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61.
S. S. Karpova V. N. Kalaev V. G. Artyukhov V. A. Trofimova L. G. Ostashkova A. D. Savko 《Biology Bulletin》2006,33(1):73-80
Micronucleus frequency in buccal mucosa from the oral cavity of children as well as nucleolar structural characteristics (surface area of single nucleoli as well as their number and type) in the root meristem of seed progeny of birch (Betula pendula Roth) were studied in some districts of Voronezh City and Voronezh Region (Novovoronezh Town, Zemlyansk Village). Similar trends of changes in cytogenetic parameters have been revealed for both subjects. Regression analysis allowed us to generate an equation relating the cytogenetic parameters of birch seed progeny (surface area of single nucleoli) and humans (frequency of micronuclei in buccal mucosa of children). This study can be considered as a result of cytogenetic monitoring of environmental pollution in some areas of Voronezh City and Voronezh Region. 相似文献
62.
In the apical meristem of Allium fistulosum, the relationship between peroxide lipid oxidation, antioxidant activity, proliferative processes, the yield of chromosomal aberrations and duration the exposure to ionized air was studied. Under the influence of air oxygen ions, superoxide dismutase and catalase activities increased, proliferative processes were stimulated, and shifts occurred in the process of lipid peroxidation in cells of A. fistulosum. When these cells were treated with air oxygen for 40 min, hydrogen peroxide and iron sulfate (II) enhanced oxygen biostimulating effect via stimulation of antioxidant enzyme activity and inhibition of lipid peroxidation. Under these conditions, cell proliferation was intensified and the yield of chromosomal aberrations was reduced in A. fistulosum rootlets. When the time of seed treatment with ionized air was increased to 80 min, lipid peroxidation was activated, antioxidant enzyme activity was inhibited, and the yield of chromosomal aberration increased in seedlings. It was concluded that the biostimulating activity of ionized air was mediated by active oxygen species generated in the cell. The accumulation of TBA(thiobarbituric acid)-reactive products was shown to be related to a decrease in antioxidant enzyme activity and an increase in the yield of chromosomal aberrations. It is emphasized that the mutagenic effect of ionized air is associated with generating conditions that support Fenton reaction and OH-radical formation in the cell. 相似文献
63.
Elena V. Ambros Svetlana Y. Toluzakova Lydia S. Shrainer Elena G. Trofimova Tatyana I. Novikova 《In vitro cellular & developmental biology. Plant》2018,54(4):436-443
A new approach for rapid ex vitro rooting and acclimatization of Fragaria × ananassa micropropagated plantlets of two cultivars (“Alpha” and “Festivalnaya”) has been developed using a mechanocomposite based on biogenic silica and green-tea catechins. Two different mechanocomposite treatments were studied: dipping the cut ends of microshoots in the mechanocomposite powder (the dry dip method) and single watering with solutions at concentrations of 0.3, 1.0, and 3.0 g L?1. These variants were compared with pulse treatment of microplants with 30 mg L?1 indole-3-acetic acid (IAA) for 4 h and a control group of microshoots that were moistened with hormone-free ¼-strength MS medium. The frequencies of ex vitro rooting at the end of the acclimatization period (30 d) varied from 24.8 to 99.7%. The dry dip treatment was best (rooting frequency about 100%) with up to 7.15?±?0.54-cm root length, and 6.10?±?0.31 roots per plantlet. Moreover, this study showed that the growth-stimulating effect of this mechanocomposite treatment on root formation resulted in increased rosette height, leaf number, leaf area, and dry weight of aerial parts. Histological analysis of the leaf blades revealed decreased mesophyll thickness of microshoots treated with the mechanocomposite (up to 88.77?±?2.95 vs. 111.51?±?3.56 μm for the control). Morphometric analysis of scanning electron microscopy data showed that mechanocomposite treatments led to increased stomata density and stomata length. These structural changes led to normalization of the water regime and indicated successful acclimatization. The combination of ex vitro rooting and acclimatization reduced the procedure time by 4 wk, and may be used for commercial strawberry micropropagation. 相似文献
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65.
