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Mo_2Ni_3Si／γ双相合金的显微组织及室温干滑动磨损行为研究

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金属学报 2006年第7期42卷 722-726页

作者：徐亚伟王华明北京航空航天大学材料学院激光材料加工与制造技术实验室北京100083

采用激光熔炼技术制备出镍基固溶体γ与Mo2Ni3Si三元金属硅化物双相合金,其显微组织由Mo2Ni3Si初生枝晶及枝晶间以γ相为主的γ／Mo2Ni3Si共晶组成．室温干滑动磨损实验表明,由于高硬度Mo2Ni3Si(hp12 Laves相)及强韧性基体γ相的牢固结... 详细信息

采用激光熔炼技术制备出镍基固溶体γ与Mo2Ni3Si三元金属硅化物双相合金,其显微组织由Mo2Ni3Si初生枝晶及枝晶间以γ相为主的γ／Mo2Ni3Si共晶组成．室温干滑动磨损实验表明,由于高硬度Mo2Ni3Si(hp12 Laves相)及强韧性基体γ相的牢固结合,Mo2Ni3Si／γ双相合金具有十分优异的耐磨性能,其磨损机理是硬度较低的γ／Mo2Ni3Si共晶组织被优先磨损;凸出于磨损表面的部分Mo2Ni3Si初生相失去了共晶的支撑而发生开裂及剥落;另一方面,Mo2Ni3Si初生相保护基体免于严重磨损,其磨损速率最终控制合金的总磨损速率．

关键词：金属间化合物 M02Ni3Si 双相合金磨损

激光熔化沉积γ/Mo_2Ni_3Si金属硅化物合金的腐蚀行为

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稀有金属材料与工程 2007年第4期36卷 660-664页

作者：徐亚伟王华明北京航空航天大学激光材料加工与制造技术实验室北京100083

采用极化曲线,塔菲尔图(TafelPlot),交流阻抗(EIS)及浸泡腐蚀技术,研究了激光熔化沉积γ/Mo2Ni3Si合金在不同酸,碱,盐介质中的腐蚀行为。结果表明,该合金在1mol/LNaOH溶液中,由于形成了稳定的钝化膜,耐蚀性优异;在1mol/LH2SO4溶液中,合... 详细信息

采用极化曲线,塔菲尔图(TafelPlot),交流阻抗(EIS)及浸泡腐蚀技术,研究了激光熔化沉积γ/Mo2Ni3Si合金在不同酸,碱,盐介质中的腐蚀行为。结果表明,该合金在1mol/LNaOH溶液中,由于形成了稳定的钝化膜,耐蚀性优异;在1mol/LH2SO4溶液中,合金只能形成不稳定的钝化膜;而在含Cl-的中性或酸性介质中,合金没有钝化趋势,且由浸泡腐蚀试验表明,在1mol/LHCl溶液中,由于Cl-导致相界腐蚀,合金耐蚀性较差。

关键词：金属硅化物腐蚀极化曲线交流阻抗(EIS) 浸泡腐蚀

站在历史的新起点,展望心脏病学发展的美好明天

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上海医学 2010年第5期33卷 393-394页

作者：徐亚伟同济大学附属第十人民医院心内科上海200072

心脏疾病是危害人类生命与健康最为严重的疾病之一.心脏病学发展的脚步也一刻未曾停留,近30年来更是获得了突飞猛进的发展.在基础领域,人们对高血压、动脉粥样硬化、肺动脉高压、心力衰竭等机制的认识进一步深入,尤其是对钠与高血压、... 详细信息

心脏疾病是危害人类生命与健康最为严重的疾病之一.心脏病学发展的脚步也一刻未曾停留,近30年来更是获得了突飞猛进的发展.在基础领域,人们对高血压、动脉粥样硬化、肺动脉高压、心力衰竭等机制的认识进一步深入,尤其是对钠与高血压、血脂与动脉粥样硬化、肾素-血管紧张素-醛固酮系统与心力衰竭及高血压等的关系有了深刻而细致的认识.对上述机制的了解,使人们对心脏疾病的预防从理想转为现实.中华医学会心血管病分会主任委员胡大一教授于本期发表的述评,系统地阐述了心血管疾病预防的新思路,提出要降低心血管疾病的疾病负担及死亡率,就必须将心血管疾病防治的防线前移,强调通过健康的生活方式来预防危险因素(高血压、糖尿病、血脂异常、肥胖和吸烟等),而不是传统的用药物控制危险因素,且强调预防必须从青少年抓起

关键词：心脏病学新起点动脉粥样硬化心脏疾病心力衰竭肺动脉高压醛固酮系统血管紧张素

Experience with pulmonary vein isolation in patients with paroxysmal atrial fibrillation by using a circular cryoablation catheter

