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超声成象

国外医学（生物医学工程分册） 1989年第6期12卷 347-351页

作者： wells p N T 丁仲奇

导论在过去的十年里,超声成象在科学与技术上都取得了巨大的进展。本文着重评述医学超声诊断发展的前沿,确认某些将来看起来更有前景的领域,并考虑某些在物理学和技术上同时出现的一些问题。我们并不企图涉及新的和正在出现的临床应用,... 详细信息

导论在过去的十年里,超声成象在科学与技术上都取得了巨大的进展。本文着重评述医学超声诊断发展的前沿,确认某些将来看起来更有前景的领域,并考虑某些在物理学和技术上同时出现的一些问题。我们并不企图涉及新的和正在出现的临床应用,然而值得注意的是新技术会导新的超声诊断,也就是说最终会决定临床的应用。

关键词：超声成像诊断

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导弹自动驾驶仪的最优-古典综合设计法

系统工程与电子技术 1982年第5期 41-49页

作者： F.W.Nesline ,B.H.wells ,p.Zarchan ,陈敏

把最优控制方法直接用于全频带自动驾驶仪的设计,会导致所构成的控制系统需要附加仪表,并敏感于高频模型的变动。本文介绍了一种设计方法,它用古典控制理论来限定高频设计,用现代控制理论来获得最优的低频性能。文中介绍了对一个独立的... 详细信息

把最优控制方法直接用于全频带自动驾驶仪的设计,会导致所构成的控制系统需要附加仪表,并敏感于高频模型的变动。本文介绍了一种设计方法,它用古典控制理论来限定高频设计,用现代控制理论来获得最优的低频性能。文中介绍了对一个独立的滚动姿态自动驾驶仪所取得的结果,以说明古典控制理论与现代控制理论结合使用所取得的好处。

关键词：自动驾驶仪舵机陀螺余度现代控制理论自动领航仪甲板机械控制论综合设计法穿越频率交越频率古典控制理论

A 2.45GHz High Current Ion Source for Neutron production

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Chinese physics C 2007年第S1期31卷 232-235页

作者： J.W.Kwan R.Gough R.Keller B.A.Ludewigt M.Regis R.p.wells J.H.Vainionpaa Lawrence Berkeley National Laboratory 1 Cyclotron RoadBerkeleyCA 94720USA

A 2.45GHz microwave-driven ion source is being used to provide 40mA of deuterium ion beam (peak current) for an RFQ accelerator as part of a neutron source *** have also designed a 60kV electrostatic LEBT using computer *** our experiment,we measured the hydrogen and deuterium ion beam currents as functions of discharge power,gas flow,and magnetic field *** required beam current was obtained using leas than 700W of net microwave power with a gas flow of less than *** the rise time data,it was determined that in order to obtain a high percentage of atomic ions in the beam, the beam extraction should start after 1ms of switching on the microwave *** steady state,the proton fraction was above 90%.

关键词： microwave-driven ECR ion source proton deuterium beam

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将保护区管理与地方需求和愿望相结合

AMBIO－人类环境杂志 2004年第B12期33卷 490-495页

作者： Michael p. wells Thomas O. McShane 梁君（译）周立志（校）非洲和亚洲关于环境保护和经济发展的资深顾问国际WWF的高级保护顾问不详

自然保护主义者认为由于没有当地人的合作和支持,许多保护区未来的发展前景已经受到限制,特别是发展中国家。自从20世纪80年代以来,保护和发展相结合计划(ICDp)试图使公园管理与地方的需要和愿望相一致,但结果通常令人失望。然而,在不... 详细信息

自然保护主义者认为由于没有当地人的合作和支持,许多保护区未来的发展前景已经受到限制,特别是发展中国家。自从20世纪80年代以来,保护和发展相结合计划(ICDp)试图使公园管理与地方的需要和愿望相一致,但结果通常令人失望。然而,在不违背保护目标的前提下,取得地方的合作和支持仍然是公园管理的首要任务。幸运的是,来自ICDp的经验教训为下一轮生物多样性保护计划,包括那些有关脱贫计划,以及在生态系统和景观尺度上实施的计划,提供了一次重要的借鉴机会。较新和有希望的措施已经开始将适应性管理、新的利益相关者参与模式和将站点层次的工作与政策制订和制度出台等内容结合进来。

