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901.
Meĭshvili NV Chalian VG Rozhkova IaIu 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2008,94(1):20-26
The causes of aggression in coral monkeys have been considered taking into account the composition of conflicting pairs and the forms of aggression. It was established that more than 85% of the aggressive interactions occurring on the background of a group calmness, were noted in a context of avoidance of closeness with an undesirable partner, demonstration of hierarchical status, competition for closeness to a preferable partner, competition for the resources, the defense of an infant, and complications during the play and sexual herding. 相似文献
902.
Baranov AE Rozhdestvenskiĭ LM 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2008,48(3):287-302
The analysis of the original sources showed that there are some differences in approaches to radiation injuries treatment used mainly by Russian and foreign researches in their experiments. In Russian radiobiology the main way was the single usage of high molecular substances of different chemical structure and of natural origin soon after radiation exposure. These substances were designated then as cytokine inductors. Foreign researchers investigated in the beginning analogous substances too, but then--recombinant cytokines exclusively. In native radiobiology the urgent (in limits of 2 h) and early (in limits of 6-24 h) pathogenic therapy develops already for a long time. There are preparations, betaleukine (recombinant human interleukine 1 beta) and dezoksinat (degraded DNA), as results of developing the directions. Both have licenses on the administration at radiation accidents. But the issues of various medicaments optimal combinations in a common scheme of early (in first 24 h) medical help remain undefined accurately. The consensus protocol of radiation injuries treatment in clinic consists of the supportive therapy (aseptic conditions, wide antimicrobic antibiotics, thrombocytes and erythrocytes transfusions) and the myelostimulation therapy by cytokine combinations. The hemopoietic stem cells transplantation in cases of severe radiation damages treatment remains under question in the reason of immunological conflict between a host and a graft. 相似文献
903.
Evseeva TI Maĭstrenko TA Geras'kin SA Belykh ES 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2008,48(3):370-377
232Th and Ce (III) toxic effects and its modifications with caffeine and D,L-buthionine-(S,R)-sulphoximine on Chlorella vulgaris Beijer were studied using an optical density measure after 24 hours growth. Concentrations of 232Th or of Ce--toxic effect relationship were shown to be nonlinear. In the first (nontoxic) concentration range (for Ce 0.036-1.642 micromol/L and for 232Th 0.001-1.551 micromol/L) algae biomass production registered by optical density do not significantly differ from the control one. In the second (toxic) concentration range dose-effect relationship for 232Th is characterized with quadratic dependence and in the case of Ce--with exponential dependence. 232Th radiation component contribution into effect observed is appeared as induction of DNA damages additional to spontaneous at the radionuclide concentration (equal to 0.345 micromol/L) that is three times lower than in case of the non-radioactive chemical analog Ce (1.071 micromol/L). 相似文献
904.
The prolylproline sequence unit is found in several naturally occurring linear and cyclic peptides with immunosuppressive and toxic activity. Furthermore, Pro-Pro units are abundant in collagen, in ligand motifs binding to SH3 or WW domains, as well as in vital enzymes such as DNA glycosylase and thrombin. In all these sequence units a special role is dedicated to conformation in order to successfully fulfill the appropriate biological function. Therefore, a detailed analysis of the basic conformational properties of Pro-Pro is expected to reveal the versatile structural role of this sequence. PCM (polarizable continuum model) calculations on the basis of ab initio and density functional theory investigations using the model peptide HCO-L-Pro-L-Pro-NH2 are presented. Cis-trans isomerism, backbone conformation and ring puckering are studied. A systematic comparison is made to experimental data gained on L-prolyl-L-proline sequence units retrieved from the Protein Data Bank as well as from the Cambridge Structural Database. PCM data are in good agreement with high-resolution X-ray crystallography. Population data derived from energy calculations and those gained directly from statistics predict that 87% of the Pro-Pro sequence units adopt elongated structures, while 13% form beta-turns. Both approaches prefer the same 6 out of the 36 ideally possible backbone folds. Polyproline II unit (t epsilonL t epsilonL), other elongated structures (c epsilonL t epsilonL, t epsilonL t alphaL and t epsilonL t gammaL), type VIa (t epsilonL c alphaL) and type I or III beta-turns (t alphaL t alphaL) altogether describe 96% of the prolylproline sequences. In disordered proteins or domains, Pro-Pro sequence units may sample the various conformers and contribute to the segmental motions. 相似文献
905.
The effects of inbreeding and low temperature on the pattern of homologous chromosome synapsis in ovarian nurse cell nuclei of Drosophila melanogaster strains were studied. Exposure to decreased temperature (16 degrees C) caused a noticeable increase in the rate of asynapses of homologous chromosomes, whereas this effect was insignificant for F30 inbreeding generation. Long-term inbreeding has a substantial effect on the relative positions of chromosomes in the nurse cell nuclei. This is visually evident only in the interstrain hybrids between highly inbred strains LA (F923) and HA (F923) or between either strain and laboratory strain Canton S or the flies from the natural population, where abnormalities in homologous chromosome synapsis are observed in virtually all nuclei. 相似文献
906.
