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51.
Xia W  Fu W  Cai L  Kong H  Cai X  Liu J  Wang Y  Zou M  Xu D 《Gene》2012,504(2):233-237
Angiogenin (Ang) is known to induce cell proliferation and inhibit apoptosis by cellular signaling pathways and by direct nuclear functions of Ang, but the mechanism of action for Ang is not yet clear. The aim of present study was to identify novel binding partner of Ang and to explore the underlying mechanism. With the use of yeast two-hybrid screening system, Ang was used as the bait to screen human fetal hepatic cDNA library for interacting proteins. Four and a half LIM domains 3 (FHL3) was identified as a novel Ang binding partner. The interaction between Ang and the full length FHL3 was further confirmed by yeast two-hybrid assay, co-immunoprecipitation and GST pull-down assays. Furthermore, FHL3 was required for Ang-mediated HeLa cell proliferation and nuclear translocation of Ang. These findings suggest that the interaction between Ang and FHL3 may provide some clues to the mechanisms of Ang-regulated cell growth and apoptosis.  相似文献   
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Peptidome analysis has received increasing attention in recent years. Cancer diagnosis by serum peptidome has also been reported by peptides' profiling for discovery of peptide biomarkers. Tissue, which may have a higher biomarker concentration than blood, has not been investigated extensively by means of peptidome analysis. Here, a method for the peptidome analysis of mouse liver was developed by the combination of size exclusion chromatography (SEC) prefractionation with nano-liquid chromatography-tamdem mass spectrometry (nanoLC-MS/MS) analysis. The extracted peptides from mouse liver were separated according to their molecular weight using a size exclusion column. MALDI-TOF MS was used to characterize the molecular weight distribution of the peptides in fractions eluted from the SEC column. The low molecular weight (LMW) (MW < 3000 Da) peptides in the collected fractions were directly analyzed by LC-MS/MS which resulted in the identification of 1181 unique peptides (from 371 proteins). The high molecular weight (HMW) (MW > 3000 Da) peptides in the early two fractions from the SEC column were first digested with trypsin, and the resulted digests were then analyzed by LC-MS/MS, which led to the identification of 123 and 127 progenitor proteins of the HMW peptides in fractions 1 and 2, respectively. Analysis of the peptides' cleavage sites showed that the peptides are cleaved in regulation, which may reflect the protease activity and distribution in body, and also represent the biological state of the tissue and provide a fresh source for biomarker discovery.  相似文献   
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邹伟  寇慧  韩畅 《微生物学报》2021,61(12):3829-3835
【目的】白酒可培养微生物的分离筛选是白酒行业重要的研究内容,本文旨在构建中国白酒生产环境中可培养微生物信息数据库。【方法】数据库信息主要来源于通过人工查阅和整理目前已发表的白酒微生物的相关的文献报道和菌种保藏中心相关的筛选自白酒生态系统的微生物信息。数据库主要设计3个功能:(1)白酒可培养微生物信息检索:通过菌株名称、分离位置、培养基、代谢产物等为条件检索相关的白酒可培养微生物信息,从而获取该白酒微生物详细的生理生化与分类学信息;(2)培养基信息检索:通过特定培养基成分,培养基编号和名称检索相关的培养基信息,包括培养的组成和配制方法。(3)数据更新:在线上传新的可培养微生物和培养基信息。【结果】目前数据库共收1221种白酒可培养微生物和295种培养基信息,网址为:http://cmbaijiu.i-sanger.com/。【结论】本数据库是我国白酒领域首个可培养微生物信息的数据库,将有助于白酒微生物培养的相关研究工作开展。  相似文献   
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The pathogenesis of age-related hearing loss (ARHL) remains unclear. OPA1 is the sole fusion protein currently known to be situated in the inner mitochondrial membrane, which is pivotal for maintaining normal mitochondrial function. While it has already been demonstrated that mutations in OPA1 may lead to hereditary deafness, its involvement in the occurrence and development of ARHL has not been previously explored. In our study, we constructed D-gal-induced senescent HEI-OC1 cells and the cochlea of C57BL/6J mice with a mutated SUMOylation site of SIRT3 using CRISPR/Cas9 technology. We found enhanced L-OPA1 processing mediated by activated OMA1, and increased OPA1 acetylation resulting from reductions in SIRT3 levels in senescent HEI-OC1 cells. Consequently, the fusion function of OPA1 was inhibited, leading to mitochondrial fission and pyroptosis in hair cells, ultimately exacerbating the aging process of hair cells. Our results suggest that the dysregulation of mitochondrial dynamics in cochlear hair cells in aged mice can be ameliorated by activating the SIRT3/OPA1 signaling. This has the potential to alleviate the senescence of cochlear hair cells and reduce hearing loss in mice. Our study highlights the significant roles played by the quantities of long and short chains and the acetylation activity of OPA1 in the occurrence and development of ARHL. This finding offers new perspectives and potential targets for the prevention and treatment of ARHL.  相似文献   
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为了研究在15—25lux和230—280lux两种光照条件下雌雄龟纹瓢虫成虫搜索行为转换的因子及作地域集中型搜索持续的时间(giving-up-time——简写为GUT)长短,按Nakamuta(1982)方法给予以下五种刺激:a.和棉蚜接触;b.捕获棉蚜或仅食去撕去量;c.完全吃下捕获的1头棉蚜;d.和琼脂块(2×2×2mm)接触;e.吃下沾有棉蚜体液的琼脂块(2×2×2mm)。以不给予刺激作对照,观察每种刺激对搜索行为转换的激发作用。结果表明五种刺激的任一种刺激都可激发搜索行为的转换。结果还表明GUT值随刺激程度大小而变化,其大小顺序为a=d相似文献   
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Injured renal tubular epithelial cells (RTECs) have been recently thought to directly contribute to the accumulation of myofibroblasts in renal tubulointerstitial fibrosis through a process of epithelial to mesenchymal transition (EMT). However, the factors inducing RTECs to undergo EMT and the underlying mechanisms need to be further elucidated. This study aimed to determine the EMT-inducing activity of proinflammatory cytokine TNF-α and the role for complement 3 (C3) in this activity in an in vitro model of human RTECs (HK-2 cells). Wild type HK-2 cells were treated with TNF-α, IFN-γ or C3a; C3 siRNA- or control siRNA-carrying HK-2 cells were treated with TNF-α. Changes in the cell morphology and phenotype were assessed by microscopy, RT-PCR, western blotting, and immunostaining. TNF-α effectively induced HK-2 cells to express C3 and to transform into morphologically myofibroblast-like cells that lost E-cadherin (a classical epithelial cell marker) expression but acquired alpha-smooth muscle actin (α-SMA, a classical myofibroblast differentiation marker) expression. C3 siRNA robustly attenuated all the morphologic and phenotypic changes induced by TNF-α but the control siRNA showed no effect. Our preliminary observations suggest that TNF-α may induce EMT in RTECs through inducing C3 expression.  相似文献   
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