能量多普勒声学造影评价醋酸瘤内注射治疗兔肝VX2肿瘤疗效的实验研究

目的：探讨应用能量多普勒超声学造影评价醋酸瘤内注射治疗兔肝VX2肿瘤疗效的可行性和有效性。方法：新西兰兔肝VX2肿瘤模型8只（4－5月龄;2．5－3．0kg;10个结节,直径1．3－1．6cm)在酸治疗前后分别进行能量多普勒声学造影检查及处死后病理检查,以评价治疗效果。结果：治疗前,在所有病灶能量多普勒声学造影均可检测出瘤内及瘤周血流信号。治疗24h后再次探测,10个结节中有8个未能测及血流信号,处死后病理检查证实其瘤灶完全坏死,另2个结节仍可测及瘤周血流,病理检查发现残存肿瘤组织。结论：能量多普勒声学造影评价醋酸瘤内注射治疗兔肝VX2肿瘤的疗效基本可靠。     

能量多普勒及造影增强超声观察微波凝固治疗兔VX2肝癌疗效的初步研究

目的　应用能量多普勒及超声造影在微波凝固治疗兔VX2 肝癌后进行疗效评价。方法　建立 10个VX2 肝癌模型 ,开腹对VX2 肿瘤行微波辐射 (波长 9mm)治疗 ,每次 60W× 12 0s。微波治疗前后均行二维、能量多普勒及超声造影 (Levovist ,3 0 0mg/ml,0 .3ml/kg)观察 ,取肿瘤标本行病理检查。结果微波治疗即刻二维超声示沿微波天线呈强回声窄带样改变 ,周围呈较宽而均匀的低回声 ,肿瘤边缘变得不清晰。微波治疗后能量多普勒检查 4只VX2 肿瘤结节见血流增强信号 ,而超声造影示 10只VX2 肿瘤结节均可见血流增强信号 ,病理证实为不完全坏死。结论　超声造影能更灵敏地评价微波凝固治疗VX2 肿瘤的疗效 ,残存瘤组织表现为肿瘤内持续造影增强。     

醋酸注射及微波凝固治疗兔肝VX2肿瘤的实验研究

目的　探讨醋酸注射及微波凝固治疗兔VX2 肝癌效果 ,并将二者进行对照研究。方法　将18只兔的 2 0个VX2 肝癌结节随机分为微波治疗组与醋酸治疗组 ,分别给予超声引导下醋酸注射及开腹直视下微波凝固治疗 ,治疗后行能量多普勒条件下超声造影 (Levovist)评价其疗效。标本行病理检查。结果　瘤内注射醋酸后呈现大部肿瘤组织及周边正常肝组织不规则坏死 ,病理证实为多处点片状或灶状坏死。微波治疗后呈现长椭圆形凝固区 ,病理证实为治疗后即刻为不完全坏死 ,2周后显示为完全坏死。结论　醋酸注射治疗凝固坏死程度强 ,但弥散性强 ,凝固范围不固定 ;微波热场分布均匀 ,坏死范围稳定可靠。     

能量多普勒声学造影对兔VX_2肝癌血管显像增强的实验研究

目的 :探讨能量多普勒声学造影技术在兔 VX2 肝肿瘤中的应用价值。方法 :10只患有 VX2 肝肿瘤的新西兰白兔经外周静脉注射 L evovist,采用 ATL HDI30 0 0型超声仪的能量多普勒显像观察肿瘤血管造影增强效果。结果 :造影后 6例显示为中等量血流 ,4例显示为多量血流 ,且肿瘤中心部位的血流显示率明显增高 ,造影前无一只显示中心部血流 ,造影后有 7只显示出中心部血流并有 3只可见滋养血管走行。血流分布形态也由造影前的点状分布为主变为造影后的条状分布为主。结论 :能量多普勒声学造影明显提高兔肝 VX2 肿瘤内血流的显示率。     

声学造影指导经皮药物注射治疗兔VX2肿瘤的作用

目的：评价氟碳声学造影在动态观察和指导经皮药物注射治疗兔移植肿瘤中的作用，并对比无水酒精、50％乙酸治疗VX2肿瘤的疗效。方法：20只新西兰白兔双侧股部种植VX2肿瘤12－21d后行无水酒精或50％乙酸注射治疗。治疗前后应用彩色、能量和脉冲多普勒造影检查，并根据造影后残留血流部位确定药物再次注射部位及剂量，至肿瘤内血流完全消失。结果：①超声造影显著增强肿瘤彩色、能量和脉冲多普勒血流信号，显示残留肿瘤血流。②50％乙酸治疗肿瘤将肿瘤细胞全部杀死；而酒精治疗后1枚肿瘤内见存活瘤细胞。结论：①氟碳声学造影是动态观察和指导肿瘤治疗的可靠方法；②50％乙酸治疗肿瘤疗效优于无水酒精。     

