登录

双语推荐：瓣膜

进入期刊文章
人工心脏瓣膜是治疗瓣膜性心脏病的关键。本文总结了机械瓣膜、生物瓣膜和组织工程心脏瓣膜的研究进展，并指出了人工心脏瓣膜亟待解决与提高的诸多问题，展望了人工心脏瓣膜未来的发展方向。
Artificial heart valve was the key to treatment of valvular heart disease. The research progress of mechanical valves, bioprosthetic valves and tissue-engineering heart valves were summarized, and the problems of artificial heart valve which need to be solved and improved were noted. Then the trends of artificial heart valve in the future were prospected.

[ 可能符合您检索需要的词汇 ]

进入期刊文章
自体心脏瓣膜为无神经元控制，在多物理场因素引导下，血液流动场、瓣膜和腱索之间相互作用运动，保持血流单向流动。经临床研究表明，患者植入瓣膜后的瓣膜并发症及患者生存率，与瓣膜结构、血流流场密切相关，对此评价瓣膜的血流动力学性能对改进瓣膜结构具有重要作用。自制新型曲面双叶型机械瓣膜，通过理论解析和瞬态流固耦合模拟分析讨论瓣膜最大开启时瓣膜的血流动力学性能；并在体外动态仿真环境下，对曲面型双叶瓣膜进行血流动力学测试，采用Vivitest脉动流实验平台测量，通过测试瓣膜压力、开口面积、返流量等物理量来衡量瓣膜在主动脉位置的使用性能。最后研究同 St.Jude 双叶瓣和国内 GK瓣等同类机械瓣的动力学性能作对照，根据评价结果前瞻性地研究双叶曲面机械瓣结构性能。结果表明，研制的新型曲面瓣膜具有优良的血流动力学特性。
Heart valves which could provide unidirectional function of the blood are autologous valves without nerve control.Under the multi physics factors,the basic movements of the heat valves are directed by blood flow fields and the interaction of valve and tendons.In the clinical study,the patients''survival rate and the inci-dence of valvular complications all closely depend on the blood flow fields of the heart valve,thus the evaluation of the hemodynamics of the heart valves was critical important.In this paper,thought the theoretical analysis and transient fluid-structure interaction simulation hemodynamic performance of the valve;then tested the self-design curved bileaflet mechanical heart valves under the simulation of dynamic human body environment to measure the hemodynamic of the curved bileaflet heart valve.The utility of pulsating flow experiment makes the evaluation of the performance of artificial mechanical heart valve more effective.The valves''functions,such as va

[ 可能符合您检索需要的词汇 ]

进入期刊文章
目的研究Th17/Treg细胞是否参与主动脉瓣膜钙化及其与瓣膜钙化发生相关的可能机制。方法人主动脉瓣膜组织分为3组（n=10）：（1）对照组：瓣膜来自扩张型心肌病需心脏移植的受体,排除瓣膜组织病理改变者;（2）纤维化组：瓣膜来自严重主动脉瓣膜钙化需瓣膜置换术者,取远离瓣膜钙化部位,纤维化增生组织,排除风湿热及心内膜炎病史者;（3）钙化组：瓣膜来源同纤维化组,取瓣膜明显钙化组织。分别进行von kossa染色、免疫组织化学分析,用于进一步指导瓣膜组织分组;RT-PCR分析,检测瓣膜组织内Th17/Treg细胞浸润情况。结果对照组无Th17/Treg细胞浸润;纤维化组Th17细胞浸润明显高于钙化组（0.904±0.079比0.445±0.057,P〈0.01）;钙化组Treg细胞浸润明显高于纤维化组（0.900±0.058比0.396±0.032,P〈0.01）。结论主动脉瓣膜钙化与纤维化组织中Th17/Treg细胞比率不同,调控Th17/Treg细胞分化趋势或许可以干预主动脉瓣膜钙化进程。
Objective To study whether Th17/Treg cell taking part in the development of aortic valve ( AV) calcification. Methods The tissue of AV was divided into three groups ( n =10 ): control group, fibrous degeneration group and calcification group. Valve tissue in control group was taken from patients being subject to heart transplantation because of dilated cardiomyopathy, excluding valves with pathological change. Valve tissue in fibrous degeneration group was taken from location being away from calcification change, only fibrous thickening in patients being subject to valve replacement because of severe AV calcification, and excluding patients with rheumatism and endocarditis. Valve source in calcification group was the same of fibrous degeneration group, but taken from location being obvious calcification. Every sample was tested by von kossa stain or immunohistochemistry analysis and reverse transcription polymerase chain reaction ( RT-PCR ) . Results Th17/Treg cells were not present in

