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21.
Kolmakov VI 《Mikrobiologiia》2006,75(2):149-153
Methods for prevention of mass development of the cyanobacterium Microcystis aeruginosa Kutz emend. Elenk. in continental water bodies and industrial water supply systems are reviewed. The physicochemical, chemical, and biological methods for prevention of M. aeruginosa development in water bodies and water supply systems are considered; examples of successful inhibition of M. aeruginosa growth in laboratory experiments are demonstrated. The scientific problems are outlined that are to be solved for perfecting techniques for prevention of M. aeruginosa mass development in open water bodies and in closed water supply systems.  相似文献   
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Unmanned aircraft systems (UAS) are remote‐controlled devices capable of collecting information from difficult‐to‐access places while minimizing disturbance. Although UAS are increasingly used in many research disciplines, their application to wildlife research remains to be explored in depth. Here, we report on the use of a small UAS to monitor temporal changes in breeding population size in a Black‐headed Gull Chroicocephalus ridibundus colony. This method makes it possible to obtain georeferenced data on nest locations without causing colony disturbance, which would not otherwise be possible via direct ground observations.  相似文献   
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Microcystis aeruginosa is a well-known Cyanobacterium responsible for the formation of toxic water blooms around the world. Shallow, warm, and eutrophic reservoirs provide the most favourable conditions for M. aeruginosa development. Numerous studies have been devoted to this species, but there still is a necessity to develop additional approaches for the monitoring of cyanobacteria in reservoirs. In this study, M. aeruginosa in the water column of a hypereutrophic Siberian reservoir was investigated by fluorescence, light, and electron microscopy as well as genetic analysis using a mcyE marker. Here, we demonstrate the genetic diversity and features of the fluorescence spectra for different ecotypes of this species. We suggest that a fluorescence approach can be used to identify M. aeruginosa in a natural environment in order to increase the effectiveness of ecological monitoring and water quality evaluation.  相似文献   
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Haptoglobin (Hp) is an acute-phase protein that is produced by the liver to capture the iron that is present in the blood circulation, thus avoiding its accumulation in the blood. Moreover, Hp has been detected in a wide variety of tissues, in which it performs various functions. In addition, this protein is considered a potential biomarker in many diseases, such as cancer, including ovarian carcinoma; however, its participation in the cancerous processes has not yet been determined. The objective of this work was to demonstrate the expression of Hp and its receptor CCR2 in the ovarian cancer cells and its possible involvement in the process of cell migration through changes in the rearrangement of the actin cytoskeleton using western blot and wound-healing assays and confirming by confocal microscopy. Ovarian cancer cells express both Hp and its receptor CCR2 but only after exposure to ascitic fluid, inducing moderated cell migration. However, when the cells are exposed to exogenous Hp, the expression of CCR2 is induced together with drastic changes in the actin cytoskeleton rearrangement. At the same time, Hp induced cell migration in a much more efficient manner than did ascitic fluid. These effects were blocked when the CCR2 synthetic antagonist RS102895 was used to pretreat the cells. These results suggest that Hp-induced changes in the cell morphology, actin cytoskeleton structure, and migration ability of tumor cells, is possibly “preparing” these cells for the potential induction of the metastatic phenotype.  相似文献   
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For the identification of ecologically significant dominant groups of phytoplanktonic algae a polychromatic DCMU-induced fluorescence method is recommended. A special fluorometer equipped with a system of replaceable filters is used to differentiate three regions of the spectrum (410 ± 20, 510 ± 20 and 540 ± 10 nm) that can excite the basic light-harvesting pigments. Total and differential (for every algal taxon studied) chlorophyll a calculated from the fluorescence signals is in good agreement with biomass estimates from direct cell counts for several different trophic types of aquatic systems. This is made possible by the vizualization of the ratios of fluorescence signal values in their own coordinates: first, to decide whether it is necessary to correct linear equations in order to eliminate negative solutions; second, to determine the possibility of nulling the negative solution if a point is situated close to a side of the triangle; and third, to reduce the number of linear algebraic equations to two if the points are situated along one of the triangle sides or to one if the points are gathered at the apex. The polychromatic DCMU-induced fluorescence method can be used for monitoring natural phytoplankton populations to detect changes in their taxonomic structure.  相似文献   
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The encyrtid genus Comperiella Howard has so far not been reported in the Philippines, where there is currently an outbreak of the coconut scale insect Aspidiotus rigidus Reyne particularly in the southern parts of the island of Luzon and in some areas in Mindanao. Among Comperiella species, only C. unifasciata Ishii has been reported as a parasitoid of A. rigidus. We report not only new sightings of this parasitoid genus in the Philippines from surveys conducted in parts of the provinces of Laguna and Batangas, but also the discovery of a possibly new species that, like C. unifasciata, has been found to parasitize A. rigidus at a high rate. These findings have presented a potential of biological control against the coconut scale insect problem that has threatened the coconut industry in the country.  相似文献   
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The effect of unithiol and acetylcysteine on lipid peroxidation, thioldisulfide equilibrium, glucose-6-phosphate dehydrogenase, glutathione reductase and lactate dehydrogenase activity and on erythrocyte resistance was studied in guinea-pigs during sensitization with C. maltosa. Sensibilized animals receiving thiol antioxidants showed partial restoration of normal biochemical levels.  相似文献   
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