检索结果-南通市图书馆

Selective Acid Hydrolysis Condition for the Composition and Linkage with a Fructofuranosyl Backbone of a Polysaccharide from Angelica sinensis (Oliv) Diels

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第10期17卷 1369-1372页

作者： gui yun xu Yang CHEN Ru Xian CHEN Institute of Chemistry Chinese Academy of Sciences Beijing 100080 Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences Beijing 100050

A new polysaccharide was extracted and purified from the roots of Angelica sinensis （Oliv） Diels （ASD）. Its composition and linkage was elucidated by selective hydrolysis and GC/MS analysis of its derivatives. The polysaccharide was made of → 1） Fruf（2→and→6） Glcp （l→as its backbone with highly branched structure. To our best knowledge, this is the first report of the fructose residue in polysaccharides from the roots of the ASD.

关键词： Selective hydrolysis fructofuranosyl backbone GC/MS

Isolation, purification and structural characterization of a water-soluble polysaccharide HM41 from Halenia elliptica ***

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2016年第6期27卷 979-983页

作者： Chun-Lan Liu Yang Li gui-yun xu Ya-Shuang Li College of Life and Environmental Science Minzu University of ChinaBeijing 100081China Beijing Engineering Research Center of Food Environment and Public Health Minzu University of ChinaBeijing 100081China Institute of Chemistry Chinese Academy of SciencesBeijing 100080China

A water-soluble polysaccharide, HM（41）, was obtained from Halenia elliptica D. Don by acidic ethanol fractionation and gel filtration. Its homogeneity was confirmed by chromatography using multiple systems. HM（41） was composed of rhamnose（Rha）, arabinose（Ara）, xylose（Xyl）, mannose（Man）,galactose（Gal）, glucose（Glc） with a molar ratio of 1.0：5.5：1.8：3.0：9.4：21. The average molecular weight of HM（41） was approximately 1.17 ＊ 10~4. Periodate oxidation, Smith degradation, methylation and GC, IR,NMR, XRD, GC–MS analysis were used for the structural analysis of HM（41）. Its main chain was composed mainly of β-（1→4）Gal, β-（1→4）Glc and β-（1→6）Glc. β-（1 →4）Gal were substituted at 6-O and on average there were 14 branches among 23 main chain residues;（1→ 4）Glc had no branch;（1→6）Glc were substituted at 3-O and on average there were 9 branches among 14 main chain residues. The side chain was composed of（1→3,6）-Rha,（1→4）/（1→5）-Ara,（1 →4）/（1→5）-Xyl,（1→4,6）-Man and（1→2）-Glc. The terminal residue was composed of Ara, Xyl, Man, Gal, and Glc. Then, we demonstrated that HM and HM（41） had strong scavenging activities in vitro hydroxyl. Overall, HM and HM（41） may have potential applications in the antioxidants for medical and food industry.

关键词： Halenia elliptica D.Don Polysaccharide Isolation purification Structural analysis Antioxidant activities

Switchable dual-wavelength erbium-doped fiber laser with a tilted fiber grating

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2007年第1期3卷 27-29页

作者： JIN Long KAI gui-yun xu Ling-ling LIU Bo ZHANG Jian LIU Yan-ge YUAN Shu-zhong DONG Xiao-yi Institute of Modern Optics Nankai University Tianjin 300071 China

A dual-wavelength erbium doped fiber laser with a tilted fiber Bragg grating and photonic crystal fiber is proposed and demonstrated. In the laser, a 2W EDFA provides gain for all the laser lines; the highly nonlinear photonic crystal fiber introduces dynamic energy transfer between the two wavelengths caused by four wave mixing effect, so that a stable dual- wavelength oscillation at room temperature is implemented. Different switching modes can be achieved by adjusting the lateral offset between the fiber grating and the guiding single mode fiber or by varying the state of polarization in the laser cavity. The maximum of output power of the laser has reached 314mW.

关键词：开关双波长铒掺杂光纤激光器倾斜光纤光栅光子晶体光纤

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi xu Junqiu Jia Rui Mao Xiang Cao yun xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review,we provide a comprehensive overview of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury

Inverse Learning Control of Nonlinear Systems Using Support Vector Machines

在线全文

学校读者我要写书评

暂无评论

Journal of Shanghai Jiaotong university(Science) 2005年第2期10卷 135-138,142页

作者：胡中辉李远贵蔡云泽许晓鸣 Dept. of Automation Shanghai Jiaotong Univ. Shanghai 200030 China

An inverse learning control scheme using the support vector machine (SVM) for regression was proposed. The inverse learning approach is originally researched in the neural networks. Compared with neural networks, SVMs overcome the problems of local minimum and curse of dimensionality. Additionally, the good generalization performance of SVMs increases the robustness of control system. The method of designing SVM inverse learning controller was presented. The proposed method is demonstrated on tracking problems and the performance is satisfactory.

关键词： support vector machines learning control inverse model nonlinear system

miR-148a通过下调HPIP的表达抑制人非小细胞肺癌A549细胞的增殖

在线全文

学校读者我要写书评

暂无评论

中国血液流变学杂志 2017年第3期27卷 251-255页

作者：徐桂丽徐云华倪才方苏州大学附属第一医院介入科江苏苏州215006

目的探讨外周血miR-148a在非小细胞肺癌（NSCLC）中的作用及机制.方法收集32例NSCLC患者及12名健康对照者的血清样本,运用ELISA检测miR-148a和HPIP的表达.通过双荧光素酶报告基因检测及Western Blot技术探讨miR-148a对HPIP的作用机制... 详细信息

目的探讨外周血miR-148a在非小细胞肺癌（NSCLC）中的作用及机制.方法收集32例NSCLC患者及12名健康对照者的血清样本,运用ELISA检测miR-148a和HPIP的表达.通过双荧光素酶报告基因检测及Western Blot技术探讨miR-148a对HPIP的作用机制.利用CCK-8法分别检测过表达miR-148a和敲除HPIP对A549细胞增殖的影响.结果 NSCLC血清中miR-148a低表达而HPIP高表达.并且miR-148a可以直接靶向HPIP的3＇-UTR区域而抑制HPIP水平.另外,过表达miR-148a和敲除HPIP都可以抑制A549细胞的增殖.结论 miR-148a通过靶向HPIP3＇-UTR来抑制A549细胞的增殖.

