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In vitro and in vivo degradation behavior of Mg-0.45Zn-0.45Ca(ZX00)screws for orthopedic applications

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Bioactive Materials 2023年第10期28卷 132-154页

作者： Diana C.Martinez Anna Dobkowska Romy Marek Hanna Cwieka Jakub Jaroszewicz Tomasz Płocinski Crtomir Donik Heike Helmholz Berengere Luthringer-Feyerabend Berit Zeller-Plumhoff Regine Willumeit-Romer wojciech swięszkowski Biomaterials Group Materials Design DivisionFaculty of Materials Science and EngineeringWarsaw University of TechnologyWołoska 14102-507WarsawPoland Department of Orthopedics and Traumatology Medical University of GrazAuenbruggerplatz 58036GrazAustria Institute of Metallic Biomaterials Helmholtz-Zentrum Hereon GmbH21502GeesthachtGermany Department of Physics and Chemistry of Materials Institute of Metals and TechnologyUniversity of Ljubljan1Lepi Pot 11SI-1000Ljubljan1Slovenia

Magnesium (Mg) alloys have become a potential material for orthopedic implants due to their unnecessary implant removal, biocompatibility, and mechanical integrity until fracture healing. This study examined the in vitro and in vivo degradation of an Mg fixation screw composed of Mg-0.45Zn-0.45Ca (ZX00, in wt.%). With ZX00 human-sized implants, in vitro immersion tests up to 28 days under physiological conditions, along with electrochemical measurements were performed for the first time. In addition, ZX00 screws were implanted in the diaphysis of sheep for 6, 12, and 24 weeks to assess the degradation and biocompatibility of the screws in vivo. Using scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDX), micro-computed tomography (μCT), X-ray photoelectron spectroscopy (XPS), and histology, the surface and cross-sectional morphologies of the corrosion layers formed, as well as the bone-corrosion-layer-implant interfaces, were analyzed. Our findings from in vivo testing demonstrated that ZX00 alloy promotes bone healing and the formation of new bone in direct contact with the corrosion products. In addition, the same elemental composition of corrosion products was observed for in vitro and in vivo experiments;however, their elemental distribution and thicknesses differ depending on the implant location. Our findings suggest that the corrosion resistance was microstructure-dependent. The head zone was the least corrosion-resistant, indicating that the production procedure could impact the corrosion performance of the implant. In spite of this, the formation of new bone and no adverse effects on the surrounding tissues demonstrated that the ZX00 is a suitable Mg-based alloy for temporary bone implants.

关键词： Magnesium alloys Biodegradable implants Microstructure Electron microscopy Corrosion layers

50th Anniversary of Artttlclal Cells:Evolving to Oxygen Carders,Oxygen Therapeutics,Nano artificial RBC and a Novel Oxygen Carrier with Platelet-like function

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50th Anniversary of Artttlclal Cells:Evolving to Oxygen Card...

第十一届国际人工血液大会

作者： Thomas Ming swi Chang O.C. M.D.C.M.Ph.D.FRCP[C]FRS[C]DirectorArtificial Cells ＆ Organs Research CentreDepartments of PhysiologyMedicine ＆ Biomedical EngineeringFaculty of MedicineMcGill UniversityMontrealQCCanada.H3G 1Y6

＜正＞Artificial cells were first reported 50th years ago1,*** ideas are being used increasing in the modern era of biotechnology,nanomedicine,regenerative medicine,blood substitutes, cell/stem cell therapy and even nanorobatics 3,4,***,this lecture will be on blood substitutes starting with a very brief overview of hemoglobin based blood substitutes

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人工细胞研究

国际生物医学工程杂志 1987年第6期 328-330页

作者： Thomas Ming swi Chang 陆茉珠

自1957年人工细胞的可行性首次被证明以来,研究探索剧增,使其趋于实用。现在利用新的合成材料或生物材料可以制备具有各种渗透性、表面性能和血液相容性的人工细胞。人工细胞内能包含许多物质。这些物质包括酶系统、细胞提取物、生物细... 详细信息

自1957年人工细胞的可行性首次被证明以来,研究探索剧增,使其趋于实用。现在利用新的合成材料或生物材料可以制备具有各种渗透性、表面性能和血液相容性的人工细胞。人工细胞内能包含许多物质。这些物质包括酶系统、细胞提取物、生物细胞、能吸引同位素的物质、抗原、抗体、疫苗、激

关键词：人工细胞酶系统包囊肝衰竭白蛋白肝昏迷肝疾病血液灌流血液相容性

用固定化的多酶系统和葡聚糖-NAD^+的合成单元制备必需的L-支链氨基酸

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氨基酸杂志 1992年第1期14卷 59-62,18页

作者： Kong Fu Gu Thomas Ming swi Chang 徐宁宁

我们制备的合成单元,每种都含有亮氨酸脱氢酶,尿素酶,可溶性的葡聚糖和下列辅酶再生脱氢酶:葡萄糖脱氢酶,酵母酒精脱氢酶、苹果酸脱氢酶或乳酸脱氢酶。合成细胞被填充在一个小柱里,随着葡聚糖-NADH的产生,L亮氨酸,L缬氨酸和L异亮氨酸相... 详细信息

