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941.
The importance of the linkage between nutrition and health is a hot issue. Like other food-related sectors, the meat industry is undergoing foremost transformations, driven among other things by changes in consumer requirements. The present study was designed to evaluate the lipid stability and antioxidative potential of leg and breast microsomal fraction of broiler meat fed on ALA and ATA. For the first 3 weeks of growth, broilers were fed on feed supplemented with ATA (200 mg/kg of feed) and during the last 3 weeks broilers were fed on feed supplemented with ALA (25, 75, 150 mg/kg of feed) and a constant level of ATA (200 mg/kg of feed). The body weight of the carcass was measured after every week of growth until 6 weeks. Positive correlation between the antioxidant activity and the TPC was observed. Higher values of TBARS were detected in leg muscles than in breast muscles. HPLC data revealed ALA and ATA contents were higher in T(4) (leg, 5.55 ± 0.19 and 3.87 ± 0.15 μg/mg of protein; breast, 5.63 ± 0.20 and 2.03 ± 0.10 μg/mg of protein, respectively) and lowest in T(5) (ALA, leg, 1.40 ± 0.06 μg/mg of protein; breast, 1.54 ± 0.05 μg/mg of protein; ATA, leg, 1.25 ± 0.06 μg/mg of protein; breast, 0.63 ± 0.008 μg/mg of protein), in which the only oxidized oil was used. Oxidized oil in feed reduced weight gain and increased TBARS, whereas TPC, DPPH, ALA, and ATA values decreased in both leg and breast meat.  相似文献   
942.
The streptomycetes in the horizons of two pine forest soils were enumerated and isolated using neutral and acidified media. The pH requirements of all species isolated were tested in culture and two distinct groups, neutrophiles and acidophiles, were recognized. Growth of representative species at different pH in liquid medium and sterile soil was studied and found to be similar. The significance of the existence of both acidophilic and neutrophilic species in acid soils was discussed. It was suggested that acidophilic actinomycetes may be more widespread and important in soil than has been thought previously.  相似文献   
943.
We previously developed a new simple technique of methylene blue (MB) staining for the discrimination of aluminum (Al)-tolerant protoplasts from 4 plant species (rice, oats, maize and pea). The objectives of the present study were to confirm the applicability of this technique to a wider range of plant species, cultivars and lines, and to identify a common strategy for the early stage of Al tolerance. A total of 10 plant species, two Brachiaria spp., two Oryza spp., buckwheat, maize, pea, triticale, wheat and barley, corresponding to 18 different plant samples (species, cultivars, and lines), were used. Al tolerance (relative net root elongation of the longest root), which was screened at 20 μM AICI3 in 0.2 mM CaCl2 (pH 4.9) for 24 h, ranged widely from 10 to 88. Among cultivars and lines within the same species, Al accumulation in the root tip portion was higher in Al-sensitive plants, corresponding to more severe permeabilization of the plasma membranes (PM). Protoplasts isolated mainly from the epidermis, and outer and central parts of the cortex were stained to different degrees by MB, and the blue color was observed both on the surface and inside the protoplasts. Color pictures obtained after staining for 3 min with 0.1% MB were analyzed by Image Hyper II. The ratio of the heavily stained area at threshold 95 to the entire area stained with MB at threshold 125 was defined as MB stainability. MB stainability was negatively correlated with Al tolerance ( y = 48.6e−0.02 x , R 2= 0.676**) suggesting the common importance of permeation characteristics of PM, in addition to PM negativity for Al tolerance in a wide range of plant species, cultivars and lines. Analysis of the PM lipid composition was proposed as an important topic for future studies on the negativity and permeation of PM.  相似文献   
944.
