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961.
A monophasic strain of Salmonella group B having the antigenic structure 4, 12: a: - was isolated in culture from various tissues of 39 harbour porpoises (Phocoena phocoena). The tissue from which the organism was recovered most frequently was lung in 33 animals and intestine in 16 animals, but it was also isolated from heart valve, liver, kidney, spleen, mesenteric lymph node, pulmonary lymph node, hepatic lymph node, urethra, sheath and epididymis. As far as we are aware this is the first record of this strain from an animal source, raising the possibility that it may be host-adapted to harbour porpoises. The possible modes of transmission of monophasic group B Salmonella between porpoises are discussed. 相似文献
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Viktor V. Husak Nadia M. Mosiichuk Olga I. Kubrak Tetiana M. Matviishyn Janet M. Storey Kenneth B. Storey Volodymyr I. Lushchak 《Fish physiology and biochemistry》2018,44(3):841-852
Copper is an essential element, but at high concentrations, it is toxic for living organisms. The present study investigated the responses of goldfish, Carassius auratus, to 96 h exposure to 30, 300, or 700 μg L?1 of copper II chloride (Cu2+). The content of protein carbonyls was higher in kidney (by 158%) after exposure to 700 mg L?1 copper, whereas in gills, liver, and brain, we observed lower content of protein carbonyls after exposure to copper compared with control values. Exposure to copper resulted in increased levels of lipid peroxides in gills (76%) and liver (95–110%) after exposure to 300 and 700 μg L?1 Cu2+. Low molecular mass thiols were depleted by 23–40% in liver and by 29–67% in kidney in response to copper treatment and can be used as biomarkers toxicity of copper. The activities of primary antioxidant enzymes, superoxide dismutase and catalase, were increased in liver as a result of Cu2+ exposure, whereas in kidney catalase activity was decreased. The activities of glutathione-related enzymes, glutathione peroxidase, glutathione-S-transferase, and glutathione reductase were decreased as a result of copper exposure, but glutathione reductase activity increased by 25–40% in liver. Taken together, these data show that exposure of fish to Cu2+ ions results in the development of low/high intensity oxidative stress reflected in enhanced activities of antioxidant and associated enzymes in different goldfish tissues. 相似文献
963.
The single-scan setup of terrestrial laser scanning of a forest field plot has advantages compared to the multi-scan setup: the speed of operation and that there is no need of a co-registration of the different scans. However in a single-scan setup some of the trees are shaded by others and therefore not detected in the scan. A field inventory solution must take this fact into account. This simulation study shows how different plot sizes and tree stand densities influence the stem visibility giving nonlinear effects especially for large trees and high stem numbers. These effects can be counteracted by using an edge or center stem point detection criteria when analyzing the results or by weighting the detected trees by their visibility. It is shown that the stem density and diameter distribution can be estimated from the visible areas of the plot in case the stem positions are Poisson distributed. 相似文献
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Retrospective evaluation of and risk factor analysis for presumed fluid overload in cats with urethral obstruction: 11 cases (2002–2012) 下载免费PDF全文
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Mumuni Abudulai Jesse Naab Shaibu Seidu Seini Israel Dzomeku Kenneth Boote Rick Brandenburg 《国际虫害防治杂志》2018,64(3):204-209
Weeds and diseases can reduce peanut (Arachis hypogaea L.) yield or increase cost of production to maintain acceptable yield. While herbicides and fungicides have limited availability in many areas of Ghana and currently are too expensive for resource-poor farmers, control by these pesticides can have a major positive impact on peanut yield. Field experiments were conducted during the rainy seasons of 2009 and 2010 in northern Ghana to determine the effects of herbicide and hand weeding in combination with fungicides on pest management and peanut yield. Peanut pod yield was often more highly correlated with disease severity and canopy defoliation resulting from early leaf spot (caused by Cercospora arachidicola Hori) and late leaf spot (caused by Cercosporidium personatum (Berk. & M.A. Curtis) Deighton) than weed biomass. In some instances, less disease and canopy defoliation were observed when weeds were not controlled effectively compared with increased weed management through hand weeding or herbicide. Two hand weedings or applying pendimethalin preemergence with one hand weeding in combination with 4 applications of triadimefon and chlorothalonil resulted in the lowest weed density and canopy defoliation and often resulted in the highest peanut yield. 相似文献
969.
