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101.
Hui Tang Na Shen Huijuan Jin Dan Liu Xiaoping Miao Ling-Qiang Zhu 《Molecular neurobiology》2013,48(3):404-411
Glycogen synthase kinase 3 (GSK-3) is a well-known conserved and ubiquitous protein kinase and playing a pivotal role in neurodevelopment, neurogenesis, learning/memory, and neuronal cell death. Dysfunction of GSK-3 had been seen in multiple neurodegenerative and psychiatric diseases. Bipolar disorder and schizophrenia are two common psychiatric diseases first occur in adolescence or young adulthood. They share similar risk genes as well as clinical symptoms, which make it is difficult to be discriminated from each other. Here, by using meta-analysis we reported that glycogen synthase kinase 3β promoter inactive mutant rs334558 may contribute to the development of schizophrenia not bipolar disorder. This might be used to distinguish these two diseases. 相似文献
102.
Nan Liang Lili Jia Yang Liu Bing Liang Dejuan Kong Mengmeng Yan Shumei Ma Xiaodong Liu 《Cellular signalling》2013,25(12):2530-2539
BackgroundATM plays an important role in response to DNA damage, while the roles of ATM in radiation-induced autophagy are still unclear in cervical cancer cells.MethodsHuman cervical cancer cells, Hela, were used, and cell models with ATM?/? and MAPK14?/? were established by gene engineering. Western blot was implemented to detect protein expression. MDC staining and GFP-LC3 relocalization were used to detect autophagy. CCK-8 was used to detect cell viability. Radiosensitivity was analyzed by colony formation assays. Co-immunoprecipitation was used to detect the interaction between different proteins, and apoptosis was detected by flow cytometry.ResultsAfter radiation autophagy was induced, illustrated by the increase of MAPLC3-II/MAPLC3-I ratio and decrease of p62, and phosphorylation of ATM simultaneously increased. ATM?/? cells displayed hypersensitivity but had no influence on IR-induced apoptosis. Then inhibitor of ATM, KU55933, ATM and MAPK14 silencing were used, and autophagy was induced by IR more than 200% in control, and only by 35.72%, 53.18% and 24.76% in KU55933-treated cells, ATM?/? and MAPK14?/? cells, respectively. KU55933 inhibited IR-induced autophagy by activating mTOR pathways. ATM silencing decreased the expression of MAPK14 and mTOR signals significantly. Beclin's bond to PI3KIII and their interaction increased after IR, while in ATM?/? and MAPK14?/? cells this interaction decreased after IR. Both ATM and MAPK14 interacted with Beclin, while ATM?/? and MAPK14?/? cells showed no interaction.ConclusionsATM could promote IR-induced autophagy via the MAPK14 pathway, the mTOR pathway, and Beclin/PI3KIII complexes, which contributed to the effect of ATM on radiosensitivity. 相似文献
103.
104.
The microbial reduction process of goethite by Shewanella decolorationis S12 was evaluated. The results showed the electron shuttle, anthraquinone-2-sulfonate (AQS), could enhance the microbial reduction. The thermodynamic and kinetic characteristics of goethite reduction by microorganisms were influenced by AQS, concentrations of iron oxide, and electron donor. Transformation between oxidized and reduced species of the electron shuttle during the microbial reduction could be newly noticed. Two interactive steps, biotic and abiotic, were involved in the microbial reduction of Fe (III) oxide mediated by electron shuttle. 相似文献
105.
Xiaofei Liu Nan Zuo Huanan Guan Chunran Han Shi Wen Xu 《Biological trace element research》2013,154(2):202-209
Exposure to Manganese (Mn) is a common phenomenon due to its environmental pervasiveness. To investigate the Mn-induced toxicity on cerebral trace element levels and crucial nitric oxide parameters on brain of birds, 50-day-old male Hyline cocks were fed either a commercial diet or a Mn-supplemented diet containing 600, 900, 1,800 mg kg?1. After being treated with Mn for 30, 60, and 90 days, the following were determined: the changes in contents of copper (Cu), iron (Fe), zinc (Zn), calcium (Ca), selenium (Se) in brain; inducible nitric oxide synthase-nitric oxide (iNOS-NO) system activity in brain; and histopathology and ultrastructure changes of cerebral cortex. The results showed that Mn was accumulated in brain and the content of Cu and Fe increased. However, the levels of Zn and Se decreased and the Ca content presented no obvious regularity. Exposure to Mn significantly elevated the content of NO and the expression of iNOS mRNA. Activity of total NO synthase (T NOS) and iNOS appeared with an increased tendency. These findings suggested that Mn exposure resulted in the imbalance of cerebral trace elements and influenced iNOS in the molecular level, which are possible underlying nervous system injury mechanisms induced by Mn exposure. 相似文献
106.
