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191.
人降钙素基因相关肽转基因马铃薯的RT-PCR分析   总被引:3,自引:0,他引:3  
报道经过农杆菌介导将人降钙素基因相关肽(calcitoningenerelatedpeptide,CGRP)基因由马铃薯块茎专一表达classIpatatin基因5′侧翼区和CaMV35S启动子驱动构建的马铃薯表达载体导入马铃薯,PCR鉴定获得了转基因植株。RTPCR分析证实classIpatatin基因5′侧翼区驱动的CGRPmRNA在转基因马铃薯中的表达。研究结果在开发转基因马铃薯生物反应器表达医用多肽中具有重要意义。  相似文献   
192.
Pyrazole constitutes an important heterocyclic family covering a broad range of synthetic as well as natural products that exhibit numerous chemical, biological, agrochemical and pharmacological properties. In order to explore compounds with good fungicidal activity, a series of new pyrazole derivatives containing 5-phenyl-2-furan were designed and synthesized. In vitro and in vivo fungicidal activities were evaluated and the compound ethyl-1-(5-phenylfuran-2-carbonyl)-5-propyl-1H-pyrazole-3-carboxylate (I8) displayed significant fungicidal activity against various fungi, especially against P. infestans. The structures of the novel pyrazole derivatives were confirmed by 1H NMR, 13C NMR, MS, elemental analysis and X-ray single crystal diffraction. Further study showed that compound I8 might act on the synthesis of cell walls from morphological and ultrastructural studies by SEM and TEM. The results also revealed that compound I8 could block the nutritional transportation leading to cells senescence and death. These results suggested that the novel pyrazole derivatives proved to be promising lead compounds.  相似文献   
193.
The reliability and durability of lithium‐ion capacitors (LICs) are severely hindered by the kinetic imbalance between capacitive and Faradaic electrodes. Efficient charge storage in LICs is still a huge challenge, particularly for thick electrodes with high mass loading, fast charge delivery, and harsh working conditions. Here, a unique thermally durable, stable LIC with high energy density from all‐inorganic hydroxyapatite nanowire (HAP NW)‐enabled electrodes and separators is reported. Namely, the LIC device is designed and constructed with the electron/ion dual highly conductive and fire‐resistant composite Li4Ti5O12‐based anode and activated carbon‐based cathode, together with a thermal‐tolerant HAP NW separator. Despite the thick‐electrode configuration, the as‐fabricated all HAP NW‐enabled LIC exhibits much enhanced electrochemical kinetics and performance, especially at high current rates and temperatures. Long cycling lifetime and state‐of‐the‐art areal energy density (1.58 mWh cm?2) at a high mass loading of 30 mg cm?2 are achieved. Benefiting from the excellent fire resistance of HAP NWs, such an unusual LIC exhibits high thermal durability and can work over a wide range of temperatures from room temperature to 150 °C. Taking full advantage of synergistic configuration design, this work sets the stage for designing advanced LICs beyond the research of active materials.  相似文献   
194.
强度石漠化区不同植被修复模式下土壤螨类群落差异   总被引:1,自引:2,他引:1  
陈浒  金道超  陈航  王鹏举  周政  林丹丹 《生态学报》2018,38(19):7045-7056
石漠化治理区不同植被修复模式下的土壤螨类群落差异反映了生态系统的恢复状况,可籍以反映石漠化治理的生态效果。2014年1月、4月、8月和10月,对贵州花江喀斯特峡谷区顶坛小流域强度石漠化区域的"花椒"、"金银花"、"花椒+金银花"3种植被修复生境的土壤螨类进行了调查,共捕获土壤螨类1372头,隶属3目55科89属。采用类群(属)数、个体数量、个体密度、多样性指数(H')、丰富度指数(SR)、均匀性指数(J)、相似性指数(CN)、捕食性螨类成熟度指数(MI)和甲螨MGP类群等参数对土壤螨类群落差异进行了表征。结果显示,花椒林拥有较丰富的螨类属,金银花林拥有较高的的个体数量和个体密度。不同模式下的科、属类群组成呈现差异;属数、个体数量存在一定的季节差异,花椒林的螨类属数、金银花林的螨类个体数量和个体密度呈现一定的表聚性;群落多样性大多存在季节差异;捕食性革螨以r选择型为主,甲螨主要为O型和M型。研究表明,强度石漠化在不同植被修复模式下,土壤螨类生物生态类群存在差异,土壤生态系统仍处于修复之中,其中螨类优势属、具有典型生物学与生态学特性差异的螨类类群对石漠化治理的生态效果具有重要的指示作用。  相似文献   
195.
The MIND multiprotein complex is a conserved, essential component of eukaryotic kinetochores and is a constituent of the tripartite KMN network that directly attaches the kinetochore to the mitotic spindle. The primary microtubule-binding complex in this network, NDC80, has been extensively characterized, but very little is known about the structure or function of the MIND complex. In this study, we present biochemical, hydrodynamic, electron microscopy, and small-angle x-ray scattering data that provide insight into the overall architecture and assembly of the MIND complex and the physical relationship of the complex with other components of the KMN network. We propose a model for the overall structure of the complex and provide data on the interactions with NDC80, Spc105p, and thus the mitotic spindle.  相似文献   
196.
