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QuEChERS-超高效液相色谱法同时测定硝基酚类物质方法的研究 被引量:3
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作者 刘玉 张同来 +2 位作者 杨利 刘芮 刘影 《含能材料》 EI CAS CSCD 北大核心 2015年第1期73-79,共7页
建立了超高效液相色谱法同时测定三硝基苯酚(苦味酸PA)、三硝基间苯二酚(斯蒂酚酸TNR)和三硝基均苯三酚(TNPG)等多硝基酚类含能材料在生产环境中土壤、地面沉积物中残留的14种硝基酚类物质的检测方法。样品经改进的QuE ChERS(快... 建立了超高效液相色谱法同时测定三硝基苯酚(苦味酸PA)、三硝基间苯二酚(斯蒂酚酸TNR)和三硝基均苯三酚(TNPG)等多硝基酚类含能材料在生产环境中土壤、地面沉积物中残留的14种硝基酚类物质的检测方法。样品经改进的QuE ChERS(快速、简单、价廉、高效、耐用、安全)前处理方法一步完成提取,经C18和石墨化炭黑(GCB)净化,采用Accucore PFP色谱柱(2.1 mm×150 mm i.d.,2.6μm)分离,用梯度洗脱,流动相为乙腈+0.02 mol·L-1乙酸铵盐缓冲溶液+0.1%甲酸,流速0.3 mL·min-1,注射量5μL。在波长220 nm处检测14种硝基酚类物质。结果表明,14种硝基酚类物质在0.2~50 mg·L-1浓度范围内呈良好线性关系,相关系数为0.9985~0.9995,相对标准偏差为3.6%~5.9%,平均回收率为81.3%~105.7%,检出限(LOD)为0.04~0.06 mg·kg-1。14种硝基酚类物质在22 min内完成分离。所建方法有良好的重复性和精度,可用于快速测定土壤中的酚类物质。 展开更多
关键词 分析化学 超高效液相色谱法 多硝基酚类 que CHE RS方法
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QuEChERS-GC/ECD法分析土壤和沉积物中残留有机氯农药和多氯联苯 被引量:12
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作者 蔡小虎 蔡述伟 +1 位作者 时磊 沈小明 《环境监控与预警》 2016年第3期14-17,共4页
建立了用快速、简单、廉价、有效、可靠及安全(QuEChERS)的方法净化、GC/ECD法测定沉积物中有机氯农药和多氯联苯的分析方法。目标化合物质量浓度在1.0~100μg/L范围内线性良好,相关系数均〉0.999,检出限为0.08~0.17μg/L。... 建立了用快速、简单、廉价、有效、可靠及安全(QuEChERS)的方法净化、GC/ECD法测定沉积物中有机氯农药和多氯联苯的分析方法。目标化合物质量浓度在1.0~100μg/L范围内线性良好,相关系数均〉0.999,检出限为0.08~0.17μg/L。以沉积物标准样品SRM1944为研究对象,用QuEChERS方法和传统方法进行提取比较,并用沉积物样品进行验证,回收率为87.8%~100.3%。方法快速、简单、可靠、安全。 展开更多
关键词 que ChERS 土壤 沉积物 有机氯农药 多氯联苯
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Validation of the General <i>Health Questionnaire</i>(GHQ-12) adapted to a work-related context 被引量:2
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作者 Francois-Xavier Lesage Sonia Martens-Resende +1 位作者 Frederic Deschamps Sophie Berjot 《Open Journal of Preventive Medicine》 2011年第2期44-48,共5页
Introduction: The aim of this study is to test the factorial structure and the internal consistency of the 12-items General Health Questionnaire adapted to work-related psychological distress (GHQW). Methods: A valida... Introduction: The aim of this study is to test the factorial structure and the internal consistency of the 12-items General Health Questionnaire adapted to work-related psychological distress (GHQW). Methods: A validated French version of the GHQ-12 was used and transformed to remind of the occupational context. A sample of 1014 workers completed the GHQW. Internal consis- tency was assessed by Cronbach’s α coefficient. The factorial structure was extracted with an exploratory factorial analysis (EFA). Results: The EFA run on the data yield to a one- factor structure explaining 60.5% of the total variance of the scale. The Cronbach’s alpha showed a very good internal consistency of the scale (α = 0.94). Conclusion: The findings support that the GHQW is a reliable and valid instrument for measuring work-related psychological distress in workers. This work-related version could find some applications in epide-miological research at work, in the study of psychosocial risk factors and in the occupational health physi- cian’s daily activity. 展开更多
关键词 OCCUPATIONAL HEALTH Mental HEALTH questionnaires Factor Analysis Statistical General HEALTH ques-tionnaire Validity
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基于QUE$TOR软件的地面工程投资估算 被引量:1
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作者 党学博 杨洁冰 《价值工程》 2017年第22期209-210,共2页