A I Glukhov M E Trofimova S A Gordeev T V Grebennikova S V Vinogradov V I Kiselev V M Kramarov 《Molekuliarnaia biologiia》1991,25(6):1602-1610
The efficiency of phage DNA amplification by the method of polymerase chain reaction (PCR) with Tth DNA-polymerase was studied for optimization of PCR conditions. The effect on amplification efficiency of medium ionic strength and pH, the presence of univalent cations, detergents, gelatin, ATP, pyrophosphate, SH-reagents and ratio of concentrations of Mg and dNTPs, primers and template was studied. It has been found that a pH optimum for PCR with Tth DNA-polymerase varies from 8.5 to 9.0. An ionic strength optimum for PCR is about 0.08. The influence of univalent cations on the activity of Tth DNA-polymerase can be expressed as NH4+ greater than Na+ greater than K+. 0.01% Tween-20 significantly increases the efficiency of PCR and 0.01% gelatin inhibits it. Addition of ATP, pyrophosphate, SH-reagents to the reaction mixture did not increase the yield of PCR product. It has been also shown that for the given PCR-system an optimum Mg/dNTPs molar ratio is within the range of 1.5-2.0. An optimum concentration of each of the pair of primers for this PCR-system is about 0.3 microM. The possibility of PCR-amplification of 500-8500 b.p. DNA fragments has been demonstrated. 相似文献
66.
Influence of a single impulse of magnetic field (MF) of trapezoidal shape with 10 Oe amplitude on neuron electrical activity (EA) of Lymnaea stagnalis was studied. It has been found that both leading and trailing edges of MF impulse separately were able to change EA of the cells. Nevertheless the impulses with a short time between the edges were found to be of small efficiency. It was suggested that the influence of the rotation electric field induced by the leading edge of this pulse was abolished by the influence of that induced by the trailing edge. The efficiency of MF impulse influence increased with increasing the interval between their edges and ran to the maximum during 10 s interval. 相似文献
67.
This paper develops the methodological foundations of agrolandscape-environmental studies and management of agricultural land that are based on the concept of conservation and reproduction of land and other natural resources used in agriculture, soil fertility, productive longevity of agro-ecosystems and agrolandscapes (All-Russian Williams Fodder Research Institute), and the concept of the ecological framework of agricultural landscapes and ecological–economic balance (Moscow State University, Institute of Geography Russian Academy of Sciences). An integrative understanding of the essence of agricultural lands allows us to consider them as natural agricultural systems, which have a specific structure, functions, and links and are interrelated with other agrogeo-ecosystems and geo-ecosystems that form the environment. They supply agricultural products and other side derivatives of their functioning that are associated with the development of negative processes outside their limits. The features of study, construction, and management of agricultural land are determined by the dual nature-productive essence of agrogeo-ecosystems and the presence of three subsystems in them (abiotic, biotic, and anthropogenic). A special role is played by a control and monitoring unit. Agrogeoecosystems are characterized by the presence of three types of relationships (substance-energy, informational, and management); three main functions of agrogeo-ecosystems (productive, environment-forming, and nature-protective); the ability of agrogeo-ecosystems to respond to anthropogenic impacts; the ability of adaptation and recovery; and their distinctive openness and dynamism. The priorities of studies and management of agricultural land are formulated in several principles (systematic approach, emergence, environmental framework, landscape-ecological balance, multilevel and multifactor adaptation, etc.). They are intended to improve the adaptability, sustainability, productivity, and resource-saving and environmental role of agro-ecosystems and agricultural landscapes, which is only possible by creating favorable conditions for their functioning, ensuring a balance between the productive and protective agro-ecosystems and favorable conditions for the development of soil and soil biota, for the active life of major soil-formers (perennial grasses and microbes). 相似文献
68.
V V Novikov M N Trofimova M A Zhil'tsova L Z Biriukova 《Antibiotiki i khimioterapii͡a》1988,33(11):836-838
For cultivating hybridomas in the ascitic form there are usually used female mice BALB/c and not male ones. Efficiency of production of monoclonal antibodies with cultivation of the hybridomas in male and female mice BALB/c was studied comparatively. The animals were stimulated to form ascite by administration of the incomplete Freund's adjuvant or 3 per cent peptone with petrolatum oil. Some parameters of the ascite formation were studied: viability of the hybridoma cells, ascitic fluid formation period and volume, hybridoma cell concentration and titers of monoclonal antibodies in the ascitic fluid. In regard to all the parameters studied the male animals were not inferior to the female ones and in case of one of the hybridomas even surpassed them twofold by the volume of the ascitic fluid formed. This is evident of possible using male mice for mass cultivation of hybridoma cells with a purpose of obtaining preparative amounts of monoclonal antibodies in production of immunodiagnostic agents on their basis. 相似文献
69.
70.
Saulskaya N. B. Burmakina M. A. Trofimova N. A. 《Journal of Evolutionary Biochemistry and Physiology》2022,58(2):500-507
Journal of Evolutionary Biochemistry and Physiology - Nitric oxide (NO) and serotonin play an important role in the functioning of the medial prefrontal cortex, but their interaction has been... 相似文献