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101.
Ecological associations are the inter-relationship between the species and their environment. Oceanographic processes like upwelling events and formation of eddies, rings, and fronts have been monitored using National Oceanic and Atmospheric Administration Advanced Very High Resolution (NOAA AVHRR) and Indian Remote Sensing Satellite-P4-Ocean Colour Monitor (IRS-OCM) data. Sea Surface Temperature (SST) and chlorophyll concentration (CC) images were derived from AVHRR and OCM, respectively. Upwelling event was monitored using AVHRR-SST by detecting the differences in surface water temperature. The formation of eddies, rings, cyclonic eddies, and anti-cyclonic eddies and their biological responses were studied using CC. Eddies and rings were found with high phytoplankton production in the form of bloom, which provide grazing ground for fishes. The anti-cyclonic eddies were found with very low CC, indicating the biological deserts in the ocean. The impacts of these processes on fish catch were studied using fishing operations data procured from Fishery Survey of India. In this paper, the occurrence of different oceanographic processes, their persistence, and relevance with catch statistics of fishery resources in the study area are discussed. The study explains the potentials of satellite remote sensing to establish the habitat linkage between oceanographic processes and fishery resources. Guest editor: V. D. Valavanis Essential Fish Habitat Mapping in the Mediterranean  相似文献   
102.
Bioconversion of wheat straw using Phanerochaete chrysosporium was carried out in a 200l staged vertical reactor. The bioconversion process was characterized by measuring the percentage degradation of lignin and cellulose, and increment in crude protein content. The effect of airflow rate, inoculum amount and wheat straw loading on bioconversion was investigated using a statistical experimental design. An analysis of variance was performed to determine response surfaces. The quality of bioconversion indicated by an optimization index called the desirability coefficient had the highest value of 0.75 for the fifth day of cultivation. This corresponded to an operating condition of 1.5kg wheat straw per stage using an inoculum amount of 0.38g (100g dry wheat straw)(-1) and an airflow rate of 15lmin(-1). The lignin and cellulose degradation achieved at this operating condition was 27% and 29%, respectively. A ratio of 3 for the weight of wheat straw to inoculum amount gave the highest crude protein of 5.9% on dry weight basis. Among the variables investigated, the airflow rate exhibited a significant effect on the quality of bioconversion. Our results indicate that the quality of bioconversion may be controlled by implementing a predetermined airflow rate schedule.  相似文献   
103.
We present here the results of protein extraction from different ocular regions using different detergents. Extraction strategies used to determine optimal protein extraction included: pressure cycling and aqueous-organic phase extraction in combination with electrophoretic fractionation for anterior, posterior, and peripapillary sclera. Detergent extraction of proteins from freshly enucleated porcine eyes (n = 8) showed significant differences for different eye regions. Protein yield ranged from 2.3 to 50.7 mug protein/mg for different ocular tissues, with the lens yielding the most protein. ASB-14 and Triton X-100 provided the best protein yields (n = 10) for anterior and posterior sclera. The spectrophotometric measurements for ASB-14 were not consistent with SDS-PAGE densitometry. A combination of 0.5% Triton X-100, 0.5% Tween-20, and 0.1% Genapol C-100 was found optimal for extraction from sclera. Proteins from different regions of the eye are best extracted with different detergents. The pressure cycling technology provided superior extraction compared to the other methods. Additional aqueous-organic phase partitioning enables superior fractionation when compared to SDS-PAGE alone. Organic phase fractionation is compatible with MS and allowed identification of 34, 71, and 77 proteins respectively from anterior, posterior, and peripapillary sclera. The extraction strategy may affect the final outcome in protein profiling by MS or by other methods.  相似文献   
104.
105.
Vegetation growth models are used with remotely sensed and meteorological data to monitor terrestrial carbon dynamics at a range of spatial and temporal scales. Many of these models are based on a light-use efficiency equation and two-component model of whole-plant growth and maintenance respiration that have been parameterized for distinct vegetation types and biomes. This study was designed to assess the robustness of these parameters for predicting interannual plant growth and carbon exchange, and more specifically to address inconsistencies that may arise during forest disturbances and the loss of canopy foliage. A model based on the MODIS MOD17 algorithm was parameterized for a mature upland hardwood forest by inverting CO2 flux tower observations during years when the canopy was not disturbed. This model was used to make predictions during a year when the canopy was 37% defoliated by forest tent caterpillars. Predictions improved after algorithms were modified to scale for the effects of diffuse radiation and loss of leaf area. Photosynthesis and respiration model parameters were found to be robust at daily and annual time scales regardless of canopy disturbance, and differences between modeled net ecosystem production and tower net ecosystem exchange were only approximately 2 g C m−2 d−1 and less than 23 g C m−2 y−1. Canopy disturbance events such as insect defoliations are common in temperate forests of North America, and failure to account for cyclical outbreaks of forest tent caterpillars in this stand could add an uncertainty of approximately 4–13% in long-term predictions of carbon sequestration.  相似文献   
106.
