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排序方式: 共有306条查询结果,搜索用时 15 毫秒
11.
EA Dukhanina TI Lukyanova EA Romanova V Guerriero NV Gnuchev GP Georgiev DV Yashin LP Sashchenko 《Cell cycle (Georgetown, Tex.)》2015,14(22):3635-3643
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response. 相似文献
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S. I. Tkachenko A. R. Mingaleev V. M. Romanova A. E. Ter-Oganes’yan T. A. Shelkovenko S. A. Pikuz 《Plasma Physics Reports》2009,35(9):734-753
Distribution of matter in the discharge channel formed upon a nanosecond electrical explosion of a single wire in air and vacuum was studied experimentally. Simultaneous use of optical, UV, and X-ray diagnostics made it possible to distinguish qualitatively different regions of the discharge channel, such as the current-carrying layers and the region occupied by a weakly conducting cold plasma. Several series of experiments with 25-μm-diameter 12-mm-long wires made of different materials were performed. The charging voltage and the current amplitude were varied in the ranges of U 0 = 10–20 kV and I max ∼ 5–10 kA, respectively. Explosion regimes with a current pause and with and without current interruption, as well as with wire preheating in air and vacuum, were studied. Shadow and schlieren images of the discharge channel were obtained using optical probing at the second harmonic of a YAG: Nd+3 laser (λ = 0.532 μm, τ ∼ 10 ns). In the experiments carried out in vacuum, X-ray images of the discharge channel were also obtained using an X-pinch as a point source of probing radiation and UV images were recorded using a four-frame MCP camera. 相似文献
14.
Markéta Ondračková Maria Yu Tkachenko Veronika Bartáková Anna Bryjová Michal Janáč Grzegorz Zięba Kacper Pyrzanowski Yuriy Kvach 《Journal of fish biology》2023,102(2):426-442
In Poland, distribution of non-native pumpkinseed Lepomis gibbosus (Centrarchidae) is strictly limited to the Oder river basin, where it was introduced in the early 20th century. Recently, several populations have been found in waterbodies adjacent to the Oder, particularly in its lower reaches. In this study, we compare the genetic relatedness of populations in the Oder basin with other European populations using nuclear (microsatellite) and mitochondrial (partial cytochrome c oxidase subunit I; cox1) markers. Microsatellite analysis indicated that four populations in the lower Oder form a separate cluster, while one in the middle Oder clustered with Danubian populations, from where probably having been introduced. Microsatellite data suggested that the lower Oder populations differ from other non-native European populations, making it impossible to estimate the source of introduction. Nevertheless, analysis of cox1 indicated that Oder pumpkinseeds belong to the same haplotype as the vast majority of European populations. Parasitological examination confirmed the presence of two North American species, the monogenean Onchocleidus dispar and trematode Posthodiplostomum centrarchi, in the lower Oder, both previously unknown in the region. Fifteen other parasite species were acquired, including glochidia of invasive Sinanodonta woodiana. In the middle Oder, parasite infection was more limited. Fish from the Gryfino Canal, considered one of the most invasive populations in Europe, showed the highest parasite abundance and diversity, and the highest somatic condition and growth rate due to warm water released from the Dolna Odra power plant. Our results highlight significant differences in somatic condition and parasite infection in long-established non-native pumpkinseed populations in the same river system, reflecting mainly environmental conditions. 相似文献
15.
Characteristic Features of EEG Spectral Characteristics in Persons with Deviant Sexual Behavior 总被引:1,自引:0,他引:1
The study was performed with participation of 59 right-handed men. The normal group consisted of 19 subjects, and 40 patients with organic brain lesions who had commited sexual offenses were divided into two groups: 19 patients with a diagnosis of paraphilia (pathology of sexual drive) made up the main test group, and 21 patients without such a diagnosis formed the control group. A monopolar EEG was recorded in 16 standard leads in the states of rest (eyes closed) and general activation (eyes open) and during presentation of cognitive tests. The following EEG features manifest in all the frequency ranges and functional states were revealed in the group of patients with paraphilias as compared to the control groups: a substantially increased level of interhemispheric coherence (ICoh) and increased spectral density in the posterotemporal area (T
5, T
6), a significantly decreased ICoh level between the F
3/4 and C
3/4 leads in the frontocentral area, and lower spectral densities in the leads Fp
2, C
4, and P
4. Analysis of reactions to loads presented showed that the general arousal in the group of patients with paraphilias was characterized by significantly greater shifts of EEG parameters associated with the desynchronization reaction (as compared to the control groups) and statistically significant disorders of interhemispheric interaction and EEG reactivity in the right hemisphere in the range during performance of a visuospatial (right-hemispheric) task. The results suggest the formation of a stationary activation focus in the right hemisphere with signs of involvement of the limbic structures in patients with paraphilias. 相似文献
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An exponential-phase culture of E. coli responded to the addition of H2O2 by a decrease in DNA supercoiling induced by the lowering of the energy status of cells, potassium leakage, and breaking of polynucleotide chains. Extending the time of exposure of E. coli cells to hydrogen peroxide led to an increase in the intracellular pools of putrescine and potassium, promotion of cellular energy status, and the restoration of DNA supercoiling to values much in excess of the prestress level. The subsequent stabilization of the intracellular putrescine pool was accompanied by a release of this polyamine from the cell. Based on these results and those available in the literature, a mechanism of E. coli adaptation to oxidative stress is suggested that assigns roles to putrescine, potassium, and cellular energy status. 相似文献
18.
Priit Adler Raivo Kolde Meelis Kull Aleksandr Tkachenko Hedi Peterson Jüri Reimand Jaak Vilo 《Genome biology》2009,10(12):R139-11
We present a web resource MEM (Multi-Experiment Matrix) for gene expression similarity searches across many datasets. MEM
features large collections of microarray datasets and utilizes rank aggregation to merge information from different datasets
into a single global ordering with simultaneous statistical significance estimation. Unique features of MEM include automatic
detection, characterization and visualization of datasets that includes the strongest coexpression patterns. MEM is freely
available at . 相似文献
19.
Iu I Bazhenov A Soodanbekova E Ia Tkachenko M A Iakimenko 《Biulleten' eksperimental'no? biologii i meditsiny》1978,85(3):259-260
The authors studied the working capacity and heat formation of the skeletal muscles during contraction in rats--control and those adapted to hypoxia. The force of contraction, the work and fatigueability of the muscles, as well as elevation of the muscle temperature as a result of contraction were determined under conditions of indirect muscle electrostimulation. Hypoxia adaptation failed to influence the force of muscle contraction and the work performed. However, hypoxia led to reduction of the temperature effect of the muscle contraction per unit of the work performed. This pointed to increase of the efficiency of the muscle work in hypoxia adaptation. Fatigueability of the muscles in "hypoxic" rats was elevated. Changes in the energy of the muscle contraction in hypoxia and cold adaptation were different. 相似文献
20.
Application of 1% methol, which, along with cold, activates specific thermosensitive ionic channels, changes the number of functioning cold receptors on the skin of the forearm similarly to the cold exposure test; however, it does not affect the number of heat receptors and does not significantly change the threshold of cold sensation. Group variants of responses to menthol that indicate individual differences in the sensitivity of skin receptors to the effects of methol and cold have been found. The results obtained give grounds to suggest that, from the variant of response to menthol (a decrease, increase, or absence of changes in the number of functioning cold receptors 5 min after menthol application), it is possible to predict specific features of response to cold. 相似文献