关键词： miR-148a HPIP NSCLC 增殖

Regulation and function of endoplasmic reticulum autophagy in neurodegenerative diseases

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第1期20卷 6-20页

作者： Xiu-yun Zhao De-En xu Ming-Lei Wu Ji-Chuan Liu Zi-Ling Shi Quan-Hong Ma Department of Neurology and Clinical Research Center of Neurological Disease the Second Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Neuroscience&Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases Soochow UniversitySuzhouJiangsu ProvinceChina Department of Neurology Jiangnan University Medical CenterWuxiJiangsu ProvinceChina

The endoplasmic reticulum,a key cellular organelle,regulates a wide variety of cellular *** reticulum autophagy,one of the quality control systems of the endoplasmic reticulum,plays a pivotal role in maintaining endoplasmic reticulum homeostasis by controlling endoplasmic reticulum turnover,remodeling,and *** this review,we briefly describe the endoplasmic reticulum quality control system,and subsequently focus on the role of endoplasmic reticulum autophagy,emphasizing the spatial and temporal mechanisms underlying the regulation of endoplasmic reticulum autophagy according to cellular *** also summarize the evidence relating to how defective or abnormal endoplasmic reticulum autophagy contributes to the pathogenesis of neurodegenerative *** summary,this review highlights the mechanisms associated with the regulation of endoplasmic reticulum autophagy and how they influence the pathophysiology of degenerative nerve *** review would help researchers to understand the roles and regulatory mechanisms of endoplasmic reticulum-phagy in neurodegenerative disorders.

关键词： autophagy endoplasmic reticulum endoplasmic reticulum autophagy endoplasmic reticulum quality control system endoplasmic reticulum receptors endoplasmic reticulum-associated degradation neurodegeneration neurodegenerative disease selective autophagy unfolded protein response

1,2,4-三嗪类化合物的研究 Ⅵ.3-取代-5-羟基-6-甲基-1,2,4-三嗪的合成

在线全文

学校读者我要写书评

暂无评论

化学学报 1980年第6期 581-583页

作者：李钧李云贵王序北京医学院药学系

本文报道用高锰酸钾在碱性溶液中氧化3-甲硫基-5-羟基-6-甲基-1,2,4-三嗪(3)以合成3-甲砜基-5-羟基-6-甲基-1,2,4-三嗪(13),后者在缓和条件下经亲核性取代反应制得一系列3-取代-5-羟基-6-甲基-1,2,4-三嗪类化合物(1)。为研究1,2,4-三嗪... 详细信息

本文报道用高锰酸钾在碱性溶液中氧化3-甲硫基-5-羟基-6-甲基-1,2,4-三嗪(3)以合成3-甲砜基-5-羟基-6-甲基-1,2,4-三嗪(13),后者在缓和条件下经亲核性取代反应制得一系列3-取代-5-羟基-6-甲基-1,2,4-三嗪类化合物(1)。为研究1,2,4-三嗪类化合物生理活性,拟合成(1)类化合物。3-巯基-5-羟基-6-甲基-1,2,4-三嗪(2),3-甲硫基-5-羟基6-甲基-1,2,4-三嗪(3),3-乙硫基-5-羟基-6-甲基-1,2,4-三嗪(4)及3-苄硫基-5-羟基-6-甲基-1,2,4-三嗪(5)均已合成。

关键词：甲硫基高锰酸钾烷硫基过锰酸钾高锰酸盐甲基链烷基取代反应交换反应完成反应亲核性熔点熔解温度酚钠酚盐

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

信号肽疏水性的提高促进青霉素G酰化酶分泌

生物化学与生物物理学报 2000年第2期32卷 163-168页

作者：杨运桂徐京宁胡泰山钱友存杨胜利龚毅中国科学院上海生命科学研究院上海生物工程研究中心!上海200233 华东理工大学国家生物反应器工程重点实验室!上海200237 中国科学院上海生命科学?

设计和合成了一段具有连续 10个亮氨酸强疏水核心的信号肽 (artificialsignalpeptide ,ASP) ,由EcoRI KpnI位点融合到青霉素G酰化酶 ( penicillinGacylase ,PAC)信号肽 (wildtypesignalpeptide,WTSP)的 - 4Pro位点 ,分别构建了PAC表达质粒 :pKKpacΔSP ,pKKpacWTSP ,pKKpacASP ,pETpacWTSP ,pETpacASP。ASP与WTSP均为 2 6个氨基酸 ,两者N端为MK ,C端均为PAVA。通过酶活性的测定及Western印迹分析 ,分别在tac,T7及氧调控表达系统中研究ASP和WTSP对PAC分泌的影响。结果表明 ,与WTSP相比 ,ASP对PAC酶活水平平均提高了约 63 % ,对PAC前体的分泌能力平均提高了约 4 1% ,通过提高信号肽疏水核心疏水性有效促进了青霉素G酰化酶的分泌。

关键词：青霉素G酰化酶信号肽疏水核心疏水性