In this study, Lactobacillus bulgaricus NCDC (09) and Lactobacillus fermentum TDS030603 (LBF) were evaluated for their ACE-inhibitory activity and peptides production under optimized conditions from fermented camel milk (Camelus dromedarius). Lactic cultures were evaluated for their pepX activity, proteolytic activity and ACE-inhibitory activity. 09 culture exhibited higher PepX and ACE-inhibitory activity than LBF. 2% rate of inoculation and 12 h of incubation were optimized on the basis of pepX and proteolytic activity. Purified peptides from fermented camel milk were characterized by amino acids profiling through the search in BlastP, Protein information resource (PIR) databases. ACE-inhibitory activity of different peptides from fermented camel milk were also confirmed by the database of antihypertensive peptides (AHTPDB). Fermented camel milk produced by Lactobacillus cultures could be a novel source of ACE-inhibitory peptides.  相似文献   
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108.
In the sporadic permafrost zone of northwestern Canada, boreal forest carbon dioxide (CO2) fluxes will be altered directly by climate change through changing meteorological forcing and indirectly through changes in landscape functioning associated with thaw‐induced collapse‐scar bog (‘wetland’) expansion. However, their combined effect on landscape‐scale net ecosystem CO2 exchange (NEELAND), resulting from changing gross primary productivity (GPP) and ecosystem respiration (ER), remains unknown. Here, we quantify indirect land cover change impacts on NEELAND and direct climate change impacts on modeled temperature‐ and light‐limited NEELAND of a boreal forest–wetland landscape. Using nested eddy covariance flux towers, we find both GPP and ER to be larger at the landscape compared to the wetland level. However, annual NEELAND (?20 g C m?2) and wetland NEE (?24 g C m?2) were similar, suggesting negligible wetland expansion effects on NEELAND. In contrast, we find non‐negligible direct climate change impacts when modeling NEELAND using projected air temperature and incoming shortwave radiation. At the end of the 21st century, modeled GPP mainly increases in spring and fall due to reduced temperature limitation, but becomes more frequently light‐limited in fall. In a warmer climate, ER increases year‐round in the absence of moisture stress resulting in net CO2 uptake increases in the shoulder seasons and decreases during the summer. Annually, landscape net CO2 uptake is projected to decline by 25 ± 14 g C m?2 for a moderate and 103 ± 38 g C m?2 for a high warming scenario, potentially reversing recently observed positive net CO2 uptake trends across the boreal biome. Thus, even without moisture stress, net CO2 uptake of boreal forest–wetland landscapes may decline, and ultimately, these landscapes may turn into net CO2 sources under continued anthropogenic CO2 emissions. We conclude that NEELAND changes are more likely to be driven by direct climate change rather than by indirect land cover change impacts.  相似文献   
109.
MicroRNAs (miRNAs) are generated by endonuclease activity of Dicer, which also helps in loading of miRNAs to their target sequences. SH-SY5Y, a human neuroblastoma and a cellular model of neurodevelopment, consistently expresses genes related to neurodegenerative disorders at different biological levels (DNA, RNA, and proteins). Using SH-SY5Y cells, we have studied the role of Dicer and miRNAs in neuronal differentiation and explored involvement of P53, a master regulator of gene expression in differentiation-induced induction of miRNAs. Knocking down Dicer gene induced senescence in differentiating SH-SY5Y cells, which indicate the essential role of Dicer in brain development. Differentiation of SH-SY5Y cells by retinoic acid (RA) or RA + brain-derived neurotrophic factor (BDNF) induced dramatic changes in global miRNA expression. Fully differentiated SH-SY5Y cells (5-day RA followed by 3-day BDNF) significantly (p < 0.05 and atleast >3-fold change) upregulated and downregulated the expression of 77 and 17 miRNAs, respectively. Maximum increase was observed in the expression of miR-193-5p, miR-199a-5p, miR-192, miR-145, miR-28-5p, miR-29b, and miR-222 after RA exposure and miR-193-5p, miR-146a, miR-21, miR-199a-5p, miR-153, miR-29b, and miR-222 after RA + BDNF exposure in SH-SY5Y cells. Exploring the role of P53 in differentiating SH-SY5Y cells, we have observed that induction of miR-222, miR-192, and miR-145 is P53 dependent and expression of miR-193a-5p, miR-199a-5p, miR-146a, miR-21, miR-153, and miR-29b is P53 independent. In conclusion, decreased Dicer level enforces differentiating cells to senescence, and differentiating SH-SY5Y cells needs increased expression of P53 to cope up with changes in protein levels of mature neurons.  相似文献   
110.
The purpose of this study was to evaluate the effect of formulation components on the in vitro skin permeation of microemulsion drug delivery system containing fluconazole (FLZ). Lauryl alcohol (LA) was screened as the oil phase of microemulsions. The pseudo-ternary phase diagrams for microemulsion regions were constructed using LA as the oil, Labrasol (Lab) as the surfactant and ethanol (EtOH) as the cosurfactant. The formulation which showed a highest permeation rate of 47.15 ± 1.12 μg cm−2 h−1 and appropriate physicochemical properties was optimized as containing 2% FLZ, 10% LA, 20% Lab/EtOH (1:1), and 68% double-distilled water (w/w). The efficiency of microemulsion formulation in the topical delivery of FLZ was dependent upon the contents of water and LA as well as Lab/EtOH mixing ratio. It was concluded that the percutaneous absorption of FLZ from microemulsions was enhanced with increasing the LA and water contents, and with decreasing the Lab/EtOH ratio in the formulation. Candida albicans was used as a model fungus to evaluate the antifungal activity of the best formula achieved, which showed the widest zone of inhibition as compared to FLZ reference. The studied microemulsion formulation showed a good stability for a period of 3 months. These results indicate that the studied microemulsion formulation might be a promising vehicle for topical delivery of FLZ.  相似文献   
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