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21.
A. A. Khoruzhiy A. V. Zavolokin A. N. Starovoytov S. V. Naydenko N. S. Vanin E. N. Dubovets E. A. Kornilova P. O. Emelin A. A. Somov 《Russian Journal of Marine Biology》2013,39(7):486-500
According to the data of trawl catches performed by the R/V “TINRO” in the upper epipelagic zone (0–50 m) of Pacific waters off the Kuril Islands from June 2 to July 8, 2012, the abundance of nekton was the lowest for the recent 9 years; thus, its density in 2012 (1.5 t/km2) was lower than the average value for the 2004–2012 period (2.40 ± 0.39 t/km2). The major portion of the nekton biomass was formed by pacific salmon (706 000 tons, or 43.6%); their role grows abruptly during pre-spawning migrations of pink salmon, whose proportion reached 29.8% (483 000 t). In 2012, the recorded biomass of pre-anadromous pink salmon was as high as those in the previous 3 years, and even higher than the estimate of 2010 (479 800 t), which is the largest value for even-numbered years. The value of 2012 also was comparable with the estimates for the previous odd-numbered year, 2011, when the total biomass of the species constituted 496 500 t. Chum salmon stands out among other salmon for its record-high biomass (192 700 t, 11.9%), which was twice as high as that in 2011. The biomass and the share of the mesopelagic fish complex was the lowest (286800 t, 17.7%) since 2004. Among other fish species, Kuril groups of walleye pollock also had a substantial biomass (381 200 t, 23.5%). The total biomass of squid (225 300 t, 13.9%) was lower than the value of 2011 (326 300 t, 14.8%) owing to the decline in the biomass of Boreopacific gonate squid by 90 000 t. 相似文献
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Radchenko V. I. Kanzeparova A. N. Somov A. A. Grigorov I. V. 《Russian Journal of Marine Biology》2021,47(7):534-547
Russian Journal of Marine Biology - The distribution and abundance of four common myctophid fish species in the upper epipelagic layer of the northeastern North Pacific in winter were analyzed... 相似文献
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In vertebrates and the cephalochordate, amphioxus, the closest vertebrate
relative, Hox genes are linked in a single cluster. Accompanying the
emergence of higher vertebrates, the Hox gene cluster duplicated in either
a single step or multiple steps, resulting in the four-cluster state
present in teleosts and tetrapods. Mammalian Hox clusters (designated A, B,
C, and D) extend over 100 kb and are located on four different chromosomes.
Reconstructing the history of the duplications and its relation to
vertebrate evolution has been problematic due to the lack of alignable
sequence information. In this study, the problem was approached by
conducting a statistical analysis of sequences from the fibrillar-type
collagens (I, II, III, and IV), genes closely linked to each Hox cluster
which likely share the same duplication history as the Hox genes. We find
statistical support for the hypothesis that the cluster duplication
occurred as multiple distinct events and that the four-cluster situation
arose by a three- step sequential process.
相似文献
26.
The alcohol dehydrogenase (Adh) gene was isolated from Drosophila simulans
and D. mauritiana, and the DNA sequence of a 4.6-kb region, containing the
structural gene and flanking sequence, was determined for each. These
sequences were compared with the Adh region of D. melanogaster to
characterize changes that occur in the Drosophila genome during evolution
and to identify conserved sequences of functional importance. Drosophila
simulans and D. mauritiana Adh are organized in a manner similar to that of
D. melanogaster Adh, including the presence of two promoters for the single
Adh gene. This study identified conserved flanking elements that, in
conjunction with other studies, suggest regions that may be involved in the
control of Adh expression. Inter- and intraspecies comparisons revealed
differences in the kinds of sequence changes that have accumulated.
Sequence divergence in and around the Adh gene was used to assess inter-
and intraspecies evolutionary relationships. Finally, there appears to be
an unrelated structural gene located directly 3' of the Adh transcribed
region.
相似文献
27.
Central CCL2 signaling onto MCH neurons mediates metabolic and behavioral adaptation to inflammation 下载免费PDF全文
Ophélia Le Thuc Céline Cansell Miled Bourourou Raphaël GP Denis Katharina Stobbe Nadège Devaux Alice Guyon Julie Cazareth Catherine Heurteaux William Rostène Serge Luquet Jean‐Louis Nahon Carole Rovère 《EMBO reports》2016,17(12):1738-1752
Sickness behavior defines the endocrine, autonomic, behavioral, and metabolic responses associated with infection. While inflammatory responses were suggested to be instrumental in the loss of appetite and body weight, the molecular underpinning remains unknown. Here, we show that systemic or central lipopolysaccharide (LPS) injection results in specific hypothalamic changes characterized by a precocious increase in the chemokine ligand 2 (CCL2) followed by an increase in pro‐inflammatory cytokines and a decrease in the orexigenic neuropeptide melanin‐concentrating hormone (MCH). We therefore hypothesized that CCL2 could be the central relay for the loss in body weight induced by the inflammatory signal LPS. We find that central delivery of CCL2 promotes neuroinflammation and the decrease in MCH and body weight. MCH neurons express CCL2 receptor and respond to CCL2 by decreasing both electrical activity and MCH release. Pharmacological or genetic inhibition of CCL2 signaling opposes the response to LPS at both molecular and physiologic levels. We conclude that CCL2 signaling onto MCH neurons represents a core mechanism that relays peripheral inflammation to sickness behavior. 相似文献
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N N Besednova G P Somov 《Journal of hygiene, epidemiology, microbiology, and immunology》1982,26(3):235-241
Integral evaluation of some humoral and cellular immunity factors in patients with pseudotuberculosis (Far-East scarlatinoid fever) with varying severity of its course was carried out. Inadequate immune reaction of human organism in response to infection with pseudotuberculosis was established at the level of both specific (sporadic cases of lacking synthesis or poor synthesis of IgM antibodies, lacking synthesis of IgG antibodies) and non-specific factors (incomplete phagocytic reaction). Phagocytosis is higher in monocytes than in neutrophils during pseudotuberculosis. The opsonizing properties of blood serum, the intensity of which increases in the course of disease, are great importance in freeing the organism from bacteria of pseudotuberculosis. The most rapid and technically simplest is the determination of antibodies in blood serum of the patients by means of the reaction of indirect hemagglutination. For this purpose the authors developed a new, highly sensitive, and specific preparation - the dry erythrocyte antigenic diagnostic agent. 相似文献
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The specific activity of urease, nitrogenase, hialuronidase and neuraminidase in Y. pseudotuberculosis grown in different culture media and at different temperature has been studied. These enzymes have been found capable of functioning at both relatively low (2-8 degrees C) and high (37 degrees C) temperatures. The thermoadaptive properties of Y. pseudotuberculosis within a wide range of temperatures are ensured by the constant presence of isoenzymes, functioning only at low temperatures or only at high temperatures, in the microbial cells. Low temperature in combination with a definite culture medium triggers the activity of certain enzymatic systems, which explains, to some extent, the biochemical mechanisms of the psychrophilic properties of Y. pseudotuberculosis. 相似文献