[ 可能符合您检索需要的词汇 ]

进入期刊文章
背景：现有的生物瓣膜主要分为有支架和无支架两种。有支架瓣膜方便了手术操作，容易植入，植入后发生关闭不全的可能性小，但这种瓣膜并没有很好的模拟天然瓣膜。目的：为缩短瓣膜植入时间，进一步改善瓣膜性能，在参考猪主动脉根构型优化瓣膜设计的基础上，开发一种新型的适合单层缝合置入的无支架猪主动脉瓣膜，体外测试评估其性能。方法：①制备适合单层缝合的无支架猪主动脉瓣。②采用自行设计的新型单层缝合方法进行离体瓣膜植入实验。③对新型瓣膜进行体外流体力学测试及疲劳测试。结果与结论：适合单层缝合的无支架瓣膜在设计中去除了硬质的瓣架，可减轻血流冲击对瓣叶的损害，同时去除硬质瓣环后手术时可以植入口径更大的瓣膜，改善了血流动力学，较传统双层缝合瓣膜缩短了植入时间。经体外流体力学测试及疲劳测试，结果满意。但无支架生物瓣膜植入手术操作时间长、术后长期临床效果及耐久性尚需进一步临床结果验证。
BACKGROUND:The artificial heart valve used in clinical application can be divided into stented and stentless. Stented valve is convenient for operations, with a low possibility of incompetency after transplantation. However stented valve cannot stimulate natural valve. OBJECTIVE:To reduce valve implantation time and improve valve properties, this study was designed to develop a new stentless porcine aortic valve for single-layer suture and implantation based on the design of valve in pig aortic root geometry optimization, and to further evaluate its performance by in vitro test. METHODS:(1) Stentless porcine aortic valve for single-layer suture was prepared. (2) The in vitro valve implantation experiment was performed with monolayer suture method. (3) The valve was detected by in vitro fluid mechanics test and fatigue test. RESULTS AND CONCLUSION:Stentless valve for single-layer suture has removed the valve hard, which contributes to reduce the damaged caused by blood flow on the valve

[ 可能符合您检索需要的词汇 ]

进入期刊文章
该文构建一种人工生物瓣膜模型和血液流体模型，利用罚函数法建立瓣膜与血液间的耦合，利用ANSYS软件分析心循环下人工生物瓣膜力学特性。分析结果表明．应力集中于缝合边与结合边交界处．此种瓣膜应力分布均匀。同时．瓣膜完全开启时间与实际测量数据吻合．血液流速峰值在生理范围内。该模型为提供更加真实心循环下瓣膜力学特性打下基础．为下一步优化设计人工生物瓣膜提供便利。
This paper constructs numerical models of bioprosthetic heart valve and blood. Thefluid solid interaction is carried out using penalty function method. The mechanical property of the bioprosthetic heart valve during cardiac cycle is simulated with ANSYS software. Results show that the Von Mises stress concentrates at the junction of attachment edge and coaptation edge. The open time of bioprosthetic heart valve is consistent with that of actural measurement. The peak velocity of blood is in the range of physiology. This model provides more realistic mechanical property of bioprosthetic heart valve during cardiac cycle compared to pure solid model, and facilitates design and optimization of bioprosthetic heart valve.