Chemerin is a novel chemokine that binds to the G protein-coupled receptor (GPCR) ChemR23, also known as chemokine-like receptor 1 (CMKLR1). It is secreted as a precursor and executes pro-inflammatory functions when the last six amino acids are removed from its C-terminus by serine proteases. After maturation, Chemerin attracts dendritic cells and macrophages through binding to ChemR23. We report a new method for expression and purification of mature recombinant human Chemerin (rhChemerin) using a prokaryotic system. After being expressed in bacteria, rhChemerin in inclusion bodies was denatured using 6 M guanidine chloride. Soluble rhChemerin was prepared by the protein-specific renaturation solution under defined conditions. It was subsequently purified using ion-exchange columns to more than 95% purity with endotoxin level <1.0 EU/μg. We further demonstrated its biological activities for attracting migration of human dendritic cells and murine macrophages in vitro using established chemotaxis assays.  相似文献   
197.
Adipose triglyceride lipase (ATGL) is a triglyceride hydrolysis lipase and is generally related to lipid metabolism in animals. The ATGL gene was well studied in mammals, however very less was known in birds that differed significantly with mammals for lipid metabolism. In this study, cloning, mRNA real time and association analysis was performed to characterize the ATGL gene in birds. Results showed that the obtained ATGL gene cDNA of parrot, quail, duck were 1,651 bp (NCBI accession number: GQ221784), 1,557 bp (NCBI accession number: GQ221783) and 1,440 bp each, encoded 481-, 482- and 279-amino acid (AA) peptide, respectively. The parrot ATGL (pATGL) gene was found to predominantly express in breast muscle and leg muscle, and very higher ATGL mRNA level was also found in heart, abdominal fat and subcutaneous fat. The quail ATGL (qATGL) gene was also predominantly expressed in breast muscle and leg muscle, and then to a much lesser degree in heart. The duck ATGL (dATGL) gene was found to predominantly express in subcutaneous fat and abdominal fat, quite higher ATGL mRNA was also found in heart, spleen, breast muscle and leg muscle. Blast analyses indicated the high homology of ATGL and its patatin region, and moreover, and the active serine hydrolase motif (“GASAG” for “GXSXG”) and the glycine rich motif (“GCGFLG” for “GXGXXG”) were completely conservative among 14 species. Association analyses showed that c.950+24C>A, c.950+45C>G, c.950+73G>A, c.950+83C>T and c.950+128delA of chicken ATGL gene (cATGL) were all significantly or highly significantly with cingulated fat width (CFW) (P < 0.05 or P < 0.01), and c.777−26C>A, c.950+45C>G, c.950+73G>A and c.950+118C>T were all significantly or highly significantly with pH value of breast muscle (BMPH) (P < 0.05).  相似文献   
198.
199.
A novel reductive compound with molecular weight of about 1000 Da, named Pc reducer, was purified from the liquid culture of a white-rot basidiomycete Phanerochaete chrysosporium. It was likely to have an alkene-ester structure according to Fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) spectra. Pc reducer reduced the hydroxyl radical HO and the stable nitroxide radical under certain conditions. It inhibited the repolymerization of the products from the oxidation of phenolic lignin-model compounds by reducing certain intermediate radicals. The activity of manganese peroxidases was promoted by Pc reducer at certain concentrations. Pc reducer could also weaken the repolymerization of fragments from the oxidation of Na-lignosulfonate by lignin peroxidases and manganese peroxidases. It has potential ability to improve the ligninolytic efficiency of peroxidases in P. chrysosporium.  相似文献   
200.
Shank length affects chicken leg health and longer shanks are a source of leg problems in heavy-bodied chickens. Identification of quantitative trait loci (QTL) affecting shank length traits may be of value to genetic improvement of these traits in chickens. A genome scan was conducted on 238 F2 chickens from a reciprocal cross between the Silky Fowl and the White Plymouth Rock breeds using 125 microsatellite markers to detect static and developmental QTL affecting weekly shank length and growth (from 1 to 12 weeks) in chickens. Static QTL affected shank length from birth to time t , while developmental QTL affected shank growth from time t− 1 to time t . Seven static QTL on six chromosomes (GGA2, GGA3, GGA4, GGA7, GGA9 and GGA23) were detected at ages of 2, 3, 4, 5, 6, 7, 9 and 12 weeks, and six developmental QTL on five chromosomes (GGA1, GGA2, GGA4, GGA5 and GGA23) were detected for five shank growth periods, weeks 2–3, 4–5, 5–6, 10–11 and 11–12. A static QTL and a developmental QTL ( SQSL1 and DQSL2 ) were identified at GGA2 (between ADL0190 and ADL0152 ). SQSL1 explained 2.87–5.30% of the phenotypic variation in shank length from 3 to 7 weeks. DQSL2 explained 2.70% of the phenotypic variance of shank growth between 2 and 3 weeks. Two static and two developmental QTL were involved chromosome 4 and chromosome 23. Two chromosomes (GGA7 and GGA9) had static QTL but no developmental QTL and another two chromosomes (GGA1 and GGA5) had developmental QTL but no static QTL. The results of this study show that shank length and shank growth at different developmental stages involve different QTL.  相似文献   
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