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991.
Adipokines have been implicated in the pathogenesis of atherosclerosis via pro-inflammatory mechanisms contributing to insulin resistance. The adipokine resistin causes endothelium dysfunction, which plays an important role in sustaining atherogenesis. This study investigated whether resistin induced expression of cell adhesion molecules and integrins in endothelial cells and THP-1 monocytes and whether such induction was attenuated by 1-20 μM caffeic acid. Resistin enhanced endothelial expression of vascular cell adhesion molecule 1 (VCAM-1), intercellular cell adhesion molecule 1 (ICAM-1), and E-selectin and monocyte expression of β1, β2, and α4 integrins. The enhancement of these proteins was diminished by caffeic acid with reduced THP-1 cell adhesion on activated endothelium. Caffeic acid at ≤20 μM demoted resistin-stimulated interleukin 8 (IL-8) production responsible for ICAM-1 and β2 integrin induction. The endothelial up-regulation of IL-8 secretion by resistin entailed toll-like receptor 4 (TLR4) activation, but caffeic acid diminished IL-8 production and TLR4 induction. Furthermore, caffeic acid encumbered resistin-activated nuclear factor κB (NF-κB) signaling. These results demonstrate that caffeic acid blocked monocyte trafficking to resistin-activated endothelium via disturbing NF-κB signaling responsive to IL-8. Therefore, caffeic acid may have therapeutic potential in preventing obesity-associated atherosclerosis.  相似文献   
992.
We examined the sorption of heavy metals and polycyclic aromatic hydrocarbons (PAHs) to surface-oxidized activated carbon (AC) and its effect on the distribution of those compounds in sediments. Created surface oxygen groups on AC enhanced the sorption of copper, which is superior in sorption competition, in the marine sediments. In case of cadmium, aqueous chemistry altered by AC addition, such as pH, has greater impact on the bioavailability according to the result of a sequential extraction combined with the pore water concentration measurements. Oxidized AC exhibited 2.3 times more adsorption of reduced bioavailable copper while 23% of bioavailable cadmium was adsorbed onto unmodified AC. No significant changes in BET surface area, pore volume, and AC/water distribution coefficient (K AC) of PAHs were observed with surface-oxidized AC. The largest difference in K AC after the oxidation was only 0.14 log unit. Consequently, freely dissolved aqueous concentrations of PAHs were reduced by more than 96% for all tested ACs in a week despite the increased Cu sorption on AC. This indicates that enhanced metal sorption by surface oxidation of AC is less significant in controlling bioavailability of PAHs in sediments than particle size or sorbent dose.  相似文献   
993.
Doubled haploid wheat lines developed from a cross between a hard white winter wheat variety of normal starch endosperm and a waxy wheat variety were used to determine the effects of allelic variation in Wx‐1, Glu‐D1, Glu‐B3, and Pinb‐D1 loci on physiochemical properties of flour, noodle dough properties, and textural quality of cooked noodles. Milling yield, damaged starch content, protein content, and SDS sedimentation volume of flour were influenced the most by allelic composition of Pinb‐D1 loci, less by Wx‐1 loci, and least by Glu‐B3. Wheat lines carrying Pinb‐D1b or Glu‐B3h alleles exhibited higher milling yield and damaged starch content of flour than those with Pinb‐D1a and Glu‐B3d alleles. Wheat lines carrying the Pinb‐D1b allele were higher in protein content and SDS sedimentation volume than those carrying Pinb‐D1a. Mixograph water absorption was largely influenced by allelic composition of Wx‐1 loci, whereas mixograph mixing time and mixing tolerance were predominantly determined by allelic composition of Glu‐D1 loci. Amylose content and pasting properties of starch were mainly determined by allelic composition of Wx‐1 loci with little influence by allelic compositions of Glu‐D1, Glu‐B3, and Pinb‐D1 loci. Allelic composition of Wx‐1 loci contributed 53.4% of the variation in optimum water absorption of noodle dough and 26.7% of the variation in thickness of the noodle dough sheet. The variation of 7.8% in optimum water absorption of noodle dough was contributed by the allelic composition of Pinb‐D1 loci. Allelic composition of Wx‐1 loci was responsible for 73.2, 74.4, and 59.6% in the variation of hardness, springiness, and cohesiveness of cooked noodles, respectively. Cohesiveness of cooked noodles was also influenced by the allelic compositions of Glu‐B3 and Pinb‐D1 loci to a smaller extent.  相似文献   
994.
Irrigation water quality influences many aspects of agroecosystems, but less is known about how complex microbial and biological communities respond to changing water quality due to causes such as reuse irrigation. The objectives of this study are to monitor and assess the environmental impacts of reclaimed wastewater irrigation on water quality and soil that might cause potential health hazards and to assess its agro-environmental effects. Two sites, which are irrigated by filtered wastewater after UV (Ultraviolet) treatment and from an agricultural reservoir that satisfied the agricultural water quality standards of Korea, were selected as treatment and control, respectively. The environmental impacts of irrigation water quality on paddy soil, microorganisms, and arthropods were investigated. Monitoring results for water, soil, health risks, and eco-environments of the reclaimed wastewater irrigation site demonstrated no adverse effects in the paddy field. This research showed that reclaimed wastewater irrigation did not present significant environmental risks for the rice paddy agroecosystem, although long-term monitoring is needed to fully characterize its effects.  相似文献   
995.