石油工程投资估算软件QUE$TOR具有工程方案描述准确、计算精度高、投资数据持续更新等特点。总结了QUE$TOR软件特点和操作流程,包括项目定义、油气田特征描述、确定开发方案、刻画工程方案、计算CAPEX和OPEX、完成投资规划等。通过与实... 石油工程投资估算软件QUE$TOR具有工程方案描述准确、计算精度高、投资数据持续更新等特点。总结了QUE$TOR软件特点和操作流程,包括项目定义、油气田特征描述、确定开发方案、刻画工程方案、计算CAPEX和OPEX、完成投资规划等。通过与实际投资进行对比,验证了软件的计算精度。QUE$TOR软件适用于项目概念设计、可行性研究以及资料较少的海外项目的投资估算。 展开更多
关键词 地面工程 投资估算 que$TOR软件 海外项目
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XI AWARDS CAMBODIAN QUEEN MOTHER FRIENDSHIP MEDAL
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《China Report ASEAN》 2020年第11期6-9,共4页
Chinese President Xi Jinping awarded Cambodian Queen Mother,Norodom Monineath Sihanouk,the Friendship Medal of the People’s Republic of China at a ceremony at the Great Hall of the People in Beijing on November 6.Que... Chinese President Xi Jinping awarded Cambodian Queen Mother,Norodom Monineath Sihanouk,the Friendship Medal of the People’s Republic of China at a ceremony at the Great Hall of the People in Beijing on November 6.Queen Mother Monineath is an important witness and promoter of China-Cambodia friendship,who has forged a tight bond with China since she accompanied Norodom Sihanouk,then Cambodian prince,to China in 1958 for the first time,Xi said when delivering a speech. 展开更多
关键词 que MOTHER queEN
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作为关系代词及连词的法语QUE与英语THAT的比较——基于认知语法的角度
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作者 陈晓霞 《江汉大学学报(社会科学版)》 2016年第2期119-123,129,共5页
从认知语法的角度对法语que与英语that的共同点、差异性与惯用法进行全面系统地比较:在句法功能上两者都可以作连词与关系代词;作连词时,需要注意que的一些特殊用法以及两者后面所跟从句语式的差别;作代词时,在关注两者共同点的同时要注... 从认知语法的角度对法语que与英语that的共同点、差异性与惯用法进行全面系统地比较:在句法功能上两者都可以作连词与关系代词;作连词时,需要注意que的一些特殊用法以及两者后面所跟从句语式的差别;作代词时,在关注两者共同点的同时要注意that的代替性与可省略性。法语学习者可利用法语和英语两种语言在句法上的象似性提高学习效率。 展开更多
关键词 que THAT 象似性 认知语法
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Empirical studies about quercetin increasing chemosensitivity on human lung adenocarcinoma cell line A549 被引量:1
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作者 Xuejun Zhan Runxiang Zhang +3 位作者 Yanping Xu Shuhua Yang Daze Xie Liwei Tan 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第7期380-383,共4页
Objective: The present study was designed to investigate whether quercetin exerts increasing chemosensitivity on human lung adenocarcinoma cells when quercetin combined with cisplatin (DDP) and vincristine (VCR) ... Objective: The present study was designed to investigate whether quercetin exerts increasing chemosensitivity on human lung adenocarcinoma cells when quercetin combined with cisplatin (DDP) and vincristine (VCR) in vitro respectively and its possible antitumor mechanism. To provide experimental proof for clinical combination application. Methods: Using intermittent administration of high dose VCR, human lung adenocarcinoma sensitive cell line (A549/S) was induced to VCR- resistant human lung adenocarcinoma cell line (A549NCR). MTT assay was adapted for examing the 50% inhibition (IC50) value of DDP and VCR on A549/S and A549/VCR when quercetin combined with DDP and VCR respectively. Results: IC50 of DDP on A549/S and A549/VCR was 10.18 and 12.35 mg/L, and the IC50 of VCR on the two cell lines was 1.21 and 12.77 rag/L, respectively. The resistance fold of A549/VCR on VCR and DDP was 10.55 and 121, respectively. When quercetin at concentration of 50, 100 and 200 pmol/L in combination with DDP and VCR respectively, the IC50 of DDP and VCR on A549/S and A549/VCR were obvious decreased (P 〈 0.05 - P 〈 0.01). Conclusion: The experiment results suggested that quercetin could increase the chemosensitivity and partly revise the resistance of A549NCR. 展开更多