能量多普勒声学造影对兔VX2肝癌血管显像增强的实验研究

目的：探讨能量多普勒学造影技术在兔VX2肝肿瘤中的应用价值。方法：10只患有V2肝肿瘤的新西兰白兔经外周静脉注射Levovist,采用ATL,HDI3000型超声仪的能量多普勒显像观察肿瘤血管造影增强效果。结果：造影后6例显示为中等量血流,4例显示为多量血流,且肿瘤中心部位的血流显示率明显增高,造影前无一只显示中心部血流,造影后有7只显示出中心部血流并有3只可见滋养血管走行。血流分布形态也由造影前的点状分布为主变为造影后的条状分布为主,结论：能量多普勒声学造影明显提高兔肝VX2肿瘤内血流的显示率。     

二维及多普勒超声观察射频治疗兔VX2肝肿瘤早期疗效的实验研究

目的　评价超声在观察集束电极射频治疗兔VX2 肝肿瘤早期疗效中的作用。方法　超声引导下将 2 5只大白兔建立VX2 肝肿瘤模型 ,随机抽取 5只作为对照组 ,其余 2 0只作为治疗组进行射频治疗 ,分别于治疗前 1d和治疗后当日 ,3d ,7d及 14d对肿瘤形态学及血流动力学变化进行超声观察。在治疗后每次超声检测结束处死 5只大白兔 ,取肿瘤标本进行病理检查。结果　肿瘤射频治疗后 ,治疗区呈极不均匀斑点状强回声及低回声 ,瘤内血流信号全部消失 ,部分肿块瘤周局部区域仍有血流信号。治疗后肿块未见明显长大 ,治疗组肿块治疗后 14d明显小于相应时间对照组肿块 (P <0 .0 1)。病理证实极不均匀回声及血流信号消失区域即为肿瘤组织凝固坏死区域 ,局部仍有术前肿瘤回声特点及血流信号存在的区域即为残存肿瘤或治疗不完全的区域。结论　兔VX2 肝肿瘤射频治疗后凝固坏死区具有一定的声像图特异性表现 ,结合彩色多普勒血流显像及能量多普勒超声 ,对肝肿瘤疗效观察确切可行。     

多普勒声学造影与DSA检查对照观察兔肌肉VX2肿瘤血管的实验研究

目的与X线数字减影血管造影对比，探讨彩色多普勒和能量多普勒声学造影检测肿瘤血管特征的应用价值。方法将8只右侧股外侧肌肉种植有VX2肿瘤的新西兰大白兔经耳缘静脉注射自制的新型白蛋白氟碳声学造影剂，采用Acuson公司生产的Sequoia 512超声仪，分别应用彩色多普勒和能量多普勒显像观察肿瘤血管造影增强效果，并与DSA检查对照。结果二维超声检查8只荷瘤兔共发现病灶12个，呈圆形或类卵圆形，边界较清晰。造影后，肿瘤内血流显示率明显增高，血管形态变化明显，条状及分枝状血流数目增多，并有4例清晰显示滋养血管走行，与DSA检查结果相一致。结论彩色多普勒和能量多普勒声学造影(CDE)是检测肿瘤血流特征的重要手段。能量多普勒声学造影优于彩色多普勒造影显像。     

造影多普勒超声显像评价兔肌肉VX2肿瘤的血流灌注

目的 :评价造影多普勒超声显像对兔肌肉 VX2 肿瘤 (兔鳞癌 )血流灌注的作用。方法 :将 8只双侧股外侧肌肉种植 VX2 肿瘤的新西兰白兔经耳缘静脉注射氟碳微泡造影剂后 ,分别应用彩色多普勒、能量多普勒超声显像观察兔肌肉 VX2 肿瘤血流灌注情况并定量分析。结果 :造影后 ,增强了肌肉 VX2 肿瘤血管显示率及血流信号强度 ,造影前后比较 ,彩色多普勒血流显像视频密度增加 69.88,能量多普勒血流显像视频密度增加 94.49,二者比较 P<0 .0 1 ,延长了肿瘤血流显影时间。结论 :造影多普勒超声显像提高了兔肌肉 VX2 肿瘤血流灌注的显示 ,增强其血流信号。造影能量多普勒血流显像优于彩色多普勒血流显像     

能量多普勒造影评价微波治疗肝癌效果的应用

目的 探讨能量多普勒造影对微波治疗后肝癌血管的显像效果。方法 15例肝癌（24个病灶）1～2次微波治疗后经外周静脉注射Levovist观察癌内及癌旁造影前后的血流显像，并与病理结果相对照。结果 微波治疗后24个癌灶造影前无一例有血流显示。造影后19个病灶无血流显示者病理为完全性坏死；5个病灶有血流显示（1例瘤内，4例瘤旁），相应部位活检为完全性坏死，追加二次微波治疗，造影后未见血流显像，病理证实为完全坏死。结论 能量多普勒造影是评价微波治疗肝癌疗效的实用性方法之一。     

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.