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1.
目的探讨超声二维斑点追踪成像(two-dimensional speckle tracking imaging,2D-STI)评价原发性高血压患者左室扭转(left ventricular twist,LVtw)重构特征的应用价值。 方法25例原发性3级高血压患者与30例正常成人经胸采集标准动态左室基底部及心尖部的胸骨旁短轴二维图像并存贮。在Echo PAC超声工作站上获取各层面在收缩期和舒张期左室的旋转角度和旋转率度曲线。LVtw(率)值定义为左室心尖部与基底部2个层面旋转角度(速度)的差值。为消除不同个体间心率差异,对时间参数进行标化。 结果原发性3级高血压患者与正常人的左室旋转和解旋曲线的走行趋势基本一致。扭转曲线图:收缩期左室呈短暂的逆时针扭转后,心底水平迅速呈顺时针旋转,同时心尖水平呈逆时针旋转,2个水平的旋转角度均于收缩期末达峰值。左室扭转角度均在(97±10)%(收缩末期)达到峰值。至舒张期,心室则表现为快速反向的解旋运动;与正常组相比,原发性3级高血压患者的左室峰值扭转度明显增大(P〈0.001),左室峰值扭转速度及达左室峰值扭转速度时间测值则无明显差异(P〉0.05);左室舒张期解旋率显著减小(P〈0.001),解旋速度达峰时间延长(P〈0.05),解旋峰值速度增大(P〈0.05)。 结论超声二维斑点追踪技术可全程量化左室扭转重构,并从机械力学角度对左室心肌功能进行合理解释,为临床防治原发性高血压提供理论依据。  相似文献   

2.
目的 应用斑点追踪技术(STI)评价高血压合并左室肥厚(LVH)患者左室的扭转及解旋运动.方法 采集29例正常人和50例原发性高血压伴轻度左室肥厚(LVH)及中-重度LVH患者左室短轴心尖和心底水平二维图像,用EchoPAC工作站脱机分析.计算扭转角度峰值(Ptw)、收缩末期扭转角度(AVCtw)、等容舒张末期扭转角度(MVOtw)、解旋率(UntwR)、扭转速度峰值(PTV)、扭转速度达峰时间(TPTV)、解旋速度峰值(PUV)和解旋速度达峰时间(TPUV).结果 高血压轻度LVH及中-重度LVH组Ptw、AVCtw、MVOtw较正常组明显增加(P<0.05).UntwR在三组间两两比较,差异均有显著性(P<0.05).与正常组及轻度LVH组比较,中-重度LVH组TPUV明显延长(P<0.05).结论 STI技术可准确评价高血压LVH引起的左室功能的改变;UntwR可能成为一个评价左室舒张功能的新指标.  相似文献   

3.
目的 探讨应用超声斑点追踪成像技术(STI)评价心尖肥厚型心肌病(AHCM)患者左心室扭转运动(LVtor)的临床应用价值.方法 对34例AHCM患者与21名健康志愿者行二维超声检查.获取左心室短轴二尖瓣环水平、心尖水平二维图像,应用STI软件测定左心室短轴心底水平、心尖水平心肌旋转角度峰值及达峰时间、旋转速度峰值;测定左心室整体扭转角度峰值(Ptw)、达峰时间、左心室舒张期解旋减半时间(HTU);计算舒张期解旋率(Untw R);比较两组间各参数差异.HTU分别与二尖瓣口舒张早期峰值(E)、舒张晚期峰值(A)及E/A值行相关分析.结果 AHCM组左心室短轴心尖水平心肌收缩期旋转角度峰值和旋转速度峰值均较对照组增加,达峰时间延长(P均<0.05);AHCM组左心室整体Ptw及扭转速度峰值较对照组显著增大(P均<0.05);AHCM组舒张期HTU较对照组延迟,Untw R降低,解旋速度峰值减低(P均<0.05).AHCM组HTU与E/A值呈负相关.结论 AHCM患者在左心室收缩功能正常时,心尖部旋转及左心室扭转运动增强,Untw R降低.STI可敏感地反映出AHCM患者的心肌功能变化.  相似文献   

4.
目的使用斑点追踪显像(speckle tracking imaging,STI)技术评价正常成人左室扭转和解旋运动,并探讨年龄对其运动的影响。 方法记录76例健康成人的左室基底部和心尖部短轴高帧频二次谐波图像,应用二维应变分析软件分别获得2个平面的旋转角度-时间和旋转速度-时间曲线,根据其平均值绘制左室整体的扭转角度-时间和扭转速度-时间曲线,测量扭转峰值、等容舒张末期扭转角度、扭转速度峰值及达峰时间,计算解旋率。 结果收缩期左室产生扭转运动,包括基底部顺时针旋转和心尖部逆时针旋转,收缩末后立即发生快速解旋运动。老年组的扭转峰值、等容舒张末期扭转角度明显大于中年组(P〈0.001)和青年组(P〈0.001),老年组(P〈0.05)及中年组(P〈0.05)的解旋率明显低于青年组,扭转速度负向达峰时间也延迟(P〈0.05)。 结论二维斑点追踪技术可以无创评价左室扭转和解旋运动,年龄是其影响因素。  相似文献   

