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World j.urnal of Stem Cells 2012年第9期4卷 94-100页

作者： Alex j.Lomas George GQ Chen Alicia j.El Haj.nicholas R Forsyth Guy Hilton Research Centre Keele University Stoke on Trent ST4 7QB United Kingdom Department Biological Sciences and Biotechnology School of Life Science Tsinghua University

AIM: To establish the potential of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) as a material for tendon repair. METHODS: The biocompatibility of PHBHHx with both rat tenocytes (rT) and human mesenchymal stem cells (hMSC) was explored by monitoring adhesive characteristics on films of varying weight/volume ratios coupled to a culture atmosphere of either 21% O2 (air) or 2% O2 (physiological normoxia). The diameter and stiffness of PHBHHx films was established using optical coherence tomography and mechanical testing, respectively. RESULTS: Film thickness correlated directly with weight/volume PHBHHx (r2 = 0.9473) ranging from 0.1 mm (0.8% weight/volume) to 0.19 mm (2.4% weight/volume). Film stiffness on the other hand displayed a biphasic response which increased rapidly at values > 1.6% weight/volume. Optimal cell attachment of rT required films of ≥ 1.6% and ≥ 2.0% weight/volume PHBHHx in 2% O2 and 21% O2 respectively. A qualitative adhesion increase was noted for hMSC in films ≥ 1.2% weight/volume, becoming significant at 2% weight/volume in 2% O2. An increase in cell adhesion was also noted with ≥ 2% weight/volume PHBHHx in 21% O2. Cell migration into films was not observed. CONCLUSION: This evaluation demonstrates that PHBHHx is a suitable polymer for future cell/polymer replacement strategies in tendon repair.

关键词： Mesenchymal stem cell Tenocytes Polyhydroxyalkanoates Hypoxia Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)

Percutaneous coronary intervention of totally occluded coronary venous bypass grafts:An exercise in futility?

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World j.urnal of Cardiology 2021年第9期13卷 493-502页

作者： Evan W Nardone Brandon M Madsen Melissa M McCarey David L Fischman nicholas j.Ruggiero Paul Walinsky Alec Vishnevsky Michael P Savage Department of Medicine Thomas Jefferson UniversityPhiladelphiaPA 19107United States Department of Anesthesiology Medstar Georgetown University HospitalWashingtonDC 20007United States j.fferson Clinical Research Institue Thomas Jefferson UniversityPhiladelphiaPA 19107United States

BACKGROUND Percutaneous coronary intervention(PCI)of diseased saphenous vein grafts(SVG)continues to pose a clinical *** PCI guidelines give a class III recommendation against performing PCI on chronically occluded ***,contemporary outcomes after SVG intervention have incrementally improved with distal protection devices,intracoronary vasodilators,drug-eluting stents,and prolonged dual antiplatelet *** To reassess the procedural and long-term outcomes of PCI for totally occluded SVG with contemporary *** This was a retrospective observational study conducted at a single university *** study population consisted of 35 consecutive patients undergoing PCI of totally occluded ***-procedure dual antiplatelet therapy was continued for a minimum of one year and aspirin was continued *** outcomes were assessed at a mean follow-up of 1221±1038 *** primary outcome was freedom from a maj.r adverse cardiac event(MACE)defined as the occurrence of any of the following:death,myocardial infarction,stroke,repeat bypass surgery,repeat PCI,or graft *** The study group included 29 men and 6 women with a mean age of 69±12 *** was present in 14(40%)*** patients had Canadian Heart Classification class III or IV *** presentation was an acute coronary syndrome in 34(97%)*** SVG age was 12±5 *** duration of occlusion was acute(24 h to 30 d)in 26%,and late(>30 d)in 40%.PCI was initially successful in 29/35 SVG occlusions(83%).Total stent length was 52±35 *** complications of distal embolization or no-reflow occurred in 6(17%)*** longer term follow-up,MACE-free survival was only 30%at 3 years and 17%at 5 *** PCI of totally occluded SVG can be performed with a high procedural success ***,its clinical utility remains limited by poor follow-up outcomes.

