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排序方式: 共有8577条查询结果,搜索用时 15 毫秒
51.
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Sayer JA Otto EA O'Toole JF Nurnberg G Kennedy MA Becker C Hennies HC Helou J Attanasio M Fausett BV Utsch B Khanna H Liu Y Drummond I Kawakami I Kusakabe T Tsuda M Ma L Lee H Larson RG Allen SJ Wilkinson CJ Nigg EA Shou C Lillo C Williams DS Hoppe B Kemper MJ Neuhaus T Parisi MA Glass IA Petry M Kispert A Gloy J Ganner A Walz G Zhu X Goldman D Nurnberg P Swaroop A Leroux MR Hildebrandt F 《Nature genetics》2006,38(6):674-681
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提出了一种求解变分不等式与不动点问题的惯性次梯度外梯度算法,证明了其弱收敛性定理,通过数值实验验证所得的理论结果. 相似文献
54.
Xiaofeng Ma He Li Yating He Junwei Hao 《Cellular and molecular life sciences : CMLS》2017,74(20):3667-3686
O-linked β-N-acetylglucosaminylation (O-GlcNAcylation) is involved in the regulation of many cellular cascades and neurological diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and stroke. In the brain, the expression of O-GlcNAcylation is notably heightened, as is that of O-linked N-acetylglucosaminyltransferase (OGT) and β-N-acetylglucosaminidase (OGA), the presence of which is prominent in many regions of neurological importance. Most importantly, O-GlcNAcylation is believed to contribute to the normal functioning of neurons; conversely, its dysregulation participates in the pathogenesis of neurological disorders. In neurodegenerative diseases, O-GlcNAcylation of the brain’s key proteins, such as tau and amyloid-β, interacts with their phosphorylation, thereby triggering the formation of neurofibrillary tangles and amyloid plaques. An increase of O-GlcNAcylation by pharmacological intervention prevents neuronal loss. Additionally, O-GlcNAcylation is stress sensitive, and its elevation is cytoprotective. Increased O-GlcNAcylation ameliorated brain damage in victims of both trauma-hemorrhage and stroke. In this review, we summarize the current understanding of O-GlcNAcylation’s physiological and pathological roles in the nervous system and provide a foundation for development of a therapeutic strategy for neurological disorders. 相似文献
55.
Zhiqiang Ma Zhenlong Xin Wencheng Di Xiaolong Yan Xiaofei Li Russel J. Reiter Yang Yang 《Cellular and molecular life sciences : CMLS》2017,74(21):3989-3998
Ischemia/reperfusion (IR) injury occurs in many organs and tissues, and contributes to morbidity and mortality worldwide. Melatonin, an endogenously produced indolamine, provides a strong defense against IR injury. Mitochondrion, an organelle for ATP production and a decider for cell fate, has been validated to be a crucial target for melatonin to exert its protection against IR injury. In this review, we first clarify the mechanisms underlying mitochondrial dysfunction during IR and melatonin’s protection of mitochondria under this condition. Thereafter, special focus is placed on the protective actions of melatonin against IR injury in brain, heart, liver, and others. Finally, we explore several potential future directions of research in this area. Collectively, the information compiled here will serve as a comprehensive reference for the actions of melatonin in IR injury identified to date and will hopefully aid in the design of future research and increase the potential of melatonin as a therapeutic agent. 相似文献
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Zhang Z Lee JC Lin L Olivas V Au V LaFramboise T Abdel-Rahman M Wang X Levine AD Rho JK Choi YJ Choi CM Kim SW Jang SJ Park YS Kim WS Lee DH Lee JS Miller VA Arcila M Ladanyi M Moonsamy P Sawyers C Boggon TJ Ma PC Costa C Taron M Rosell R Halmos B Bivona TG 《Nature genetics》2012,44(8):852-860
Human non-small cell lung cancers (NSCLCs) with activating mutations in EGFR frequently respond to treatment with EGFR-targeted tyrosine kinase inhibitors (TKIs), such as erlotinib, but responses are not durable, as tumors acquire resistance. Secondary mutations in EGFR (such as T790M) or upregulation of the MET kinase are found in over 50% of resistant tumors. Here, we report increased activation of AXL and evidence for epithelial-to-mesenchymal transition (EMT) in multiple in vitro and in vivo EGFR-mutant lung cancer models with acquired resistance to erlotinib in the absence of the EGFR p.Thr790Met alteration or MET activation. Genetic or pharmacological inhibition of AXL restored sensitivity to erlotinib in these tumor models. Increased expression of AXL and, in some cases, of its ligand GAS6 was found in EGFR-mutant lung cancers obtained from individuals with acquired resistance to TKIs. These data identify AXL as a promising therapeutic target whose inhibition could prevent or overcome acquired resistance to EGFR TKIs in individuals with EGFR-mutant lung cancer. 相似文献
57.
广西壮族自治区青蒿生态气候适宜性区划 总被引:1,自引:0,他引:1
为有效指导广西青蒿(Artemisia annua L.)种植,本文结合文献,分析影响广西青蒿素(artemisinin)含量的主要气象要素,并建立了青蒿素含量-气象要素数学模型.利用地理信息系统的空间分析功能,选取与广西青蒿素含量相关性最高的17个气象要素,作为区划指标,对广西进行青蒿生态气候适宜性区划,划分出四级适宜区.可知广西西部和东北部的山区是最适宜青蒿生长的区域,青蒿苗期和花期时的气象要素对青蒿素含量的影响最大,花期时处于光照强度较高、温度相对较低、降水量较小区域内的青蒿中青蒿素含量较高.本文为广西青蒿种植适宜区域的选择提供了理论依据,对类似研究也具有参考意义. 相似文献
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59.
法语的推广在法国对外文化推广中的作用是非常重要的.文章将对法国对外文化政策的起源、社会背景、法语的重要地位以及结合中国实际进行了综合分析研究. 相似文献
60.
中小企业自主创新障碍及对策 总被引:1,自引:0,他引:1
创新是一个国家和一个地区经济发展的不竭动力,文章从中小企业在自主创新过程中的障碍入手,为中小企业如何提高自主创新能力提供建议。 相似文献