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排序方式: 共有1476条查询结果,搜索用时 31 毫秒
51.
Ilya G. Kichigin Massimo Giovannotti Alex I. Makunin Bee L. Ng Marsel R. Kabilov Alexey E. Tupikin Vincenzo Caputo Barucchi Andrea Splendiani Paolo Ruggeri Willem Rens Patricia C. M. O’Brien Malcolm A. Ferguson-Smith Alexander S. Graphodatsky Vladimir A. Trifonov 《Molecular genetics and genomics : MGG》2016,291(5):1955-1966
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Exposure of heparinized human venous blood that was diluted with a phosphate buffer to a combination of a static magnetic field (42 µT) and a weak (amplitude range 108–3440 nT) variable low-frequency (1, 4.4, and 16.5 Hz, ratio of amplitudes 6: 1: 1.6, respectively) magnetic field collinear to the static magnetic field enhanced blood chemiluminescence that was induced by the addition of luminol or lucigenin at physiological temperature. The free-radical scavenger edaravone (MCI-186) and apocynin, an inhibitor of NADPH oxidase, reduced the intensity of blood chemiluminescence and alleviated the effects of the magnetic fields. 相似文献
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N. V. Shumskaya O. R. Uzbekova V. Yu. Novikov V. A. Mukhin 《Applied Biochemistry and Microbiology》2016,52(5):558-563
In this study, we investigated chitin hydrolysis by the bacteria inhabiting the ground of the Barents Sea. Four microbial cultures isolated from the ground were described as the genera of Rhodococcus sp., Bacillus sp., Pseudomonas sp., and Acinetobacter sp. Protein complexes with endochitinase and exochitinase activities were purified from the culture liquid. These microorganisms can participate in chitin degradation in sea water. The average molecular weight of the protein fraction with the chitinolytic activity constituted 92–135 kDa. The ratio of the endo-/exochitinase activities of the enzymatic systems was increased in the order Pseudomonas sp. < Bacillus sp. < Acinetobacter sp. < Rhodococcus sp. 相似文献
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Elena G. Novoselova Vadim V. Novikov Sergey M. Lunin Olga V. Glushkova Tatyana V. Novoselova Svetlana B. Parfenyuk 《Electromagnetic biology and medicine》2019,38(1):74-83
We investigated the effects of weak combined magnetic fields (MFs) produced by superimposing a constant MF (in the range 30 - 150 µT) and an alternating MF (100 or 200 nT) on cytokine production in healthy Balb/C male mice exposed 2 h daily for 14 days. The alternating magnetic field was a sum of several frequencies (ranging from 2.5 - 17.5 Hz). The frequencies of the alternating magnetic field were calculated formally based on the cyclotron resonance of ions of free amino acids (glutamic and aspartic acids, arginine, lysine, histidine, and tyrosine). The selection of different intensity and frequency combinations of constant and alternating magnetic fields was performed to find the optimal characteristics for cytokine production stimulation in immune cells. MF with a constant component of 60 μT and an alternating component of 100 nT, which was a sum of six frequencies (from 5 to 7 Hz), was found to stimulate the production of tumor necrosis factor-α, interferon-gamma, interleukin-2, and interleukin-3 in healthy mouse cells and induce cytokine accumulation in blood plasma. Then, we studied the effect of this MF on tumor-bearing mice with solid tumors induced by Ehrlich ascite carcinoma cells by observing tumor development processes, including tumor size, mouse survival rate, and average lifespan. Tumor-bearing mice exposed to a combined constant magnetic field of 60 μT and an alternating magnetic field of 100 nT containing six frequencies showed a strong suppression of tumor growth with an increase in survival rate and enhancement of average lifespan. 相似文献
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David S. Duncan Lawrence G. Oates Ilya Gelfand Neville Millar G. Philip Robertson Randall D. Jackson 《Global Change Biology Bioenergy》2019,11(2):416-426
Nitrous oxide (N2O) is a potent greenhouse gas and major component of the net global warming potential of bioenergy feedstock cropping systems. Numerous environmental factors influence soil N2O production, making direct correlation difficult to any one factor of N2O fluxes under field conditions. We instead employed quantile regression to evaluate whether soil temperature, water‐filled pore space (WFPS), and concentrations of soil nitrate () and ammonium () determined upper bounds for soil N2O flux magnitudes. We collected data over 6 years from a range of bioenergy feedstock cropping systems including no‐till grain crops, perennial warm‐season grasses, hybrid poplar, and polycultures of tallgrass prairie species each with and without nitrogen (N) addition grown at two sites. The upper bounds for soil N2O fluxes had a significant and positive correlation with all four environmental factors, although relatively large fluxes were still possible at minimal values for nearly all factors. The correlation with was generally weaker, suggesting it is less important than in driving large fluxes. Quantile regression slopes were generally lower for unfertilized perennials than for other systems, but this may have resulted from a perpetual state of nitrogen limitation, which prevented other factors from being clear constraints. This framework suggests efforts to reduce concentrations of in the soil may be effective at reducing high‐intensity periods—”hot moments”—of N2O production. 相似文献
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Anna Filippova Irina Lyapina Ilya Kirov Victor Zgoda Alexey Belogurov Anna Kudriaeva Vadim Ivanov Igor Fesenko 《Journal of peptide science》2019,25(2)
Plant secretome comprises dozens of secreted proteins. However, little is known about the composition of the whole secreted peptide pools and the proteases responsible for the generation of the peptide pools. The majority of studies focus on target detection and characterization of specific plant peptide hormones. In this study, we performed a comprehensive analysis of the whole extracellular peptidome, using moss Physcomitrella patens as a model. Hundreds of modified and unmodified endogenous peptides that originated from functional and nonfunctional protein precursors were identified. The plant proteases responsible for shaping the pool of endogenous peptides were predicted. Salicylic acid (SA) influenced peptide production in the secretome. The proteasome activity was altered upon SA treatment, thereby influencing the composition of the peptide pools. These results shed more light on the role of proteases and posttranslational modification in the “active management” of the extracellular peptide pool in response to stress conditions. It also identifies a list of potential peptide hormones in the moss secretome for further analysis. 相似文献