晕厥患者的TCD表现及病因分析

目的：探讨晕厥患者的TCD表现并据此进行病因分析。方法：采用Dop P型经颅多普勒诊断仪对89例晕厥患者发作间歇期及61例健康体检者进行经颅多普勒检测。结果：病例组MCA、ACA、PCA、VA和BA的Vs、Vd、Vm均明显高于正常对照组（P〈0．05）,而各支脑动脉的PI值两组之间差别无统计学意义。结论：晕厥患者脑动脉血流速度常加快,脑血流动力学改变为晕厥的常见病因之一,建议晕厥患者常规行TCD检查。     

Evaluation of in-stent stenosis by magnetic resonance phase-velocity mapping in nickel-titanium stents

PURPOSE: To evaluate different grades of in-stent stenosis in a nickel-titanium stent with MRI. MATERIALS AND METHODS: Magnetic resonance phase velocity mapping (MR-PVM) was used to measure flow velocity through a 9-mm NiTi stent with three different degrees of stenosis in a phantom study. The tested stenotic geometries were 1) axisymmetric 75%, 2) axisymmetric 90%, and 3) asymmetric 50%. The MR-PVM data were subsequently compared with the velocities from computational fluid dynamic (CFD) simulations of identical conditions. RESULTS: Good quantitative agreement in velocity distribution for the 50% and 75% stenoses was observed. The agreement was poor for the 90% stenosis, most likely due to turbulence and the high-velocity gradients found in the small luminal area relative to the pixel resolution in our imaging settings. CONCLUSION: The accuracy of the MRI velocities inside the stented area renders MRI a modality that may be used to assess moderate to severe in-stent restenosis (ISR) in medium-sized vascular stents in peripheral vessels, such as the iliac, carotid, and femoral arteries. Advances in MR instrumentation may provide sufficient resolution to obtain adequate velocity information from smaller vessels, such as the coronary arteries, and allow MRI to substitute for invasive and expensive catheterization procedures currently in clinical use.     

麻醉诱导期罗库溴胺与阿曲库胺不同注射速度对血流动力学的影响

目的观察腹腔镜胆囊切除手术麻醉诱导期不同注射速度的罗库溴胺与阿曲库胺对血流动力学的影响。方法57例择期进行腹腔镜胆囊切除手术的患者随机分为R1、R2、A1、A2四组。监测并记录诱导前,肌松药注射后1、3min及手术结束时的平均动脉压（MBP）、心率（HR）,同时评估插管条件。结果A,组中,肌松药注射后1、3min的MBP比诱导前有明显下降,HR明显增快。其他各组MBP、HR未观察到明显变化。各组手术结束时的MBP、HR与诱导前比较,差异无统计学意义。结论麻醉诱导时快速注射罗库溴胺与阿曲库胺,阿曲库胺明显影响血流动力学。     

无临床神经症状糖尿病的神经电生理诊断价值

[目的]探讨神经电生理检查指标对无临床神经症状糖尿病（DM）患者的诊断价值。[方法]应用肌电图检测仪检测神经传导速度、经典的H反射和F波,对无临床神经症状DM组患组患者和正常对照组患者各30例进行横向和纵向的对比研究。[结果]DM组神经传导速度、H反射、F波较正常对照组均有显著性意义（P〈0.001）,H反射异常率为68%,感觉传导速度异常率高于运动神经传导速度,下肢神经传导速度异常率高于上肢神经传导速度。[结论]神经电生理是诊断DM早期周围神经病变的敏感及特异性的检查,其中最敏感的是H反射。     

多普勒超声检测房、室间隔缺损患者的肺、体循环血流量及分流量

运用多普勒超声(DE)技术检测13例房间隔缺损(ASD)和27例室间隔缺损(VSD)患者的肺循环血流量(Qp)、体循环血流量(Qs)及 Qp/Qs 比值和左向右分流量,并将数据与心导管 Fick 法作比较。结果显示,DE 检测的 Qp、Qs 及 Qp/Qs 比值均与 Fick 法结果呈高度正相关性,相关系数 r 分别为0.95、0.91和0.94(P 均<0.001)。DE 测定的 Qp 与 Fick 法测值无显著的统计学差异(P>0.5),Qs 则较 Fick 法者略高(0.010.5,>0.1,)并呈良好正相关性(r 分别为0.96、0.93,P<0.001)。作者认为,用 DE 检测 ASD 或 VSD 的 Qp、Qs 及 Qp/Qs 比值,以及由之计算的心内左向右分流量,方法可行,结果可靠;用 DE 直接测跨缺损处分流量,方法简便,初步结果可信,值得进一步研讨。     

定量组织速度及应变率显像对健康犬心肌运动特征的评价

目的探讨定量组织速度及应变率显像评价犬心肌运动的可行性及正常健康犬心肌各节段的运动特征。方法采集 18只健康杂种犬心肌各节段长轴TVI图像 ,分别对心肌定量组织多普勒速度及应变率曲线进行分析。结果健康犬心肌各节段定量组织速度曲线显示收缩期可见一正向波 (S波 ) ,舒张期可见两负向波 (E、A波 ) ,波峰清晰 ,紧邻S波及E波前分别可见等容收缩波及等容舒张波 ,从基底部到心尖部同一波峰时序基本一致 ,波幅依次递减 ;应变率曲线显示 :以上心动周期各波峰均清晰可见 ,但收缩期呈负向波 ,舒张期呈正向 ,从基底部到心尖部波幅基本一致。结论定量组织速度及应变率显像均能准确显示心肌各节段运动特征 ,但两者曲线意义不同。     

