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本文旨在探讨高剂量瑞芬太尼对冠心病无痛胃镜检查患者循环系统及心肌损伤的影响。无痛胃镜检查的冠心病患者96例随机分为LR组(丙泊酚+瑞芬太尼0.2μg·kg^-1,n=48)和HR组(丙泊酚+瑞芬太尼0.5μg·kg^-1,n=48)。比较2组睫毛反射消失时间、胃镜检查时间、苏醒时间及丙泊酚用量,观察检查前(T 0)、检查开始即刻(T 1)、检查开始后5 min(T 2)、10 min(T 3)、检查结束即刻(T 4)SBP、HR、RPP及ST段、T波变化,并检测2组胃镜检查前和结束时cTnI、BNP等指标。结果显示,HR组睫毛反射消失时间、胃镜检查时间、丙泊酚用量低于LR组(P<0.05);T 3、T 4时HR组SBP、HR及RPP低于LR组(P<0.05);HR组T1、T2时ST段与T波改善情况优于LR组(P<0.05);HR组检查后cTnI、BNP水平低于LR组(P<0.05);HR组术中一般体动反应发生率低于LR组(P<0.05)。表明0.5μg·kg^-1瑞芬太尼复合丙泊酚用于冠心病无痛胃镜检查麻醉效果满意,对患者循环系统及cTnI、BNP的影响较小。 相似文献
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光学干涉测量具有非接触、高精度和全场测量的优点,能对形变、折射率、位移等信息进行测量。噪声滤除是光学干涉测量产生的条纹图像处理的一个关键问题。加窗傅里叶滤波(Windowed Fourier Filtering,WFF)与自适应加窗傅里叶滤波(Adaptive Windowed Fourier Filtering,AWFF)是有效的频域去噪算法。相干增强扩散(Coherence Enhancing Diffusion,CED)则是基于偏微分方程的空域去噪算法。针对条纹去噪问题,比较了WFF、AWFF和CED在不同密度和不同噪声类型的条纹图上的表现,分析了它们的适用条纹类型。 相似文献
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采用尿素水解法制备了Cu/SiO2催化剂, 探究其用于乙酸甲酯(MA)加氢制取乙醇的催化性能, 并通过N2物理吸附、X射线衍射(XRD)、程序升温还原(TPR)、透射电子显微镜(TEM)和X射线光电子能谱(XPS)等表征方法分析了催化剂的物理化学特性, 探究了铜负载量和还原温度等对催化剂结构的影响, 以及与催化活性之间的关系. 发现在铜负载量分别为10%、20%和30% (质量分数, w)的催化剂中, 铜负载量为20%的催化剂因具有较多且分散均匀的活性组分而表现出最佳的加氢效果. 接着在铜负载量为20%的催化剂上研究了还原温度(270, 350, 450 ℃)对催化性能的影响, 发现在350 ℃下还原的催化剂活性最高, 在最佳的反应条件下, 乙酸甲酯转化率达到97.8%, 乙醇选择性达到64.9% (理论最大值为66.6%), 主要归属于它具有较高的铜物种分散度, 最合适的Cu0/(Cu0+Cu+)摩尔比例, 同时实现了解离氢气和活化乙酸甲酯的功能. 相似文献
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Quantum state measurement in double quantum dots with a radio-frequency quantum point contact 下载免费PDF全文
We study the dynamics of two electron spins in coupled quantum dots (CQDs) monitored by a quantum point contact (QPC) detector. Their quantum state can be measured by embedding the QPC in an LC circuit. We derive the Bloch-type rate equations of the reduced density matrix for CQDs. Special attention is paid to the numerical results for the weak measurement condintion under a strong Coulomb interaction. It is shown that the evolution of QPC current always follows that of electron occupation in the right dot. In addition, we find that the output voltage of the circuit can reflect the evolution of QPC current when the circuit and QPC are approximately equal in frequency. In particular, the wave shape of the output voltage can be improved by adjusting the circuit resonance frequency and bandwidth. 相似文献
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Reinvestigation of the high spin states in ^(161)Er and enhanced E1 transitions in the N=93 isotones
High-spin states in 161Er have been studied experimentally using the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. The relatively enhanced E1 transitions between the 5/2+[642] and 3/2-[521] bands are observed in 161Er, and the B(E1) values are extracted experimentally. The systematics of the R(E1) values in the N=93 isotones are presented. It is found that the strength of the E1 transitions obviously exhibits angular momentum dependence, and the occurrence of the relatively enhanced E1 transitions could be attributed to octupole softness. 相似文献
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