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生物瓣膜二尖瓣置换老年心脏瓣膜病患者血清炎性因子及血流动力学的变化 被引量:12
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作者 张杨 赵巧燕 +1 位作者 翟继卫 厉菁 《中国组织工程研究》 CAS 北大核心 2022年第10期1561-1565,共5页
背景:保留全瓣及瓣下结构的二尖瓣置换是治疗心脏瓣膜病的有效方法,其中人工瓣膜材料的选择起到至关重要的作用。目的:探讨生物瓣膜二尖瓣置换在老年心脏瓣膜病患者中的应用效果。方法:回顾性分析郑州市第七人民医院2017年5月至2019年4... 背景:保留全瓣及瓣下结构的二尖瓣置换是治疗心脏瓣膜病的有效方法,其中人工瓣膜材料的选择起到至关重要的作用。目的:探讨生物瓣膜二尖瓣置换在老年心脏瓣膜病患者中的应用效果。方法:回顾性分析郑州市第七人民医院2017年5月至2019年4月收治的老年心脏瓣膜病二尖瓣置换患者96例的临床资料,根据患者病情及意愿分为生物组62例、机械组34例。生物组进行保留全瓣及瓣下结构的生物瓣膜二尖瓣置换,机械组进行保留全瓣及瓣下结构的机械瓣膜二尖瓣置换,比较两组心功能及临床疗效、血清炎性因子、血流动力学、并发症等指标。研究已获得郑州市第七人民医院伦理委员会批准(20170315)。结果与结论:①术后随访12个月,生物组心功能美国纽约心脏病协会分级Ⅰ级占71%、临床治疗成功率为77%,机械组心功能美国纽约心脏病协会分级Ⅰ级占47%、临床治疗成功率为53%,两组间心功能分级与临床治疗成功率比较差异有显著性意义(P<0.05);两组均未发生人工瓣膜结构性衰坏所致再次手术及死亡病例,生物组患者血栓栓塞、心内膜炎、瓣周漏的发生率均低于机械组(P<0.05)。②术后3 d,生物组患者血清白细胞介素6、肿瘤坏死因子α的质量浓度均低于机械组(P<0.05),血清白细胞介素10的质量浓度高于机械组(P<0.05)。③术后随访12个月,生物组患者的二尖瓣口E峰峰值速度、平均跨压差检测结果低于机械组(P<0.05),人工瓣有效瓣口面积检测结果大于机械组(P<0.05)。④结果表明,生物瓣膜二尖瓣置换有助于改善老年心脏瓣膜病患者心功能、提高手术成功率、降低并发症,可能与拮抗炎症应激反应、改善血流动力学等因素有关。 展开更多
关键词 老年 心脏瓣膜病 生物瓣膜 机械瓣膜 二尖瓣置换 炎性应激 血流动力学
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铌酸钠基无铅陶瓷的弛豫反铁电相构筑与储能特性优化
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作者 杨伟伟 曾华荣 +2 位作者 翟继卫 赵坤宇 李国荣 《硅酸盐学报》 EI CAS CSCD 北大核心 2024年第4期1200-1210,共11页
开发具有优异综合储能特性的无铅陶瓷电容器是脉冲功率技术领域的迫切需求。相较于其他无铅储能陶瓷体系,Na Nb O_(3)(NN)陶瓷具有结构相变丰富、理论密度低、电学可调性强、轻量化发展潜力大等显著优点,因而备受关注,成为当前的研究热... 开发具有优异综合储能特性的无铅陶瓷电容器是脉冲功率技术领域的迫切需求。相较于其他无铅储能陶瓷体系,Na Nb O_(3)(NN)陶瓷具有结构相变丰富、理论密度低、电学可调性强、轻量化发展潜力大等显著优点,因而备受关注,成为当前的研究热点。基于降低容忍因子稳定反铁电相和增强陶瓷弛豫性的策略,开展了NN基弛豫反铁电陶瓷的制备与储能特性研究。通过引入BiFeO_(3)和Sr(Ti_(0.85)Zr_(0.15))O_(3)成功制备了0.9[0.9NaNbO_(3)-0.1BiFeO_(3)]-0.1Sr(Ti_(0.85)Zr_(0.15))O_(3)陶瓷,相较于纯NN陶瓷(0.14 J/cm^(3)、6.39%)和0.9NaNbO_(3)-0.1BiFeO_(3)陶瓷(3.55 J/cm^(3)和70.61%),其储能特性显著提升,储能密度(Wrec)与储能效率(η)分别达到了5.22 J/cm^(3)、83.92%。其优异的储能特性源于BiFeO_(3)和Sr(Ti_(0.85)Zr_(0.15))O_(3)掺杂对陶瓷的晶粒细化、反铁电相稳定性和弛豫特性的双增强机制。同时,0.9[0.9NaNbO_(3)-0.1Bi Fe O_(3)]-0.1Sr(Ti_(0.85)Zr_(0.15))O_(3)陶瓷表现出良好的温度及频率稳定性,是一种极具应用前景的电介质储能材料。 展开更多
关键词 铌酸钠 无铅陶瓷 反铁电 储能特性 充放电特性
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Optimization of synergistic energy storage density and efficiency for eco-friendly (Na_(0.5)Bi_(0.5))_(0.6)Sr_(0.4)TiO_(3)-based relaxor ferroelectric ceramics 被引量:1
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作者 Hu Di Pan Zhongbin +8 位作者 Wu Lukang Yang Fan Tang Luomeng Zhao Jinghao Shen Yihao Chen Yuyun Li Peng zhai jiwei Liu Jinjun 《Journal of Materiomics》 SCIE EI 2021年第4期869-878,共10页
