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981.
目的 探讨甘露聚糖结合凝集素(Mannan-binding lectin,MBL)对CD11c+髓样树突状细胞(CD11c+mDC)表型和功能的影响.方法 应用磁珠分选技术获得BALB/c小鼠脾脏CD1 1c+ mDC和CD4+T淋巴细胞.在CD11c+mDC中加入不同浓度的MBL(2.5~20 μg/mL)刺激,以不加MBL的细胞作为对照,应用ELISA法检测细胞培养上清液中的IL-12水平,流式细胞仪检测细胞表面分子CD40、CD80、CD86及HLA-DR的表达.用MTT法测定CD11c+mDC刺激CD4+T淋巴细胞的增殖能力.ELISA法检测细胞培养液中IL-4和IFN-γ水平.结果 MBL显著增强CD11c+mDC表面分子CD40、CD80、CD86及HLA-DR的表达和IL-12的分泌,促进CD4+T淋巴细胞的增殖和抗原递呈能力,诱导CD4+T向TH1反应分化.结论 MBL能够有效刺激CD11c+mDC的活化,诱导CD4+T淋巴细胞向TH1反应分化. 相似文献
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986.
中国天然林资源保护工程综合评价指标体系与评估方法 总被引:1,自引:0,他引:1
天然林资源是国家重要的战略资源与生态资源,在维护国土生态安全、应对气候变化、保护生物多样性等方面发挥着不可替代的重要作用。作为覆盖范围最广、投资规模最大的天然林资源保护工程(简称天保工程)自2000年正式启动以来,对长江上游、黄河上中游地区以及东北、内蒙古、新疆、海南等重点国有林区的森林资源保护修复、区域生态环境改善及经济社会可持续发展等多方面都产生了巨大、深远影响。天保工程二期于2020年结束,全面定量评估天保工程的生态、经济和社会综合效益和国内外的巨大影响,可为全面推进我国天然林资源保护修复提供科技支撑,为后续政策修订提供决策依据。本文基于空间信息技术、样地调查、生态站观测、比较分析等手段,构建了适用于天保工程的综合评价指标体系与评估方法,涵盖森林资源、生态效益、社会经济效益、生态修复措施和政策设计5个方面,对全面贯彻落实国家生态文明战略和《天然林保护修复制度方案》具有重要的现实意义和深远历史意义,为开展全国性的重大生态工程评估提供借鉴和参考。 相似文献
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Key message
Salt-induced phosphorylation of MdVHA-B1 protein was mediated by MdSOS2L1 protein kinase, and thereby increasing malate content in apple.Abstract
Salinity is an important environmental factor that influences malate accumulation in apple. However, the molecular mechanism by which salinity regulates this process is poorly understood. In this work, we found that MdSOS2L1, a novel AtSOS2-LIKE protein kinase, interacts with V-ATPase subunit MdVHA-B1. Furthermore, MdSOS2L1 directly phosphorylates MdVHA-B1 at Ser396 site to modulate malate accumulation in response to salt stress. Meanwhile, a series of transgenic analyses in apple calli showed that the MdSOS2L1–MdVHAB1 pathway was involved in the regulation of malate accumulation. Finally, a viral vector-based transformation approach demonstrated that the MdSOS2L1–MdVHAB1 pathway also modulated malate accumulation in apple fruits with or without salt stress. Collectively, our findings provide a new insight into the mechanism by which MdSOS2L1 phosphorylates MdVHA-B1 to modulate malate accumulation in response to salinity in apple.988.
