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排序方式: 共有208条查询结果,搜索用时 15 毫秒
1.
L V Filev S F Enokhin N N Kotsiubinski? D I Korotkov B G Liparteliani 《Tsitologiia》1988,30(4):466-470
10 healthy men underwent a 48 hour acute hypobaric hypoxia in the "Taba?" climate chamber imitating conditions of an altitude of 4.00 m. above s.l. The "ascent" and "descent" took 30 minutes each. Blood and bone marrow samples were taken before entering the chamber and immediately after leaving it. A decrease in colony-forming capacity of granulo- and monocyte and fibroblast precursors was shown, along with an increase in functional activity of circulating monocytes and monocyte precursors in bone marrow. A possible role of changes in granulo- and monocytopoiesis and in stromal cells is discussed in relation to the increased morbidity and decreased cicatricial and bone tissue reparation in the mountains. 相似文献
2.
The concept of nucleic acid sequence base alternations is presented.The number of base alterations for the sequences of differentlength is established. The definition of "enlarged similarity"of nucleic acids sequences on the basis of sequence base alterationsis introduced. Mutual information between sequences is usedas a quantitative measure of enlarged similarity for two comparedsequences. The method of mutual information calculation is developedconsidering the correlation of bases in compared sequences.The definitions of correlated similarity and evolution similaritybetween compared sequences are given. Results of the use ofenlarged similarity approach for DNA sequences analysis arediscussed. 相似文献
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Pamela McElwee Katherine Calvin Donovan Campbell Francesco Cherubini Giacomo Grassi Vladimir Korotkov Anh Le Hoang Shuaib Lwasa Johnson Nkem Ephraim Nkonya Nobuko Saigusa Jean‐Francois Soussana Miguel Angel Taboada Frances Manning Dorothy Nampanzira Pete Smith 《Global Change Biology》2020,26(9):4691-4721
Interlocked challenges of climate change, biodiversity loss, and land degradation require transformative interventions in the land management and food production sectors to reduce carbon emissions, strengthen adaptive capacity, and increase food security. However, deciding which interventions to pursue and understanding their relative co‐benefits with and trade‐offs against different social and environmental goals have been difficult without comparisons across a range of possible actions. This study examined 40 different options, implemented through land management, value chains, or risk management, for their relative impacts across 18 Nature's Contributions to People (NCPs) and the 17 Sustainable Development Goals (SDGs). We find that a relatively small number of interventions show positive synergies with both SDGs and NCPs with no significant adverse trade‐offs; these include improved cropland management, improved grazing land management, improved livestock management, agroforestry, integrated water management, increased soil organic carbon content, reduced soil erosion, salinization, and compaction, fire management, reduced landslides and hazards, reduced pollution, reduced post‐harvest losses, improved energy use in food systems, and disaster risk management. Several interventions show potentially significant negative impacts on both SDGs and NCPs; these include bioenergy and bioenergy with carbon capture and storage, afforestation, and some risk sharing measures, like commercial crop insurance. Our results demonstrate that a better understanding of co‐benefits and trade‐offs of different policy approaches can help decision‐makers choose the more effective, or at the very minimum, more benign interventions for implementation. 相似文献
5.
AB Zarafi AM Emechebe AD Akpa O Alabi 《Archives Of Phytopathology And Plant Protection》2013,46(4):261-268
Pearl millet downy mildew (DM) incidence, severity and yield losses of two pearl millet varieties (local and improved) due to the disease were determined in the field. Significant differences in the disease incidence and severity were recorded in the plots sown with metalaxyl-treated seeds and those sown with non-treated seeds, indicating the efficacy of the fungicide on the fungus. Yield losses due to non-treatment of seeds with metalaxyl was 40.88 and 45.39% in a local variety and 43.00 and 18.60% in an improved variety in the 2000 and 2001 cropping seasons respectively. Significant differences between plots sown with metalaxyl-treated and those sown with non-treated seeds were obtained for other yield components such as 1000-grains weight, panicle length and weight. 相似文献
6.
M. V. Kireev N. S. Medvedeva A. D. Korotkov Ju. I. Polyakov A. D. Anichkov S. V. Medvedev 《Human physiology》2013,39(1):54-57
In this article, the characteristics of the functional activity of the anterior cingulate cortex (ACC), a key element of the neuroanatomical error detection system of the brain in drug-resistant forms of obsessive-compulsive disorder (OCD) are discussed on the basis of both original and published data. Available data indicate the presence of a functional deficit zone in the ACC during PCD. This fact suggests that the functions of the ACC in OCD patients are partially redistributed between other brain areas. Thus, in contrast to the previously accepted ideas, the target of stereotactic surgery for OCD is a pathologically altered brain region. Probably, this explains the fact that the operation does not lead to significant changes in the patient’s psyche. The pathological reorganization of the functional activity of the brain in OCD remains unclear and requires further investigation. 相似文献
7.
S. M. Korotkov K. V. Sobol I. V. Shemarova V. V. Furaev A. R. Shumakov V. P. Nesterov 《Biophysics》2016,61(5):733-740
The inotropic effect of Pr3+ and La3+ ions on the heart muscle of frog Rana ridibunda, as well as the influence of the ions on respiration, swelling, and the potential (ΔΨmito) on the inner membrane of Ca2+- loaded rat heart mitochondria, energized by glutamate and malate or succinate in the presence of rotenone were studied. It was found that 2 mM Pr3+ in Ringer’s solution reduces the force of spontaneous contractions and those induced by electrical stimulation in the heart; it had a negative chronotropic effect, decreasing the frequency of spontaneous contractions. Pr3+ and La3+ prevented a decrease in the 2,4-dinitrophenol (DNP)- uncoupled respiration of energized rat heart mitochondria, swelling of these organelles in salt media, and a reduction in ΔΨmito on the inner mitochondrial membrane that were induced by Ca2+ ions. Retardation by Pr3+ and La3+ ions of these calcium-induced effects may suggest that in the inner mitochondrial membrane these metals inhibit the opening of the mitochondrial permeability transition pore caused by Ca2+ overload of mitochondria. The data we obtained are important for a better understanding of the mechanisms of the damaging action of rare-earth elements on Ca2+-dependent processes in the vertebrate myocardium. 相似文献
8.
Background
Organisms are capable of developing different phenotypes by altering the genes they express. This phenotypic plasticity provides a means for species to respond effectively to environmental conditions. One of the most dramatic examples of phenotypic plasticity occurs in the highly social hymenopteran insects (ants, social bees, and social wasps), where distinct castes and sexes all arise from the same genes. To elucidate how variation in patterns of gene expression affects phenotypic variation, we conducted a study to simultaneously address the influence of developmental stage, sex, and caste on patterns of gene expression in Vespula wasps. Furthermore, we compared the patterns found in this species to those found in other taxa in order to investigate how variation in gene expression leads to phenotypic evolution. 相似文献9.
10.
Biophysics - Abstract—A new data bank containing potential reading frame shifts was developed. A new mathematical method based on the use of the genetic algorithm and dynamic programming was... 相似文献