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1.
Xian-bao LIU Ju-bo JIANG Qi-jing ZHOU Zhao-xia PU Wei HE Ai-qiang DONG Yan FENG Jun JIANG Yong SUN Mei-xiang XIANG Yu-xin HE You-qi FAN Liang DONG Jian-an WANG 《Journal of Zhejiang University. Science. B》2015,16(3):208-214
目的:评估经导管主动脉瓣置入术在中国人群二叶式主动脉瓣重度狭窄中的安全性和有效性。创新点:首次在中国人群比较经导管主动脉瓣置入术在二叶式和三叶式主动脉瓣重度狭窄中的安全性和有效性。方法:选取2013年3月至2014年9月行经导管主动脉瓣置入术的40位主动脉瓣狭窄的患者,分二叶式和三叶式主动脉瓣两组,比较基线水平、手术以及随访1月结果的差别。结论:经导管主动脉瓣置入术在中国人群中二叶式主动脉瓣重度狭窄中的应用是安全有效的。 相似文献
2.
Wei He Rong-rong Huang Qing-yu Shi Xian-bao Liu Jian-an Wang Min Yan 《Journal of Zhejiang University. Science. B》2017,18(4):353-359
Objective
Transcatheter aortic valve implantation (TAVI) is a minimally invasive therapy for elderly patients with severe aortic valve stenosis who were refused surgical aortic valve replacement because of the high perioperative risk. Traditionally, this procedure has been done under general anesthesia, but more recently local anesthesia and sedation have become popular. This research assessed the effectiveness of transfemoral TAVI under bispectral index (BIS)-guided sedation.Methods
In this single-center retrospective control analysis, clinical data, including demographic characteristics, echocardiography, periprocedural data, and main complications, were collected and assessed in 113 patients undergoing TAVI through the femoral artery under general anesthesia (GA group, n=36) and under BIS-guided sedation (SED group, n=77).Results
The demographic characteristics and echocardiographic parameters between the two groups were similar (P>0.05). Two (2.6%) of patients were moved from BIS-guided sedation to general anesthesia for surgical reasons. Procedures were significantly shorter in the SED group than in the GA group ((127.10±44.43) min vs. (165.90±71.62) min, P=0.004). Patients in the SED group lost less blood and received significantly fewer red blood cells and catecholamines than those in the GA group (5.19% vs. 22.22%, P=0.017 and 67.53% vs. 97.22%, P<0.001). The length of hospital stay was significantly shorter and there were fewer pulmonary complications in the SED group than in the GA group. Thirty-day mortality was similar between the two groups.Conclusions
BIS-guided sedation is a feasible and safe approach for transfemoral TAVI. The anesthesiologist should choose the best anesthetic method according to the team’s experience.3.
矿物质代谢紊乱与钙化性主动脉瓣疾病的发生和严重性相关（英文） 总被引：1，自引：0，他引：1
Zhen-kun YANG Chen YING Hong-yan ZHAO Yue-hua FANG Ying CHEN Wei-feng SHEN 《Journal of Zhejiang University. Science. B》2015,16(5):362-369
目的:探讨在肾功能正常或轻度受损(肾小球滤过率≥60 ml/(min·1.73 m2))人群中矿物质代谢紊乱与钙化性主动脉瓣疾病的发生和严重性是否相关。创新点:以具有代表性和临床价值的肾功能正常或轻度受损人群为研究对象,首次尝试通过骨转换生物标志物检测探讨钙化性主动脉瓣疾病的可能机制。方法:入选260例经超声心动图诊断钙化性主动脉瓣疾病患者(164例钙化性主动脉瓣硬化,96例钙化性主动脉瓣狭窄)和164例年龄及性别匹配对照组人群,检测矿物质代谢和骨转换生化标志物,应用多因素回归分析矿物质代谢与钙化性主动脉瓣疾病的发生和严重性的关系,并初步探讨可能机制。结果显示,从对照组到钙化性主动脉瓣硬化至狭窄患者,血钙、血磷、碱性磷酸酶和甲状旁腺素(i PTH)水平进行性升高,25羟-维生素D(25-OHD)水平进行性降低,各组间差异具有统计学显著性(P<0.001);同样,骨转换生化标志物骨钙素(BGP)、I型前胶原N端前肽(PINP)和β-胶原特殊序列(β-CTx)水平进行性升高,各组间差异具有统计学显著性(P<0.001)。在钙化性主动脉瓣狭窄患者中,i PTH水平与跨瓣峰值流速和平均跨瓣压差显著正相关,25-OHD则显著负相关。经校正相关因素后,多因素回归分析显示,血钙、血磷、碱性磷酸酶和i PTH水平升高及25-OHD水平下降和钙化性主动脉瓣疾病的发生和严重性密切相关。结论:矿物质代谢紊乱与钙化性主动脉瓣疾病的发生和严重性密切相关,异常骨转换可能是其发生机制。 相似文献
4.