Amrita Saxena Richa Raghuwanshi Harikesh Bahadur Singh 《Journal of Plant Growth Regulation》2016,35(2):377-389
Biocontrol strategies have been mainly focused on proposing the use of biocontrol agents (BCAs) isolated from the rhizospheric region of the plant for protection against phytopathogens. The present study evaluates the effectiveness of phyllospheric Trichoderma isolates in elevating the defense responses in chilli against Colletotrichum capsici infection and comparing its efficiency to the conventionally recommended rhizospheric Trichoderma strains. The elicitation of the defense network in the plants was analyzed using biochemical assays for important enzymes, that is, PAL, PO, PPO, TPC, SOD along with the total protein level in challenged plants over untreated and unchallenged control plants. The results recorded 2.1, 5.18, 3, 0.67, and 0.5-fold increases in TPC, PAL, PO, PPO, and total protein content in BHUF4 (phyllopsheric Trichoderma isolate)-treated plants when compared to control plants under C. capsici challenge. This was at par with the increment recorded in T16A (rhizospheric Trichoderma isolate)-treated chilli plants. The increment in growth parameters was also recorded after treatment with the isolated Trichoderma strains. Interestingly, the phyllospheric isolate (BHUF4) treatment recorded comparable growth promotion in chilli plants recording 36, 62, and 60 % increases in one of the major parameters of plant growth, that is, root length, no. of leaves, and dry weight, respectively. This study proposes the use of combined application of both rhizospheric as well as phyllospheric Trichoderma isolates for better and all around protection of plants against foliar as well as soil phytopathogens. This would be a novel approach in biological control strategy for better management of anthracnose disease of chilli. 相似文献
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Jing Gao Guoji Liu Hongping Li Li Xu Lili Du Bo Yang 《Bioprocess and biosystems engineering》2016,39(7):1115-1127
Anaerobic digestion (AD) is widely used in treating the sewage sludge, as it can reduce the amount of sludge, eliminate pathogens and produce biofuel. To enhance the operational performance and stability of anaerobic bioreactors, operational and conventional chemical data from full-scale sludge anaerobic digesters were collected over a 2-year period and summarized, and the microbial community diversity of the sludge sample was investigated at various stages of the AD process. For the purpose of distinguishing between the functional and community diversity of the microbes, Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) software was used to impute the prevalence of 16S rDNA marker gene sequences in the difference in various sludge samples. Meanwhile, a taxa analysis was also carried out to investigate the different sludge samples. The microbial community diversity analysis of one AD sludge sample showed that the most dominant bacterial genera were Saccharicrinis, Syntrophus, Anaerotruncus and Thermanaerothrix. Among archaea, acetoclastic Methanosaeta represented 56.0 %, and hydrogenotrophic Methanospirillum, Methanoculleus, Methanothermus and Methanolinea accounted for 41.3 % of all methanogens. The taxa, genetic and functional prediction analyses of the feedstock and AD sludge samples suggested great community diversity differences between them. The taxa of bacteria in two AD sludge samples were considerably different, but the abundances of the functional KEGG pathways took on similar levels. The numbers of identified pathogens were significantly lower in the digested sludge than in the feedstock, but the PICRUSt results showed the difference in “human diseases” abundances in the level-1 pathway between the two sludge samples was small. 相似文献
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Mei-Juan Tan Xi Chen Yu-Kuan Wang Guang-Lei Liu Zhen-Ming Chi 《Bioprocess and biosystems engineering》2016,39(8):1289-1296
In this study, after the expression of a pyruvate carboxylase gene (PYC) cloned from Meyerozyma guilliermondii in a marine-derived yeast Yarrowia lipolytica SWJ-1b, a transformant PG86 obtained had much higher PYC activity than Y. lipolytica SWJ-1b. At the same time, the PYC gene expression and citric acid (CA) production by the transformant PG86 were also greatly enhanced. When glucose concentration in the medium was 60.0 g L?1, CA concentration formed by the transformant PG86 was 34.02 g L?1, leading to a CA yield of 0.57 g g?1 of glucose. During a 10-L fed-batch fermentation, the final concentration of CA was 101.0 ± 1.3 g L?1, the yield was 0.89 g g?1 of glucose, the productivity was 0.42 g L?1 h?1 and only 5.93 g L?1 reducing sugar was left in the fermented medium within 240 h of the fed-batch fermentation. HPLC analysis showed that most of the fermentation products were CA. 相似文献