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上海医学 2007年第S1期30卷 107-108页

作者： xu yawei, TANG Kai, ZHOU Ke, YU xuejing, CHEN Yanqing Department of Cardiology, Shanghai Tenth People’ s Hospital, Tongji University, Shanghai 200072, China

Objective This study was to report our early experience with electrical isolation of pulmonary vein (PV) in paroxysmal atrial fibrillation (AF) by using a circular cryoablation catheter. Methods After electroanatomic model of LA/PVs was established by Carto, cryoablation was performed in each PV. If complete isolation of PVs could not be achieved, then additional radiofrequency ablations would be applied to ablate the conduction gaps. Results Cryoablation was performed in totally 58 PVs in 14 cases with paroxysmal AF. Thirty-one PVs (53.4%) were successfully isolated with the single use of the circular cryoablation catheter after 2 to 5 (3.2±1.5) cryoablation, while 2 to 4 additional radiofrequency ablations needed to be applied at gaps on the circular cryoablation lines to achieve completely isolation in 27 PVs (46.6%). After a follow up of 18±7 months, 11 patients (78.6%) remained AF free. Selective pulmonary venography immediately and repeat magnetic resonance imaging (MRI) scan at 3 months post procedure showed there was no PV stenosis. Conclusion The circular cryoablation catheter can be safely used in the isolation of PVs in paroxysmal AF, But the efficacy of this technique needs to be further improved.

关键词： fibrillation paroxysmal isolation safely circular radiofrequency stenosis conduction immediately tot

Changes of Plasma Levels of Brain Natriuretic Peptide in Patients with Chronic Heart Failure

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South China Journal of Cardiology 2006年第2期7卷 119-121页

作者： Pei Xiaoyang Pan Yin Hu xuesong Li Song xu yawei Yu xuejing Department of Cardiology Shenzhen Fu Tian People＇s Hospital Shenzhen Guangdong 518033 China Shanghai Tenth Pepeole＇ s Hospital Shanghai 200072 China

To investigate the changes of plasma brain natriuretic peptide （BNF） levels inpatients with chronic heart failure （CHF）. Methods Plasma BNP concentrations in patients with CHF （n=56） and in normal controls （n=60） were measured with specific radioimmunoassay. Left ventricular ejection fraction in patients with chronic heart failure was measured with 99mTc gated cardiac blood pool scintigraphy. Results The results showed that Plasma BNP concentrations in patients with CHF were significantly higher than normal controls （223±79 ng/L vs 40±15 ng/L, P 〈 0.01）. Plasma BNP concentrations had a significant negative correlation with left ventricular ejection fractions（r=-0.68, P 〈 0.01 ）. Conclusions These results indicates that Plasma BNP levels are increased in patients with CHF, and they markedly increased according to the severity of heart failure classified by NYHA classifi- cation. The plasma BNP levels may be a biochemical parameter for evaluating the left ventricular function.

关键词： Brain natriuretic peptide Chronicheart failure Left ventricular ejection fractions

Twin peaks of in-hospital mortality among patients with STEMI across five phases of COVID-19 outbreak in China:a nation-wide study

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Science China(Life Sciences) 2022年第9期65卷 1855-1865页

作者： Jianping Li Nan Zhang Ziyi Zhou Xiao Huang Weiyi Fang Hongbing Yan Jiyan Chen Weimin Wang Dingcheng Xiang Xi Su Bo Yu Yan Wang yawei xu Lefeng Wang Chunjie Li Kai Huang Xiaobin Wang Yong Huo Junbo Ge Department of Cardiology Peking University First HospitalBeijing 100044China Key Laboratory of Precision Nutrition and Food Quality Ministry of EducationDepartment of Nutrition and HealthCollege of Food Sciences and Nutritional EngineeringChina Agricultural UniversityBeijing 100083China Institute of Biomedicine Anhui Medical UniversityHefei 230032China Department of Cardiovascular Medicine Second Affiliated Hospital of Nanchang UniversityNanchang 330008China Department of Cardiology Huadong Hospital Affiliated to Fudan UniversityShanghai 200050China Department of Cardiology Fuwai Hospital Chinese Academy of Medical SciencesShenzhen 518057China Department of Cardiology Guangdong Provincial People’s HospitalGuangzhou 510080China Department of Cardiology Peking University People’s HospitalBeijing 100044China Department of Cardiology General Hospital of Southern Theatre CommandGuangzhou 510010China Department of Cardiology Wuhan ASIA Heart HospitalWuhan 430010China Department of Cardiology The 2nd Affiliated Hospital of Harbin Medical UniversityHarbin 150086China Department of Cardiology Xiamen Cardiovascular Hospital Xiamen UniversityXiamen 361004China Department of Cardiology Shanghai Tenth People’s HospitalShanghai 200072China Department of Cardiology Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100069China Department of Emergency Tianjin Chest HospitalTianjin 300074China Department of Cardiology Union Hospital Affiliated to Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Population Family and Reproductive HealthJohns Hopkins University Bloomberg School of Public HealthBaltimore 21218USA Department of Cardiology Zhongshan HospitalFudan UniversityShanghai 200032China