关键词 quercetin que A549 lung adenocarcinoma cell line cisplatin (DDP) vincristine (VCR) increase chemosen-sitivity
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EFFECTS OF QUERCETIN ON MEMBRANE FLUIDITY OF INJURED VASCULAR ENDOTHELIAL CELLS WITH HYPOXIA AND THE LACK OF GLUCOSE
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作者 林蓉 刘俊田 甘伟杰 《Journal of Pharmaceutical Analysis》 SCIE CAS 2003年第2期196-198,201,共4页
Objective To study the effects of different concentrations of Quercetin on nitric oxide (NO) production and membrane fluidity of the injured human umbilical vein vascular endothelial cell line(ECV 304) with hypoxia... Objective To study the effects of different concentrations of Quercetin on nitric oxide (NO) production and membrane fluidity of the injured human umbilical vein vascular endothelial cell line(ECV 304) with hypoxia and the lack of glucose. Methods The experiments were performed in the culture of ECV 304 injured with hypoxia and the lack of glucose in vitro. The releases of intracellular lactate dehydrogenase(LDH) of ECV 304 was measured with automatic biochemistry analysis. NO level of ECV 304 was monitored with colorimetry. The membrane fluidity of ECV 304 was measured with the fluorescence polarization method. Results After ECV 304 was cultured in hypoxia and the the lack of glucose for 24 hours, the release of LDH and the membrane fluidity were increased significantly; NO level was decreased. Preincubation of ECV 304 with 20, 80,160 μ mol·L -1 of Quercetin for 24 hours reduced LDH activity, membrane fluidity and increased the level of NO in hypoxia and the lack of glucose induced ECV 304. Conclusion These results demonstrate that Quercetin can produce the protective effect on hypoxia and the lack of glucose induced injury of ECV 304 by increasing release of NO and changing membrane fluidity. 展开更多
关键词 quercetin(que) endothelial cells membrane fluidity hypoxia and the lack of glucose
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应用Omni pa Que脊髓造影的体会与评价
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作者 曲列夫 《中国医学影像技术》 CSCD 1990年第3期42-42,共1页
一、造影方法1.下行性造影患者俯卧位,双手握紧检查床的固定把手、下肢伸直、固定双侧踝关节、头低5°,前屈,电视监视下定位,缓慢的将造影剂注入椎管内。下行性造影检查,常用于颈椎病,颈椎外伤,上胸椎血管畸形、肿瘤、外伤等疾病。... 一、造影方法1.下行性造影患者俯卧位,双手握紧检查床的固定把手、下肢伸直、固定双侧踝关节、头低5°,前屈,电视监视下定位,缓慢的将造影剂注入椎管内。下行性造影检查,常用于颈椎病,颈椎外伤,上胸椎血管畸形、肿瘤、外伤等疾病。摄颈椎正位。 展开更多
关键词 脊髓造影 颈椎外伤 OMNI PA que 上胸椎 双斜位 造影方法 造影剂 电视监视 检查床 压缩性骨折
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新发现的月球陨石QUE93069
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《矿物岩石地球化学通报》 CAS CSCD 1994年第4期241-241,共1页
新发现的月球陨石QUE93069为了考察和研究太阳系形成演化及人类对宇宙空间的开发利用,美国和前苏联等先进国家不惜花费巨资实施Apollo登月和飞船探测计划,从月球取回昂贵的月岩标本。然而,截止1991年,从美国、日... 新发现的月球陨石QUE93069为了考察和研究太阳系形成演化及人类对宇宙空间的开发利用,美国和前苏联等先进国家不惜花费巨资实施Apollo登月和飞船探测计划,从月球取回昂贵的月岩标本。然而,截止1991年,从美国、日本和欧洲等南极科学考察队在南极地区... 展开更多
关键词 月球陨石 que93069 南极地区 南极科学考察 熔壳 斜长岩 开发利用 角砾岩 月壤 考察队
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ERATO,REINE D’ARMÉNIE,ÉTUDE HISTORIQUE ET NUMISMATIQUE
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作者 Roy Arakelian Maxime K.Yevadian 《Journal of Ancient Civilizations》 2021年第1期67-114,138,共49页
Introduction Les découvertes numismatiques récentes justifient un réexamen de la période mal connue des dernières années de la dynastie artaxiade en Grande-Arménie(fondée vers 1... Introduction Les découvertes numismatiques récentes justifient un réexamen de la période mal connue des dernières années de la dynastie artaxiade en Grande-Arménie(fondée vers 189 av.J.-C.par Artaxias Ier),et plus particulièrement la période concernant le ou les règnes d’Erato,reine d’Arménie. 展开更多