关键词： Coronary artery bypass grafting Coronary stents Chronic total occlusion Percutaneous coronary intervention Restenosis Saphenous vein grafts

比较多种改进院内手卫生干预措施的效果：系统性综述和网络荟萃分析

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英国医学杂志中文版 2016年第1期19卷 8-9页

作者： Nantasit Luangasanatip Maliwan Hongsuwan Direk Limmathurotsakul Yoel Lubell Andie S Lee Stephan Harbarth nicholas P j.Day nicholas Graves BenS Cooper 肖颖不详首都医科大学附属北京朝阳医院

目的评估世界卫生组织（WH0）2005年提出的方法（WHO-5）和其他干预措施对于提升院内医务人员手卫生的相对效果，同时总结资源利用情况。设计系统性综述和网络荟萃（meta）分析。数据来源联机医学文献分析和检索系统（Medline）、荷兰... 详细信息

目的评估世界卫生组织（WH0）2005年提出的方法（WHO-5）和其他干预措施对于提升院内医务人员手卫生的相对效果，同时总结资源利用情况。设计系统性综述和网络荟萃（meta）分析。数据来源联机医学文献分析和检索系统（Medline）、荷兰医学文摘数据库（Embase）、护理学数据库（CINAHL）、英国国家健康体系经济评价数据库、英国国家健康体系评论和传播中心、考克兰图书馆、EPOC存储器f2009年12月-2014年2月）；以相同检索词获取的系统性综述（1980-2009）中筛选出的研究。

关键词：疗效比较网络系统医院

Diversity of Insect Flower Visitors on Macadamia within a Monoculture Orchard in Murang’a County, Central Kenya

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Advances in Entomology 2023年第4期11卷 239-255页

作者： nicholas I. Nj.e j.mes W. Muthomi George N. Chemining’wa j.hn H. Nderitu j.siah Achieng j.mes j. Odanga Department of Plant Science and Crop Protection University of Nairobi Nairobi Kenya Invertebrate Zoology Section National Museums of Kenya Nairobi Kenya

Macadamia is cultivated for its nutritious edible kernel. In Kenya, the crop is predominantly grown by smallholder farmers mainly for export markets. Macadamia trees also enhance agro-forestry conservation, in the East African farmlands, by providing habitat and floral resources to beneficial arthropods such as insect pollinators. Allogamy of macadamia flowers is largely dependent on insects that pollinate and consequently influence the nut set, retention and yield. However, there is limited information on macadamia insect flower visitors in Kenya. This article assessed the diversity of insects that forage flowers of macadamia crop, and further evaluated their temporal distribution, in Murang’a county, central Kenya. Insect flower visitors were sampled weekly using a butterfly net for twelve consecutive months, from j.nuary 2021 to December 2021. Sixty-one insect species were recorded foraging macadamia flowers in Murang’a county, central Kenya. There was a statistical difference in the Simpson diversity index among weather seasons, dry, long rain, cold and short rain (p Apis mellifera), a key pollinator species, being the most abundant flower visitor. This study provides strong baseline information, to scientists and farmers, on probable macadamia pollinator species, in central Kenya. .

关键词： Macadamia Flowers Insect Diversity Kenya

Using quality improvement methods to increase use of pain prevention strategies for childhood vaccination

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World j.urnal of Clinical Pediatrics 2017年第1期6卷 81-88页

作者： j.nnifer Verrill Schurman Amanda D Deacy Rebecca j.j.hnson j.lynn Parker Kristi Williams Dustin Wallace Mark connelly Lynn Anson Kevin Mroczka Division of Developmental and Behavioral Sciences Children's Mercy Primary Care Clinic Children’s Mercy Division of General Academic Pediatrics Children’s Mercy Comprehensive Pain Management Children’s Mercy Department of Pediatrics Children’s Mercy

AIM To increase evidence-based pain prevention strategy use during routine vaccinations in a pediatric primary care clinic using quality improvement *** Specific intervention strategies(i.e.,comfort positioning,nonnutritive sucking and sucrose analgesia,distraction) were identified,selected and introduced in three waves,using a Plan-Do-Study-Act ***-wide change was measured from baseline to post-intervention by:(1) percent of vaccination visits during which an evidence-based pain prevention strategy was reported as being used; and(2) caregiver satisfaction ratings following the ***,self-reported staff and caregiver attitudes and beliefs about pain prevention were measured at baseline and 1-year post-intervention to assess for possible long-term cultural *** Significant improvements were noted *** of at least one pain prevention strategy was documented at 99% of patient visits and 94% of caregivers were satisfied or very satisfied with the pain prevention care ***/caregivers reported greater satisfaction with the specific pain prevention strategy used [t(143) = 2.50,P ≤ 0.05],as well as greater agreement that the pain prevention strategies used helped their children's pain [t(180) = 2.17,P ≤ 0.05] and that they would be willing to use the same strategy again in the future [t(179) = 3.26,P ≤ 0.001] as compared to *** and caregivers also demonstrated a shift in attitudes from baseline to 1-year ***,staff reported greater agreement that the pain felt from vaccinations can result in harmful effects [2.47 vs 3.10; t(70) =-2.11,P ≤ 0.05],less agreement that pain from vaccinations is "j.st part of the process" [3.94 vs 3.23; t(70) = 2.61,P ≤ 0.05],and less agreement that parents expect their children to experience pain during vaccinations [4.81 vs 4.38; t(69) = 2.24,P ≤ 0.05].Parents/caregivers reported more favorable attitudes about pain prevention st

