全文获取类型
收费全文 | 376篇 |
免费 | 16篇 |
国内免费 | 1篇 |
出版年
2023年 | 3篇 |
2022年 | 5篇 |
2021年 | 10篇 |
2020年 | 14篇 |
2019年 | 9篇 |
2018年 | 10篇 |
2017年 | 6篇 |
2016年 | 11篇 |
2015年 | 16篇 |
2014年 | 13篇 |
2013年 | 30篇 |
2012年 | 24篇 |
2011年 | 32篇 |
2010年 | 21篇 |
2009年 | 25篇 |
2008年 | 29篇 |
2007年 | 28篇 |
2006年 | 20篇 |
2005年 | 14篇 |
2004年 | 19篇 |
2003年 | 14篇 |
2002年 | 14篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1990年 | 3篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1977年 | 2篇 |
1976年 | 3篇 |
排序方式: 共有393条查询结果,搜索用时 0 毫秒
361.
Radhika Khera Ahmad R Mehdipour Jani R Bolla Joerg Kahnt Sonja Welsch Ulrich Ermler Cornelia Muenke Carol V Robinson Gerhard Hummer Hao Xie Hartmut Michel 《The EMBO journal》2022,41(18)
Bacteria utilize small extracellular molecules to communicate in order to collectively coordinate their behaviors in response to the population density. Autoinducer‐2 (AI‐2), a universal molecule for both intra‐ and inter‐species communication, is involved in the regulation of biofilm formation, virulence, motility, chemotaxis, and antibiotic resistance. While many studies have been devoted to understanding the biosynthesis and sensing of AI‐2, very little information is available on its export. The protein TqsA from Escherichia coli, which belongs to the AI‐2 exporter superfamily, has been shown to export AI‐2. Here, we report the cryogenic electron microscopic structures of two AI‐2 exporters (TqsA and YdiK) from E. coli at 3.35 Å and 2.80 Å resolutions, respectively. Our structures suggest that the AI‐2 exporter exists as a homo‐pentameric complex. In silico molecular docking and native mass spectrometry experiments were employed to demonstrate the interaction between AI‐2 and TqsA, and the results highlight the functional importance of two helical hairpins in substrate binding. We propose that each monomer works as an independent functional unit utilizing an elevator‐type transport mechanism. 相似文献
362.
Amrutha H. Chidananda Radhika Khandelwal Aditya Jamkhindikar Asmita D. Pawar Anand K. Sharma Yogendra Sharma 《The Journal of biological chemistry》2022,298(9)
Secretagogin (SCGN) is a three-domain hexa-EF-hand Ca2+-binding protein that plays a regulatory role in the release of several hormones. SCGN is expressed largely in pancreatic β-cells, certain parts of the brain, and also in neuroendocrine tissues. The expression of SCGN is altered in several diseases, such as diabetes, cancers, and neurodegenerative disorders; however, the precise associations that closely link SCGN expression to such pathophysiologies are not known. In this work, we report that SCGN is an early responder to cellular stress, and SCGN expression is temporally upregulated by oxidative stress and heat shock. We show the overexpression of SCGN efficiently prevents cells from heat shock and oxidative damage. We further demonstrate that in the presence of Ca2+, SCGN efficiently prevents the aggregation of a broad range of model proteins in vitro. Small-angle X-ray scattering (BioSAXS) studies further reveal that Ca2+ induces the conversion of a closed compact apo-SCGN conformation into an open extended holo-SCGN conformation via multistate intermediates, consistent with the augmentation of chaperone activity of SCGN. Furthermore, isothermal titration calorimetry establishes that Ca2+ enables SCGN to bind α-synuclein and insulin, two target proteins of SCGN. Altogether, our data not only demonstrate that SCGN is a Ca2+-dependent generic molecular chaperone involved in protein homeostasis with broad substrate specificity but also elucidate the origin of its altered expression in several cancers. We describe a plausible mechanism of how perturbations in Ca2+ homeostasis and/or deregulated SCGN expression would hasten the process of protein misfolding, which is a feature of many aggregation-based proteinopathies. 相似文献
363.
Nair Radhika V. Dileep Kottilil Gummaluri Venkata Siva Vijayan C. 《Plasmonics (Norwell, Mass.)》2017,12(5):1649-1656
Plasmonics - We present a systematic computational study on the optical properties of a new composite structure based on ZnS–metal core-shell particles, which can find applications in light... 相似文献
364.
365.
366.
367.
368.
369.
370.
Shashi K. Khurana Velagalety Krishnamoorthy Virinder S. Parmar Radhika Sanduja Harmohinder L. Chawla 《Phytochemistry》1982,21(8):2145-2146
A trimethylcoumarin has been isolated, for the first time from the stem of Trigonelia foenum-graecum along with some known compounds. Based upon spectral and analytical data and comparison with a synthetic sample, it has been assigned the structure 3, 4, 7-trimethylcoumarin. 相似文献