5.
目的 应用斑点追踪技术(STI)评价急件前壁心肌梗死(AMI)患者左心室扭转及解旋运动的变化.方法 38例AMI患者根据左室射血分数(LVEF)分为两组:LVEF正常组(LVEF≥45%,21例)和LVEF减低组(LVEF<45%,17例).20例正常人作为对照组.取左室心尖和心底短轴二维图像,应用EchoPAC超声工作站进行脱机分析,计算左室扭转角度峰值(Ptw)、收缩末期扭转角度(AVCtw)、等容舒张末期扭转角度(MVOtw)、解旋率(UntwR)、扭转速度峰值(PTV)、扭转速度达峰时间(TPTV)、解旋速度峰值(PUV)和解旋速度达峰时间(TPUV).结果 与对照组及LVEF正常组相比,LVEF减低组Ptw、AVCtw、MVOtw、UntwR明显减低,差异均有统计学意义(P<0.05).三组之间PUV、PTV及TPTV差异无统计学意义(P>0.05).UntwR与LVEF及左室收缩末期容积有相关性.结论 STI技术可准确评价前壁AMI患者左室扭转及解旋.AMI患者LVEF减低组左室扭转角度及UntwR明显减低;左室扭转及解旋影响左窒收缩功能.  相似文献   

6.
目的 运用超声斑点追踪显像技术(STI)评价健康人左室心肌节段和整体扭转运动特征.方法 运用STI技术对35例正常人左室心尖、乳头肌和心底水平整体和节段旋转角度进行测量,计算并记录左窒整体及节段扭转角度峰值(peak-tw)和达峰时间(time to peak-tw),从而定量分析心动周期中左室整体和节段扭转特征.结果 正常人心室扭转特征为:收缩期,心尖部呈逆时针方向旋转,心底部呈顺时针方向旋转,心室逆时针方向扭转;舒张期,心室反向解旋;心肌各节段室壁对整体扭转贡献由心尖至心底递减.结论 斑点跟踪显像技术可以无创性地评估左室整体及节段心肌扭转,具有良好重复性,为临床评价左室心功能提供一种敏感而可靠的新方法.  相似文献   

7.
目的 采用超声二维斑点追踪显像技术(STI)探讨肥厚型心肌病(HCM)患者左室扭转运动的特征.方法 随机选取心功能测值正常的HCM患者及正常对照各35例,取胸骨旁左室心尖和心底短轴观二维图像对左室旋转及径向位移进行测量分析,记录并计算心底部旋转角度峰值(Prot-MV)、心尖部旋转角度峰值(Prot-AP)、扭转角度峰值(Ptw)、收缩期末扭转角度(AVCtw))、等容舒张期末扭转角度(MVOtw)、解旋率(Untw R)、解旋减半时间(HTU)、收缩期末径向位移(AVCdisp)、等容舒张期径向位移(IVRTdisp),比较两组间上述各参数的差别;同时构建左室扭转一径向位移环,并分析其各形态参数.结果 ①与对照组比较.HCM组Prot-MV、Prot-AP、Ptw、AVCtw、MVOtw、HTU测值均增加,Untw R测值减低,两组间差异均有统计学意义(P均<0.05),而AVCdisp、IVRTdisp测值差异无统计学意义.②HCM组内左室旋转心尖部达峰时间较心底部测值增加,差异有统计学意义(P<0.05).③与对照组比较,HCM组收缩期及等容舒张期左室扭转-径向位移环的变化斜率均增加,差异均有统计学意义(P均<0.05).结论 STI显示HCM患者左室旋转运动力学参数较正常人有明显异常改变.  相似文献   

8.
目的 应用速度向量显像技术研究正常人和肥厚型心肌病(HCM)患者的左心室心肌扭转方式.方法 对25例健康志愿者(对照组)和41例HCM患者(HCM组)行常规超声心动图检查,采集二尖瓣水平短轴观、心尖水平短轴观、心尖四腔观及心尖二腔观二维图像,得到左室舒张末期容积、收缩末期容积、左室射血分数和室壁厚度.脱机分析得到收缩期心底部心内膜、心外膜和心尖部心内膜、心外膜的扭转速度峰值及扭转位移峰值,并分别计算心底部内外膜扭转速度/位移差值及心尖部内外膜扭转速度/位移差值.结果 收缩期心室扭转在心底部呈顺时针,在心尖部则呈逆时针,心尖部扭转幅度显著大于心底部(P<0.05或P<0.001),心内膜扭转显著大于心外膜(P<0.01或P<0.001).扭转速度-时间曲线由一个收缩期峰和两个舒张期峰组成,扭转位移- 时间曲线由一个舒张末期的小峰和一个收缩期的大峰组成.HCM组心底部呈不对称性肥厚,在显著肥厚的节段,HCM组心肌内外膜扭转速度/位移差值显著大于对照组(P<0.01或P<0.001).结论 速度向量显像技术能够简便准确地评价心室扭转,并能够发现HCM患者内外膜心肌扭转的不协调性.  相似文献   