关键词： Pediatrics Quality improvement Distraction Pain management Immunization Vaccination Sucrose analgesia Pain prevention Non-nutritive sucking Comfort positioning Primary care

上皮生长因子对鼠肺细胞动力学的调节及其对放射保护的意义(Ⅰ)

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癌症 2003年第11期22卷 1127-1134页

作者：马骏 Andrew j.Doig Nalinin Patel 崔念基 nicholas H.A.Terry 中山大学肿瘤防治中心放射治疗科 Department of Exp Radiation Oncology M.D.Anderson Cancer CenterUniversity of TexasHoustonTexas77030-4095USA

背景与目的:上皮生长因子(keratinocyte growth factor,KGF)引起肺Ⅱ型细胞增殖,并保护肺免受外界多种刺激。以往,对慢反应正常肺组织的动力学参数难以测定,然而,近年来发展的技术使得准确测定正常组织细胞动力学指标成为可能。BrdUrd... 详细信息

背景与目的:上皮生长因子(keratinocyte growth factor,KGF)引起肺Ⅱ型细胞增殖,并保护肺免受外界多种刺激。以往,对慢反应正常肺组织的动力学参数难以测定,然而,近年来发展的技术使得准确测定正常组织细胞动力学指标成为可能。BrdUrd掺入DNA后,用流式细胞仪分析可测定组织中细胞的增殖状况,本研究的目的是采用上皮生长因子刺激后,探讨鼠肺正常组织细胞增殖动力学改变的情况。方法:采用KGF(5 mg/kg)或生理盐水C_3Hf/Kam小鼠气管内注射,并分别在0,1,2,3,4,5,及7天予以处死,处死前20分钟或6小时,腹腔内给予BrdUrd(60 mg/kg),肺组织切下后,固定于60％酒精,经消化处理形成单个细胞核,在流式细胞仪分析前行BrdUrd及总DNA含量标记染色,计算出标记指数(LI),细胞S期时间(Ts)及倍增时间(T_(pot))等细胞动力学参数;免疫荧光染色技术用于鉴定增殖细胞的类型。结果:(1)建立了上皮生长因子(5 mg/kg)刺激肺Ⅱ型细胞增殖的方法及气管内给药的途径;(2)肺组织LI由正常值0.5％升至给药后第三天的5.5％,第七天回至正常;(3)细胞T_(pot)由75.5天降至4.7天;生理盐水治疗组增殖参数没有变化。结论:上皮生长因子可引起肺Ⅱ型细胞的增殖,主要表现为LI的升高及T_(pot)降低。这种增殖效应短暂,第七天回至正常。

关键词：上皮生长因子鼠肺细胞动力学放射治疗保护作用气管内给药

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微机电系统(MEMS)惯性敏感器的性能

控制工程（北京） 1999年第5期 51-58页

作者： A.Kourepenis j.Borenstein j.connelly 潘科炎

采用先进的微加工技术生产了许多小型低成本硅惯性敏感器,这些惯性敏感器的性能高,坚固耐用,且具有其固有的对称性。这些敏感器用专用集成电路(ASIC)集成后,可封装成一个3cm见方的扁平组件,并可用5V直流单电源工作。这些敏感器已经在汽... 详细信息

