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141.
大豆新品种“苏豆9号”选育与栽培技术研究 总被引:1,自引:0,他引:1
“苏豆9号”为东海县农业科学研究所经有性杂交,系谱法选育而成的新品种,具有早熟、高产、优质、抗倒伏、抗病性强,抗逆性强,适应性广等特点.2008-2010年参加江苏省区试,3年平均184.8 kg/667 m 2,较对照徐豆13增产3.6%,2010年增产极显著.2011年生产试验平均177.5 kg/667 m2,较对照增产6.7%;2012年3月通过江苏省农作物品种审定委员会审定通过,适宜江苏省淮北地区作夏大豆种植.为探讨适宜播期,最佳种植密度和合理的施肥量,特设栽培试验,结果表明,苏豆9号最佳播种期是6月上中旬,在此范围内越早越好,最佳密度是1.4万株/667 m2,基肥用量以含氮、磷、钾45%复合肥20 kg/667 m2为宜. 相似文献
142.
Negligible contribution from roots to soil-borne phospholipid fatty acid fungal biomarkers 18:2ω6,9 and 18:1ω9 总被引:1,自引:0,他引:1
The phospholipid fatty acid biomarkers 18:1ω9, 18:2ω6,9 and 18:3ω3,6,9 are commonly used as fungal biomarkers in soils. They have, however, also been found to occur in plant tissues, such as roots. Thus, the use of these PLFAs as fungal biomarkers in sieved soil, which may still contain small remains of roots, has been questioned. We used data from a recent beech tree girdling experiment to calculate the contribution of roots to these biomarkers and were able to demonstrate that not more than 0.61% of 18:1ω9 and 18:2ω6,9 in sieved soil samples originated from roots (but 4% of 18:3ω3,6,9). Additionally, the abundance of the biomarker 18:2ω6,9 in the soil was found to be highly correlated to ectomycorrhizal root colonization, which further corroborates its fungal origin. PLFA biomarkers were substantially reduced in vital roots from girdled trees compared to roots of control trees (by up to 76%), indicating that the major part of PLFAs measured in roots may actually originate from ectomycorrhizal fungi growing inside the roots. We calculated, that even a near to 50% reduction in fine root biomass - as observed in the girdling treatment - accounted for only 0.8% of the measured decrease of 18:2ω6,9. Our results demonstrate that both 18:1ω9 and 18:2ω6,9 are suitable biomarkers for detecting fungal dynamics in soils and that especially 18:2ω6,9 is a reliable biomarker to study mycorrhizal dynamics in beech forests. 相似文献
143.
介绍了基于ARM920T内核的嵌入式控制系统的设计与实施,并将控制系统引入设施栽培自动灌溉控制中。实践证明,该系统的设计达到了预期的效果。 相似文献
144.
145.
本文主要对9CrSi材料的焊接工艺性能进行分析,考虑冲压模具的特点,提出合适的焊补工艺,减少了模具局部缺损而报废的损失,降低了冲压的生产成本. 相似文献
146.
Chisato YONEMOCHI Takuo IKEDA Chisato HARADA Toyoko KUSAMA Michito HANAZUMI 《Animal Science Journal》2003,74(2):81-88
The influence of transgenic event CBH 351 (Starlink)-derived hybrid corn (SL) on the health condition, physiological function and lactational performance of dairy cows as well as the transfer of the cry9C gene and Cry9C protein present in SL to milk, blood, liver and muscles was examined, and compared with a diet containing non-transgenic (isogenic) control corn (non-SL). After adapting to a diet containing non-SL for 2 weeks, four Holstein cows were assigned to each of the non-SL and SL groups and were fed diets containing non-SL or SL, respectively, for 5 weeks. There were no significant influences on the physiological condition, milk yield or serum biochemical and hematological values after feeding with SL. There was also no influence on pH value, cell density of protozoa, or volatile fatty acid concentration and composition of rumen fluids. In addition, no significant differences were observed on histopathological examination of the major organs and tissues between the SL and non-SL groups. Moreover, the cry9C gene and Cry9C protein were not detected by the polymerase chain reaction method and ELISA in the milk, blood, liver and muscles of the cows at the end of the experiment. 相似文献
147.
