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991.
992.
Soybean bacterial spot disease caused by Pseudomonas syringae pv.Glycinea which is a bacterial disease seriously affects soybean yield.Ten soybean germplasms and recombinant inbred lines (RILs) population were used to identify the resistant trait after inoculated with P.sg (P.sgneau001) in this study.High-density genetic mapping was obtained by specific length amplified fragment sequencing (SLAF-seq) of 149 RILs population which was derived from the crossing between Charleston and Dongnong594.The results indicated that 10 germplasm resources had four resistant germplasms included highly resistant cultivar Charleston,four susceptible varieties included Dongnong594 and two moderately resistant cultivars.Five quantitative trait locus (QTLs) were detected in RILs population by the composite interval mapping (CIM) method,and located on Linkage Group (LG) D1b (chromosome two),LG C2 (chromosome six) and LG H (chromosome 12),respectively.LOD scores ranged from 2.68 to 4.95 and the phenotypic variation percentage was from 6% to 11%.Six candidate genes were detected,according to the result of gene annotation information.Four of them had relationship with protein kinase activity,protein phosphorylation and leucine rich repeat (LRR) transmembrane protein,which had high expression after inoculated with P.sg by qRT-PCR. 相似文献
993.
994.
引进模糊向量空间的不变子空间的定义,研究了在模糊变换下的模糊向量空间的不变子空间的性质. 相似文献
995.
森林生态资源价值补偿机制的探讨 总被引:3,自引:1,他引:2
笔者在相关研究成果的基础上,对建立森林生态资源价值补偿机制所涉及到的有关问题进行了讨论,提出了价值补偿的4种途径,即自我补偿、行业补偿、社会补偿以及国家和地方补偿等;指出了森林生态资源价值补偿的具体办法和措施,这些办法和措施带有明显的过渡性质,并呈现多样化趋势;针对湖北森林生态资源价值补偿工作的现状,提出了建立补偿机制的应对策略,“局部补偿带动全面补偿”,“先易后难,分步实施”等是应对策略的核心;强调全社会广泛的参与和积极配合,是补偿机制能否顺利建立及有效运行的关键,只有调动全社会的力量,资源价值补偿的目的才能最终实现。 相似文献
996.
997.
建设和完善动物防疫体系,提高动物疫病的防控能力,是实现畜牧业健康稳定发展的前提.《中共中央关于制定国民经济和社会发展第十四个五年规划和二〇三五年远景目标的建议》提出:健全动物防疫和农作物病虫害防治体系,为建立健全新型动物防疫体系强化的政策基础.本文重点从机构设置、人员结构、工资待遇等层面阐述了机构改革后动物防疫体系的发... 相似文献
998.
Butyrolactone I (BTL-I) is a butanolide isolated from the deep-sea-derived fungus, Aspergillus sp. It provides a potential new target for the prevention and treatment of food allergies. This study aimed to investigate the metabolic and pharmacokinetic profile of BTL-I in rats. The metabolic profiles were obtained by UHPLC–Q-TOF-MS. As a result, eleven metabolites were structurally identified, and the proposed metabolic pathways of BTL-I were characterized. The main metabolites were the oxidative and glucuronidative metabolites. In addition, a sensitive UHPLC–MS/MS method was established for the quantitation of BTL-I in rat plasma (LOQ = 2 ng/mL). The method was fully validated and successfully applied to the pharmacokinetic study of BTL-I in rats after oral administration or intravenous administration. The oral bioavailability was calculated as 6.29%, and the maximum plasma concentrations were 9.85 ± 1.54 ng/mL and 17.97 ± 1.36 ng/mL for intravenous and intragastric dosing groups, respectively. 相似文献
999.
Xu-Xiu Lu Yao-Yao Jiang Yan-Wei Wu Guang-Ying Chen Chang-Lun Shao Yu-Cheng Gu Ming Liu Mei-Yan Wei 《Marine drugs》2022,20(1)
Brefeldin A (1), a potent cytotoxic natural macrolactone, was produced by the marine fungus Penicillium sp. (HS-N-29) from the medicinal mangrove Acanthus ilicifolius. Series of its ester derivatives 2–16 were designed and semi-synthesized, and their structures were characterized by spectroscopic methods. Their cytotoxic activities were evaluated against human chronic myelogenous leukemia K562 cell line in vitro, and the preliminary structure–activity relationships revealed that the hydroxy group played an important role. Moreover, the monoester derivatives exhibited stronger cytotoxic activity than the diester derivatives. Among them, brefeldin A 7-O-2-chloro-4,5-difluorobenzoate (7) exhibited the strongest inhibitory effect on the proliferation of K562 cells with an IC50 value of 0.84 µM. Further evaluations indicated that 7 induced cell cycle arrest, stimulated cell apoptosis, inhibited phosphorylation of BCR-ABL, and thereby inactivated its downstream AKT signaling pathway. The expression of downstream signaling molecules in the AKT pathway, including mTOR and p70S6K, was also attenuated after 7-treatment in a dose-dependent manner. Furthermore, molecular modeling of 7 docked into 1 binding site of an ARF1–GDP-GEF complex represented well-tolerance. Taken together, 7 had the potential to be served as an effective antileukemia agent or lead compound for further exploration. 相似文献
1000.