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991.
Luis G. Arroyo Federica ter Woort John D. Baird Laetitia Tatiersky Josepha DeLay Tony van Dreumel 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(9):853-858
This report describes 5 cases of fatal Lawsonia intracellularis-associated ulcerative and necro-hemorrhagic enteritis in weanling Thoroughbred and Standardbred foals. The lesions are similar to those of the L. intracellularis-associated ulcerative and necro-hemorrhagic enteritis syndrome in pigs. Two foals had concurrent severe typhlo-colitis as a result of a large burden of encysted cyathostomes. The clinical, diagnostic, and therapeutic challenges, and the potential complications encountered during the management of such cases are discussed. 相似文献
992.
Emmanouil Roditakis Christina Skarmoutsou Marianna Staurakaki María del Rosario Martínez‐Aguirre Lidia García‐Vidal Pablo Bielza Khalid Haddi Carmelo Rapisarda Jean‐Luc Rison Andrea Bassi Luis A Teixeira 《Pest management science》2013,69(2):217-227
BACKGROUND: Tuta absoluta(Meyrick) is one of the most serious pests of tomato recently introduced in the Mediterranean region. A novel bioassay method designed for the accurate determination of insecticide toxicity on T. absoluta (IRAC method No. 022) was validated by three different laboratories [Greece (NAGREF), Italy (UC) and Spain (UPCT)] on European populations. RESULTS: The insecticides indoxacarb and chlorantraniliprole were used as reference products. The IRAC leaf dip method is easy to perform, producing repeatable, homogeneous responses. LC50 values for indoxacarb ranged between 1.8 and 17.9 mg L?1 (NAGREF), 0.93 and 10.8 mg L?1 (UC) and 0.20 and 0.70 mg L?1 (UPCT), resulting in a tenfold, 12‐fold and fourfold difference between the least and most susceptible populations at each laboratory respectively. For chlorantraniliprole, LC50 values ranged between 0.10 and 0.56 mg L?1 (NAGREF), 0.23 and 1.34 mg L?1 (UC) and 0.04 and 0.24 mg L?1 (UPCT), resulting in a sixfold difference in all three cases. Overall, UPCT reported lower mean LC50 to indoxacarb, while UC reported higher LC50 to chlorantraniliprole. CONCLUSIONS: The new bioassay is reliable, providing a useful tool in the design of IRM strategies. Within each country/lab, the variability observed in the results for both indoxacarb and chlorantraniliprole can be attributed to natural variation. Future research is necessary to determine the extent to which it is possible to compare results among laboratories. Copyright © 2012 Society of Chemical Industry 相似文献
993.
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995.
Abad-García B Berrueta LA Garmón-Lobato S Urkaregi A Gallo B Vicente F 《Journal of agricultural and food chemistry》2012,60(14):3635-3644
The data set composed by phenolic compound profiles of 83 Citrus juices (determined by HPLC-DAD-MS/MS) was evaluated by chemometrics to differentiate them according to Citrus species (sweet orange, tangerine, lemon, and grapefruit). Cluster analysis (CA) and principal component analysis (PCA) showed natural sample grouping among Citrus species and even the Citrus subclass. Most of the information contained in the full data set can be captured if only 15 phenolic compounds (concentration ≥10 mg/L), which can be quantified with fast and accurate methods in real samples, are introduced in the models; a good classification which allows the confirmation of the authenticity of juices is achieved by linear discriminant analysis. Using this reduced data set, fast and routine methods have been developed for predicting the percentage of grapefruit in adulterated sweet orange juices using principal component regression (PCR) and partial least-squares regression (PLS). The PLS model has provided suitable estimation errors. 相似文献
996.
