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31.
Jie Sun Tao Tao Wei Zhao Lisha Wei Fan She Pei Wang Yeqiong Li Yanyan Zheng Xin Chen Wei Wang Yanning Qiao Xue-Na Zhang Min-Sheng Zhu 《遗传学报》2019,46(3):109-118
Several factors have been implicated in obesity-related hypertension, but the genesis of the hypertension is largely unknown. In this study, we found a significantly upregulated expression of CPI-17(C-kinasepotentiated protein phosphatase 1 inhibitor of 17 kDa) and protein kinase C(PKC) isoforms in the vascular smooth muscles of high-fat diet(HFD)-fed obese mice. The obese wild-type mice showed a significant elevation of blood pressure and enhanced calcium-sensitized contraction of vascular smooth muscles. However, the obese CPI-17-deficient mice showed a normotensive blood pressure, and the calcium-sensitized contraction was consistently reduced. In addition, the mutant muscle displayed an abolished responsive force to a PKC activator and a 30%-50% reduction in both the initial peak force and sustained force in response to various G protein-coupled receptor(GPCR) agonists. Our observations showed that CPI-17-mediated calcium sensitization is mediated through a GPCR/PKC/CPI-17/MLCP/RLC signaling pathway. We therefore propose that the upregulation of CPI-17-mediated calcium-sensitized vasocontraction by obesity contributes to the development of obesity-related hypertension. 相似文献
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Background
There is growing interest in the attachment of proteins to solid supports for the development of supported catalysts, affinity matrices, and micro devices as well as for the development of planar and bead based protein arrays for multiplexed assays of protein concentration, interactions, and activity. A critical requirement for these applications is the generation of a stable linkage between the solid support and the immobilized, but still functional, protein.Methodology
Solid supports including crosslinked polymer beads, beaded agarose, and planar glass surfaces, were modified to present an oligoglycine motif to solution. A range of proteins were ligated to the various surfaces using the Sortase A enzyme of S. aureus. Reactions were carried out in aqueous buffer conditions at room temperature for times between one and twelve hours.Conclusions
The Sortase A transpeptidase of S. aureus provides a general, robust, and gentle approach to the selective covalent immobilization of proteins on three very different solid supports. The proteins remain functional and accessible to solution. Sortase mediated ligation is therefore a straightforward methodology for the preparation of solid supported enzymes and bead based assays, as well as the modification of planar surfaces for microanalytical devices and protein arrays. 相似文献36.
Jing-Yu Liu Chao-Wen She Zhong-Li Hu Fen Li Ying Diao Li-Hua Liu Yun-Chun Song 《植物学报(英文版)》2007,49(11):1634-1639
Using genomic in situ hybridization with genomic DNA, high-order chromatin fibers were successfully exhibited under a light microscope through the cell cycle in barley, rice, maize and field bean. From the interphase to prophase and metaphase of mitosis, the fibers were basically similar. Each was estimated to be around 200 nm in diameter, but the strength of signals was not the same along the fiber length. Through the cell cycle a series of dynamic distribution changes occurred in the fibers. In the interphase, they were unraveled. At the early prophase they were arranged with parallel and mirror symmetry. During late-prophase and metaphase, the fibers were bundled and became different visible chromosomes. The parallel coiling and mirror symmetry structures were visible clearly until the metaphase. In anaphase they disappeared. During telophase, in peripheral regions of congregated chromosome group, borderlines of the chromosomes disappeared and the fibers were unraveled. This demonstrated that mitotic chromosomes are assembled and organized by parallel and adjacent coiling of the fibers and the fibers should be the highest order structure for DNA coiling. 相似文献
37.
三峡库区水体中固氮微生物多样性及其影响因素 总被引:1,自引:1,他引:0
【目的】研究分析不同时空条件下三峡库区水体固氮微生物多样性,并探讨其与地球化学参数的相关性。【方法】采集三峡库区不同时间(三月份和六月份)和空间(干流与支流)的水体样品,对其进行地球化学参数分析,并通过构建克隆文库分析样品中固氮功能基因(nifH)的多样性进而探讨其与水体地化参数的相关关系。【结果】统计分析显示三峡库区水体固氮微生物α-多样性和群落组成具有时空差异。支流水体样品的固氮微生物α-多样性高于干流水体样品;六月水体样品的固氮微生物α-多样性高于三月水体样品。三峡库区三月水体样品中的固氮微生物群落以Proteobacteria (50.3%)和Firmicutes (40.0%)为主;六月水体样品的固氮微生物群落以Proteobacteria(48.4%)、Firmicutes(25.4%)和Cyanobacteria(19.0%)为主。Mantel检验结果显示:固氮微生物群落结构的差异与温度、pH和DIC等地球化学参数具有显著(P0.05)相关性,其中温度和pH的相关性系数最大。【结论】三峡库区固氮微生物的种群结构和多样性具有时空差异,影响三峡水库水体中固氮微生物群落结构与多样性的主要环境因素为温度和pH,同时浊度、DIC、氨氮也对库区水体固氮微生物群落结构和多样性有一定的影响。 相似文献
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Kai‐Wei Yu Ning Zhong Yu Xiao Zhen‐Yu She 《Biology of the cell / under the auspices of the European Cell Biology Organization》2019,111(6):143-160
Chromosome congression is essential for faithful chromosome segregation and genomic stability in cell division. Centromere‐associated protein E (CENP‐E), a plus‐end‐directed kinesin motor, is required for congression of pole‐proximal chromosomes in metaphase. CENP‐E accumulates at the outer plate of kinetochores and mediates the kinetochore‐microtubule capture. CENP‐E also transports the chromosomes along spindle microtubules towards the equatorial plate. CENP‐E interacts with Bub1‐related kinase, Aurora B and core kinetochore components during kinetochore–microtubule attachment. In this review, we introduce the structures and mechanochemistry of kinesin‐7 CENP‐E. We highlight the complicated interactions between CENP‐E and partner proteins during chromosome congression. We summarise the detailed roles and mechanisms of CENP‐E in mitosis and meiosis, including the kinetochore–microtubule capture, chromosome congression/alignment in metaphase and the regulation of spindle assembly checkpoint. We also shed a light on the roles of CENP‐E in tumourigenesis and CENP‐E's specific inhibitors. 相似文献
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To further our knowledge of intracellular copper transport, we used a proteomics strategy to search for hepatic proteins with copper-binding ability. Hep G2 cytosolic and microsomal fractions were applied to a copper(II)-loaded immobilized metal-affinity chromatography (IMAC) column. Protein identification was performed with 2-D gel electrophoresis and mass spectrometry. We identified 48 cytosolic proteins and 19 microsomal proteins displaying copper-binding ability. These proteins are diverse in function. Fifty-two of the 67 proteins contain putative metal-binding domains. We have identified many components of the Hep G2 copper metalloproteome including a large number of proteins not previously known to bind copper. 相似文献