采用先进的微加工技术生产了许多小型低成本硅惯性敏感器,这些惯性敏感器的性能高,坚固耐用,且具有其固有的对称性。这些敏感器用专用集成电路(ASIC)集成后,可封装成一个3cm见方的扁平组件,并可用5V直流单电源工作。这些敏感器已经在汽车防滑和牵引控制系统以及制导军械系统中通过了鉴定。利用这些多芯片模块(MCM)型仪器可使制导军械改进其海军5英寸54火炮平台的制导精度。惯性敏感器利用晶片溶解工艺制造,这种工艺利用阳极化方法将单晶硅粘结在玻璃基底上,所形成的敏感瞒模件尺寸约1mm。在-40℃到+85℃的汽车工作温度范围内,名义上经验证的未补偿的性能如下:陀螺仪的偏值和标度因子为0.5°/s和1.0%,加速度计的偏值和标度因子为30mg和0.5%。在6小时的夜间试验期间,陀螺的偏值稳定性在温度变化较小(0.5℃)时优于10°/h(0.003°/s),而相应的加速度计其偏值稳定性名义上的验证性能优于10^(-3)g。陀螺的角度随机游动典型值为0.25°/■,目前观测到的最优性能为0.05°/■,而加速度计的速度随机游动为5cm/s/■。在-40℃到+85℃的整个工作温度范围内对仪表性能进行标定和补偿后,仪表标度因子的稳定性优于200ppm,陀螺和加速度计的偏值不确定性分别小于50°/h和1mg。业已验证了这些设计对外界环境的鲁棒性,在超过60000g的环境下通过了空中火炮射击试验。本文讨论仪表实测性能和设计性能,重点介绍陀螺和加速度计的近期试验结果。文中还介绍了仪器的有关电子线路、控制装置和应用问题。

关键词：惯性敏感器导航电子线路控制装置应用

Operations management for competitive advantage / 11th ed.

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Operations management for competitive advantage /

2006年

作者： Chase Richard B.j.cobs F. Robert. Aquilano nicholas j.

来源：畅想之星图书光盘版（南... 评论

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多媒体系统与信息集散

情报科学 1994年第6期15卷 53-58页

作者： nicholas I.Benimoff Michael j.Burns 张海燕美

在过去的几十年中,计算机技术以比许多可以想象得到的速度高得多的多的速度一直在发展着。不断进取的信息传递能力已导致了在时间,地点,原因和人们如何通信等方面的诸多变化。在计算机能力方面的发展改变了我们的工作情况及个人生活的... 详细信息

在过去的几十年中,计算机技术以比许多可以想象得到的速度高得多的多的速度一直在发展着。不断进取的信息传递能力已导致了在时间,地点,原因和人们如何通信等方面的诸多变化。在计算机能力方面的发展改变了我们的工作情况及个人生活的情况。

关键词：多媒体系统信息集散计算机

Ultrafast terahertz emission from emerging symmetry-broken materials

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Light(Science & Applications) 2023年第7期12卷 1216-1245页

作者： j.cob Pettine Prashant Padmanabhan nicholas Sirica Rohit P.Prasankumar Antoinette j.Taylor Hou-Tong Chen Center for Integrated Nanotechnologies Los Alamos National LaboratoryLos AlamosNM87545USA Deep Science Fund Intellectual VenturesBellevueWA 98005USA

Nonlinear optical spectroscopies are powerful tools for investigating both static material properties and light-induced ***(THz)emission spectroscopy has emerged in the past several decades as a versatile method for directly tracking the ultrafast evolution of physical properties,quasiparticle distributions,and order parameters within bulk materials and nanoscale *** optically-induced THz radiation is often analyzed mechanistically in terms of relative contributions from nonlinear polarization,magnetization,and various transient free charge *** this offers material-specific insights,more fundamental symmetry considerations enable the generalization of measured nonlinear tensors to much broader classes of *** thus frame the present discussion in terms of underlying broken symmetries,which enable THz emission by defining a system directionality in space and/or time,as well as more detailed point group symmetries that determine the nonlinear response *** this framework,we survey a selection of recent studies that utilize THz emission spectroscopy to uncover basic properties and complex behaviors of emerging materials,including strongly correlated,magnetic,multiferroic,and topological *** then turn to low-dimensional systems to explore the role of designer nanoscale structuring and corresponding symmetries that enable or enhance THz *** serves as a promising route for probing nanoscale physics and ultrafast light-matter interactions,as well as facilitating advances in integrated THz ***,the interplay between intrinsic and extrinsic material symmetries,in addition to hybrid structuring,may stimulate the discovery of exotic properties and phenomena beyond existing material paradigms.

关键词： symmetry enable nonlinear