关键词 que DES LES
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CLINICAL OBSERVATION ON THE TREATMENT OF KNEE OSTEOARTHRITIS BY ACUPUNCTURE IN BA-HE TECHNIQUE
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作者 梁云武 谭源生 周君 《World Journal of Acupuncture-Moxibustion》 2005年第1期16-18,42,共4页
Objective: To observe the clinical therapeutic effect of Ba-He techniqu e of acupuncture in the treatment of knee osteoarthritis. Methods: A total of 90 cases of knee osteoarthritis were evenly randomized into Ba-He t... Objective: To observe the clinical therapeutic effect of Ba-He techniqu e of acupuncture in the treatment of knee osteoarthritis. Methods: A total of 90 cases of knee osteoarthritis were evenly randomized into Ba-He technique group (observation group) and common technique group (control group), with 45 cases in each group. Zusanli (足三里 ST 36), Heding (鹤顶 EX-LE 2) and Dubi (犊鼻 ST 35 ) were punctured respectively in Ba-He technique and common technique in the two gr oups. The therapeutic effects of the two groups were compared after one course o f treatment (10 sessions) in accordance with Japanese assessment criteria for kn ee-joint functions. Results: After treatment, among the 74 and 7 1 affected knees in the observation and control groups, the therapeutic effect was excellent in 42 (56.8%) and 26 (36.6%) knees, fine in 14 (18.9%) and 20 (28.2%), OK in 10 (13 .5%) and 11 (15.5%), and poor in 8 (10.8%) and 14 (19.7%) respectively. The ther apeutic effect of the observation group was significantly better than that of co ntrol group (P<0.01). Conclusion: The Ba- He technique of acupuncture applied to the above-mentioned three acupoints exerted remarkable therapeutic effect for k n ee osteoarthritis, which is obviously better than that of the common needling te chnique. 展开更多
关键词 Knee osteoarthritis Acupuncture Ba-He needling techni que
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全能先手DPS Que!007刻录机
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《新潮电子》 2003年第8期81-81,共1页
关键词 DIGITAL PERIPHERAL Solutions公司 que!007 刻录机 立体声输出 功能
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浅谈QUE$TOR软件的应用
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作者 石航 《价值工程》 2019年第33期193-195,共3页
随着我国海外油气业务的不断壮大和发展,工程投资估算对于新项目未来的盈利能力起着至关重要的影响。对于一些前端工程设计的项目评价工作,由于已知参数和条件比较少,如何客观准确的对项目进行评价,是项目评价人员应该深刻思考的问题。... 随着我国海外油气业务的不断壮大和发展,工程投资估算对于新项目未来的盈利能力起着至关重要的影响。对于一些前端工程设计的项目评价工作,由于已知参数和条件比较少,如何客观准确的对项目进行评价,是项目评价人员应该深刻思考的问题。美国IHS Markit公司开发的QUE$TOR软件,因其良好的精确度和可靠性得到了很多国际石油公司的认可。QUE$TOR在各个产油国和地区拥有自己的研发团队,其后台成本数据库每年更新两次,这种强大的专业信息搜集和整理的团队是很多国家不具备的,因此该软件将会在各国际石油公司中变得越来越重要。QUE$TOR软件适用于项目概念设计、可行性研究及资料较少的海外项目。本文目的是通过对石油工程投资估算软件QUE$TOR的流程研究,从中找出国际化石油公司对于项目投资和费用估算的关键节点,有助于我国石油公司与其竞争时了解竞争对手的最低报价,及调整投标策略。 展开更多
关键词 que$TOR 前端工程设计 石油工程投资估算 项目评价 海外项目
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Information in the Structure of Reality:the Scientific Worldview and the Fundamental Question of Philosophy
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作者 Konstantin Kolin 《学术界》 CSSCI 北大核心 2015年第1期257-260,共4页
