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61.
Phylogeography of southern Asian Dolly Varden char was studied using the data on mtDNA variation (regions ND1/ND2, ND5/ND6,
and Cytb/D loop) obtained using PCR-RFLP analysis. Analysis of contemporary population genetic structure showed that Salvelinus malma krascheninnikovi throughout the whole species range was characterized by high population differentiation in combination with rather small
differences between the populations from remote regions. The genealogy of mtDNA haplotypes was reconstructed and nested clade
analysis of geographical distances was performed. Geographical distribution of mtDNA haplotypes of S. m. krascheninnikovi was explained by population genetic processes (restricted gene flow), as well as by historical demographic events (range
expansion and fragmentation). It was demonstrated that the main demographic events were associated with cyclic processes of
the geological formation of the Sea of Japan and adjacent territories. Furthermore, genealogical tree of S. m. krascheninnikovi contained the traces of secondary contact between isolated phylogeographical lineages. 相似文献
62.
N. F. Kushnerova S. E. Fomenko V. G. Sprygin T. V. Kushnerova Yu. S. Khotimchenko E. V. Kondrat’eva L. A. Drugova 《Russian Journal of Marine Biology》2010,36(3):209-214
It was shown in rats that stress is accompanied by a decrease in osmotic resistance and antioxidant protection of erythrocytes
and an increase in their volume and diameter; cholesterol esters were reduced, the amounts of malone dialdehyde, cholesterol,
sphingomyelin, and phospholipid lysofractions were increased. Comparative data on the membrane protecting activity of extracts
of Laminaria japonica and Eleutherococcus senticosus are presented. Administration of these extracts caused the normalization of the parameters of erythrocytes in rats. 相似文献
63.
V. V. Kasyan 《Russian Journal of Marine Biology》2010,36(3):167-175
Ballast water samples were taken from three ships that arrived at the Port of Vladivostok (Peter the Great Bay, Sea of Japan)
from ports of Japan (Sea of Japan and Pacific Ocean) and China (Yellow Sea and Yangtze River). The holoplankton in samples
was presented by seven taxonomic groups, among which copepods (subclass Copepoda, 33 species) and cladocerans (subclass Cladocera,
5 species) dominated. In the samples, eight nonindigenous copepod species were revealed. The information contained in this
paper may be of importance for the assessment of the risk of subsequent invasion of new species and the development of techniques
for monitoring the qualitative and quantitative structures of ballast water. 相似文献
64.
Field observations on colonies of seagulls (Laridae) were carried out annually on islands of the northern Tatar Strait during
2001–2008. A general tendency towards a reduction in the number of nesting birds was observed on all islands surveyed. The
anxiety factor and direct destruction of bird eggs and fledglings caused the whole or the greater part of colony to migrate
to “quieter” sites on islands or the continental coast. The replacement of Larus crassirostris by L. schistisagus was observed in sites where the two species nest in neighborhood. Nesting specimens of L. schistisagus were found on islands of Lake Bolshoe Kizi, suggesting that the birds are in search of alternative nesting places that are
less accessible to humans and predators. 相似文献
65.
E. V. Shamshurina M. G. Eliseikina I. Yu. Petrova A. A. Bulgakov 《Russian Journal of Marine Biology》2010,36(4):293-299
This study revealed a new lectin (MBL-SN) in the coelomic fluid of the sea urchin Strongylocentrotus nudus. Based on the peculiarities of molecular structure and carbohydrate specificity, MBL-SN can be assigned to the mannan-binding
lectin family. Using polyclonal monospecific rabbit antibodies against MBL-SN, the presence of MBL-SN in the sea urchin was
detected in two forms: a soluble form dissolved in the coelomic fluid and an extracellular matrix-bound form. The biosynthesis
site of this lectin may be one of the subpopulations of morula cells-coelomic fluid cells that perform heterosynthesis. Our
results demonstrate the similarity of the sea urchin lectin MBL-SN to the previously investigated MBLs of the holothurians
Cucumaria japonica and Apostichopus japonicus, and suggest a similarity to MBLs of vertebrates, which also have soluble and bound forms. 相似文献
66.
