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Mellish MA Adreani CM 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(2):180-182
A 5-year-old, Quarter horse mare was treated for severe cellulitis secondary to a gunshot wound near the right humerus. The bullet was not retrieved due to the risk of damaging the radial nerve or elbow joint. Despite the presence of the bullet, the mare resumed athletic soundness once the infection had resolved. 相似文献
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Isabel Blanco Ana Canals Gary Evans Martha A. Mellencamp Carmen Cia Nader Deeb Lizhen Wang Lucina Galina-Pantoja 《Canadian journal of veterinary research》2008,72(3):228-235
In animal breeding programs, deoxyribonucleic acid (DNA) markers can be used to identify sires that are less susceptible to disease. These DNA markers are typically discovered in populations that display differences in susceptibility. To find those differences, it was hypothesized that sires influence their offspring responses to infection with H. parasuis. To identify differences in susceptibility, colostrum-deprived pigs derived from 6 sires were inoculated with a virulent strain of H. parasuis serovar 5. Pigs were infected at 21-d of age and euthanized 1, 2, or 3 days post-infection. Rectal temperatures, bacterial detection, clinical signs, and lesions were measured by comparing disease susceptibility in the offspring from each sire. The effect of the sire on the severity of disease in the offspring was statistically analyzed using to a 2-way ANOVA with sire and test day as fixed effects. Significant differences among sires were found for lesions, rectal temperatures from days 0-1 and 0-2 (P < 0.05) and marginal effects for clinical signs (P = 0.08). On average, the offspring of sire H94 was the most susceptible to challenge. Responses to infection were categorized to determine the clinical responses and analyzed by Chi square. Overall, 10% of all pigs infected were fully resistant to H. parasuis infection. Boar H94 didn't produce any fully resistant offspring. Differences in susceptibility to H. parasuis were observed, and the results support the hypothesis that sires influence their offspring's response to infection. Tissues from this population could be used to identify DNA markers for genetic selection of sires that produce offspring more resistant to H. parasuis infection. 相似文献
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Kenneth S. Evans Martha Mamo Ana Wingeyer Walter H. Schacht Kent M. Eskridge Jeff Bradshaw Daniel Ginting 《Strength and Conditioning Journal》2019,72(4):667-677
Soil fauna play critical roles in various ecosystem functions and services, but empirical data measuring their impact on dung pat decomposition and subsequent nutrient cycling into rangeland soils are limited. The objective of this study was to quantify the effect of soil fauna, using dung beetle as an indicator, on dung decomposition and subsequent translocation of dung nutrients into grassland soil over time. A field experiment was conducted early in the summer season and late in the summer season of 2014 and 2015. In each season, dung beetle abundance, changes in dung properties, and subsequent translocation of dung nutrients into soils were evaluated at 1, 3, 7, 14, 28, and 56 d after placement (DAPs) of exposed dung and nonexposed dung to beetles. Analysis of no-dung control soil was included for comparison. Dung beetles contributed 7% and 4% in the losses of dung moisture and dry matter (DM), respectively; however, dung beetles had no effect on dung pat nutrients. Losses of dung nutrients—42% of water-extractable organic carbon, 46% of water-extractable phosphorus, and 65% of NH4—occurred during the first 14 DAPs. Dung beetles increased soil nutrients in the top 10-cm depth beneath the dung. No effect of beetles was observed in deeper (> 10-cm) soil depth or in soil 30 cm away from the dung. This study concluded that soil fauna, such as dung beetles, accelerated dung moisture and DM losses and subsequent nutrient increase into the top 10 cm of soil. 相似文献
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Development of a Model to Simulate Nitrogen Dynamics in an Integrated Shrimp–Macroalgae Culture System with Zero Water Exchange 下载免费PDF全文
Adolfo Sánchez‐Romero Anselmo Miranda‐Baeza Martha Elisa Rivas‐Vega José Antonio López‐Elías Luis Rafael Martínez‐Córdova Armando Tejeda‐Mansir 《Journal of the World Aquaculture Society》2016,47(1):129-138
The effluents of traditional shrimp monoculture cause pollution and promote eutrophication and hypernutrification of the receiving coastal ecosystems. Integrated aquaculture and a recirculating aquaculture system (RAS) have been proposed as an alternative to address these problems. In this study, we developed a dynamic model to simulate the concentration of total ammonia nitrogen (TAN), nitrite, and nitrate in an integrated culture of whiteleg shrimp, Litopenaeus vannamei, and seaweed, Gracilaria vermiculophylla, in a recirculating and zero water exchange system, and the effect of nitrifying and heterotrophic bacteria was also included. The experiments demonstrated that a dynamic model can explain the concentrations of dissolved inorganic nitrogen and variations in these concentrations over time in the integrated culture. The results also suggest that nitrifying and heterotrophic bacteria play an important role in the transformation of dissolved nitrogenous compounds; therefore, these bacteria should be considered within the dynamics of nitrogen in integrated systems with low water exchange. 相似文献
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Hoskins RA Carlson JW Kennedy C Acevedo D Evans-Holm M Frise E Wan KH Park S Mendez-Lago M Rossi F Villasante A Dimitri P Karpen GH Celniker SE 《Science (New York, N.Y.)》2007,316(5831):1625-1628
Genome sequences for most metazoans and plants are incomplete because of the presence of repeated DNA in the heterochromatin. The heterochromatic regions of Drosophila melanogaster contain 20 million bases (Mb) of sequence amenable to mapping, sequence assembly, and finishing. We describe the generation of 15 Mb of finished or improved heterochromatic sequence with the use of available clone resources and assembly methods. We also constructed a bacterial artificial chromosome-based physical map that spans 13 Mb of the pericentromeric heterochromatin and a cytogenetic map that positions 11 Mb in specific chromosomal locations. We have approached a complete assembly and mapping of the nonsatellite component of Drosophila heterochromatin. The strategy we describe is also applicable to generating substantially more information about heterochromatin in other species, including humans. 相似文献
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Martha Regina Lucizano Garcia 《Archives of Agronomy and Soil Science》2013,59(5):511-525
The effects of agricultural–pastoral and tillage practices on soil microbial populations and activities have not been systematically investigated. The effect of no-tillage (NT), no-tillage agricultural–pastoral integrated systems (NT-I) and conventional tillage (CT) at soil depths of 0–10, 10–20 and 20–30 cm on the microbial populations (bacteria and fungi), biomass-C, potential nitrification, urease and protease activities, total organic matter and total N contents were investigated. The crops used were soybean (in NT, NT-I and CT systems), corn (in NT and NT-I systems) and Tanner grass (Brachiaria sp.) (in NT-I system); a forest system was used as a control. Urease and protease activities, biomass-C and the content of organic matter and total N were higher (p < 0.05) in the forest soil than the other soils. Potential nitrification was significantly higher in the NT-I system in comparison with the other systems. Bacteria numbers were similar in all systems. Fungi counts were similar in the CT and forest, but both were higher than in NT. All of these variables were dependent on the organic matter content and decreased (p < 0.05) from the upper soil layer to the deeper soil layers. These results indicate that the no-tillage agricultural–pasture-integrated systems may be useful for soil conservation. 相似文献
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