血清脂蛋白(a)水平与血管内超声斑块显像特征的关系

目的观察不同类型冠心病患者血清脂蛋白(a)[Lp(a)]水平及在血管内超声(IVUS)下冠状动脉斑块显像特征关系。方法选择在我院住院急性冠状动脉综合征(ACS)患者88例,稳定型心绞痛(SAP)患者72例,同时选取在门诊因胸痛就诊,行冠状动脉造影显示正常的患者80例作为对照组,测定三组患者血清Lp(a)水平,应用IVUS评价ACS组和SAP组患者冠状动脉斑块的形态、特征及易损性。并进一步评价血清Lp(a)与IVUS评价易损性斑块指标的相关性。结果 ACS组血清Lp(a)浓度显著高于SAP组及对照组(均P<0.01),ACS组狭窄病变处主要为软斑块、偏心性斑块,而SAP组则反之,ACS组IVUS斑块面积(P<0.01)、偏心指数及重构指数(P均<0.05)均大于SAP组,管腔面积小于SAP组(P<0.01),血浆Lp(a)水平与软斑块面积百分比、偏心指数和血管重构指数(r=0.365,P=0.011;r=0.448,P=0.008和r=0.432,P<0.001)呈正相关。结论 ACS组血清Lp(a)水平明显高于SAP组和对照组,血清Lp(a)水平与IVUS评价斑块易损性指标相关,Lp(a)可作为冠状动脉易损斑块的评估因子。     

血管内超声评价造影无显著狭窄的心绞痛患者斑块特点的研究

目的研究血管内超声显像(IVUS)对评价冠状动脉造影无显著狭窄病变的心绞痛患者冠状动脉内斑块特点的临床意义和治疗价值。方法选取稳定和不稳定型心绞痛患者52例,所有患者均经冠状动脉造影证实冠脉狭窄均<50%,其中靶血管累及LAD(左前绛支)26例、RCA(右冠动脉)15例、LCX(左回旋支)11例。对所有患者行IVUS检查。结果①定性分析:52例52处病变中偏心性斑块33例(63.4%),向心斑块19例(36.5%),其中软斑块32例(61.5%),纤维斑块10例(19.2%),钙化斑块6例(11.5%),混合型斑块4例(7.7%)。52例中斑块破裂14例(26.9%);1例发现血栓(1.9%)。②定量分析:冠状动脉造影结果测得管腔面积为9.4±3.6 mm2,面积狭窄率为(45.2±5.4)%,IVUS测得管腔面积为5.8±2.1 mm2,面积狭窄率为(65.6±8.9)%。两者测得的数值比较差异均有显著性(P<0.05)。根据IVUS检查结果,22例进行了支架植入术。结论IVUS对评价冠状动脉造影无显著狭窄的心绞痛患者动脉斑块特点、狭窄程度、指导治疗有重要的临床价值。     

双源螺旋CT与血管内超声对冠状动脉斑块和血管重塑的比较

目的以血管内超声(IVUS)为标准,评价双源螺旋CT(DSCT)对冠状动脉斑块、血管重塑的临床应用价值。方法入选拟诊为冠心病的17例患者,分别行DSCT和IVUS检查,以10mm为一评估节段,分别评估每个有效节段斑块的性质和CT值,并测定管腔面积、斑块面积、斑块负荷和血管重塑指数。结果在21支冠状动脉的114段可评估的冠状动脉节段中,DSCT对斑块诊断的敏感性为88.10%(37/42),特异性为95.83%(69/72),阳性预测值为92.50%(37/40),阴性预测值为93.2%(69/74)。DSCT和IVUS对管腔面积、斑块面积和斑块负荷的测量值分别为:(6.79±3.29)mm~2比(6.80±2.79)mm~2;(8.89±5.44)mm~2比(8.24±3.05)mm~2;(55.26±13.32)%比(55.09±9.42)%(P0.05)。相关系数分别为0.81,0.75和0.51(P0.01)。以IVUS结果将斑块分为脂质斑块、纤维斑块和钙化斑块,分别测得CT值为(54.50±5.59)HU(117.90±13.79),HU(780.18±134.73)HU(P0.01)。两两比较发现脂质斑块和纤维斑块的CT值无显著性差异(P=0.44)。DSCT与IVUS对血管重塑指数相关性检验,r=0.38,P0.05。结论与IVUS比较,DSCT是一种能有效检测冠状动脉粥样斑块的无创检查方法,能准确的评估冠脉临界病变的管腔面积、斑块面积及斑块负荷,能有效评估冠状动脉钙化和非钙化成分,对血管重塑性的评估与IVUS测量结果相关。     