We offer a new understanding of the scientific world and the contents of the basic question of philosophy,which is based on an analysis of the phenomenon of the specific information in the various components of the st... We offer a new understanding of the scientific world and the contents of the basic question of philosophy,which is based on an analysis of the phenomenon of the specific information in the various components of the structure of reality.It is shown that,in addition to material objects,processes,and events,in the real world are also intangible objects,processes and conditions that are in its information content.So the basic question of philosophy is proposed to treat the relationship as a tangible and intangible component of reality.More succinctly it can be formulated as the ratio of matter and information.This allows you to point to some new challenges studying the phenomenon of information in various components of the structure of reality. 展开更多
关键词 结构信息 科学世界观 哲学 组成部分 现实世界 信息内容 事件
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Single-cell profiling reveals a potent role of quercetin in promoting hair regeneration 被引量:4
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作者 Qian Zhao Yandong Zheng +11 位作者 Dongxin Zhao Liyun Zhao Lingling Geng Shuai Ma Yusheng Cai Chengyu Liu Yupeng Yan Juan Carlos Izpisua Belmonte Si Wang Weiqi Zhang Guang-Hui Liu Jing Qu 《Protein & Cell》 SCIE CSCD 2023年第6期398-415,共18页
Hair loss affects millions of people at some time in their life,and safe and efficient treatments for hair loss are a significant unmet medical need.We report that topical delivery of quercetin(Que)stimulates resting ... Hair loss affects millions of people at some time in their life,and safe and efficient treatments for hair loss are a significant unmet medical need.We report that topical delivery of quercetin(Que)stimulates resting hair follicles to grow with rapid follicular keratinocyte proliferation and replenishes perifollicular microvasculature in mice.We construct dynamic single-cell transcriptome landscape over the course of hair regrowth and find that Que treatment stimulates the differentiation trajectory in the hair follicles and induces an angiogenic signature in dermal endothelial cells by activating HIF-1αin endothelial cells.Skin administration of a HIF-1αagonist partially recapitulates the pro-angiogenesis and hair-growing effects of Que.Together,these findings provide a molecular understanding for the efficacy of Que in hair regrowth,which underscores the translational potential of targeting the hair follicle niche as a strategy for regenerative medicine,and suggest a route of pharmacological intervention that may promote hair regrowth. 展开更多
关键词 single-cell RNA-sequencing que hair follicle regeneration endothelial cells HIF-1α
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Que独立引导副词性从句
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作者 陈西凤 《法语学习》 1995年第1期46-47,58,共3页
Que独立引导副词性从句武汉交通科技大学陈西凤法语中que这个词的功能多变。它不仅是疑问代词、关系代词、还是连词、副词。它做连词时,主要用途一是引导名词性从句,在句中充当主语、宾语、表语、同位语、名词补语、形容词补语... Que独立引导副词性从句武汉交通科技大学陈西凤法语中que这个词的功能多变。它不仅是疑问代词、关系代词、还是连词、副词。它做连词时,主要用途一是引导名词性从句,在句中充当主语、宾语、表语、同位语、名词补语、形容词补语、副词补语成份。二是和其他的词构成... 展开更多
关键词 que 疑问代词 连词 副词性从句 法语
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Pour de meilleurs échanges interculturels——La magie d'Ang Lee telle que je la vois
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作者 刘迪 《法语学习》 2010年第3期12-14,共3页
Un célèbre virtuose des arts martiaux,une épée mystérieuse,des combats aériens alternants,l'humanité et la justice,ce sont des éléments culturels qui se déploient ... Un célèbre virtuose des arts martiaux,une épée mystérieuse,des combats aériens alternants,l'humanité et la justice,ce sont des éléments culturels qui se déploient dans Tigre et Dragon,film réalisé en 2000 par Ang Lee.En Occident,où le style 《 de cape et d'épée 》 chinois était moins connu, 展开更多
