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21.
Generation and physicochemical properties of complexes formed by high-molecular thymus DNA and plasmid DNA with synthetic polymers of (dimethyl amino)ethyl methacrylate, (diethyl amino)ethyl methacrylate, and poly(vinyl amine) were studied in solutions of different ionic strength using low-gradient viscometry, electrophoresis, circular dichroism, spectrophotometry, and dynamic light scattering. The complexes were tested for toxicity with T98G cell cultures. Condensation of DNA was shown to occur when the ratio of charged groups in the polycations and DNA exceeded unity. This condensation manifested itself as an increase in the optical density of DNA solutions. Condensation-associated changes in the dimensions of DNA molecules were determined, and phase diagrams of DNA-polycation systems were analyzed in the presence of NaCl. MTT analysis revealed no toxicity of these complexes.  相似文献   
22.
A new type of plasma source with titanium hydride granules used as a hydrogen accumulator was employed to inject a dense, highly ionized plasma jet into the Globus-M spherical tokamak. The experiments have shown that the jet penetrates through the tokamak magnetic field and increases the plasma density, without disturbing the stability of the plasma column. It is found that, when the plasma jet is injected before a discharge, more favorable conditions (as compared to those during gas puffing) are created for the current ramp-up at a lower MHD activity in the plasma column. Plasma injection at the instant of maximum current results in a more rapid growth in the plasma density in comparison to gas puffing.  相似文献   
23.
Dry enzymatic hydrolyzate was derived from the protein containing wastes of the Iceland scallop fishery using the complex of proteinases from the king red crab hepatopancreas. The finished product contains not less than 80% of free amino acids and the lowest peptides. Leucine, isoleucine, arginine, lysine and aspartic acids account for to 50% of free amino acids. The applicability appraisal of proteinaceous hydrolyzate from the wastes of the Iceland scallop fishery to use them as the constituents in the nutrient medium for microorganisms was conducted. The approbation of hydrolyzate in the composition of nutrient medium on the test--cultures indicated the high sensibility and germinating capacity of microorganisms.  相似文献   
24.
We have recently established that LDL of most patients with coronary atherosclerosis differ from the LDL of most healthy subjects by the ability to cause primary atherosclerotic changes, i.e. the accumulation of intracellular cholesterol in the cells of smooth muscle origin cultured from unaffected intima of human aorta. We assumed that patients LDL is modified lipoprotein differing from native LDL by chemical composition. It has been established in the present study that patients LDL has a substantially lower content of sialic acid as compared with the LDL of healthy subjects. Desialylation of native LDL of healthy subjects with neuraminidase makes them atherogenic, therefore, capable of causing the accumulation of intracellular cholesterol similarly to patients LDL.  相似文献   
25.
Destruction of associative caudato-temporal chain was shown to cause disorders in perceptive gnostic functions and thinking processes in freely behaving cats.  相似文献   
26.
Methane was found among the gases evolved during natural wood decay caused by bracket fungi in boreal forests. Methane was detected both in decaying wood and fungal fruiting bodies. A scheme of symbiotic association of wood-degrading fungi and anaerobic microorganisms providing the methanogenesis in the wood was proposed. The scale of mycogenic methane emission has to be consistent with the huge volume of decaying wood in boreal forest ecosystems.  相似文献   
27.
Ratios of 13С/12C and 15N/14N isotopes were identified in different parts and organs of drooping birch (Betula pendula Roth) in preforest-steppe and pine-birch forests of the Middle Urals by mass spectrometry. The data were analyzed and interpreted from the perspective of biochemical processes of carbon and nitrogen metabolism in the leaf, cambial tissue, trunk wood, branches, roots, and in the soil. The lighter isotopic composition of carbon is characteristic for the leaves, trunk cambium as well as fine (<2 mm) roots. The trunk wood is characterized by the basal trend for 13C enrichment. The heavier carbon isotopic composition inversely related to metabolic activity of organs and tissues, in addition, 13С/12C ratio corresponds to the nitrogen content in the organs and tissues, indicating the metabolic control of carbon fractionation in woody plants. The isotopic composition of nitrogen in the aboveground parts of the plant (leaves, trunk cambium, wood) and in the medium and fine roots was significantly depleted in 15N (δ15N varies from 0 to–3‰), while main roots (δ15N = 0.6 ‰) and soil (δ15N = 2.4–6.7‰) were more enriched. The ratio of stable isotopes of carbon and nitrogen is an integrating index of carbon and nitrogen metabolism in plants.  相似文献   
28.
In chronic experiments on cats contribution of the thalamic mediodorsal nucleus to the organization of the processes of generalization and abstraction was studied by means of alternation method. Electrolytic ablation of the nucleus retarded the learning and impeded the initial stages of formation of the generalization function. Mechanisms of thalamic dementia are discussed.  相似文献   
29.
When horseradish peroxidase was injected into the Ep area of the temporal cortex of 5 cats, the distribution of the labelled neurons in the strio-pallidum and in the nucleus of Meynert was similar in all the cases. In the striatum predominantly large cells (in the nucleus caudatus and in the putamen), as well as middle and small (in the putamen) cells were labelled. Comparing the form and size of the labelled cells in the striatum, revealed in Golgi preparations, it is possible to conclude that large labelled neurons correspond to long-axonal sparsely-branching reticular neurons, and middle and small--to long-axonal densely-branching dendroid "spinular" neurons. The large cells of the striatum can be considered as a part of a vast macrocellular ascending system of the forebrain, its preservation maintains the higher integrative functions of the brain.  相似文献   
30.
Enzymatic Hydrolysis of Proteins from Crustaceans of the Barents Sea   总被引:1,自引:0,他引:1  
Enzymatic preparations from king crab hepatopancreas were shown to be capable, in principle, of producing protein hydrolysates. Hydrolysis of protein-containing waste of deep-water prawn and king crab occurs most successfully at pH 8.0–8.5 and 50–55°C for 5–6 h in the presence of 6 g enzyme per kg substrate. The total chemical composition of the hydrolysates, the molecular weight distributions of proteins and polypeptides, and the contents of free amino acids were studied in dry hydrolysates.  相似文献   
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