[ 可能符合您检索需要的词汇 ]

进入期刊文章
为评价新型瓣膜的开闭状态及疲劳特性,采用TH—2200型人工心瓣疲劳寿命测试仪对聚甲醛瓣叶的双叶心脏瓣膜和ON-X心脏瓣膜进行疲劳实验,并利用高速摄像机对瓣膜的开启与关闭情况进行跟踪,考察瓣膜的瞬时运动状态.实验结果发现,在体外加速疲劳实验中,新型双叶心脏瓣膜与ON-X心脏瓣膜在相同频率下具有相近的开启关闭周期,在瓣叶开启至极限位置时都有抖动产生,该瓣膜经3×108次疲劳测试后,瓣环无明显磨损,瓣叶转动灵活,心瓣正常工作.
In order to evaluate the opening and closing states and fatigue properties of a new type of polyoxymethylene heart valve,accelerated fatigue tests were performed on the polyoxymethylene heart valve and an ON-X heart valve using the heart valve prostheses fatigue tester (TH-2200 ). The opening and the closing positions of the leaflets were tracked using the high speed camera, and the instantaneous motion states of valves were investigated. The results show that the new heart valve had a similar opening-closing cycle at the same frequency with the ON-X heart valve in in vitro accelerated fatigue experiments,and the leaflets of both the valves would generate jitters when they opened to the limit position. After 3 × 108 cycles of fatigue tests,no obvious wear was found on the valve ring,the valve leaflets rotated flexibly,and the heart valve was working properly.

[ 可能符合您检索需要的词汇 ]

进入期刊文章
背景：目前临床上应用的心脏生物瓣和机械瓣都存在一些缺陷和不足，而组织工程心脏瓣膜有可能避免这些问题的出现，成为瓣膜替代物的理想选择。 目的：探讨构建组织工程心脏瓣膜的实验研究进展。 方法：应用数据库检索的方法分析关于组织工程心脏瓣膜的实验研究文献，组织工程心脏瓣膜的三大要素为种子细胞、支架材料和细胞种植。 结果与结论：心脏瓣膜修复和置换是目前治疗心脏瓣膜性疾病的主要外科手段。目前，主要用于构建组织工程心脏瓣膜的种子细胞有血管内皮细胞、内皮祖细胞以及骨髓间充质干细胞等。经脱细胞处理的支架具有良好的生物力学性能和组织相容性，细胞种植后支架表面会形成一层连续的细胞层，其构建的组织工程心脏瓣膜是可行的。组织工程心脏瓣膜有着良好的应用前景，但目前还有很多问题需要解决，还处于研究的初级阶段。
BACKGROUND:Current cardiac bioprostheses and mechanical valves are shown to have some flaws and shortcomings, and tissue-engineered heart valves which can avoid these problems are becoming an ideal choice for valve replacement. OBJECTIVE:To explore the experimental progress in the construction of tissue-engineered heart valves. METHODS:Experimental studies related to tissue-engineered heart valves were retrieved in databases. Three main elements for tissue-engineered heart valves are seed cells, scaffold materials, and cellseeding. RESULTS AND CONCLUSION:Cardiac valve repair and replacement is the primarily surgical treatment for valvular heart disease. At present, seed cells mainly for construction of tissue-engineered heart valves include vascular endothelial cells, endothelial progenitor cells and bone marrow mesenchymal stem cells. The acellular scaffold has good biomechanical properties and histocompatibility. After cellseeding, a continuous celllayer wil form on the scaffold surf

[ 可能符合您检索需要的词汇 ]

进入期刊文章
背景：应用机械瓣和生物瓣行瓣膜置换是治疗终末期瓣膜病的有效手段，然而他们的临床应用受到多个因素的限制。具备生物活性的组织工程心脏瓣膜有潜力克服机械瓣和生物瓣的不足，选择适宜的种子细胞是组织工程心脏瓣膜研究的一个重要方面，许多成熟的体细胞和干细胞已被用于构建组织工程心脏瓣膜，然而尚未获得理想的结果。 目的：以构成瓣膜的细胞成分为基础，对用于构建组织工程心脏瓣膜的种子细胞、体外细胞种植方法的研究进行综述。 方法：由第一作者基于PubMed数据库和万方数据库应用计算机检索2000年1月至2012年12月相关的文章，英文检索词为“Tissue engineering，Heart valves，Cel”，中文检索词为“组织工程，心脏瓣膜，细胞”，优选文章内容与组织工程心脏瓣膜种子细胞直接相关，具备针对性和权威性，发表在权威杂志的文章共39篇进行综述。 结果与结论：瓣膜的细胞成分主要是内皮细胞和间质细胞，早期人们常用内皮细胞和成纤维细胞构建组织工程瓣膜，随着干细胞研究的深入，应用搏动性生物反应器种植间充质干细胞具有构建的组织工程瓣膜的潜力。
BACKGROUND:Application of mechanical valve and bioprosthetic valve replacement is an effective means for the treatment of end-stage valve disease. However, their clinical application is constrained by multiple factors. Tissue-engineered heart valves with biological activity hold the potential to overcome the defect of the mechanical valves and bioprosthetic valves. Choosing appropriate cells for cellseeding is a significant aspect for the research of tissue-engineered heart valves. A growing number of somatic cells and stem cells have been used for construction of tissue-engineered heart valves, however, not yet achieve the desired result. OBJECTIVE:To review the studies on seed cells for tissue-engineered heart valves and the cellseeding methods in vitro on the basis of the cellular components of heart valves. METHODS:First author searched PubMed and Wanfang database with computer for related articles published from January 2000 to December 2012. The keywords were“tissue engineering,