Jiaqi FAN Changjie YU Kaida REN Wanbing LIN Stella NG Zexin CHEN Xinping LIN Lihan WANG Qifeng ZHU Yuxin HE Jubo JIANG Xianbao LIU Jian'an WANG 《Journal of Zhejiang University. Science. B》2021,22(3):241-247
Aortic stenosis(AS)is a progressive heart valve disease occurring predominantly in older patients.According to a survey in a western country,the prevalence of AS is nearly 6.4%in patients over 75 years old(Carabello and Paulus,2009).Transcatheter aortic valve replacement(TAVR)is an alternative method for AS patients.Previous studies have described how up to 66%of TAVR patients have concomitant baseline kidney dysfunction(Ferro et al.,2015;Gargiulo et al.,2015).The majority of patients can benefit from the TAVR procedure with the recovery of kidney function. 相似文献
5.
Transcatheter valve implantation or repair has been a very promising approach for the treatment of valvular heart diseases since transcatheter aortic valve implantation (TAVI) was successfully performed in 2002. Great achievements have been made in this field (especially TAVI and transcatheter mitral valve repair—MitraClip system) in recent years. Evidence from clinical trials or registry studies has proved that transcatheter valve treatment for valvular heart diseases is safe and effective in surgical high-risk or inoperable patients. As the evidence accumulates, transcatheter valve treatment might be an alterative surgery for younger patients with surgically low or intermediate risk valvular heart diseases in the near future. In this paper, the updates on transcatheter valve treatment are reviewed. 相似文献
6.
分析了液压阀汽蚀产生的原因以及给液压阀带来的影响;给出了防止汽蚀破坏液压阀的方法,以延长液压阀的使用寿命,保证液压阀的可靠性. 相似文献
7.
Jin-yuan Qian Bu-zhan Liu Zhi-jiang Jin Jian-kai Wang Han Zhang An-le Lu 《浙江大学学报(A卷英文版)》2016,17(1):54-64
The pilot-control globe valve (PCGV) is a novel globe valve with a piston-type valve core and a small pilot valve. It can utilize a pressure difference to control the state of the main valve by the pilot valve. In this paper, a mathematical model of PCGV is established and a computational fluid dynamics (CFD) method is used to numerically simulate its flow and cavitation characteristics. Analysis of the pressure difference between the upside and downside of the valve core and comparison with similar previous work increase the reliability of the simulation. Then an analysis of flow and cavitation characteristics is carried out with three comparisons: a comparison between opened and closed states, a comparison between different inlet velocities, and a comparison between different valve core displacements. The results demonstrate that the vapor volume fraction reaches its peak point at the valve seat near the outlet tube, and that a higher inlet velocity or smaller valve core displacement can cause greater cavitation damage. This study can help further design work for optimization and engineering applications of PCGV. 相似文献
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9.
介绍了阀门远传机构安装过程中,套管预埋、阀门定位、远传机构组装等关键工序,分析了定位、接口和工序质量问题产生的原因,认为应采取的改进措施为:细化施工图纸,使远传机构制造标准化,提高技术交底工作效率. 相似文献
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11.
通过对DA阀的控制原理进行系统分析,论证了其利用DA阀的自动调节作用,可以始终保持液压泵扭矩与发动机的输出扭矩的最佳匹配,防止了机械系统发动机因负载过大而熄火,并提高了使用效率,同时也减轻操作者的心理负担.DA阀在机械行业必将得到越来越广泛应用. 相似文献
12.