Golubovsiĭ MD 《Genetika》2008,44(7):869-873
Valentin Sergeevich Kirpichnikov is an outstanding Russian biologist, geneticist, and evolutionist. In his work, the true interest to the theory of evolution was harmoniously combined with long-term successful research into fish genetics and breeding. In 1987, Kirpichnikov published a fundamental treatise entitled "Fish Genetics and Breeding," which was immediately translated into English, German, and Japanese and still remains the most comprehensive handbook in this field. The authority of Kirpichnikov was confirmed by his election to the International Association of Aquaculture and an expert of the leading international organization on food and agriculture, FAO, with the United Nations. During the hard years in the history of Soviet biology, the courage and fidelity to the principles in defending the scientific biology and opposing Lysenko's obscurantism won Valentin Sergeevich the deserved name of a "knight of science". His mode of speech at the seminars and in discussions was unhurried, calm, and fitting. Yet especially important moments supplemented his baritone with hard metal modulations, which revealed the concealed passion and conviction in the defended truth. 相似文献
907.
The review gives concepts of analysis of kinetics of complex reactions with the participation of free-radicals. The concepts are based on the comparison of the kinetic curves of the chemiluminescent reactions in the presence of a physical enhancer coumarin C-525 with the simulated kinetic functions. This method was applied to the investigation of the mechanism of a branched-chain reaction of lipid peroxidation in biological and phospholipid membranes as well as to the effect of antioxidants and determination of their activities. It was also used for studying the reaction of the formation of free radicals in the complex of cytochrome c with cardiolipin. This reaction plays a key role in the initiation of apoptosis. 相似文献
908.
Using C-banding method and in situ hybridization with the 45S and 5S rRNA gene probes, six hexaploid species of the genus Avena L. with the ACD genome constitution were studied to reveal evolutionary karyotypic changes. Similarity in the C-banding patterns of chromosomal and in the patterns of distribution of the rRNA gene families suggests a common origin of all hexaploid species. Avena fatua is characterized by the broadest intraspecific variation of the karyotype; this species displays chromosomal variants typical of other hexaploid species of Avena. For instance, a translocation with the involvement of chromosome 5C marking A. occidentalis was discovered in many A. fatua accessions, whereas in other representatives of this species this chromosome is highly similar to the chromosome of A. sterilis. Only A. fatua and A. sativa show slight changes in the morphology and in the C-banding pattern of chromosome 2C. These results can be explained either by a hybrid origin of A. fatua or by the fact that this species is an intermediate evolutionary form of hexaploid oats. The 7C-17 translocation was identified in all studied accessions of wild and weedy species (A. sterilis, A. fatua, A. ludoviciana, and A. occidentalis) and in most A. sativa cultivars, but it was absent in A. byzantina and in two accessions of A. sativa. The origin and evolution of the Avena hexaploid species are discussed in context of the results. 相似文献
909.
Analysis with the polymerase chain reaction showed that the Khlorofill-4 pea Pisum sativum chlorophyll-deficient mutant with reduced stipules has an altered structure of the COCHLEATA (COCH) gene, carrying a new mutant COCH allele. The phenotype of the mutant was described in comparison with another form having reduced stipules (stipules reduced) and the control. Leaves of the coch mutant are smaller and have other proportions than in the control; stipules are absent from leaves of the first nodes and are narrow, bandlike, or spoonlike at later ontogenetic stages. It was concluded that the cell number in the stipule epidermis is reduced in the st and coch mutants compared to the wild type. 相似文献
910.
Petropavlovskaia EA Shestopalova LB Vaĭtulevich SF 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2011,61(3):293-305
The ability to localize endpoints of sound image trajectories was studied in comparison with stationary sound image positions. Sound images moved either gradually or abruptly to the left or right from the head midline. Different types of sound image movement were simulated by manipulating the interaural time delay. Subjects were asked to estimate the position of the virtual sound source, using the graphic tablet. It was revealed that the perceived endpoints of the moving sound image trajectories, like stationary stimulus positions, depended on the interaural time delay. The perceived endpoints of the moving sound images simulated by stimuli with the final interaural time delay lower than 200 micros were displaced further from the head midline as compared to stationary stimuli of the same interaural time delays. This forward displacement of the perceived position of the moving target can be considered as "representational momentum" and can be explained by mental extrapolation of the dynamic information, which is necessary for successive sensorimotor coordination. For interaural time delays above 400 micros, final positions of gradually and abruptly moving sound sources were closer to the head midline than corresponding stationary sound image position. When comparing the results of both duration conditions, it was shown that in case of longer stimuli the endpoints of gradually moving sound images were lateralized further from the head midline for interaural time delays above 400 micros. 相似文献