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991.
四川农村养猪日粮及平衡饲养技术初探 总被引:1,自引:0,他引:1
在四川养猪主产地的不同地理生态区选点,深入农户广泛开展农村养猪常用饲料及日粮调研,采集饲料样品92个,分析测定铁、铜、猛、锌、钴、碘和硒的含量,将四川农村养猪日粮总结划分为:(1)玉米、青料日粮;(2)甘薯、青料日粮;(3)玉米、小麦、青料日粮;(4)玉米、大麦、青料日粮。并对各日粮的营养含量作了概算和评定。在此基础上,提出适合四川农村养猪日粮的添加剂预混料和浓缩料配制建议以及浓缩料主要营养指标推荐值。依此,开展了4种日粮的6批44组347头肉猪的饲养试验。从中优选出一批饲料配方,已在11个地市的40余家厂试产,省内外广大农村养猪中应用,有效地促进了饲料工业和农村养猪生产的发展。研制的甘薯青料日粮及平衡饲养技术,已列专题在省内大面积推广应用。经济效益和社会效益十分显著。 相似文献
992.
993.
选用6只小尾寒羊泌乳母羊,通过饲养试验、消化代谢试验、比较屠宰试验等手段,研究其蛋白质需要量。结果表明,小尾寒羊泌乳母羊代谢粪氮(MFN)和内源尿氮(EUN)的排出量分别为0.1312和0.13459/kg·W0.75·d。小尾寒羊泌乳期维持可消化粗蛋白需要量为1.51W0.75g/d,每产1kg奶需可消化粗蛋白829。小尾寒羊泌乳母羊的可消化粗蛋色总需要量(RDCP,g/d),可按下式求得:RDCP=1.51W0.75+82MP式中:W0.75——代谢体重,kg;MP——为产奶量,kg。 相似文献
994.
武威地区天然草地有毒植物及其防除 总被引:12,自引:2,他引:10
对武威地区天然草地有毒植物的种类,分布及其对草地的危害情况进行了调查研究,结果表明,全区天然草地共有毒植物172号,分属31科84属,平均2.15种/m^2,盖度达4.41%地上部分生物量11.28g/m^2。对草地危害的主要黄花棘豆,甘肃棘豆,小花棘豆,狼毒和马草,受侵害的草地主要是山地草甸和山地草原,通过分析,提出了有毒植物防除和利用的建议。 相似文献
995.
该文在介绍农业工程技术内涵的基础上,论述了农业工程在我国全面建设小康社会的中的作用,作者认为农业工程是我国产业结构调整的重要依据,是信息技术应用的广阔天地,是生物技术转化为社会生产力的工程手段,是提高农民素质的技术依托,是我国全面建设小康社会,解决"三农"问题的技术关键.并由此提出了发展农业工程事业的几点建议1)农业工程从业人员充分珍惜本学科在我国全面建设小康社会中的历史作用;2)加速研究开发和集成组装生态的和经济的农业工程适用技术; 3)以农业工程适用技术为依托,加大对农业工程生产资料的投资力度;4)设立农业工程的行政管理部门,充分发挥行政管理部门的服务功能;5)在发展公司或公司加农户的科技农业园区的同时,发展以农户为基础进行集体化的组织和运行体系的研究,并在大学增设农业工程管理专业;6)大力发展以大学专科为基础的农业工程教育体系和进行农业工程教育学的研究. 相似文献
996.
Human cerebral cortical function degrades during old age. Much of this change may result from a degradation of intracortical inhibition during senescence. We used multibarreled microelectrodes to study the effects of electrophoretic application of gamma-aminobutyric acid (GABA), the GABA type a (GABAa) receptor agonist muscimol, and the GABAa receptor antagonist bicuculline, respectively, on the properties of individual V1 cells in old monkeys. Bicuculline exerted a much weaker effect on neuronal responses in old than in young animals, confirming a degradation of GABA-mediated inhibition. On the other hand, the administration of GABA and muscimol resulted in improved visual function. Many treated cells in area V1 of old animals displayed responses typical of young cells. The present results have important implications for the treatment of the sensory, motor, and cognitive declines that accompany old age. 相似文献
997.
998.
Xiao-Bing Wu Yi-Quan WangKai-Ya Zhou Wei-Quan ZhuJi-Shan Nie Chao-Lin WangWan-Shu Xie 《Biological conservation》2002,106(3):435-441
Chinese alligator (Alligator sinensis) is an endemic species in China. The likely extinction of it in the wild has been recognised. To prevent this species becoming extinct, the Anhui Research Centre of Chinese Alligator Reproduction (ARCCAR) was established in Xuanzhou, Anhui Province in 1979, where has been established the largest captive population of Chinese alligator (XZSP) in the world. Another farm (CXSP) was established by villagers in Changxin, Zhejiang Province. The results of an investigation of the two captive subpopulation structures by genetic analysis are presented in this paper. We examined the genetic variation in the two captive subpopulations using RAPDs. Thirty-one random primers were selected among 199 random primers screened. A total of 193 reproducible RAPD fragments were scored among 43 individuals, of which 21 (10.88%) were polymorphic. The genetic distances between 43 individuals ranged from 0 to 0.0376 with average of 0.0104±0.0055 S.E. The genetic similarity in CXSP (0.9948±0.0029 S.E.) was higher than that in XZSP (0.9894±0.0055 S.E.). The founder effect is a possible explanation for very low genetic variation in CXSP. Analysis of the RAPD data showed that the mean phenotypic band frequencies of each polymorphic loci was 0.6656±0.3730 S.E. The lowest phenotypic band frequency (0.0233) was found in four of those polymorphic loci. There was no genetic difference between the two subpopulations (Dij=0.0009). According to the dendrogram and the distribution of polymorphic fragments in two subpopulations, CXSP originated genetically from XZSP. This paper summarises a preliminary research on genetic structure in populations of Chinese alligator. Although there is higher genetic similary (0.9896±0.0055 S.E.) in captive population of A. sinensis, we did not determine whether or not loss of genetic variation had occurred in relation to a wild control population. The data of malformed offspring will be collected carefully, and wild samples be added to set up a control population in future study. 相似文献
999.
Clavijo A Munroe F Zhou EM Booth TF Roblesky K 《The Canadian veterinary journal. La revue veterinaire canadienne》2000,41(4):312-314
Bluetongue virus was isolated from a sentinel herd in British Columbia. Virus isolation was by intravenous inoculation of embryonated chicken eggs and subculture in BHK-21 cells. The cytopathic agent was identified as bluetongue virus by electron microscopy and the immunoperoxidase test. The serotype was identified as serotype 11 by virus neutralization. 相似文献
1000.
Two naturally occurring antioxidants, ascorbic acid and turmeric, were effective in inhibiting formation of hexanal, (E)-2-penenal, (E)-2-hexenal, (E)-2-heptenal, and (E)-2-octenal when slurries of fermented cucumber tissue were exposed to oxygen. Added ascorbic acid prevented formation of most of these oxidative aldehydes at 175 ppm or greater. Turmeric, which is used commercially as a yellow coloring in cucumber pickle products, was found to almost completely prevent aldehyde formation at 40 ppm. 相似文献