nonenzymatic oxidation in mitochondria, were only slightly less effective in the antioxidant activity as compared with the standard antioxidant ionol. Distinct increase in the antioxidant activity of the most substances studied was detected in presence of reductases participating in mitochondrial chains of electron transfer and two of these drugs proved to be more effective as compared with menadione and ionol. The data obtained are of importance for pharmacological prognosis of these new biologically active substances efficiency.

The influence of various nitrogen functional groups used for extraction cleanup and determination of N-containing mycotoxins (NM) in feeds and foodstuffs have been considered. TLC and LC are the most common techniques for detection and determination of nitrogen-containing mycotoxins. Gas chromatography has been used for determination (with or without derivatization) of several nitrogen-containing mycotoxins and/or their degradation products. Immunochemical techniques, in particular ELISA are available for only a very limited number of NM (e.g. ochratoxin A). Numerous methods for determination of ochratoxin A in feeds, grains, animal products and other foodstuffs have been developed. Methods for which recoveries have been carried out on spiked samples are also available for several other NM.

Optimization of the Kjeldahl method for determination of total nitrogen in the objects of microbial synthesis was performed in regard to biomass of the benzylpenicillin-producing culture, activated sludge and certain organic compounds. Mathematical processing of the data was carried out, which showed that the difference in the mean values for the five tested conditions of mineralization was insignificant. The method is useful in assaying the final and intermediate products as well as the waste in biotechnological production.

Significant nitrogen imbalance was recorded in the presence of satisfactory fat retention in premature infants during the first days of life. It is suggested that along with the biochemically immature processes of protein assimilation aggravated by the perinatal pathology protein deficiency plays an important role in the nitrogen imbalance in the premature infants. To prevent the above disorders the authors recommend that the premature infants be given minimum 1.8-2 g protein/kg bw; long-term milk infusions through a naso-gastric tube could be helpful in this case.

The authors report data about the contents of non-protein nitrogen, bound and soluble nitrogen, free amino acids, monocarbonyl compounds and volatile fatty acids as well as about the sum of dinitrophenylhydrazine derivatives of carbonyl compounds and about the microflora. The greatest differences between experimental and control cheeses (produced with rennin) in the contents of the above-mentioned constituents were observed within the first 30 days. On day 60 of experimentation, these differences had smoothed down. It is concluded that a I:I mixture of porcine pepsin and rennin may be used for the production of small medium hard cheeses without impairing their quality of nutritive value.

Nitrous metabolism was studied in children of two age groups (from 1 to 6 months and from 7 to 12 months) living in Frunze. Metabolism studies were carried out for 2 days. Subject to study was balance, retention assimilation of nitrogen and the content of urine nitrous fractions; urea, ammonia, creatine and creatinine. Nitrous metabolism in children under one year was characterized by intensive protein turnover under the climatogeographic conditions of the city of Frunze.

The nitrous composition of meat in 19 species of oceanic sharks and 2 species of rays were analyzed. The meat of these fish species was found to be characterized by a comparatively low protein content, whose amino acids composition proved relatively poor of essential amino acids. The meat of sharks and rays is distinguished by a high level of extractives, whose bulk includes urea and trimethylaminoxide.

A procedure for preparation of samples is described for emission-spectroscopic estimation of 15N in ammonia, glutamic aspartic acids, leucine and glycine using 15N-analyzer NOI-5. The assay involved separation of ammonia and amino acids by means of ion exchange chromatography, degradation of amino acids to ammonia its isolation by microdiffusion from buffers and subsequent reduction of ammonia to nitrogen. Amount of nitrogen in the samples was about 20 mg. The procedure enabled to estimate the content of 15N in ammonia and amino acids of physiological fluids.

A method is described for preparation of nitrogen samples and estimation of 15N concentration in free amino acids and urea, isolated from heart muscle, using mass-spectometric analysis. Components of the tissue extracts were separated at the preparative scale; amino acids and urea were desalted by means of ion exchange chromatography. CHN-analyzer was used to measure content of nitrogen in urea and amino acids. The method required about 100 micrograms of nitrogen for the isotope analysis.

A method of instrumental photonuclear activational analysis is developed for estimation of nitrogen, fluorine and phosphorus in bone tissue samples. The irradiation with maximal energy 15.6 MeV, obtained on linear accelerator of electrons LUE-25 RIMR AMN USSR, was used for activation. Estimations were carried out by the relative method with recording the intensity of positron radiation of 13N, 18F and 30P in samples and standards by means of device for gamma-gamma-coincidence. In chosen regimens of the analysis the statistical errors of nitrogen and phosphorus estimation did not esceed 1.5%, of fluorine-5%; the sensitivity of the method for nitrogen was found to be 0.06% for fluorine-0.006%, for phosphorus-0.12%; on analysis of recovery the relative standard deviation in results accounted for nitrogen-5.4%, for fluorine-6.7% for phosphorus 6.2%. Correctness in concentrations of the elements, estimated by the method described, correlated with the data, obtained in activation with reactor neutrons and with 14MeV generator neutrons.