Julia Bally Elane Fishilevich Andrew J Bowling Heather E Pence Kenneth E Narva Peter M Waterhouse 《Pest management science》2018,74(8):1751-1758
RNA interference (RNAi) was discovered almost 20 years ago and has been exploited worldwide to silence genes in plants and animals. A decade later, it was found that transforming plants with an RNAi construct targeting an insect gene could protect the plant against feeding by that insect. Production of double‐stranded RNA (dsRNA) in a plant to affect the viability of a herbivorous animal is termed trans‐kingdom RNAi (TK‐RNAi). Since this pioneering work, there have been many further examples of successful TK‐RNAi, but also reports of failed attempts and unrepeatable experiments. Recently, three laboratories have shown that producing dsRNA in a plant's chloroplast, rather than in its cellular cytoplasm, is a very effective way of delivering TK‐RNAi. Our review examines this potentially game‐changing approach and compares it with other transgenic insect‐proofing schemes. © 2018 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
970.
Wheat genetic resources enhancement by the International Maize and Wheat Improvement Center (CIMMYT) 总被引:1,自引:0,他引:1
Rodomiro Ortiz Hans-Joachim Braun José Crossa Jonathan H. Crouch Guy Davenport John Dixon Susanne Dreisigacker Etienne Duveiller Zhonghu He Julio Huerta Arun K. Joshi Masahiro Kishii Petr Kosina Yann Manes Monica Mezzalama Alexei Morgounov Jiro Murakami Julie Nicol Guillermo Ortiz Ferrara J. Iván Ortiz-Monasterio Thomas S. Payne R. Javier Peña Matthew P. Reynolds Kenneth D. Sayre Ram C. Sharma Ravi P. Singh Jiankang Wang Marilyn Warburton Huixia Wu Masa Iwanaga 《Genetic Resources and Crop Evolution》2008,55(7):1095-1140
The International Maize and Wheat Improvement Center (CIMMYT) acts as a catalyst and leader in a global maize and wheat innovation
network that serves the poor in the developing world. Drawing on strong science and effective partnerships, CIMMYT researchers
create, share, and use knowledge and technology to increase food security, improve the productivity and profitability of farming
systems and sustain natural resources. This people-centered mission does not ignore the fact that CIMMYT’s unique niche is
as a genetic resources enhancement center for the developing world, as shown by this review article focusing on wheat. CIMMYT’s
value proposition resides therefore in its use of crop genetic diversity: conserving it, studying it, adding value to it,
and sharing it in enhanced form with clients worldwide. The main undertakings include: long-term safe conservation of world
heritage of both crop resources for future generations, in line with formal agreements under the 2004 International Treaty
on Plant Genetic Resources for Food and Agriculture, understanding the rich genetic diversity of two of the most important
staples worldwide, exploiting the untapped value of crop genetic resources through discovery of specific, strategically-important
traits required for current and future generations of target beneficiaries, and development of strategic germplasm through
innovative genetic enhancement. Finally, the Center needs to ensure that its main products reach end-users and improve their
livelihoods. In this regard, CIMMYT is the main international, public source of wheat seed-embedded technology to reduce vulnerability
and alleviate poverty, helping farmers move from subsistence to income-generating production systems. Beyond a focus on higher
grain yields and value-added germplasm, CIMMYT plays an “integrative” role in crop and natural resource management research,
promoting the efficient use of water and other inputs, lower production costs, better management of biotic stresses, and enhanced
system diversity and resilience. 相似文献