根据溢流阀的特点,以Y2-Hc10型先导式溢流阀为阀体,设计了并联型及开关切换型模糊PID控制的数字溢流阀系统并建立数学模型。通过Matlab的仿真表明,两种模糊PID控制的数字溢流阀响应速度快、精度高,控制效果较好。 相似文献
13.
首先对雷电流的波形进行分析,然后对雷电流的脉冲函数模型进行傅里叶变换,得出雷电流的频谱函数、雷电流峰值比率的频谱及雷电流峰值比率积累的频谱,在给定波形的条件下绘出雷电流的频谱图、雷电流峰值比率的频谱图及雷电流峰值比率积累的频谱图,然后找出雷电危害的重要波段所在。这对雷电防护装置的设计具有重要的指导意义。 相似文献
14.
气垫阀的性能,很大程度上取决于阀隙马赫数、气阀升程、气阀弹簧力和气阀呼吸孔直径等主要性能参数的设计选取。本文介绍了设计气垫阀时选择这些主要参数的基本原理和方法。根据我国目前的实际和资料,介绍了气垫阀设计时确定这些主要参数的曲线图和计算公式,为气垫阀的设计计算提供了依据。 相似文献
15.
罗国昌 《九江职业技术学院学报》2012,(3):18-20
对于小型阀体内孔的车削加工,通常会采用角铁式车夹具装夹加工,本文采用不同于通常的角铁式车夹具的方孔定位夹紧夹具装夹加工;同时,利用阀体零件自身的螺纹孔进行定位夹紧加工。二者结合,使得夹具制作简单,加工方便,阀体内孔精度要求更容易保证。 相似文献
16.
Angiotensin II (AngII) is the primary bioactive peptide of the renin angiotensin system that plays a critical role in many
cardiovascular diseases. Subcutaneous infusion of AngII into mice induces the development of abdominal aortic aneurysms (AAAs).
Like human AAAs, AngII-induced AAA tissues exhibit progressive changes and considerable heterogeneity. This complex pathology
provides an impediment to the quantification of aneurysmal tissue composition by biochemical and immunostaining techniques.
Therefore, while the mouse model of AngII-induced AAAs provides a salutary approach to studying the mechanisms of the evolution
of AAAs in humans, meaningful interpretation of mechanisms requires consideration of the heterogeneous nature of the diseased
tissue. 相似文献
17.
This paper has introduced the developments of water hydraulic axial piston equipments.According to the effects of physicochemical properties of water on water hydraulic components,a novel valve plate for water hydraulic axial motor has been put forward,whose moment exerted by the fluid field between valve plate and bearing plate is balanced entirely.The material screening experiment of valve plate is done on the test rig.Through numerical simulation the effects of some geometry parameters on the performance of water hydraulic motor have been studied.The silencing grooves on the valve plate in water hydraulic motor can reduce the pressure shock and the occurrence of cavitation effectively.It is evident that the appropriate structure should change the wear status between matching paris and reduces the wear and specific pressure of the matching pairs.The specimen with the new type valve plate is used in a tool system. 相似文献
18.
液晶光阀系统中γ校正探究 总被引：1，自引：0，他引：1
探究了液晶光阀系统中γ校正的原理,提出了一个等效模型来模拟γ校正,设计了一种Windows画板造色法替代颜色变化的实验验证方法,探究了在相同理论灰度下不同颜色对γ校正的影响,作了若干归纳,进行了一定的探讨,取得了较满意的结果. 相似文献
19.
As life expectancy increases, valvular heart disease is becoming more common. Management of heart disease and primarily valvular
heart disease is expected to represent a significant proportion of healthcare provided to the elderly population. Recent years
have brought a progression of surgical treatments toward less invasive strategies. This has given rise to percutaneous approaches
for the correction of valvular heart disease. Percutaneous mitral valve repair using the MitraClip system (Abbott Vascular,
Santa Clara, CA, USA) creates a double orifice and has been successfully used in selected patients with mitral regurgitation.
We review the rationale, procedural aspects, and clinical data thus far available for the MitraClip approach to mitral regurgitation. 相似文献
20.
为了降低柴油机氮氧化物(NOx)的排放、对发动机性能进行准确控制,研发了一种发动机废气再循环(EGR)新型控制系统,并对其硬件和软件进行了深入分析.测试结果显示,氮氧化物的排放量有了显著降低,验证了系统硬件和软件的有效性. 相似文献