关键词：保护区管理愿望 20世纪80年代求和公园管理发展中国家生物多样性适应性管理利益相关者

静脉血栓栓塞症的抗血栓治疗：美国《胸科学》杂志指南

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中国全科医学 2016年第9期19卷 989-990页

作者： Kearon C Akl EA Ornelas J Blaivas A Jimenez D Bounameaux H Huisman M King CS MorrisT Sood N Stevens SM Vintch JRE wells p Woller SC Moores CL 本刊编辑部机构不详

包括深静脉血栓和肺栓塞在内的静脉血栓栓塞症是癌症患者的主要并发症,发生率为4%~20%,并且是常见的潜在致命性急症。本文介绍了美国《胸科学》杂志指南中VET的抗血栓治疗的部分内容,其以第9版《美国胸内科医师学会循证临床实践指南》... 详细信息

包括深静脉血栓和肺栓塞在内的静脉血栓栓塞症是癌症患者的主要并发症,发生率为4%~20%,并且是常见的潜在致命性急症。本文介绍了美国《胸科学》杂志指南中VET的抗血栓治疗的部分内容,其以第9版《美国胸内科医师学会循证临床实践指南》中的《静脉血栓栓塞症的抗血栓治疗：抗血栓治疗和阻止血栓形成》一文为参照,基于静脉血栓栓塞症治疗的Ⅲ期试验的发表年份,对口服抗凝剂（达比加群、利伐沙班、阿哌沙班、依度沙班）进行先后阐述（但是这一排序并不是指南专家组对药剂的优劣排序）,以为临床医生提供参考。

关键词：静脉血栓栓塞纤维蛋白溶解药抗凝药指南

Acute colonic pseudo-obstruction: A systematic review of aetiology and mechanisms

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World Journal of Gastroenterology 2017年第30期23卷 5634-5644页

作者： Cameron I wells Gregory O’Grady Ian p Bissett Department of Surgery University of Auckland Department of Surgery Auckland District Health Board

To critically review the literature addressing the definition, epidemiology, aetiology and pathophysiology of acute colonic pseudo-obstruction (ACpO). METHODSA systematic search was performed to identify articles investigating the aetiology and pathophysiology of ACpO. A narrative synthesis of the evidence was undertaken. RESULTSNo consistent approach to the definition or reporting of ACpO has been developed, which has led to overlapping investigation with other conditions. A vast array of risk factors has been identified, supporting a multifactorial aetiology. The pathophysiological mechanisms remain unclear, but are likely related to altered autonomic regulation of colonic motility, in the setting of other predisposing factors. CONCLUSIONFuture research should aim to establish a clear and consistent definition of ACpO, and elucidate the pathophysiological mechanisms leading to altered colonic function. An improved understanding of the aetiology of ACpO may facilitate the development of targeted strategies for its prevention and treatment.

关键词： Acute colonic pseudoobstruction Acute colonic pseudo-obstruction Colonic Intestinal pseudo obstruction Ogilvie’s syndrome pseudo-Obstruction pseudo-Obstruction

Gold modified cobalt-based Fischer-Tropsch catalysts for conversion of synthesis gas to liquid fuels

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Frontiers of Chemical Science and Engineering 2013年第3期7卷 262-269页

作者： Alan J. Mccue Jura Aponaviciute Richard p.K. wells James A. Anderson Surface Chemistry and Catalysis Group Department of Chemistry University of Aberdeen AB24 3UE Abcrdccn UK Surface Chemistry and Catalysis Group School of Engineering University of Aberdeen AB24 3UE Aberdeen UK

The addition of Au as a promoter/modifier for alumina supported Co catalyst has been studied by combined in-situ high temperature, high pressure Fourier transform infrared （FTIR） and on-line gas chromatography. The combination of these tools permitted the state of the active catalyst surface to be monitored while following the elution of reaction products during the first 5-7 h on stream of the catalyst. The catalysts under study were a 10%Co/ A1203 and a 2.5%Au/10%Co/A1203. Samples were characterised before use using Raman and temperature programmed reduction （TpR）. During the initial stages of reaction, hydrocarbons were built up on the surface of the catalyst as monitored by FTIR and the nature and amount of these species were assessed in terms of CH2/CH3 ratio and the density of these alkyl fragments by employing absorption coefficients for the individual components. The nature and reducibility of the Co particles were modified by the presence of Au while the later also shifted the CO/ H2 balance by acting as an effective water-gas shift catalyst during the early stages of reaction. This characteristic was lost during reaction as a consequence of redistribution of the two metallic phases.