冠状动脉不稳定斑块的血管内超声影像分析

目的　探讨血管内超声 (intravascularultrasound ,IVUS)判定不稳定斑块的敏感性及特异性。方法　 43例确诊冠心病患者在冠状动脉造影 (coronaryangiography ,CAG)后行IVUS检查 ,根据斑块回声强弱分为软斑块组和硬斑块组 ,两组分别进行定量测定。结果　急性冠状动脉综合征者IVUS检出软斑块 2 2例 (2 2 /2 7) ,占 81.4% ,IVUS检测不稳定斑块的敏感性 81.4% ,特异性 75.0 % ,准确性 79.1% ,阳性预测值 84.6%。软斑块组脂核面积比硬斑块组的无回声区面积明显增大 (P <0 .0 1) ;脂核与斑块比软斑块组明显大于硬斑块组 (2 6.4%± 11.5%对 12 .0 %± 7.0 % ,P <0 .0 1) ;软斑块组纤维帽厚度明显小于硬斑块组 [(0 .3 8± 0 .14 )mm对 (1.17± 0 .3 6)mm ,P <0 .0 1] ;在面积狭窄率上 ,软斑块组明显小于硬斑块组 (62 .6%± 6.9%对 70 .9%± 7.5% ,P <0 .0 1) ;偏心程度软斑块组明显大于硬斑块组 (92 .9%对82 .4% )。两组间斑块大小差异无显著性意义 [(10 .70± 2 .96)mm2 对 (10 .84± 3 .48)mm2 ,P >0 .0 5]。结论　IVUS对冠状动脉不稳定斑块的判定具有较高的敏感性和特异性     

血管内超声虚拟组织学对急性冠脉综合征患者冠状动脉斑块诊断的临床研究

目的 观察急性冠脉综合征(ACS)患者冠状动脉(冠脉)血管内超声虚拟组织学(IVUS-VH)影像,探讨冠脉易损斑块的影像学特点及与血脂水平的相关性.方法 回顾性分析42例ACS患者与40例自发性心绞痛(SA)患者通过IVUS-VH成像冠脉斑块的影像学特点及两组患者冠脉斑块的性质及其与临床血脂水平的相关性.结果 ACS组易损斑块总发生率明显高于SA组[36.7%(94/256)比14.6%(28/192),P<0.01],且近中段(<20 mm)易损斑块发生率明显高于远端(>30 mm,均P<0.01);ACS组斑块成分中纤维成分(F)、纤维脂质成分(FF)、坏死成分(NC)、钙化成分(DC)及血管重构指数(RI)与SA组比较差异均有统计学意义(P<0.05或P<0.01),其中ACS组以FF和NC成分为主,SA组以F和DC成分为主.两组血管斑块面积百分比(PAV)、斑块偏心指数(EI)差异无统计学意义(均P>0.05).易损斑块脂质成分FF与低密度脂蛋白呈正相关(r=0.08,P＜0.05),与高密度脂蛋白呈负相关(r=-0.06,P＜0.05).结论 IVUS-VH成像显示ACS患者易损斑块发生率明显高于SA患者,且斑块成分不同,与临床血脂水平具有相关性.     

体表超声评价急性冠脉综合征患者颈动脉粥样硬化性血管重构

目的:应用高频体表超声观察急性冠脉综合征患者颈动脉粥样硬化时颈动脉重构的改变。方法:选择2002/2003在山东大学齐鲁医院就诊的急性冠脉综合征(n=35)和稳定型心绞痛(n=25)患者共62例,采用荷兰菲利蒲SONOS-5500型彩色多普勒超声诊断仪检测,得出颈动脉血管总面积、血管腔面积、斑块面积、偏心指数、斑块面积狭窄百分率,计算重构指数(狭窄处血管总面积比参考血管总面积)。重构指数>5%为正性重构,<5%负性重构,在±5%之间为无重构。比较急性冠脉综合征和稳定性心绞痛患者颈动脉重构的差异。结果:62例全部进入结果发分析。①血管总面积与斑块面积呈正相关(r=0.51,P<0.05),血管腔面积与斑块面积之间无相关性(r=0.07,P>0.05)。②向心性斑块狭窄处血管总面积与参考血管总面积比较差异显著眼(72.67±22.18),(63.69±14.72)mm2,P<0.05演,可见明显的血管正性重构,而偏心性斑块血管重构不明显(P>0.05)。③脂质型+纤维脂质型斑块狭窄处血管总面积与参考血管总面积比较显著升高眼(71.86±22.65),(63.79±19.96)mm2,P<0.05演。可见明显的血管正性重构。④急性冠脉综合征组颈动脉斑块血管段正性重构38个,负性重构20个;稳定型心绞痛组斑块血管段正性重构9个,负性重构21个,两组比较差异显著(χ2=10.024,P=0.002)。结论:外周血管超声是检测颈动脉血管重构的一种可靠方法,急性冠脉综合征患者颈动脉血管重构以正性重构为主。     