Assessment of Woodcrete Using Destructive and Non-Destructive Test Methods

Utilizing solid wastes and industrial by-products as a partial replacement for raw materials has become an acceptable practice among researchers and scientists in the civil engineering field. Sawdust and wood shavings are not an exception; they are being used in concrete as a partial or total replacement for some of its constituents. The main goal of this research is to establish a relation between destructive and non-destructive testing for concrete containing wood shavings as a partial replacement of sand (woodcrete). With this type of material existing, thus the need to understand the behavior of such material becomes urgent and evokes the need to ease the process of the assessment and the evaluation of such materials and therefore provide more understanding of its behavior. In addition to the conventional concrete mix, five mixes of woodcrete were made by replacing fine aggregate by volume with wood shavings at different replacement levels varied from 5% to 50%. Cubic samples were tested at the age of 90 days using nondestructive tests (NDT), namely, rebound hammer test and ultrasonic pulse velocity test. Then, the specimens were tested using a conventional compressive test using a universal compression testing machine. Statistical analysis was performed to establish empirical relations between destructive and non-destructive results. The dynamic modulus of elasticity was calculated, and some formulas to estimate the (compressive) strength of woodcrete using NDT results were proposed and tested against experimental results and showed acceptable results.     

定量组织速度成像技术评价冠心病心肌缺血及冠脉支架植入术疗效的研究

目的探讨定量组织速度成像（QTVI）技术在冠心病患者心肌缺血评价中的价值,同时采用QTVI技术观察冠状动脉（冠脉）支架植入术后左室局部心肌功能变化,以评价其疗效。方法 53例临床诊断冠心病或可疑冠心病行冠脉造影检查（CAG）的患者纳入本研究。在行CAG检查前作QTVI检查,根据节段室壁运动速度情况（以心底部5cm/s,中段3cm/s界定）分为无心肌缺血组（n=26）和心肌缺血组（n=27）。测定左室6个壁的基底段和中段运动的收缩期峰流速（Vs）与峰值位移（Ds）,比较2组的Vs及Ds,并与CAG结果对照,以评价QTVI对冠心病的诊断价值。其中8例单纯左前降支（LAD）病变患者分别于支架植入前1天、植入后1周、4周采用QTVI技术分析室壁的运动速度指标（Vs）,以评价支架植入术的疗效。结果在左室长轴切面、心尖四腔切面、心尖两腔切面心肌缺血组左室相应节段的Vs和Ds均低于无心肌缺血组（P〈0.05）;QTVI发现的有心肌缺血的27例患者,CAG均能发现2支或以上主要冠脉狭窄;8例LAD病变患者冠脉支架植入术前LAD供血区各节段心肌Vs均明显低于无心肌缺血组（P〈0.01或P〈0.05）,与冠脉支架植入前相比,治疗后1周及4周,LAD供血区各节段心肌Vs明显增快（P〈0.01或P〈0.05）。结论 QTVI技术通过定量测定节段性室壁运动失调及局域性心功能不良,可以评价冠心病严重冠脉狭窄患者的心肌缺血,且可作为一种测定冠脉支架植入前后局部心肌速度的无创技术,用以评价冠脉支架植入术的疗效。     

四种多普勒成像技术在冠状动脉狭窄与病变心肌检测中的价值

目的探讨左室局部心肌收缩和舒张速度、形变、位移及同步性变化与冠状动脉狭窄程度的关系。方法应用定量组织速度成像(QTVI)、应变率成像(SRI)、组织追踪(TT)和组织同步化成像(TSI)定量分析19例冠状动脉粥样硬化性心脏病(简称冠心病)患者和21名正常人左室局部心肌收缩期(Vs)、舒张早期(Ve)和舒张晚期峰值速度(Va);收缩末期(εsys)、峰值(εp)和收缩后应变(εps)及R波至峰值应变的时间(T-εp);收缩期(SRs)、等容舒张期(SRir)、舒张早期(SRe)及舒张晚期应变率(SRa);收缩期峰值位移(Ds)、R波至收缩期位移峰值的时间(T-ds)及收缩达峰时间(Ts)等指标。结果在中重度狭窄者中SRs(-0.79±0.69)s-1、SRir(-0.34±0.87)s-1、SRe(0.51±0.64)s-1及Vs(3.79±1.66)cm/s、Ve(-4.58±1.85)cm/s、Ds(7.84±2.94)cm/s较对照组SRs(-1.02±0.53)s-1、SRir(0.067±0.53)s-1、SRe(1.13±0.62)s-1及Vs(5.50±1.79)cm/s、Ve(-6.50±2.8...     

速度向量成像技术评价正常人左室舒张功能及其参考值范围

目的探讨应用速度向量成像技术(VVI)评价正常人的左室舒张功能并确定其正常参考值范围。方法结合超声、NT-BNP、临床症状等指标筛选健康人97名,使用西门子公司的Acuson Sequoia C512超声心动仪,采用VVI测量静息状态下左室二尖瓣环水平6个壁:室间隔、侧壁、前壁、下壁、前间隔、后壁的心肌舒张早期速度(E),脱机后进入VVI工作站操作界面采用盲法对图像进行VVI分析并计算平均值Em,测出E/Em,对正常人群的参考值范围给出参考界定。结果 97例正常人E/Em的参考值范围(单侧界限取95%界限)为(1,22.935);男性、女性E/Em参考值范围分别为(1,22.300)和(1,24.766);50岁以下男性、女性E/Em参考值范围分别为(1,22.413)和(1,24.314);50岁以上男性、女性E/Em参考值范围分别为(1,15.410)和(1,24.870)。结论 VVI作为一种新的超声技术,是无创性评价左室舒张功能的好方法,为临床准确评价左室舒张功能提供了一种可靠手段。