996.
Brassica rapa (chinese cabbage) is one of the main vegetable crops grown in Asian countries. Pectobacterium carotovorum subsp. carotovorum causes severe economic loss in this crop as well as in other Brassica crops through soft rot disease. Cysteine proteases like bromelain, papain or ficin show toxic effects to herbivorous insects and pathogenic bacteria. They have been known to be critical factors in plant defence mechanisms. The current study investigated the effect of bromelain gene (BL1) of pineapple (Ananas comosus L. Merrill) on enhancing resistance to soft rot in transgenic Brassica rapa ‘Seoulbaechu’. Three homozygous T2 lines were inoculated with Pectobacterium carotovorum subsp. carotovorum and BL8-2 line showed the lowest rate of infected leaves (RIL) in both wound inoculation and non-wound inoculation, when the non-infected line showed 100 % RIL in both cases. The highest expression of BL1 gene was also observed in BL8-2 homozygous line. Thus, the over-expressed BL1 gene conferred enhanced resistance to soft rot in Brassica rapa.  相似文献   
997.
Polyurethanes are polymers with urethane linkages in their backbone. It is prepared by polyaddition polymerization between isocyanates and polyols, which produce different chemical, physical, and mechanical properties depending on their types and characteristics. Previous reports of polyurethane foams prepared by using PEG polyol indicated prominent features in the elasticity and recovery of the foams. However, it is necessary to improve the mechanical strength of these materials. In this study, polyurethane foams were prepared using a PLA/PEG polyol mixture and 1,6-hexamethylene diisocyanate. PLA polyol was synthesized by the direct condensation polymerization of lactic acid. The polyurethane foams were characterized using FE-SEM analysis, FT-IR spectroscopy, water absorbency measurement, and mechanical property measurement. In FE-SEM analysis, it was shown that the PLA content of polyol mixture significantly affected the porous structure. FT-IR spectra confirmed that urethane linkages formed between the PLA/PEG polyols and the isocyanates. The water absorbency decreased due to the hydrophobicity of PLA. With respect to the mechanical properties, the breaking stress and the Young’s modulus increased with increasing PLA content. When the PLA content of polyols was 60 and 70 percent, the breaking strain was significantly higher than those of other polyurethane foams.  相似文献   
998.
In this study, waste lignocellulosic sawdust was converted to carboxymethylcellulose (CMC) by the combination process of an inorganic base (NaOH) and a weak acid (monochloroacetic acid, MCA). Optimum conditions for the pretreatment were studied on the basis of lignin and hemicellulose removal. NaOH and MCA concentration, reaction time, and operating temperature were the parameters studied to acquire the optimized conditions for the production of CMC. Degree of substitution (DS) and solubility were greatly influenced by the changes in the experimental conditions. DS increased on increasing the concentration of NaOH and MCA but the effect was more profound during the NaOH loading. A maximum DS of 0.5 was obtained on the treatment with 20 % NaOH and 20 % MCA concentration at 50 °C, 150 rpm for 4 h. 1.28 g CMC/g cellulose was obtained at the optimized set of conditions. Structural information of cellulose and CMC was obtained using IR spectroscopy and the surface morphology was studied using field emission scanning electron microscopy (FESEM). Carboxymethylcellulose showed lower crystallinity than the native cellulose extracted from sawdust which was studied using X-ray diffraction.  相似文献   
999.
This study developed a system that automatically created individually customized patterns by combining the two methods of “automatic drafting by pattern formulae” and “grading”. The system reads four kinds of information: body measurements; basic size pattern; grading values of the pattern’s points; and an alteration rule. Using the files, the system automatically generated a grading pattern first, and then modified it according to the alteration rule to make individually customized patterns. The clothing produced from the customized pattern fit the subject better than the clothing produced from the grading method.  相似文献   
1000.
Global warming is increasing the variability of climate change and intensifying hydrologic cycle components including precipitation, infiltration, evapotranspiration, and runoff. These changes increase the chance of more severe and frequent natural conditions, and limit ecosystem function and human activities. Adaptation to climate change requires assessment of the potential disaster risk. The objectives of this study were to estimate the flood risk index (FRI) considering regional flood characteristics at the national level and to prioritize the factors affecting flood risk through principal component analysis. FRI was estimated based on the Delphi survey results from 50 water resources experts in South Korea. The potential risk analysis was conducted for 229 local governments in South Korea. The results showed that natural and social factors were more influential flood risk factors to South Korea than administrative and economic and facility factors. Specifically, natural, social, administrative and economic, and facility factors were, respectively, highest at Jindo-Gun in Jennam-Do, Gumi-Si in Kyongsanbuk-Do, Dong-Gu in Incheon-Si, and Suwon-Si, Kyonggi-Do. Overall, the highest FRI is shown in Anyang-Si, Kyongggi-Do. The spatial distribution of the FRI was high in the southeastern coastal region and basins of the two biggest rivers in South Korea, and normalized flood frequency followed spatial patterns similar to FRIs. This study provided information on the relative flood risk index among administrative units for investment prioritization in flood risk management. In this regard, the suggested FRI is expected to significantly contribute to methodical and economic improvements in budget allocations for flood risk management.  相似文献   
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