Lockdown and re-opening may become cyclical due to the recurrent waves of the COVID-19 *** studies have examined temporal trends and determinants of in-hospital mortality among patients with ST-segment elevation myocardial infarction(STEMI),a life-threatening condition that requires emergency medical *** nation-wide data before,during and after the Wuhan lockdown,we aimed to depict temporal patterns and major determinants of STEMI in-hospital mortality in China across five time periods of the COVID-19 *** analyzed the data of 283,661 STEMI patients who were admitted to 4,487 chest-pain-centers across China,from January 1,2019 to May 31,*** with the period before the lockdown,STEMI in-hospital mortality increased by 25%(OR 1.25,95%CI 1.16–1.34)during Early Lockdown,by 12%(OR 1.12,95%CI 1.03–1.22)during Later Lockdown,by 35%(OR 1.35,95%CI 1.21–1.50)during Early Lift,and returned to pre-COVID risk(OR 1.04,95%CI 0.95–1.14)during Later *** each time-period,we observed a clear mortality gradient by timing and types of revascularization *** conclusion,the COVID-19 epidemic had a significant adverse impact on STEMI in-hospital mortality,with bimodal peaks during early lockdown and early lift periods and clear mortality gradients by timing and types of revascularization procedure,independent of the time periods.

关键词： COVID-19 STEMI mortality lockdown re-opening

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芹菜素-羟丙基-β-环糊精包合物的研究

中国农学通报 2011年第25期27卷 245-249页

作者：徐亚维吉林农业科技学院生物工程学院吉林吉林132101

为了获得芹菜素-羟丙基-β-环糊精包合物的最佳制备工艺,对其包合工艺进行研究。以包合率为指标,考察投料比、乙醇浓度、包合时间及包合温度对包合的影响,并采用正交试验优化最佳工艺。结果表明,溶液搅拌法是最佳包合方法,且投料比对包... 详细信息

为了获得芹菜素-羟丙基-β-环糊精包合物的最佳制备工艺,对其包合工艺进行研究。以包合率为指标,考察投料比、乙醇浓度、包合时间及包合温度对包合的影响,并采用正交试验优化最佳工艺。结果表明,溶液搅拌法是最佳包合方法,且投料比对包合效果的影响最大。芹菜素与羟丙基-β-环糊精的最佳包合工艺是:芹菜素与羟丙基-β-环糊精的摩尔比为1:3,乙醇浓度为50%,包合温度为50℃,包合时间为1h时,达到最好包合效果,此时按最佳工艺条件制备包合物的包合率为42.8%。通过对不同包合方法和不同包合条件进行探索,得到一条适合芹菜素-羟丙基-β-环糊精包合物的最佳制备工艺,为芹菜素的应用开发提供一点理论基础。

关键词：芹菜素 HP-β-CD 包合物正交试验

解读功能性SYNTAX积分对冠状动脉多支病变危险分层和预后评估的价值

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上海医学 2011年第5期34卷 335-336页

作者：徐亚伟王勇同济大学附属第十人民医院心内科上海200072

SYNTAX（synergy between percutaneous coronary intervation with TAxuS and cardiac surgery）研究的结果首次公布于2008年的欧洲心脏病学会议（ESC），是针对左主干病变和（或）多支病变的随机对照临床试验[1]，其一项重要贡献是提... 详细信息

SYNTAX（synergy between percutaneous coronary intervation with TAxuS and cardiac surgery）研究的结果首次公布于2008年的欧洲心脏病学会议（ESC），是针对左主干病变和（或）多支病变的随机对照临床试验[1]，其一项重要贡献是提出了SYNTAX积分的概念。SYNTAX积分是一种根据冠状动脉病变解剖特点进行危险分层的积分系统，根据病变位置、严重程度、分叉和钙化等解剖特点定量评价冠状动脉病变的复杂程度。

关键词：冠状动脉多支病变积分系统危险分层预后评估功能性随机对照临床试验冠状动脉病变价值

Phosphatase and Actin Regulator 1 Deficiency Decreases Plasma Cholesterol through Endothelial Peroxisome Proliferator-activated Receptor γ Signaling

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Phosphatase and Actin Regulator 1 Deficiency Decreases Plasm...