148.
F. Madec J. M. Gourreau C. Kaiser J. Le Dantec P. Vannier M. Aymard 《Comparative immunology, microbiology and infectious diseases》1985,8(3-4)
Une 9;tude est mise en place dans un groupe de 16 9;levages intensifs venant de connaitre une attaque grippale et pratiquant à la fois le naissage et l'engraissement dans la r9;gion de Bretagne (France). L'objet de cette 9;tude est de mettre en 9;vidence une activit9; du virus grippal au sein des 9;levages en dehors des vagues 9;pid9;miques. Dans chaque 9;levage, 2 lots de porcelets sont individuellement suivis depuis la phase d'allaitement jusqu'à l'abattage. Des contrôles s9;rologiques mensuels sont pratiqu9;s en vue de suivre l'9;volution des anticorps grippaux ainsi que ceux de la maladie d'Aujeszky. En outre des 9;couvillonnages nasaux et des pr9;lèvements de poumons sont r9;alis9;s en vue de recherches virales. Ces travaux sont accompagn9;s par la collecte de renseignements 9;pid9;miologiques dans chacun des 9;levages. Les anticorps grippaux d'origine colostrale inhibant l'h9;magglutination d9;croissent assez rapidement chez le porcelet. Par la suite une conversion s9;rologique est observ9;e sur près de 10% des animaux suivis. Les animaux concern9;s appartiennent à 4 des 16 9;levages. La s9;roconversion intervient g9;n9;ralement après 3 mois d'âge. Aucun isolement viral n'a pu être r9;alis9;. Certaines conditions semblent associ9;es à la persistance d'une activit9; virale comme la d9;mographie d9;s9;quilibr9;e du troupeau de truies, la conduite en continu de la porcherie d'engraissement, la pr9;existence d'une pathologie respiratoire s9;vère. Une s9;roconversion Aujeszky est 9;galement observ9;e dans 3 des 4 9;levages concern9;s par l'activit9; du virus grippal. 相似文献
149.
Rabies is an enzootic viral disease widespread throughout the world. Although it is a vaccine-preventable disease, the annual number of human deaths caused by rabies is estimated to be 32,000 in Asia. Phylogenetic analysis based on sequence data of the partial N gene of rabies viruses in Asia has shown that the viruses are divided into five genogroups, distributed in Middle East, South Asia, South East Asia, Malay, and Arctic regions. The genetic relationships among these rabies viruses agree basically with the results of previous studies. Meanwhile, new types of vaccines are being developed by applying gene manipulation techniques to rabies virus in order to overcome the disadvantages of current vaccines. This article reviews the molecular epidemiology of rabies in Asia and progress made in the development of new-generation rabies vaccines with the goal of elimination or control of rabies in Asia. 相似文献
150.
Halpin K Mungall BA 《Comparative immunology, microbiology and infectious diseases》2007,30(5-6):287-307
Following the discovery of two new paramyxoviruses in the 1990s, much effort has been placed on rapidly finding the reservoir hosts, characterising the genomes, identifying the viral receptors and formulating potential vaccines and therapeutic options for these viruses, Hendra and Nipah viruses caused zoonotic disease on a scale not seen before with other paramyxoviruses. Nipah virus particularly caused high morbidity and mortality in humans and high morbidity in pig populations in the first outbreak in Malaysia. Both viruses continue to pose a threat with sporadic outbreaks continuing into the 21st century. Experimental and surveillance studies identified that pteropus bats are the reservoir hosts. Research continues in an attempt to understand events that precipitated spillover of these viruses. Discovered on the cusp of the molecular technology revolution, much progress has been made in understanding these new viruses. This review endeavours to capture the depth and breadth of these recent advances. 相似文献