Off-pump coronary artery bypass grafting versus on-pumpcoronary artery bypass grafting: which is better in patients with chronic obstructive pulmonary disease?

INTRODUCTION Conventional coronary artery bypass graftin(CCABG) with cardiopulmonary bypass (CPB) habeen accepted as an effective and safe treatment fomulti-vessel coronary heat disease. CPB may stilcontribute to the operation field because of threlatively easier technical requirement; but it alscauses a serious systematic inflammatory reactiowhich will lead to dysfunction of important organand higher cost for the patients. Off-pump coronarartery bypass grafting (OPCABG) has r…     

大高宽比空冷汽轮发电机定子线棒制造工艺研究

根据大型空冷汽轮发电机的结构特点,重点研究了定子线圈的制造工艺,并就一些关键工序所采取的新工艺和新工具与水冷定子线圈进行了对比,,进而形成了一套完整的空冷定子线圈制造体系。     

二尖瓣病变合并冠心病13例外科治疗体会

目的总结二尖瓣病变合并冠心病的外科治疗体会。方法对13例二尖瓣病变合并冠心病患者同期行二尖瓣置换或成型及冠脉搭桥术,回顾性分析,临床资料。结果术后1例死于严重心律失常,其余均存活。随访3—36个月,心功能恢复至Ⅰ-Ⅱ级9例,Ⅲ级3例,未出现心肌缺血症状。结论术前明确诊断,充分准备,术中加强心肌保护,提高手术水平,缩短手术时间,加强围手术期治疗是手术成功的关键。     

介绍一种水轮机调速器残压测频信号预处理电路

在水轮机调速器系统中残压测频是主要环节，其测频的稳定性和精度直接反映调速器能否快速响应，并稳定运行。高次谐波的引入是造成调速器残压测频不稳定的主要原因，因此需要设计一个新的残压测频电路，彻底消除高次谐波的影响。     

基于Fiddler代理程序的电子资源使用统计分析系统的设计与应用

[目的/意义]对比分析国内图书馆自行采集电子资源使用统计数据的主要方法,解决现有技术方法无法采集基于HTTPS协议的电子资源访问信息的问题。[方法/过程]在现有基于旁路监听的采集模式的基础上对技术加以改进,通过策略路由和Fiddler代理程序来实现基于HTTPS协议访问的电子资源使用数据的统计和分析,并在此基础上设计并应用电子资源使用统计分析系统。[结果/结论]解决了基于HTTPS协议访问的电子资源使用数据的采集问题,对其他图书馆自行采集电子资源使用统计数据有一定的借鉴作用。     

135MW机组汽轮机注油试验出现的故障分析与处理

通过对一台135MW的汽轮机在注油试验中出现的故障分析与处理,阐述了汽轮机在做注油试验过程中出现故障的分析及处理方法。     

Evaluation of orthotopic liver transplantation with no veno-venous bypass

Objective: To assess the feasibility and outcome of orthotopic liver transplantation (OLT) with no veno-venous bypass(v-v bypass) in adult patients. Methods: Between 1999 and 2001, 43 adult patients underwent OLT with v-v bypass, 33 with no v-v bypass. The operation time, anhepatic time, amount of blood loss, amount of blood transfusion, ICU stay days of the two groups were compared; renal function and gastrointestinal function in the two groups were examined. Results: There was no significant difference in mean serum creatinine on day 3 and gas discharge time in patients with v-v bypass or not. With no v-v bypass, the average operation time was 5.7±1.3 hours, anhepatic time was 64±13 minutes, median amount of blood loss in operation was 4000±820 mL, median amount of blood transfused intraoperatively was 4650±910 mL, median ICU stay was 5.7 days; all those were lower or shorter than those with v-v bypass; and these differences between the two groups had statistical significances. Conclusion: OLT with no v-v bypass is safe and can be performed in the majority of adult patients. The practice of liver transplantation with no v-v bypass is associated with shorter total operation time, shorter anhepatic time, lower blood product usage, and shorter ICU stay compared with standard technique of OLT with routine use of v-v bypass. Project supported by Zhejiang Provincial Health Bureau (No.2000/ZD003)     

基于光纤传感的小型风力机轴向推力测量研究

获得小型风力机轴向推力的方法通常有两种。一种是理论计算,其准确性不高,必须要进行修正;另一种是接触式的应变片传感测量,灵敏度不高,精度较低。本文提出一种非接触式光纤传感测量方法,实验表明该方法灵敏度比应变片式传感测量提高十倍以上,测量精度达到0.5%,可推广应用于转轴式的轴向推力测量。     

Arterial blood gas management during cardiopulmonary bypass

This study sought to investigate the effects of α-stat and pH stat regimens on cardiac outcome during moderate hypothermic cardiopulmonary bypass. 100 patients undergoing elective coronary artery bypass grafting (CABG) were randomly assigned with respect to the target value for PaCO₂ during cardiopulmonary bypass (CPB) into 2 groups. In 50 patients the target PaCO₂ was 40 mmHg, measured at a standard electrode temperature of 37°C while in the other 50 patients the target PaCO₂ was 40 mmHg, corrected to the patients nasopharyngeal temperature (lowest value reached: 32±0.5°C). There were no significant differences between groups with regards to cardiac outcome such as appearance of new ‘Q’ waves on the electrocardiogram, postoperative creatinine kinase-MB fraction, systemic vascular resistance (SVR), cardiac index (Cl), need for inotropic or intra-aortic balloon pump support and the length of postoperative ventilation or intensive care unit stay. These findings support the hypothesis that CO₂ management during CPB at moderate hypothermia has no clinically significant effect on cardiac outcome.     

可倾瓦滑动轴承轴瓦变形数值分析

本文基于ansys有限元分析软件,对三种可倾瓦滑动轴承进行流固耦合分析,得出了油膜压力分布、轴瓦应力分布和轴瓦变形三者之间的关系：油膜压力分布决定了轴瓦的应力分布,从而影响了轴瓦形变分布。通过对比发现,三瓦可倾瓦滑动轴承和四瓦可倾瓦滑动轴承的油膜承载能力相当,而四瓦可倾瓦滑动轴承轴瓦应力分布较均匀,并且轴瓦形变量在汽轮机轴承正常运行许应形变内,所以四瓦可倾瓦滑动轴承更适用于汽轮机这样的重载高速旋转机械。