我们制备的合成单元,每种都含有亮氨酸脱氢酶,尿素酶,可溶性的葡聚糖和下列辅酶再生脱氢酶:葡萄糖脱氢酶,酵母酒精脱氢酶、苹果酸脱氢酶或乳酸脱氢酶。合成细胞被填充在一个小柱里,随着葡聚糖-NADH的产生,L亮氨酸,L缬氨酸和L异亮氨酸相继产生。得率的最大值依赖于所用的辅酶产生系统。对于D葡萄糖和葡萄糖脱氢酶系统,得率为83～93％;对于乙醇和酵母酒精脱氢酶系统,得率为90％;对于L-苹果酸和苹果酸脱氢酶系统,得率为45～55％;对于L乳酸和乳酸脱氢酶系统,得率为64～78％。本文还进行了动力学实验,表观Km值如下:α-酮异己酸(KIC),0.33mM;α-酮异戍酸(KIV),0.51mM;DL α-酮-β-甲基-η-戊酮(KMV),0.58mM;尿素,3.52mM;D-葡萄糖,27.82mM;乙醇,3.89mM;L苹果酸3.02mM;L乳酸16.67mM。动力学分析表明,在亮氨酸脱氢酶催化的反应中,KIC,KIV和KMV都是竞争性抑制物,它们的抑制系数是和Km值相关的。

关键词： L-支链氨基酸多酶系统葡聚糖-NAD

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超声波在有机氟化学中的应用

现代化工 1987年第3期 22-25页

作者：邹纪鲁李穗湖北师范学院

综述了近年来超声波用于有机氟化学的进展,包括:羰基的全氟烷基化、炔烃和二烯烃的氢全氟烷基化、卤代烃的全氟烷基化以及不对称诱导全氟烷基化等。

关键词：氟烷基化反应溶剂卤代烃有机卤素化合物全氟烷基有机氟化学化学合成有机合成烯丙基卤脂肪族不饱和烃炔烃超声波作用 THF 偶联反应有机氟化物二烯烃光学活性

Gastrointestinal and hepatic manifestations of COVID-19 infection:Lessons for practitioners

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World Journal of Meta-Analysis 2020年第5期8卷 348-374页

作者： Syed B Pasha Ahmed swi Ghassan M Hammoud Department of Internal Medicine University of MissouriColumbiaMO 65212United States Division of Gastroenterology and Hepatology University of Missouri School of MedicineColumbiaMO 65212United States

Originating from Wuhan in China,coronavirus disease 2019(COVID-19)spread globally within months and was declared a pandemic by World Health Organization in March 2020,making it one of the biggest healthcare calamities of our *** more data on COVID-19 infection became available,what was initially thought to be a simple respiratory illness was found to be more *** extra-pulmonary manifestations are now frequently reported for COVID-19 in available literature,most commonly gastrointestinal and hepatopancreatobiliary *** to early scarcity of data,extra pulmonary manifestations were initially overlooked and may have contributed to nosocomial spread of the ***,especially gastroenterologists,who frequently encounter patients with these symptoms,need to be aware of *** can not only help minimize the nosocomial spread,ensure safety of provider but also help conserve already stretched-thin healthcare resources.A tremendous amount of COVID-19 related literature is getting added to the growing pool every day,making it difficult for providers to *** aim of our review is to summarize the available evidence for gastrointestinal and hepatopancreatobiliary manifestations of *** here briefly discussed the possible pathophysiologic mechanism for these manifestations and summarized the recommendations put forward by multiple gastrointestinal societies regarding safe and effective clinical practice during the ongoing pandemic.

关键词： COVID-19 Severe acute respiratory syndrome Coronavirus Angiotensin converting enzyme Gastrointestinal Liver

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人造细胞

国外科技新书评介 2008年第9期 11-11页

作者： Thomas Ming swi Chang 徐素宏不详中国科学院遗传与发育生物学研究所博士生

本书是至今为止对人造细胞以及相关领域最为全面的概述。作为该书的作者，Thomas Ming swi Chang，加拿大的华人科学家，有着对人造细胞深厚的造诣。从他第一次设计人造红血球细胞到现在50多年的时间里，他一直活跃于这一领域。在这本... 详细信息

本书是至今为止对人造细胞以及相关领域最为全面的概述。作为该书的作者，Thomas Ming swi Chang，加拿大的华人科学家，有着对人造细胞深厚的造诣。从他第一次设计人造红血球细胞到现在50多年的时间里，他一直活跃于这一领域。在这本书中，作者从当初对人造细胞不可思议的想法娓娓道来；像叙述历史一样讲述了人造细胞从简单的构思到复杂的分子机制以及应用的经历，并且预测了今后人造细胞的发展方向。

关键词：人造细胞华人科学家分子机制加拿大红血球作者

色氨酸和酸化剂对仔猪蛋白质消化率、蛋白质沉积和脑组织中血管收缩素浓度的影响

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饲料与畜牧（新饲料） 2008年第2期 60-60页

作者： B. Pastuszewska D. Tomaszewska-Zaremba L. Buraczewska E.swi ech M. Taciak 李亚君(译) 刘泉雨(校)

本试验主要研究了在仔猪饲料中添加结晶色氨酸和酸化剂后，仔猪机体对色氨酸的利用情况和大脑中血管收缩素的合成量的影响。本研究共进行了2个试验。在色氨酸缺乏的日粮中添加3g／kg的酸化剂（由磷酸，柠檬酸和反丁烯二酸组成的混合酸... 详细信息

本试验主要研究了在仔猪饲料中添加结晶色氨酸和酸化剂后，仔猪机体对色氨酸的利用情况和大脑中血管收缩素的合成量的影响。本研究共进行了2个试验。在色氨酸缺乏的日粮中添加3g／kg的酸化剂（由磷酸，柠檬酸和反丁烯二酸组成的混合酸制剂），对蛋白质和氨基酸的回肠表观消化率没有影响，但是当色氨酸的含量从0．65g／kg提高到0．73g／kg时色氨酸回肠表观消化率有显著变化。

关键词：蛋白质消化率仔猪饲料血管收缩色氨酸酸化剂蛋白质沉积脑组织表观消化率

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