Stanislava V. Avrova Yurii S. Borovikov 《Biochemical and biophysical research communications》2010,394(1):126-65
A new evidence on the regulatory function of twitchin, a titin-like protein of molluscan muscles, at muscle contraction has been obtained at studying the movements of IAF-labeled mussel tropomyosin in skeletal ghost fibers during the ATP hydrolysis cycle simulated using nucleotides and non-hydrolysable ATP analogs. For the first time, myosin-induced multistep changes in mobility and in the position of mussel tropomyosin strands on the surface of the thin filament during the ATP hydrolysis cycle have been demonstrated directly. Unphosphorylated twitchin shifts the tropomyosin towards the position typical for muscle relaxation, decreases the tropomyosin affinity to actin and inhibits its movements during the ATPase cycle. Phosphorylation of twitchin by the catalytic subunit of protein kinase A reverses this effect. These data imply that twitchin is a thin filament regulator that controls actin-myosin interaction by “freezing” tropomyosin in the blocked position, resulting in the inhibition of the transformation of weak-binding states into strong-binding ones during ATPase cycle. 相似文献
67.
Vl. A. Brykov N. Polyakova L. A. Skurikhina A. D. Kukhlevsky O. N. Kirillova D. Churikov †‡ A. I. Pudovkin A. J. Gharrett † 《Journal of fish biology》1999,55(3):617-635
Both odd- and even-year pink salmon populations were sampled during the spawning runs in Firsovka and Bakhura rivers on Sakhalin Island. Four collections of 30 fish spaced at 2-week intervals were taken from each river in 2 consecutive years. Four restriction endonucleases were used to examine 2·15% of the mitochondrial genome. Eighteen variable sites and three types of insertion defined 37 haplotypes among 449 fish. Heterogeneity tests showed highly significant differences among temporal collections taken in the odd year from Bakhura River, and no significant differences among temporal collections from the other three spawning runs. However, probabilities of homogeneity among temporal collections were low in all tests, and an integral estimate of the probability of homogeneity for the total set of tests was less than 0·001, indicating highly significant overall temporal heterogeneity. Analysis of molecular variance (AMOVA), revealed that a small portion of the variance was distributed among temporal collections, and small φST values that differed significantly from zero only in the odd-year population in Bakhura River. Temporal differences in spawning are probably adapative, and allow greater productivity in areas of high spawning densities. 相似文献
68.
Yu. A. Reunova N. A. Aizdaicher N. K. Khristoforova A. A. Reunov 《Russian Journal of Marine Biology》2007,33(3):166-172
The effects of selenium (0.01, 0.5, 1, 5 and 10 mg/liter) on the growth and ultrastructure of the microalga Dunaliella salina were investigated following its transfer into clean water. Selenium concentrations of 5 and 10 mg/liter were toxic to D. salina, and reinoculation of microalga into clean water did not prevent it from total mortality. When reinoculated from medium with 0.01 mg Se/liter, the cell population density of D. salina was restored in 14 days. The number of ultrastructural alterations in cells was the same as in the control, while the excretory activity of microalga between days 4 and 10 of this experiment was higher. Cell population growth of D. salina transferred from 0.5 and 1 mg Se/liter was lower than in the control. No ultrastructural defects were observed in microalga reinoculated from medium with a selenium concentration of 0.5 mg/liter and the excretion level corresponded to that at 0.01 mg/liter. Various types of ultrastructural damage were found in microalga from medium with 1 mg Se/liter, which was previously reported to be threshold for D. salina; however, the number of cell injuries decreased with increasing time in clean medium. Excretory activity was decreased at the beginning of experiment; but after 7 days, it was restored to the control level. Though there were no ultrastructural alterations in microalgal cells from medium with 0.5 mg Se/liter, we assume that they had molecular defects that could inhibit the cell population growth. The study of microalgae following their reinoculation from medium containing toxicants into clean medium can be a useful method for evaluating algal survival after toxic exposure. 相似文献
69.
O. V. Chernikov I. V. Chikalovets V. I. Molchanova M. A. Pavlova P. A. Lukyanov 《Russian Journal of Marine Biology》2007,33(5):329-332
Algae of Peter the Great Bay (Sea of Japan) were for the first time bioassayed as a source of lectins. From 28 algal species of three orders, only some extracts from brown (Phaeophyta) and red (Rhodophyta) seaweeds were found to cause agglutination of human erythrocytes. The hemagglutinating activity of extracts from three species of brown algae and the red alga Tichocarpus crinitus was caused by lectins; for a majority of extracts from the investigated algae, this activity was due to the presence of substances of non-lectin nature. 相似文献
70.
The effects of pectin from the eelgrass Zostera marina on toxic liver injury induced by enteral administration of lead acetate are examined in experiments on rats. The results show that pectin helps to rapidly reduce lead concentration in liver, to decrease lipid peroxidation, and to normalize the levels of total cholesterol and triglycerides in blood serum and liver. 相似文献