血管内超声与血管造影检测早期左冠状动脉主干病变的对比研究

目的:通过血管内超声(IVUS)研究左冠状动脉主干(LMCA)动脉粥样硬化病变的发生率以及血管重塑的效应。方法:41例血管造影正常的LMCA行IVUS检查,计算LMCA的外弹力膜面积(血管面积)、管腔面积、斑块面积以及百分面积狭窄。结果:23例(56％)LMCA含有粥样硬化斑块。74％的斑块呈偏心性。含有斑块的LMCA血管面积19.6mm2±3.8mm2,与斑块面积(6.0mm2±2.7mm2)呈中度正相关(r=0.49,P<0.01)。平均面积狭窄为30.5±12.7％(6.4-68.6％)。含有斑块的LMCA血管面积比无斑块者(15.7mm2±1.9mm2,P<0.001)更大。结论:血管造影低估了LMCA粥样硬化病变的发生率。随着斑块的增长,LMCA出现代偿性扩张。IVUS是检测LMCA病变的重要方法。     

心肌梗死相关冠状动脉的腔内超声研究

目的　比较心肌梗死相关冠状动脉造影和血管内超声下粥样斑块的特征。方法　 2 5例急性心肌梗死患者的梗死相关动脉 (IRA)在成功经皮冠状动脉腔内成形术 (PTCA)后即刻行冠状动脉内超声检查 ,结果与冠状动脉造影进行定量和定性比较。结果　①在PTCA部位 ,平均面积狭窄 5 0 %～ 70 % ,斑块横截面积是血管横截面积的 (5 0± 18) % ;②冠状动脉内超声下病变的近端和远端粥样硬化发生率为 70 % ,而冠状动脉造影下上述部位的病变率仅 30 % (P =0 .0 0 1) ;③ 6 9%的斑块属于软斑块 ,硬斑块占 31% ,但是其斑块面积却大于前者 [(5 0± 16 ) %vs (39± 19) % ,P =0 .0 1] ;④PTCA部位所有近端与远端参考段血管腔内斑块面积与血管横截面积之间相关性良好 (r =0 .49,P =0 .0 0 0 1) ,病变段血管腔内斑块面积与血管截面积之间相关性良好 (r =0 .49,P =0 .0 0 3)。结论　冠状动脉内超声下梗死部位斑块负荷极重 ,同时病变的近远端存在广泛性粥样硬化和代偿性扩张     

应用血管内超声评价冠状动脉重塑与临床综合征的关系

目的：探讨冠状动脉重塑类型与心绞痛临床特点的关系。方法：对49例急性冠状动脉综合征（ACS）和26例稳定型心绞痛（SA）患者的“罪犯”病毒进行血管内超声检查。重塑指数定义为病变处血管面积与病变近端参照部位血管面积的比值，如重塑指数＞1．1为代偿性重塑，重塑指数＜0．9为收缩性重塑，重塑指数在0.9与1．1之间为无重塑。斑块回声强度低于血管外膜回声者为软斑块。结果：软斑块在ACS组与SA组产差异无显著性意义（ACS组59％，SA组46％，P＞0．05）。ACS患者代偿性重塑明显高于SA组（ACS组49％，SA组12％，P＜0．01），而SA患者收缩性重塑明显高于ACS组（ACS组31％，SA组69％，P＜0．01）。结论：应用血管内超声成像技术评价冠状动脉重塑，同斑块的性质相比，与心绞痛的临床特点更为密切相关。     

冠状动脉不稳定斑块血管内超声特征的临床研究

目的　探讨冠状动脉不稳定斑块的血管内超声 (IVUS)的特点。方法　在 31例急性冠脉综合征 (ACS,其中不稳定心绞痛 19例 ,急性心肌梗死 12例 )和 12例稳定性心绞痛患者中进行冠状动脉造影及 IVUS检查。应用 IVUS分别观察比较冠状动脉内斑块的性质 ,同时测量冠脉病变部位及其参考部位的血管外弹力膜面积 (EEMA)、管腔面积 (L A)、斑块面积 (PA)及管腔面积狭窄率 ,并计算斑块的偏心指数 (EI)及血管的重构指数(RI)。结果　在 4 3例患者中发现 ,不稳定心绞痛与急性心肌梗死中脂质斑块分别占 73.7% (14 / 19)及 75 .0 % (9/ 12 ) ,而稳定性心绞痛主要为纤维性斑块及混合性斑块 ,脂质斑块仅占 8.3% (1/ 12 )。同时发现 9例急性冠脉综合征患者发生斑块破裂及血栓形成。与稳定性心绞痛的斑块相比较 ,不稳定心绞痛的斑块具有较大的偏心性 (P<0 .0 5 ) ,EEMA、 PA及管腔面积狭窄率明显大于前者 ,具有显著的统计学意义 (P均 <0 .0 0 1) ,不稳定斑块呈现明显的正性重构 ,占 74 .2 % (2 3/ 31) ,而稳定斑块主要表现为负性重构 ,占 75 .0 % (9/ 12 )。结论　 IVUS能够准确地识别 AS不稳定斑块 ,本研究为早期发现不稳定斑块并预测斑块破裂奠定了基础。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

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.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

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.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

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.     

Digital imaging among medical facilities

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.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

手转胎头术失败的原因与分娩结局临床分析

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.