Inspired by increasing demand of advanced pulsed power capacitors,the development of lead-free dielectric ceramic capacitors with high energy storage density and temperature-insensitive performance are extremely cruci... Inspired by increasing demand of advanced pulsed power capacitors,the development of lead-free dielectric ceramic capacitors with high energy storage density and temperature-insensitive performance are extremely crucial.Herein,the lead-free relaxor ferroelectric ceramics based on(1-x)(Na_(0.5)Bi_(0.5))0.6Sr_(0.4)TiO_(3-x)Sr_(0.7)La_(0.2)ZrO_(3)[abbreviated as(1-x)NBST-xSLZ]are prepared by the solid-state reaction route.The large recoverable energy density(Wrec)of 3.45 J/cm^(3) and efficiency(h)of 90.1%are simultaneously realized in 0.86NBST-0.14SLZ ceramic due to increased breakdown strength.Furthermore,both the Wrec and h of 0.86NBST-0.14SLZ ceramic display superior of thermal stability(20e180C),frequency stability(1e1000 Hz),and cycle stability(10^(4))within a satisfactory range of variation.In addition,the 0.86NBST-0.14SLZ ceramic can also achieve a large current density(CD)of 625 A/cm^(2),an ultrahigh power density(PD)of 50 MW/cm^(3) and a fast discharge rate(t0.90)of 160.8 ns at 160 kV/cm.These results demonstrate that the 0.86NBST-0.14SLZ ceramic could be a highly competitive and ecofriendly relaxor ferroelectric material for next-generation pulsed power capacitors. 展开更多
关键词 Lead-free ceramics Energy storage density (Na_(0.5)Bi_(0.5))_(0.6)Sr_(0.4)TiO_(3) Thermal stability Power density
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Structural and dielectric tunable properties of Ba_(0.4)Sr_(0.6)Ti_(1-y)Si_yO_3 microwave ceramics 被引量:1
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作者 ZHANG JingJi zhai jiwei WANG JiangYing 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第3期610-615,共6页
The structure-property relationships in Ba0.4Sr0.6Ti1-ySiyO3 with y=0.00,0.01,0.02,0.05,0.10 and 0.20 ceramics have been studied by using X-ray diffraction,electron microscopy and dielectric spectroscopy.An increase o... The structure-property relationships in Ba0.4Sr0.6Ti1-ySiyO3 with y=0.00,0.01,0.02,0.05,0.10 and 0.20 ceramics have been studied by using X-ray diffraction,electron microscopy and dielectric spectroscopy.An increase of Si concentration is not favorable for the stability of the perovskite structure,which results in the formation of BaTiSiO5 secondary phase.The dielectric peaks of samples are suppressed,broadened and shifted to low temperature with increasing Si concentration.Permittivity and Q value are reduced gradually with increasing Si concentration,due to growing of second BaTiSiO5 phase.The tunability(T) still remains ~18.0% under 60 kV/cm biasing for the samples with y-0.10.The best combination of microwave dielectric properties are obtained for the composition of y=0.10:-=531,Q=391(at 1.610 GHz) and T=17.7%. 展开更多
关键词 BST ceramics tunable property microwave dielectric properties
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