Unsteady Fluid Dynamics of Several Mechanical Prosthetic Heart Valves Using a Two Component Laser Doppler Anemometer System

Abstract: Five typical mechanical heart valves (Starr-Edwards, Björk-Shiley convexo-concave (c-c), Björk-Shiley monostrut, Bicer-Val, and St. Jude Medical) were tested in the mitral position under the pulsatile flow condition. The test program included measurements of velocity and turbulent stresses at 5 downstream locations. The study was carried out using a sophisticated cardiac simulator in conjunction with a highly sensitive 2 component laser Doppler anemometer (LDA) system. The continuous monitoring of parametric time histories revealed useful details about the complex flow and helped to establish the locations and times of the peak parameter values. Based upon the nondimensional presentation of data, the following general conclusions can be made. First, all the 5 valve designs created elevated turbulent stresses during the accelerating and peak flow phases, presenting the possibility of thromboembolism and perhaps hemolysis. Second, the difference in valve configuration seemed to affect the flow characteristics; third, the bileaflet design of the St. Jude valve appeared to create a lower turbulence stress level.     

上海市闵行区流动人口中的孕产妇保健状况

通过对上海市闵行区580名外来孕产妇及580名作为对照的本地孕产妇的孕产期保健现况调查分析,表明外来孕产妇缺乏必要的孕产期保健措施,有47.6％的外来孕产妇从未做产前检查,产后保健则完全没有,并由此而造成外来产妇在急产、死产、甚至孕产妇死亡等方面令人忧虑的现状。为适应和促进当前经济发展的新形势,改善流动人口的孕产妇保健状况,应对流动人口中孕产妇保健状况深入研究,并采取相应的措施。     

试析医学生创新素质的文化内涵

21世纪医学人才的重要特征之一即创新素质。创新素质不是空洞的、抽象的，而是具体的、实在的。因此，从多疑多思的批判精神，阐幽发微的探索激情，滴水穿石的攻关热忱，勇于进取的开拓意识，兢兢业业的奉献态度，高超娴熟的业务能力和识取信息的超常才能7个方面阐述了医学生创新素质的文化内涵。     

BENEFICENCE,TEMPERANCE AND MEDICAL SCIENCE

John Coakley Lettsom (1744–1815) founded the Medical Society of London and played a key role in the development of the Royal Humane Society. His Quaker background underpinned his interest in social reform. He established dispensaries and soup kitchens for the poor, recognized the need for public health measures in the control of disease, and advocated prison reform and education of the poor.     

心血管疾病基因治疗的基础研究Ⅵ．一种新的体内基因转移方法

将医用缝合线浸泡在质粒ＤＮＡ溶液中，然后缝合在大鼠股四头肌上，可以观察到外源基因在肌肉组织中高效、稳定地表达，其表达量高于磷酸钙共沉淀和ＤＮＡ沉淀块埋植法，较肌肉直接注射法表达量高１０倍左右。     

军队高等医学院校课程教学质量评估的功能及意义

军队高等医学院校课程教学质量评估的意义及作用:具有判断教育活动、获取信息、反馈、激励、促进教学改革六项功能.     

历史传承与现代追寻——论医学院校校园文化的生成与构建

本文从校园文化的内涵与外延入手，就如何构建医学院校校园文化进行了探索。     

妇幼保健院医疗设备配置的思考和探讨

妇幼保健院运营的模式,服务的对象都有别于综合性医院。通过对设备使用效益的调查、分析,提出妇幼保健院医疗设备的配置,应符合本院的特点。配置应遵循:适用性、特色性、经济性、先进性,不可盲目求新、求全,避免设备使用的低效益。     

老年人高粘滞血症预防的初步探讨

本文报告对32例60岁以上健康老年人预防高粘滞血症的观察结果.经采取综合预防措施六年,血流变学检测表明:全血(比)粘度、血浆(比)粘度、血沉、红细胞压积均低于对照组,统计学处理表明,前三项指标P值均小于0.01,因此达到了对老年人高粘滞血症的预防目的.     

医学生素质教育中几对关系的处理

当医学素质教育中广博、个性、创新等观念日益被教育者和教育对象接受的同时，常常又容易陷入另一个误区，即盲目接纳、肯定这些观念，高没有对其进行审慎、辩证的思考，文章通过素质教育中几对观念的辨析，以期对此形成客观、全面的认识。