Ruodan Nan Stuart Tetchner Elizabeth Rodriguez Po-Jung Pao Jayesh Gor Imre Lengyel Stephen J. Perkins 《The Journal of biological chemistry》2013,288(26):19197-19210
The sub-retinal pigment epithelial deposits that are a hallmark of age-related macular
degeneration contain both C3b and millimolar levels of zinc. C3 is the central protein of
complement, whereas C3u is formed by the spontaneous hydrolysis of the thioester bridge in C3.
During activation, C3 is cleaved to form active C3b, then C3b is inactivated by Factor I and Factor
H to form the C3c and C3d fragments. The interaction of zinc with C3 was quantified using analytical
ultracentrifugation and x-ray scattering. C3, C3u, and C3b associated strongly in >100
μm zinc, whereas C3c and C3d showed weak association. With zinc, C3 forms soluble
oligomers, whereas C3u and C3b precipitate. We conclude that the C3, C3u, and C3b association with
zinc depended on the relative positions of C3d and C3c in each protein. Computational predictions
showed that putative weak zinc binding sites with different capacities exist in all five proteins,
in agreement with experiments. Factor H forms large oligomers in >10 μm zinc. In
contrast to C3b or Factor H alone, the solubility of the central C3b-Factor H complex was much
reduced at 60 μm zinc and even more so at >100 μm zinc. The
removal of the C3b-Factor H complex by zinc explains the reduced C3u/C3b inactivation rates by zinc.
Zinc-induced precipitation may contribute to the initial development of sub-retinal pigment
epithelial deposits in the retina as well as reducing the progression to advanced age-related
macular degeneration in higher risk patients. 相似文献
107.
Jingjing Ben Yan Zhang Rongmei Zhou Haiyang Zhang Xudong Zhu Xiaoyu Li Hanwen Zhang Nan Li Xiaodan Zhou Hui Bai Qing Yang Donghai Li Yong Xu Qi Chen 《The Journal of biological chemistry》2013,288(27):20076-20084
Atherosclerosis is considered a disease of chronic inflammation largely initiated and perpetuated by macrophage-dependent synthesis and release of pro-inflammatory mediators. Class A scavenger receptor (SR-A) expressed on macrophages plays a key role in this process. However, how SR-A-mediated pro-inflammatory response is modulated in macrophages remains ill defined. Here through immunoprecipitation coupled with mass spectrometry, we reported major vault protein (MVP) as a novel binding partner for SR-A. The interaction between SR-A and MVP was confirmed by immunofluorescence staining and chemical cross-linking assay. Treatment of macrophages with fucoidan, a SR-A ligand, led to a marked increase in TNF-α production, which was attenuated by MVP depletion. Further analysis revealed that SR-A stimulated TNF-α synthesis in macrophages via the caveolin- instead of clathrin-mediated endocytic pathway linked to p38 and JNK, but not ERK, signaling pathways. Importantly, fucoidan invoked an enrichment of MVP in lipid raft, a caveolin-reliant membrane structure, and enhanced the interaction among SR-A, caveolin, and MVP. Finally, we demonstrated that MVP elimination ameliorated SR-A-mediated apoptosis in macrophages. As such, MVP may fine-tune SR-A activity in macrophages which contributes to the development of atherosclerosis. 相似文献
108.
