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The impact of a biologically active food supplement containing salmon milt DNA on cellular immunity was experimentally studied. It was shown that the DNA had a dose-dependent stimulating effect on lymphocyte transformation, stimulated the DTH response and protected from experimental listeriosis infection.  相似文献   
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The western Bering Sea is an important region that is used by many nekton species for feeding. From the seasonal aspect, these waters are characterized by pronounced dynamics of the abundance and structure of the nekton community. The pattern of seasonal variations in the total biomass, composition, and structure of nekton in the upper epipelagic layer (0–50 m) of this region are considered based on the data of the complex studies conducted by the Pacific Research Fisheries Center (TINRO Center) in the deep-sea basins of the western Bering Sea and the Navarin area in June–October, 2003–2015. During June–October, the total nekton biomass changed by more than an order of magnitude: from 100 kg/km2 in early June it increased to a maximum of 2700 kg/km2 in the middle of August and then declined significantly, to 200 kg/km2, in late October. The major contribution to the nekton biomass was made by Pacific salmon (Oncorhynchus spp.), mainly O. keta, as well as by the boreopacific gonate squid (Boreoteuthis borealis) and the shortarm gonate squid (Gonatus kamtschaticus). As well, walleye pollock (Theragra chalcogramma), Pacific herring (Clupea pallasii), and capelin (Mallotus villosus) were abundant in waters near the shelf. The dynamics of the species structure can be divided into three periods: (1) early summer, from June to the second 10 days of July, when pre-anadromous pink (O. gorbuscha) and chum salmon predominate and the species diversity is at a medium level (the polydominance index is 3.5–4.0); (2) summer, from the third 10 days of July to the second 10 days of September, when chum salmon becomes dominant (more than 70% of the biomass) and the species diversity is at a minimum (1.5–2.0); and (3) autumn, from the third 10 days of September to October, when common species such as chum salmon, sockeye salmon, and boreopacific gonate squid have relatively equal proportions, the proportion of pink salmon underyearlings is also high, and the species diversity is at a maximum (4.5). The pattern of the spatial distribution in the early summer period is characterized by active formation of the nekton community due to the large-scale migrations from the central and eastern Bering Sea and from the Pacific Ocean. In the summer period, the concentration of the nekton in the western Bering Sea, particularly in the Aleutian Basin, reaches the maximum level and the migratory activity decreases. Reverse migration processes are observed in the autumn period: a major portion of the nekton biomass redistributes to the southeastern Commander Basin for further movement to the ocean and the central Bering Sea.  相似文献   
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Microvesicles were isolated from blood plasma and total blood of healthy females and breast cancer patients by filtration and ultracentrifugation. According to flow cytometry, different subpopulations of exosomes were represented in blood of healthy donors and cancer patients at different levels with median fluorescence intensity (MFI) values in both groups arranged in the following order: CD24/СD9 > СD9/СD81 > CD9/CD63 = CD24/CD63. Concentration of exosomes in blood plasma of healthy females estimated by nanoparticle tracking analysis (NTA) did not exceed (3.71 ± 1.15) × 107 particles/mL of blood and did not differ from that in plasma of breast cancer patients, which averaged (3.99 ± 1.03) × 107 particles/mL of blood. Concentration of total exosomes in blood (including exosomes from plasma and blood cell surface-bound exosomes) did not depend on the presence/absence of a tumor; the values were (7.66 ± 0.7) × 107 particles/mL of healthy blood and (9.4 ± 1.24) × 107 particles/mL of blood from cancer patients. Comparative analysis of exosomes using 2-D electrophoresis with subsequent analysis of 2-D proteomic maps revealed proteins missing in blood or differentially expressed in healthy females and breast cancer women. The data presented provide the possibility for identification of exosomal proteomic markers and isolation of tumor-specific exosomes, which contributes to the development of breast cancer diagnostics.  相似文献   
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Penaeid and carid communities were assessed in St Lucia over a wide range of saline conditions, water level conditions and mouth states, including a six-month marine connection and various connections to the Mfolozi Estuary. Samples were collected biannually in spring and autumn from November 2004 to May 2012 using seine nets. Seven penaeid and seven carid species were recorded, of which Palaemon pacificus, P. peringueyi, Penaeus indicus and Metapenaeus monoceros were the most abundant. The decline from 2004 to 2007 in both species recorded and densities of freshwater, estuarine and marine species during the initial closed period was linked to increased salinity, lack of recruitment and reduced estuarine surface area. Increased wave action and high seas following Cyclone Gamede opened the mouth in March 2007 after a 57-month closed period, resulting in recruitment of marine species, predominantly P. indicus, followed by a decline in densities after reclosure in August 2007. Increases in marine and freshwater species were evident after Mfolozi flood connections during 2008, 2009 and 2010. Highest densities were recorded after breaching in 2007 and after flood connections, highlighting the importance of a marine link to maintain the recruitment of penaeid species.  相似文献   
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Cytokinin oxidase (EC 1.5.99.12) is an enzyme that catalyzes the irreversible degradation of cytokinin phytohormones that are extremely necessary for growth, development, and differentiation of plants. Cytokinin oxidase plays an important role in the regulation of quantitative level of cytokinins and their distribution in plant tissues. This review generalizes the available information on the structure, properties, and functional role of this enzyme in plant ontogeny under conditions of normal growth and under the influence of unfavorable environmental factors.  相似文献   
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