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Catch per unit effort (CPUE), length, weight and maturity data for Clarias gariepinus were collected during monthly gillnet surveys in the upper Okavango Delta between 2001 and 2009 to investigate their relationship with the annual flood-pulse. CPUE, condition factor (K) and the proportion of ripe-running fish (PRR) in the population followed a unimodal annual cycle that could be modelled using water temperature and flood-pulse hydrology. Increased CPUE during declining water levels was most likely a result of feeding migrations and aggregation behaviour. The observed increase in K during low floods in October and November preceded the increase in PRR, which increased mainly with increasing temperature but appeared less dependent on flow. This study provided quantitative evidence that the biology of fish in the Okavango Delta is mainly dependent on the annual flood regime and, therefore, that conservation efforts should be focused on maintaining natural flow patterns in the face of climate change and potential water extraction schemes upstream. 相似文献
3.
Biology Bulletin - In vivarium conditions, the growth and attainment of puberty of the offspring of constant parental pairs have been studied in relation to the calendar month of birth (May or... 相似文献
4.
O. B. Vasilyeva M. A. Nazarova P. O. Ripatti N. N. Nemova 《Contemporary Problems of Ecology》2016,9(2):177-187
We studied the growth performance and lipid composition of liver, muscles and visceral fat in rainbow trout Parasalmo mykiss (Walbaum, 1792) and the diets used in its cultivation during the spring-summer season. The differences in dietary lipid composition determined modifications in the biochemical composition of tissues of rainbow trout and had an effect on the weight and growth rate of the fish. Trophic and seasonal factors also had their influence on the studied parameters. The degree of influence depended on the functional characteristics of tissues and organs of rainbow trout. 相似文献
5.
V. M. Nazarova 《Paleontological Journal》2016,50(5):480-484
Distribution of the Devonian conodont genus Pelekysgnathus is considered. A new species, P. jeppssoni sp. nov. from the Mosolovian Regional Stage (Middle Devonian, Eifelian) of the Voronezh Anteclise is described. 相似文献
6.
E. V. Borvinskaya I. V. Sukhovskaya A. A. Kochneva O. B. Vasilyeva M. A. Nazarova L. P. Smirnov N. N. Nemova 《Contemporary Problems of Ecology》2016,9(2):195-202
The base levels and seasonal variability of ethoxyresorufin-O-deethylase (EROD) activity, glutathione-S-transferase (GST) activity, reduced glutathione concentration (GSH) and phospholipids concentration (PhL) of Coregonus lavaretus (Linnaeus, 1758) and Coregonus muksun (Pallas, 1814) were investigated. The relationships between this biochemical markers, hepatosomatic index and seasonal growth were also examined. 相似文献
7.
To improve the quality of diagnostics and treatment of patients with immunodeficient states, two groups of patients were examined for the presence of cytomegalovirus (CMV) infection, among them 1,348--with clinical manifestations of CMV infection (group 1) and 335 hematological patients (group 2); in addition, 36 patients with secondary immunodeficiency and 31 patients with aplastic and hemolytic anemia, or with anemia of unclear origin were examined for the presence of parvovirusinfection (B19). The results of enzyme immunoassay, polymerase chain reaction and immunofluorescence tests active CMV infection, confirmed by determination of IgM, low avidity IgG, antigen and DNAemia, was registered in group 2 more often than in group 1. Examinations on the presence of parvovirus infection revealed that in anemia patients with the low level of IgG or its absence IgM was also detected more often than in group 1. In mixed infection caused by CMV and parvovirus B19 the disease took a more severe course than in monoinfection, which was probably due to the parallel action exerted by parvovirus on erythrocyte production in hematopoiesis and by CMV on the monocytic and macrophagal row of cell. 相似文献
8.
Feofanov AV Nazarova AI Karmakova TA Pliutinskaia AD Grishin AI Iakubovskaia RI Lebedeva VS Ruziev RD Mironov AF Maurizot JC Vigny P 《Bioorganicheskaia khimiia》2004,30(4):417-428
Lipophilic derivatives of chlorin p6, 13,15-N-(carboxymethyl)cycloimide methyl ester (CIC1) and 13,15-N-(2-carboxyethyl)cycloimide methyl ester (CIC2), were shown to absorb light in 710 nm region and to be efficient IR photosensitizers. They exhibit similar phototoxicities on the cells of A549 human lung adenocarcinoma, which are 40- and 100-fold higher than those of chlorin p6 and the clinically used Photogem, respectively, and are not toxic in the absence of light irradiation. The confocal spectral imaging technique allowed us to demonstrate that the high phototoxicity of CIC1 and CIC2 is due to their ability to readily penetrate to cells and to be bound to the cell membranes and lipid-containing structures in the monomeric photoactive form. Under the irradiation, the membrane-bound CIC1 and CIC2 are characterized by high quantum yields of singlet oxygen generation (0.6 and 0.65, respectively) and the inability to produce hydroxyl radicals. A 1.5-microM content of CIC1 and CIC2 in the incubation medium provides for their average cytoplasmic concentrations of 21 and 16.5 microM, respectively. The incubation times to achieve 50% level of maximum accumulation for CIC1 and CIC2 in A549 cells are 30 +/- 6 and 24 +/- 12 min, and the times for 50% release of the dyes from the cells are 17 +/- 4 and 50 +/- 10 min, respectively. A diffuse distribution with the predominant accumulation in the membranes of the Golgi apparatus and mitochondria is characteristic of both CIC2 and CIC1, whereas, in addition, CIC1 is considerably accumulated in lipid droplets (cellular organelles responsible for the storage and metabolism of neutral lipids and steryl esters). Our results demonstrate that changes in the structure of the imide substituent could affect the intracellular localization and the rate of release of chlorin p6 cycloimide derivatives from cells while preserving their high photodynamic activity. 相似文献
9.
Onishchenko GG Kovalev NG Koval'chuk IV Balaban OA Nazarova EO Sirotkina SA 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2003,(6):116-119
As the result of the high flood, an increase in the area of anopheligenic water reservoirs occurred on the inundated territories, which created favorable conditions for the proliferation of Anopheles mosquitoes, the vectors of malarial plasmodia, thus creating the threat of the formation of the local sources of malaria in case of its penetration from other regions unfavorable with respect to this disease. In the affected towns and regions hydrotechnical measures aimed at decreasing the surface of anopheligenic water reservoirs, as well as measures aimed at the decrease in the number of the larval and imaginal stages in the development of mosquitoes, were taken, which made it possible to prevent the probable epidemiological aggravations in malaria. 相似文献
10.
Genetic distances of 18 Finnish-Ugric and other populations of Europe, Asia and America by 28 alleles of 12 loci of proteins, enzymes and blood groups were calculated. The data of matrix of genetic distances and dendrogramme constructed by paired clusterisation method suggested that there was the relationship of Finnish-Ugric populations and some Caucasoids and North Mongoloid populations. These data give new approaches to the problem of Finnish-Ugric phylogenesis. 相似文献