[ 可能符合您检索需要的词汇 ]

进入期刊文章
发育成熟的心脏瓣膜是由一层内皮细胞包裹的高度有序的细胞外基质和瓣膜间质细胞组成。心脏瓣膜的细胞外基质根据对瓣叶和支撑结构的不同生物学性能可以分为三类:富弹性蛋白层、富粘蛋白层和富胶原蛋白层。信号转导通路在原始瓣膜形成及瓣膜结构功能的持续维持上起着至关重要的作用。动物模型为研究瓣膜发育及其相关疾病过程提供了很重要的支持。瓣膜疾病是一个具有重要意义的公共卫生健康问题,越来越多的证据显示畸形发育是其发病机制的一个基础。未来需要更多更深层次的研究来探索调节瓣膜发育各个机制途径的相互作用,从而为新的疗法的诞生奠定基础。
The mature heart valves are made up of highly organized extracellular matrix (ECM) and valve interstitial cells (VICs) surrounded by an endothelial cell layer. The ECM of the valves is stratified into elastin-, proteoglycan-, and collagen-rich layers that confer distinct biomechanical properties to the leaflets and supporting structures. Signaling pathways have critical functions in primary valvulogenesis as well as the maintenance of valve structure and function over time. Animal models provide powerful tools to study valve development and disease processes. Valve disease is a significant public health problem, and increasing evidence implicates aberrant developmental mechanisms underlying pathogenesis. Further studies are necessary to determine regulatory pathway interactions underlying valve pathogenesis in order to generate new avenues for novel therapeutics.

[ 可能符合您检索需要的词汇 ]

进入期刊文章
目的：比较经过深低温保存不同时限对心脏瓣膜生物力学的影响。促进生物瓣膜保存技术的提高。方法：制备5组主动脉瓣膜，通过程序性降温后置于深低温液氮中(-196℃)储存，经过2周、4周、6周、8周、10周深低温储存后，测定不同储存时限瓣膜生物力学指标。结果：各组瓣叶厚度、组织热皱缩温度及组织含水量随着组别呈逐渐递增趋势，但无统计学意义；破坏强度及伸长比差异有统计学意义。结论：深低温保存时限不同对瓣膜组织的生物力学均有不同程度的影响，尤其对瓣膜的破坏强度及伸长比影响最大，据此得出深低温保存随着时间延长，对瓣膜生物力学影响越大，此结果为临床心脏瓣膜储存最大时限提供理论依据。
Objective:We compared the effects of deep hypothermia preservation different time to cardiac valvular biomechanics. In order to promote the bioprosthetic valve preservation technology improvement.Methods:We prepared 5 groups of aortic valve, through the programmed cooling placed them in the deep low temperature liquid nitrogen(-196℃) storaged,after 2 weeks,4 weeks, 6 weeks,8 weeks,10 weeks deep cryogenic storage,we determined the valvular biomechanics indexes in different storage time. Results:The leaflet thickness,tissue shrinkage temperature and water content of tissues of each group showed a gradually increasing trend,but without statistical significance;breaking strength and elongation ratio have significant difference.Conclusion:Cryopreservation of different time limit of valvular tissue biomechanical influence in varying degrees,in particular,breaking strength and elongation ratio of valve are the largest effect,we derive the cryopreservation with the prolongation of t

[ 可能符合您检索需要的词汇 ]