9.
目的 应用斑点追踪显像(speckle tracking imaging,STI)技术评价右心室不同部位起搏后左心室扭转变化,揭示心室激动顺序异常时左室心肌扭转的变化.方法 选择11例右室心尖(right ventricular apex,RVA)起搏患者,11例右室流出道(right ventricular outflow tract,RVOT)起搏患者及13例正常志愿者,应用STI技术对其胸骨旁左室心尖和基底段短轴的二维图像分析左室心肌的旋转.结果 ①起搏组的扭转曲线普遍较正常对照组降低、顿挫,RVA起搏组(12.57°±4.19°)、RVOT起搏组(12.43°±5.46°)的扭转角度峰值均小于正常对照组(18.98°±5.73°),差异有统计学意义(均P<0.01),而两起搏组间比较差异无统计学意义(P>0.05),扭转角度达峰时问在三组间两两比较差异无统计学意义(P>0.05).②心尖段扭转角度在正常对照组、RVA起搏组及RVOT起搏组中呈现递减趋势,但仅RVOT起搏组与正常对照组问差异有统计学意义(7.40°±4.27°对12.70°±6.82°,P=0.0364).③基底段扭转角度达峰时间标准差(Tp-SD)比较,RVOT起搏组显著大于正常对照组(14.1%对4.87%,P=0.0298);而整体Tp-SD比较,RVA起搏组显著大于正常对照组[(7.6±6.5)%对2.26(1.62~3.51)%,P=0.0423].④与正常对照组相比,起搏组的扭转速度曲线较杂乱无序,但三组间两两比较扭转速度峰值、解旋速度峰值、扭转速度达峰时间、解旋速度达峰时间差异均无统计学意义.结论 起搏器植入后心肌节段扭转同步性降低,左室整体扭转受到抑制,可能影响左室收缩功能和舒张功能.  相似文献   

10.
目的应用超声二维斑点追踪显像技术探讨不同年龄正常成人左室扭转运动特征。方法健康成年志愿者121例,按年龄分为青年组(18~45岁)、中年组(46~64岁)和老年组(≥65岁)。取胸骨旁左室心尖和心底短轴观对左室旋转进行测量分析,计算出扭转角度峰值(Ptw)、收缩末期扭转角度(AVCtw)、等容舒张末期扭转角度(MVOtw)、解旋率(UntwR)、解旋减半时间(HTU)、扭转速度峰值(PTV)、扭转速度达峰时间(TPTV)、解旋速度峰值(PUV)和解旋速度达峰时间(TPuV),比较不同年龄组的差别。结果正常人左室扭转运动主要表现为心底部顺时针旋转和心尖部逆时针旋转,心脏整体表现为心动周期内逆时针方向为主的扭转运动。扭转速度参数的方向在收缩期主要表现为逆时针方向扭转;舒张期则表现为顺时针方向扭转。扭转角度于收缩末期达峰值。随年龄增加,Ptw、AVCtw、MVOtw、HTU和PuV测值逐渐增加,UntwR测值逐渐减低,三组间比较差异均有统计学意义(P〈0.05)。而TPuV、PTV、TPTV测值三组间比较差异均无统计学意义(P〉O.05)。结论应用超声二维斑点追踪显像技术可无创性评价正常人左室扭转运动特征。临床在应用扭转评价左室功能时,应充分考虑年龄因素的影响。  相似文献   

11.
Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.  相似文献   

12.
Three supplementary perspectives are presented arguing that interprofessional collaboration is both necessary and desirable. Nonetheless, there are often too many serious intra-professional barriers and obstacles to interprofessional collaboration to make it successful. Some of these barriers, it is argued and illustrated, are found in the multiple ways in which professional identity is tacitly acquired and embodied in the practitioners' habitual, everyday practice. The paper then explores ways in which reflection, especially Second order reflection, can help to elucidate and overcome these obstacles, as well as increasing professional adaptability and competence.  相似文献   

13.
This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.  相似文献   

14.
ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD and monthly online. The January 2011 issue (first quarterly DVD for 2011) contains 4515 complete reviews, 1985 protocols for reviews in production, and 13,521 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 641,000 randomized controlled trials, and 14,018 cited papers in the Cochrane methodology register. The health technology assessment database contains over 9300 citations. One hundred and seven new reviews have been published in the last 3 months, of which five have potential relevance for practitioners in pain and palliative medicine.  相似文献   

15.
目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4%(55/72)]明显高于成功组[31.7%(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3%(42/72)]高于成功组[38.1% (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9% (28/72)]高于成功组[23.8%(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大<6 cm、胎头位于坐骨棘上及宫口开大8~10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1%(44/72)]高于成功组[38.9%(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2%(52/72)]明显高于成功组[34.1 %(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.  相似文献   

16.
17.
Ranganath C  Heller AS  Wilding EL 《NeuroImage》2007,35(4):1663-1673
Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.  相似文献   

18.
The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.  相似文献   

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目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高<20%视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P<0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P<0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P<0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.  相似文献   

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