Effect of propofol infusion on the endocrine response to cardiac surgery

PURPOSE: Bilateral lower extremity venous duplex scanning for acute deep venous thrombosis (DVT) has been advocated because of the high incidence of occult contralateral leg involvement. We investigated the clinical necessity of such a policy. METHODS: The results from 2996 venous duplex studies performed during the past 2 years were retrospectively reviewed. A total of 1694 of these scans were performed on patients with symptoms, of whom 248 (15%) were found to have an acute DVT. Symptoms were limited to one side in 198 patients, whereas bilateral complaints were noted in 50 patients. RESULTS: Among the patients with symptoms of acute DVT, 72 (29%) had bilateral involvement. Bilaterality was more likely in patients with bilateral symptoms than in those with only unilateral symptoms (56% vs 22%; p < 0.005). Of the patients with unilateral symptoms and bilateral DVT, all of them had either acute (80%) or acute and chronic (20%) thrombosis in the symptomatic leg. The contralateral asymptomatic limb had fewer acute and more chronic DVT (41% and 55%, respectively). No patient from the entire group admitted with symptoms had an acute DVT in the asymptomatic limb without a concomitant acute DVT in the symptomatic leg. Unilateral scanning would decrease the examination time by 21% and potentially increase total reimbursement for symptomatic venous scans by 9% compared with routine bilateral duplex scanning. CONCLUSIONS: Although bilateral involvement is frequent in patients with symptoms of acute DVT, treatment in these patients is not altered by this finding. We conclude that contralateral venous scanning in patients with unilateral symptoms is not clinically indicated and that unilateral scanning would result in improved cost-efficiency for vascular laboratories.     

基于IPC的开放式工业机器人控制系统研究

开放性是现代机器人控制系统的实现目标之一。开放式工业机器人控制系统采用基于工业计算机（IPC）结合运动控制卡的结构形式,并借鉴ORC（Open Robot Controller）等典型的机器人控制系统软件体系结构设计了分层模块化的软件系统,使得现有的机器人控制系统只需要做少量的修改就能应用到不同的场合。     

AutoCAD创建机械制图样板文件

介绍了用AutoCAD绘制机械图样时涉及到的《技术制图》和《机械制图》国家标准,给出了AutoCAD各部分绘图参数的设置和样板文件创建的方法.     

基于PSO和LSSVM温度控制器的设计

利用离子群优化（PSO）算法的全局搜索功能和最小二乘支持向量机（LSSVM）泛化能力强、运算速度快的特点,设计了一种温度控制器。通过LSSVM 对输入输出数据的训练学习,建立其预测模型;然后运用粒子群算法完成控制过程的滚动优化。该方法克服了PID控制中存在的控制精度不高、抗干扰能力差以及实时性不好的缺点。通过对连续槽式搅拌反应器（CSTR）温度控制的实际应用,证明了该方法的有效性。     

科技期刊评价指标的有关争议的探析

分析了当前科技期刊评价及科技成果评价中一些的现象,认为科技期刊应该在评价中正确对待SCI收录指标,充分利用其有利方面,避免其局限性所形成的误区,这对我国科技期刊评价体系的建立,具有重要的现实意义。     

基于OPEN3000系统的低周减载实时控制方法

由于传统的低周减载装置无法进行实时调整,为确保电网安全运行的第三道防线得到100%落实,减轻人工操作量,降低误操作的可能性,提出了基于OPEN3000系统的低周减载实时控制方法。该方法具有动态优化和实时控制两大功能,能根据OPEN3000中相关线路的潮流数据进行优化配置,并利用遥控功能实现对相关低周减载功能的实时投退,在确保第三道防线安全可靠的同时,减轻相关人员的工作量,提高电网的安全运行水平。     

基于多变量概率模型的钻井周期预测方法

鉴于现有的预测钻井周期的方法忽视了影响钻井周期的关键因素因而精确度有限,提出采用多变量概率法预测钻井周期,并采用实测数据进行了算例分析和验证.利用自适应核密度估计法建立了各主要钻井阶段与深度相关的钻井周期概率模型,结合蒙特卡洛模拟得出了一次完整钻井施工作业的总周期的概率分布.采用该方法对澳大利亚及亚洲地区192 口井的...     

混凝土空心砌块保温性能测试方法研究

混凝土空心砌块砌体的保温性能是建筑节能工程设计时的关键指标,可用热阻或传热系数来反映。采用直接法和间接法两种测试方法均可得到混凝土砌块及其砌体的保温性能,但间接法在开发新产品、设计新的建筑结构形式时具有显著的优点。     

Office technology and musculoskeletal disorders: building an ecological model

Symptoms drive health care utilization. Therefore, health care costs are reduced by reducing musculoskeletal injuries through job redesign, ergonomics, or changes in work scheduling.     

经PS加固土遗址水饱和强度及加固效果的环境影响研究

 以新疆交河故城遗址土做试样,首先用不同浓度的PS加固,经过一段时间干燥后得到不同初始含水率的试样,然后进行渗透系数测试,之后再进行不固结不排水试验,测量试样的抗剪强度。同时,进行PS加固试样的水稳定变化测试(即水中崩解试验),耐风蚀的风洞模拟试验,冻融破坏对加固强度的影响、温差破坏对力学强度影响及干湿破坏对力学强度影响等试验,研究古丝绸之路特殊环境因素对PS加固土遗址保护效果的影响。结果显示,PS加固对土的饱和渗透系数影响很小,而被3%和7%PS加固后的试样峰值抗剪强度比加固前的分别提高了90%和360%,残余抗剪强度也分别提高了50%和250%。结果说明,PS加固后土遗址仍具有很好的渗透性,但被雨水渗透饱和后,仍具有很明显的加固强度。这就证明PS适用于丝绸之路干旱区古代土遗址的加固保护。