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11.
Development of arbuscular mycorrhizal (AM) symbiosis with plant root system in term of molecular and cellular events have been analysed. A role of AM symbiosis in plant life has been discussed. Molecular methods for analysis of arbuscular mycorrhizal fungi have been described. 相似文献
12.
Grezina NM Klenovitskiĭ PM Zinov'eva NA Gladyr' EA Konopel'ko IuV Ernst LK 《Tsitologiia》2007,49(3):194-203
Karyotypes of the hybrid cell lines NS-RL-3 (TK- -sheep kidney cells and rabbit lymphocytes) and betaCR-NS (TK- -rabbit beta-cells and TK- -sheep kidney cells) were investigated. It was shown that both hybrid cell lines were characterized by presence of both sheep and rabbit chromosomes, which number and structure varies depending on the cell type and the number of passages. In some cases the aberrant chromosomes were identified. It was observed, that 40-50% of the NS-RL-3 cells survived in culture in the presence of the human blood serum, and also were identified during 7-28 days after their introduction into the organism of the animal. Thus, the partial immunological tolerance of the hybrid cell lines has been suggested. 相似文献
13.
Kaplan AIa Borisov SV Zheligovskiĭ VA 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2005,55(4):478-486
The 16-channel EEG records of 45 adolescents with schizophrenia and 39 healthy adolescents were subjected to statistical combinatorial analysis of 160 elementary EEG characteristics (6 spectral and 4 segmental EEG characteristics for a channel). Employing pattern recognition algorithm "Kora-n", a list of 37 combined EEG patterns was compiled. This list characterized with a minimal error the EEG of healthy adolescents in such a way that none of these characters featured the EEG of adolescents with schizophrenia. Analysis of this list of EEG characteristics suggests that the contrast between EEG of healthy and ill adolescents is the sharpest in the F4, Cz, T3 and O1 derivations. Compared to EEG samples of schizophrenic subjects, EEGs of healthy subjects exhibit lower levels of delta and theta activity mainly in the frontal and temporal regions of the cortex and higher level of alpha activity predominantly in the occipital region. Applicability of the list of EEG patterns for diagnostics of schizophrenia-type disorders of adolescents is discussed. 相似文献
14.
Sulimova GE Kompaniĭtsev AA Kunizheva SS Klimov EA Rakhmanaliev ER Udina IG 《Genetika》2000,36(7):900-907
Ten DNA markers were localized in the human genome by a screening procedure against the radiation hybrid somatic cell panel (GeneBridge 4 RH Panel) using polymerase chain reaction (RH mapping method). DNA markers were developed to nucleotide sequences adjacent to NotI sites of human chromosome 3 (NotI-STS markers) and also to nucleotide sequences of human cDNA (EST markers). Three EST markers mapped (B10164, S16R and 18F5R) were localized in the human genome for the first time. Marker B10164 was found to be homologous to the nucleotide sequence of the BASP1 gene coding a major receptor protein. Markers S16R and 18F5R presumably tagged new genes, because no homologies were revealed among the nucleotide sequences presented in the databases. For four NotI-STS, more precise localization on human chromosome 3 was determined. On the basis of the data obtained, the NotI map may be integrated with other types of physical maps of human chromosome 3. RH mapping with a standard commercial panel of radiation hybrid somatic cells provided a chance to integrate the data obtained into international databases and existing integrated human chromosomal maps. 相似文献
15.
The effect of temperature, nutrition, and density stresses on phenotypic and genetic variation in morphological traits (thorax length, wing length, number of sternopleural and abdominal bristles, and number of arista branches) was examined in Drosophila melanogaster. In addition, the effect of stress on developmental stability measured as fluctuation asymmetry of bilateral traits was analyzed. All of the stresses were shown to increase phenotypic variation and fluctuating asymmetry of bilateral traits. Genetic variation of morphometric traits estimated using the isofemale line technique was higher under stressful than under normal conditions. Biotic and abiotic stresses were similar in their effect on phenotypic and genetic variation. The effect of stress on variability of morphometric traits was generally higher than on that of meristic traits. Possible causes of the increase of genetic variation under stress are discussed. 相似文献
16.