关键词 changes interculturels Pour de meilleurs La magie d’Ang Lee telle que je la vois
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Develop potential multi-target drugs by self-assembly of quercetin with amino acids and metal ion to achieve significant efficacy in anti-Alzheimer’s disease
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作者 Chunling Zhu Yuheng Yang +3 位作者 Xiaowen Li Xingyu Chen Xucong Lin Xiaoping Wu 《Nano Research》 SCIE EI CSCD 2022年第6期5173-5182,共10页
Exploring multi-target drugs(MTDs)is a prevalent method against Alzheimer’s disease(AD).However,the current developed MTDs based on the“framework combination”technique or using flavonoids have not realized better h... Exploring multi-target drugs(MTDs)is a prevalent method against Alzheimer’s disease(AD).However,the current developed MTDs based on the“framework combination”technique or using flavonoids have not realized better healing effects owing to a complex metabolic process and low bioavailability.Here,we propose an alternative strategy to develop self-assembled nanoparticles(NPs)as MTDs using 9-fluorenylmethyloxycarbonyl-tryptophan(Fmoc-Trp),quercetin(Que),and Fe^(2+)as building blocks through coordination and electrostatic interaction to generate Fmoc-Trp-Fe^(2+)-Que(FTFQ)NPs.Whether in cell or in vivo,FTFQ NPs exhibited considerable biocompatibility attributing to the inherent biological affinity of assembly units.By combining the advantages of assemble approach and nanostructures,the obtained FTFQ NPs greatly enhanced the bioavailability of Que and displayed synergistic therapeutic effects through reducing Aβaggregation in direct/indirect means and eliminating the toxicity induced by ROS and Aβoligomer/fibrils.Furthermore,FTFQ NPs could obviously restore the AD zebrafish’s mobility and stimulus response ability.More importantly,developing self-assembly NPs as MTDs could be an efficient and general method to promote other novel MTDs by extending the assemble units to other drugs,peptides,and metal ions.Based on above benefits,these self-assembled NPs could be as potential MTDs and show great promising application in AD treatment. 展开更多
关键词 Alzheimer’s disease multi-target drugs(MTDs) self-assembled nanoparticles(NPs) quercetin(que)
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SUCCESSIVELY ITERATIVE TECHNIQUE OF SIGN-CHANGING SOLUTION TO A NONLINEAR THIRD-ORDER BOUNDARY VALUE PROBLEM
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作者 Qingliu Yao (Dept. of Applied Math., Nanjing University of Finance and Economics, Nanjing 210003) 《Annals of Differential Equations》 2012年第2期242-246,共5页
The iterative technique of sign-changing solution is studied for a nonlinear third-order two-point boundary value problem, where the nonlinear term has the time sin-gularity. By applying the monotonically iterative te... The iterative technique of sign-changing solution is studied for a nonlinear third-order two-point boundary value problem, where the nonlinear term has the time sin-gularity. By applying the monotonically iterative technique, an existence theorem is established and two useful iterative schemes are obtained. 展开更多
关键词 nonlinear ordinary differential equation successively iterative techni-que sign-changing solution
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