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21.
Kang CHEN Ye MAO Shao-hua LIU Qiong WU Qing-zhi LUO Wen-qi PAN Qi JIN Ning ZHANG Tian-you LING Ying CHEN Gang GU Wei-feng SHEN Li-qun WU 《Journal of Zhejiang University. Science. B》2014,15(6):507-514
Objective
We are aimed to investigate whether right ventricular mid-septal pacing (RVMSP) is superior to conventional right ventricular apical pacing (RVAP) in improving clinical functional capacity and left ventricular ejection fraction (LVEF) for patients with high-degree atrio-ventricular block and moderately depressed left ventricle (LV) function.Methods
Ninety-two patients with high-degree atrio-ventricular block and moderately reduced LVEF (ranging from 35% to 50%) were randomly allocated to RVMSP (n=45) and RVAP (n=47). New York Heart Association (NYHA) functional class, echocardiographic LVEF, and distance during a 6-min walk test (6MWT) were determined at 18 months after pacemaker implantation. Serum levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured using an enzyme-linked immunosorbent assay (ELISA) kit.Results
Compared with baseline, NYHA functional class remained unchanged at 18 months, distance during 6MWT (485 m vs. 517 m) and LVEF (36.7% vs. 41.8%) were increased, but BNP levels were reduced (2352 pg/ml vs. 710 pg/ml) in the RVMSP group compared with those in the RVAP group, especially in patients with LVEF 35%–40% (for all comparisons, P<0.05). However, clinical function capacity and LV function measurements were not significantly changed in patients with RVAP, despite the pacing measurements being similar in both groups, such as R-wave amplitude and capture threshold.Conclusions
RVMSP provides a better clinical utility, compared with RVAP, in patients with high-degree atrioventricular block and moderately depressed LV function whose LVEF levels ranged from 35% to 40%. 相似文献22.
Abstract:The dynamism of contemporary Chinese society reflects itself in higher education and the academic profession. The remarkable changes in the past 30 years include the shifting from a planned system to a market system on one hand, and the shifting from a closed system to an open system on the other hand. Five obvious transformations in higher education resulted from this social dynamism. They are identified as massification, decentralization, marketization, differentiation, and internationalization respectively. Such a dynamic context has complicated the scenario for the Chinese academic profession. 相似文献
23.
陈懋 《福建工程学院学报》2015,(3):235-238
分析现有第三代移动通信系统TD SCDMA的室内分布存在的容量、覆盖和质量的问题,给出针对现有问题的改善方法。并通过具体案例进一步说明室内分布系统的设计思路和优化方法,实际测试的结果验证了该方案在改善TD SCDMA室内分布系统性能上的正确性和可行性。 相似文献
24.
毛少宏 《黎明职业大学学报》2005,(3):57-60
针对地方高校技术物资采购工作中普遍存在的问题,结合技术物资管理工作实践,探讨了地方高校技术物资采购的运作模式,其内容包括构建新型的物资采购管理体制,建立健全物资采购规章制度体系,规范招标采购运作方式,加强采购全过程的监督机制。 相似文献
25.
毛龙灿 《咸阳师范学院学报》2001,16(5):47-48
本通过对部分学生对《形势与政策》课教学所持的消极态度的调查,分析了产生这些态度的基本原因,提出了解决这些问题的建议。 相似文献
26.
文章根据现代工程教育理念,分析了当前机械类专业教学中存在的主要问题及形成的原因,提出了以创新能力培养为导向的机械类专业实践课程改革与研究的思路、总体目标和改革的主要内容,以组织学生参加全国大学生机械创新设计大赛为例总结了已取得的经验。 相似文献
27.
Atsushi Sugiura Toshihiro Kitama Masahiro Toyoura Xiaoyang Mao 《Anatomical sciences education》2019,12(5):561-571
Human anatomical specimen museums are commonly used by medical, nursing, and paramedical students. Through dissection and prosection, the specimens housed in these museums allow students to appreciate the complex relationships of organs and structures in more detail than textbooks could provide. However, it may be difficult for students, particularly novices, to identify the various parts of these anatomical structures without additional explanations from a docent or supplemental illustrations. Recently, augmented reality (AR) has been used in many museum exhibits to display virtual objects in videos captured from the real world. This technology can significantly enhance the learning experience. In this study, three AR-based support systems for tours in medical specimen museums were developed, and their usability and effectiveness for learning were examined. The first system was constructed using an AR marker. This system could display virtual label information for specimens by capturing AR markers using a tablet camera. Individual AR markers were required for all specimens, but their presence in and on the prosected specimens could also be obtrusive. The second system was developed to set the specimen image itself as an image marker, as most specimens were displayed in cross section. Visitors could then obtain the label information presented by AR without any markers intruding on the display or anatomical specimens. The third system was comprised of a head-mounted display combined with a natural click interface. The system could provide visitors with an environment for the natural manipulation of virtual objects with future scalability. 相似文献
28.
有利于产业创新升级的企业成长模式一直是研究热点问题。本文将我国产业创新升级普遍存在的低产业化、大而不强和传统产业升级抽象为企业规模阈值问题,并通过对三种规模阈值的突破引入和界定了企业规模质量的概念范畴。以此为基础并结合文献分析法,本文提出构成企业规模质量的R&D投入、非R&D投入和知识能量3个维度及11个能力要素,通过预测试、问卷调查等方式进一步实证检验了量表的可靠性和有效性,得出了有助于推动产业创新升级的企业规模质量量表工具。在量表工具下本文提出了针对技术创新和产业升级的对策建议。 相似文献
29.
In this paper, we consider global adaptive feedback control of nonlinear systems with unknown parameters entering nonlinearly. Such unknown parameters are also not required to lie in a known compact set. Unlike previous results, our proposed adaptive controller is a new double dynamical switching-type controller in which the controller parameter is tuned in a flexible switching manner via a monotonically decreasing switching logic and the controller combines the traditional adaptive theorem with the switching scheme perfectly. Global stability results of the closed-loop system have been proved. 相似文献
30.
近年,ERP(Enterprise Resource Planning、企业资源计划)系统已在企业中大量实施,它已显著提高了企业内部信息传递效率并为企业各级管理层的决策提供了大量及时、准确的信息。由于目前的企业中实施的ERP系统大都是一些软件公司的标准产品,十分适用于采购、制造、销售、仓管、财务等标准流程。但对于企业的一些特殊流程却无法完全适应。企业的IT部门会自行开发或委托外部企业专门针对自己的一些特性需求做一些二次开发,使企业内部的流程更优化、效率更高。 相似文献