Labyntseva RD Slinchenko NM Veklich TO Rodik RV Cherenok SO Boĭko VI Kal'chenko VI Kosterin SO 《Ukrainski? biokhimicheski? zhurnal》2007,79(3):44-54
Investigation the influence of calyx[4]arenes C-90, C-91, C-97 and C-99 (codes are indicated) on the enzymatic activity of four functionally different Mg2+ -dependent ATPases from smooth muscle of the uterus: actomyosin ATPase, transporting Ca2+, Mg2+ -ATPase, ouabain-sensible Na+, K+ -ATPase and basal Mg2+ -ATPase. It was shown that calixarenes C-90 and C-91 in concentration 100 microM act multidirectionally on the functionally different Mg2+ -dependent ATP-hydrolase enzymatic systems. These compounds activate effectively the actomyosin ATPase (Ka = 52 +/- 11 microM [Ukrainian character: see text] 8 +/- 2 microM, accordingly), at the same time calixarene C-90 inhibited effectively activity of transporting Ca2+, Mg2+ -ATPase of plasmatic membranes (I(0,5) = 34.6 +/- 6.4 microM), but influence on membrane-bound Na+, K+ -ATPase and basal Mg2+ -ATPase. Calixarene C-91 reduce effectively basal Mg2+ -ATPase activity, insignificantly activating Na+, K+ -ATPase but has no influence on transporting Ca2+, Mg2+ -ATPase activity of plasmatic membranes. Calixarenes C-97 and C-99 (100 microM), which have similar structure, have monodirectional influence on activity of three functionally different Mg2+-dependent ATPases of the myometrium: actomyosin ATPase and two ATPases, that related to the ATP-hydrolases of P-type--Ca2+, Mg2+ -ATPase and Na+, K+ -ATPase of plasmatic membranes. Basal Mg2+ -ATPase is resistant to the action of these two connections. Results of comparative experiments that were obtained by catalytic titration of calixarenes C-97 and C-99 by actomyosin ATPase (I(0,5) = 88 +/- 9 and 86 +/- 8 microM accordingly) and Na+, K+ -ATPase from plasmatic membranes (I(0,5) = 33 +/- 4 and 98 +/- 8 nM accordingly) indicate to the considerably more sensitiveness of Na+, K+ -ATP-ase to these calixarenes than ATPase of contractile proteins. Thus, it is shown that calixarenes have influence on activity of a number of important enzymes, involved in functioning of the smooth muscle of the uterus and related to energy-supplies of the process of the muscle contracting and support of intracellular ionic homeostasis. The obtained results can be useful in further researches, directed at the use of calixarenes as pharmaceutical substance, able to normalize the contractile function of the uterus at some pregnancy pathologies in women's. 相似文献
17.
Pavlovskaia ZhI Mikhaĭlova RV Moroz IV Eremin AN 《Prikladnaia biokhimiia i mikrobiologiia》2003,39(1):31-36
Resistance of Penicillium piceum F-648 to hydrogen peroxide under short-term and prolonged oxidative stress was studied. An increase in the activity of intracellular catalase in fungal cells after short-term exposure to hydrogen peroxide was shown. Activation of fungal cells induced by H2O2 depends on H2O2 concentration, time of exposure, and the growth phase of the fungus. Variants of P. piceum F-648 that produced two forms of extracellular catalase with different catalytic properties were obtained due to prolonged adaptation to H2O2. Catalase with low affinity for substrate was produced predominantly by the parent culture and variant 3; however, a high substrate affinity of catalase was observed in variant 5. Variant 5 of P. peniceum F-648 displayed a high catalytic activity and operational stability of catalase in the presence of phosphate ions and the concentration of substrate less than 30 mM at pH more than 7. 相似文献
18.
19.
A large-scale study of short retroposon (SINE) B1 has been conducted in the genome of rodents from most of the known families of this mammalian order. The B1 nucleotide sequences of rodents from different families exhibited a number of characteristic features including substitutions, deletions, and tandem duplications. Comparing the distribution of these features among the rodent families, the currently discussed phylogenetic relationships were tested. The results of analysis indicated (1) an early divergence of Sciuridae and related families (Aplodontidae and Gliridae) from the other rodents; (2) a possible subsequent divergence of beavers (Castoridae); (3) a monophyletic origin of the group Hystricognathi, which includes several families, such as porcupines (Hystricidae) and guinea pigs (Caviidae); (4) a possible monophyletic origin of the group formed by the remaining families, including six families of mouselike rodents (Myodonta). Various approaches to the use of short retroposons for phylogenetic studies are discussed. 相似文献
20.
Khegaĭ II 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2001,87(7):960-964
The cortical actinin contents was found to be higher in the inner medulla of the rat kidney. Tropomyosin was distributed differently: it is lower in the cortex than in outer or inner medulla. The processes controlled by these proteins seem to be important for the vasopressin renal effects, and the irregular distribution of these proteins reflects participation of different renal areas in facultative water reabsorption. 相似文献