Biological, chemical and bio‐chemical strategies have been tested in the past for reclamation of saline‐sodic and sodic soils. The efficiency of two crop rotations (rice‐wheat and Sesbania‐wheat) alone or in combination with either gypsum (CaSO4.2H2O) or sulfuric acid (H2SO4) was tested for ionic displacement from four saline‐sodic soils. Pure gypsum was applied at 50 per cent of soil gypsum requirement at the time of planting rice and Sesbania, whereas 95 per cent pure sulfuric acid was added at 50 per cent soil gypsum requirement as one‐third applications by mixing with the first three irrigations. The rice crop biomass decreased at a soil saturation extract electrical conductivity (ECe) of 8 dS m−1, whereas wheat and Sesbania were influenced at a sodium adsorption ratio (SAR) of ≥40. Gypsum treatment helped the crops flourish well at these ECe and SAR levels. The infiltrated volume of water dropped with decrease in ECe : SAR ratio of soils and increase in crop biomass production. Crops rotation treatments alone helped leach sodium (Na+) and other ions successfully at SAR ≤ 21 but were less effective at SAR ≥ 40 at which point plants growth was also curtailed. Gypsum and H2SO4 treatments significantly aided leaching of Na+ and other ions with water at SAR ≥ 40 under both the crop rotations. Hence, crops effectively reclaimed soil at low sodicity level, whereas at high SAR, chemical amendments are obligatory in order to reclaim soils. This study also suggests that the required dose of H2SO4 should be applied with pre‐planting irrigation for better yield of the first crop. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
945.
Maize ( Zea mays L.) plants were grown in the field and labelled with 14CO2 at four leaf positions from silking up to maturity. The ear leaf was the most important source of labelled photosynthates to the ear, followed by the first leaf blade above and below the ear. The movement of labelled assimilates from the second leaf blade below the ear was predominantly downwards. The ear became an important sink soon after silking and continued in importance till harvest.
Initially assimilates were partitioned within the ear as husk < cob < grains but at harvest as grains < cob < husk. There was considerable remobilization of assimilates from the husk and stem. Removal of leaves drastically altered the pattern of distribution of labelled photosynthates and the direction of movement was determined by the position of the source leaf blade and the defoliation treatment. Darkening the leaf blades did not much alter the translocation of the labelled photosynthate and increased slightly its proportion to the grains. The removal of the ear severely altered the pattern of distribution of 14C, which was mostly deposited in the stem.  相似文献   
946.
947.
Male and female rats injected with 14C-photoheptachlor (0.93 mg/kg, ip) voided 66.3 and 28.1% of the radioactivity, respectively, in 4 weeks. Fecal route of elimination was more important than the urinary in both sexes. Tissue distribution of the residues at the end of the 4-week period showed higher levels in females than in males and the main storage site was the adipose tissue. Eleven metabolites of photoheptachlor from feces and nine from the urine of treated rats were isolated, purified, and chromatographically characterized.  相似文献   
948.
949.
This paper identifies the economic and physical benefits attributable to precision land leveling. While the work is specific to Pakistan the implications are relevant for other arid areas of the world where irrigation is practiced.Two sets of fields were selected, one set that had been precision leveled and another set that had been leveled using traditional techniques. These fields were resurveyed and then the farmers were interviewed every month during the winter crop season. Cutting samples were taken on all the fields during harvest. The average yield of the precision leveled fields was 2274.7 kg/ha and the yield for traditional leveled was 1681.1 kg/ha. This difference is significant at the 0.001 level. In addition the mean time to irrigate a hectare field was 2.79 h for precision leveled and 5.24 h for traditional leveled. Again this is significantly different at the 0.001 level. The change yield attributable solely to precision land leveling was calculated by regression analysis at 246.1 kg/ha per 3 cm change in max—min range. The remaining difference in yields was attributable to increased use of nitrogen and phosphorus fertilizers on the precision leveled fields over the traditional leveled fields.The economic analysis of precision and leveling, assuming a life of 10 years, is positive but not above the two or three to one return that is usually required to persuade subsistent farmers to invest in a new technology. However, the precision land leveling acts as a catalyst and increases the efficiency of the other associated inputs and hence is a more valuable investment than is indicated by simple economic analysis.  相似文献   
950.
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