关键词： gold modified catalyst conversion of synthesis gas

Interfacial Strategies for Smart Slippery Surfaces

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Journal of Bionic Engineering 2020年第4期17卷 633-643页

作者： Glen McHale Rodrigo Ledesma-Aguilar Gary George wells Smart Materials&Surfaces Laboratory Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle upon TyneNE18STUK

The problem of contact line pinning on surfaces is pervasive and contributes to problems from ring stains to ice *** we provide a single conceptual framework for interfacial strategies encompassing five strategies for modifying the solid-liquid interface to remove pinning and increase droplet *** biomimetic strategies are included,(i)reducing the liquid-solid interfacial area inspired by the Lotus effect,(ii)converting the liquid-solid contact to a solid-solid contact by the formation of a liquid marble inspired by how galling aphids remove honeydew,and(iii)converting the liquid-solid interface to a liquid-lubricant contact by the use of a lubricant impregnated surface inspired by the Nepenthes pitcher *** further strategies are,(iv)converting the liquid-solid contact to a liquid-vapor contact by using the Leidenfrost effect,and(v)converting the contact to a liquid-liquid-like contact using slippery omniphobic covalent attachment of a liquid-like coating(SOCAL).Using these approaches,we explain how surfaces can be designed to have smart functionality whilst retaining the mobility of contact lines and ***,we show how droplets can evaporate at constant contact angle,be positioned using a Cheerios effect,transported by boundary reconfiguration in an energy invariant manner,and drive the rotation of solid components in a Leidenfrost heat *** conceptual framework enables the rationale design of surfaces which are slippery to liquids and is relevant to a diverse range of applications.

关键词： superhydrophobicity SLIpS liquid marbles leidenfrost SOCAL

Keap1 eye on the target:chemoprevention of liver cancer

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Acta pharmacologica Sinica 2007年第9期28卷 1331-1342页

作者： Melinda Sue YATES Thomas wells KENSLER Department of pharmacology and Molecular Sciences Johns Hopkins School of Medicine Department of pharmacology and Molecular Sciences Johns Hopkins School of Medicine and Department of Environmental Health SciencesJohns Hopkins Bloomberg School of Public HealthBaltimoreMaryland 21205USA

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide,causing nearly 600 000 deaths each *** risk of HCC due to chronicinfection with hepatitis B virus (HBV) and exposure to dietary aflatoxins is respon-sible for many of these *** strategies targeting HBV infection andaflatoxin exposure could dramatically impact the rates of *** HBVvaccination programs have begun in some high-risk *** to reduceaflatoxin contamination in food stores have also been ***,complete elimination of aflatoxin contamination might not be *** thisreason,chemoprevention strategies which alter aflatoxin disposition are a practi-cal strategy to reduce the incidence of HCC in populations with high dietaryaflatoxin *** mechanisms of aflatoxin-induced hepatocarcinogenesisare well *** knowledge provides the basis for evaluation of both expo-sures to aflatoxin,as well as modulation of aflatoxin disposition by *** of aflatoxin DNA damage and toxicity as well as other metabo-lites can be used as biomarkers to evaluate modulation of aflatoxin *** of aflatoxin disposition can be achieved through induction of conju-gating and cytoprotective *** of these enzymes are regulated throughKelch ECH-associating protein 1 (Keap1)-NF-E2-related factor 2(Nrf2)-antioxi-dant response element (ARE) signaling,making this pathway an important mo-lecular target for *** studies have identified several classesof chemopreventive agents which induce cytoprotective *** inducersinclude phenolic antioxidants,dithiolethiones,isothiocyanates,and ***,clinical interventions have shown that inducers of Keap 1-Nrf2-ARE signaling increase cytoprotective enzyme expression,resulting in modula-tion of aflatoxin *** work remains to be done in order to takepromising chemopreventive agents from preclinical evaluation to

关键词： chemoprevention Kelch ECH associating protein 1 Nrf2 sulforaphane oltipraz triterpenoids dithiolethiones hepatocellular carcinoma