Leandro Sousa-Souto Danielle Caroline de Jesus Santos Bianca Giuliano Ambrogi Mário Jorge Campos dos Santos Marcelo Braga Bueno Guerra Edenir Rodrigues Pereira-Filho 《Soil biology & biochemistry》2012,44(1):21-25
Leaf-cutting ants perform a vital role in the cycling of carbon and nutrients in tropical ecosystems. Nests have high levels of organic matter and refuse dumps host up to two times more soil micro-organisms than non-nest soil. The increased levels of organic matter in the soil of nests, however, can affect CO2 emissions from soil and alter the balance of atmospheric CO2. We aimed at assessing the effect of nests of the leaf-cutting ant Acromyrmex balzani on CO2 emissions in a coastal area of Northeast Brazil. Results show that A. balzani nests emitted up to four times more CO2 than the surrounding soil and emissions were positively correlated with soil moisture and soil organic matter (SOM) content. In addition, field experiments demonstrated that refuse material has a lower residence time than the leaf material brought to the colonies. Despite the high density of nests and high content of SOM compared to adjacent control soil, CO2 emissions by A. balzani nests represent only 0.3% of the total CO2 efflux by the studied ecosystem. Although these effluxes account for a relative small portion of the total soil CO2 emission, they are still important for the understanding of C balance, especially when one considers the thousands of tons of CO2 emitted each day, across entire Neotropical regions where leaf-cutting ants occur. 相似文献
997.
Breno Tenório Leite Nicolle Figueira Robaina Luis Gustavo Teixeira dos Reis Annibal Duarte Pereira Netto Ricardo Jorgensen Cassella 《Water, air, and soil pollution》2012,223(3):1303-1313
The present work describes a detailed study about the adsorption of malachite green (MG) by a polyether-type polyurethane
foam (PUF) using sodium dodecylsulfate (SDS) as a carrier. The adsorption process was based on the formation of a hydrophobic
ionic-pair between the MG cationic dye and the dodecylsulfate anion, which presented high affinity for the PUF. The manifold
employed in the study was built up by adjusting a cylinder of PUF with 200 mg in the arm of an overhead stirrer, which was
soaked (and stirred) in the solution containing the dye and SDS. The adsorption process was characterized in relation to equilibrium
and kinetic aspects. Langmuir (r
2 = 0.842) and Freundlich (r
2 = 0.996) isotherms were also employed for modeling the system as well as the Nernst partition law (r
2 = 0.999). A study about the recovery of MG and the PUF regeneration was conducted, and the acetonitrile was the most efficient
solvent for the desorption of the adsorbed ionic pair. The obtained results showed that the concentration of SDS added to
the medium plays an important role on the adsorption process, which can be better described by employing a second-order kinetic
model. 相似文献
998.
Kátia R. Duarte Ana C. Freitas Ruth Pereira Jorge C. Pinheiro Fernando Gon?alves H. Azaari Mohammed El Azzouzi Abdallah Zrineh Souad Zaydoun Armando C. Duarte Teresa A. P. Rocha-Santos 《Water, air, and soil pollution》2012,223(7):4307-4318
Olive oil mill wastewater (OMW) generates a wide variety of pollutants depending on the production process and other factors such as olive varieties and cultivation system. Efforts to mitigate the impact of these effluents in the environment have been made by developing more efficient treatment systems in terms of removal of chemical oxygen demand (COD), color, organic compounds, and toxicity. This study is the first that reports the potential of a treatment of OMW by biocomposites of silica?Calginate?Cfungi (Pleurotus sajor caju and Trametes versicolor). The treatment by biocomposites can be considered as a three-step process responsible for the removal of the compounds: (1) adsorption of reactants on the monolithic structure and diffusion to the biological active sites, (2) biodegradation by the fungi, and (3) diffusion of the products resulting from the biodegradation. Both treatments tested showed potential capacity to remove organic compounds, color, COD, and toxicity. The T. versicolor biocomposites were the most effective and responsible for the reduction in color (from 38.4 to 44.9?%), COD (from 42.8 to 63.8?%), and total phenolic content (from 85.3 to 88.7?%) after 29?days of treatment. The toxicity reduction on Portuguese OMW was minimal, but the use of composites on the Moroccan OMW caused a 9.5- to 19-fold reduction in toxicity. Furthermore, the biocomposites showed potential for re-utilization for more 29?days of treatment. 相似文献
999.