Tarsha Ward Ming Wang Xing Liu Zhikai Wang Peng Xia Youjun Chu Xiwei Wang Lifang Liu Kai Jiang Huijuan Yu Maomao Yan Jianyu Wang Donald L. Hill Yuejia Huang Tongge Zhu Xuebiao Yao 《The Journal of biological chemistry》2013,288(22):15771-15785
The microtubule cytoskeleton network orchestrates cellular dynamics and chromosome stability in mitosis. Although tubulin acetylation is essential for cellular plasticity, it has remained elusive how kinetochore microtubule plus-end dynamics are regulated by p300/CBP-associated factor (PCAF) acetylation in mitosis. Here, we demonstrate that the plus-end tracking protein, TIP150, regulates dynamic kinetochore-microtubule attachments by promoting the stability of spindle microtubule plus-ends. Suppression of TIP150 by siRNA results in metaphase alignment delays and perturbations in chromosome biorientation. TIP150 is a tetramer that binds an end-binding protein (EB1) dimer through the C-terminal domains, and overexpression of the C-terminal TIP150 or disruption of the TIP150-EB1 interface by a membrane-permeable peptide perturbs chromosome segregation. Acetylation of EB1-PCAF regulates the TIP150 interaction, and persistent acetylation perturbs EB1-TIP150 interaction and accurate metaphase alignment, resulting in spindle checkpoint activation. Suppression of the mitotic checkpoint serine/threonine protein kinase, BubR1, overrides mitotic arrest induced by impaired EB1-TIP150 interaction, but cells exhibit whole chromosome aneuploidy. Thus, the results identify a mechanism by which the TIP150-EB1 interaction governs kinetochore microtubule plus-end plasticity and establish that the temporal control of the TIP150-EB1 interaction by PCAF acetylation ensures chromosome stability in mitosis. 相似文献
109.
In situ hydrogen utilization for high fraction acetate production in mixed culture hollow-fiber membrane biofilm reactor 总被引:1,自引:0,他引:1
Fang Zhang Jing Ding Nan Shen Yan Zhang Zhaowei Ding Kun Dai Raymond J. Zeng 《Applied microbiology and biotechnology》2013,97(23):10233-10240
Syngas fermentation is a promising route for resource recovery. Acetate is an important industrial chemical product and also an attractive precursor for liquid biofuels production. This study demonstrated high fraction acetate production from syngas (H2 and CO2) in a hollow-fiber membrane biofilm reactor, in which the hydrogen utilizing efficiency reached 100 % during the operational period. The maximum concentration of acetate in batch mode was 12.5 g/L, while the acetate concentration in continuous mode with a hydraulic retention time of 9 days was 3.6?±?0.1 g/L. Since butyrate concentration was rather low and below 0.1 g/L, the acetate fraction was higher than 99 % in both batch and continuous modes. Microbial community analysis showed that the biofilm was dominated by Clostridium spp., such as Clostridium ljungdahlii and Clostridium drakei, the percentage of which was 70.5 %. This study demonstrates a potential technology for the in situ utilization of syngas and valuable chemical production. 相似文献
110.
Jiachuan Pan Xin Xie Wang Tian Ali Adem Bahar Nan Lin Fangchao Song Jing An Dacheng Ren 《Applied microbiology and biotechnology》2013,97(20):9145-9154
Persisters are a small subpopulation of bacterial cells that are dormant and extremely tolerant to antibiotics. The intrinsic antibiotic tolerance of persisters also facilitates the development of multidrug resistance through acquired mechanisms based on drug resistance genes. In this study, we demonstrate that (Z)-4-bromo-5-(bromomethylene)-3-methylfuran-2(5H)-one (BF8) can reduce persistence during Escherichia coli growth and revert the antibiotic tolerance of its persister cells. The effects of BF8 were more profound when the pH was increased from 6 to 8.5. Although BF8 is a quorum sensing (QS) inhibitor, similar effects were observed for the wild-type E. coli RP437 and its ΔluxS mutant, suggesting that these effects did not occur solely through inhibition of AI-2-mediated QS. In addition to its effects on planktonic persisters, BF8 was also found to disperse RP437 biofilms and to render associated cells more sensitive to ofloxacin. At the doses that are effective against E. coli persister cells, BF8 appeared to be safe to the tested normal mammalian cells in vitro and exhibited no long-term cytotoxicity to normal mouse tissues in vivo. These findings broadened the activities of brominated furanones and shed new light on persister control. 相似文献