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Mary Jo Burkhard Dennis J. Meyer Rod A. Rosychuk Shawn P. O'Neil Patricia C. Schultheiss 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1995,9(5):357-360
A monoclonal gammopathy composed of immunoglobulin G, with concurrent light-chain proteinuria and generalized lymph node plasmacytosis, was associated with chronic pyoderma in a dog. A uniform population of plasma cells was observed cytologically and histologically in multiple lymph node specimens. A diagnosis of monoclonal gammopathy of unknown significance was eventually made by exclusion of other known causes of monoclonal gammopathy, resolution after antibiotic therapy, and no evidence of lymphoproliferative disease after 11 months of follow-up and subsequent necropsy. This report expands the diagnostic considerations for monoclonal gammopathies in the dog. 相似文献
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Change of shear resistance and compressibility of Ap-horizon material from loess-derived Parabraunerde Standardized artificial bodies prepared from soil material of a loessderived parabraunerde-Ap-horizon were tested with respect to their shear resistance and compressibility. The noncalcareous material was enriched with lime (2 stepts), soil humidity changed (3 steps) and the normal pressure increased (4 steps). Liming generally caused an increased initial shear resistance and led to a lowering of compressibility. The effect of lime is interpreted as an result of flocculation of the clay particles at the points of contact between silt grains in the soil matrix. The problems of transferring those results to the field are discussed. 相似文献
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A greater focus on manure nutrient disposition from concentrated animal-feeding operations has developed from environmentalists, concerned citizens, and regulatory agencies. The establishment and enforcement of manure nutrient regulations will alter the future of livestock production. Proposed legislation and strategies may provide a false sense of security regarding environmental preservation or restoration and may impose monitoring and record keeping on the livestock operators. Existing regulations and proposed regulations and strategies are presented. Implications of legislation and proposed strategies, policies, and regulations are discussed. Livestock operations will need to comply with regulations to remain in business and to minimize environmental liability. 相似文献
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Waterlogging of field-grown plants can occur either when the surface of slowly permeable soils is inundated or when the water-table rises so that part or all of the root zone is saturated. The effects of short-term waterlogging on field crop growth and yield have not been well quantified. To study these effects, a sloping, repacked slab of soil underlain by an impermeable membrane was constructed. The sloping plot (45 m long × 6 m wide × 0.6 m deep) was flooded by introducing water through a drainage network and gravel bed so that a gradient of water-table depth ranging from 0.1 m above to 0.66 m below the soil surface was obtained. Cotton (Gossypium hirsutum cv. Deltapine 61) was grown in the facility and the responses of plants to two periods of flooding were monitored. Soil matric potential and oxygen partial pressure data indicated that plants were subjected to a continuum of conditions ranging from complete inundation to no water-table within the root zone.The first flooding event began 82 days after sowing just prior to the main flowering period. Plants with more than 55% of their root system below the water table showed decreased leaf growth about 3–4 days after the flooding started with visible wilt symptoms and decreased leaf water potential observed on days 7 and 8 of flooding. In the second flooding event (131 days after sowing), plants showed no signs of waterlogging stress apart from reduced leaf growth despite 16 days of flooding. Plant growth response was probably more the result of reduced nutrient status (mostly nitrate) rather than a water deficit stress effect with some plant acclimatization between the first and second flooding event. Seed cotton yield data indicated that the observed stress during the first flooding event may have promoted reproductive growth in plants where the short-term water-table was greater than 0.2 m below the soil surface. 相似文献
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The effectiveness of windbreaks in windspeed reduction is often evaluated without regard to the objects to be protected. In fact, many objects may have different sensitivities to wind and often require different degrees of wind protection. Since commonly used indexes do not consider the sensitivity to wind, a concept of specific protection efficiency is developed. A critical windspeed is used to represent the sensitivity of each object. Windspeeds greater than this value are considered damaging. A dimensionless protection index is defined to evaluate windbreak efficiency. The maximum index value is 1 for the highest protection, and the index is negative when sheltered windspeed is greater than the critical windspeed. This index can be compared, summed, and averaged across different windbreaks, objects, and leeward locations. A sample of critical windspeed values was compiled from the literature. The index was evaluated using actual wind data measured under both sheltered and open conditions. The results indicated that the index can be used for evaluating windbreak effectiveness in terms of objects protected under various conditions. This model could be used as a tool for windbreak-related research and policy making. 相似文献
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Summary Oven dried basswood was vacuum impregnated with methyl methacrylate monomer containing various amounts of free radical catalyst and trifunctional crosslinking agent. The wood-monomer composite was polymerized at 60°C in an air oven and the rate of heat generated was followed by means of a thermocouple placed in the center of the sample.Increasing the concentration of Vazo free radical catalyst in the basswood-MMA impregnated samples reduces the time to the exothermic peak and increases the exothermic peak temperature. High Vazo concentrations also decraase the percentage conversion of monomer to polymer.Trimethyl propane trimethacrylate (TMPTMA) crosslinker reduces the time to the exothermic peak and dramatically increases the exothermic peak temperature. The use of a crosslinker rapidly increases the initial viscosity of the system, and therefore, the autoacceleration of the polymerization is more pronounced.Our thanks are due to DuPont Company and Sartomer Resins for supplying the monomers and catalysts. Research funds were provided by Organized Research Budget of the College of Forestry. 相似文献
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