高强度聚焦超声联合超声造影剂消融兔肝后细胞凋亡和增殖细胞核抗原表达的研究

目的：探讨高强度聚焦超声（HIFU）联合超声造影剂消融技术对兔肝组织细胞凋亡和增殖细胞核抗原（PCNA）表达的影响。方法：40只新西兰纯种大白兔分为A、B组，A组兔肝接受HIFU辐照前，经耳缘静脉注射生理盐水；B组接受辐照前注射超声造影剂SonoVue。A、B组均在辐照后5min、1d、3d、7d、14d分别处死4只动物，将肝取出体外观察，取靶区及周围组织（距靶区边缘5mm以内），HE染色观察组织病理学改变，原位末端标记法（TUNEL）检测细胞凋亡，免疫组织化学方法检测细胞PCNA表达。结果：HIFU辐照后3d、7d、14dB组辐照区域边缘纤维包裹带宽度大于A组（P〈0．05）。HIFU辐照后1d、3d、7d、14dB组靶区周围组织（距靶区边缘5mm以内）凋亡细胞数和PCNA阳性细胞指数较A组增高（P〈0．05）。结论：与单纯HIFU相比，HIFU联合超声造影剂促进了消融后坏死区域机化包裹，增加了HIFU靶区周围细胞凋亡，提高了细胞增殖能力，为进一步增强HIFU消融作用提供了实验数据。     

超声造影剂增强HIFU消融兔肝组织的电镜观察

目的探讨高强度聚焦超声(HIFU)联合超声造影剂消融后兔肝细胞超微结构变化。方法30只动物分为两组,A组单纯HIFU辐照,B组辐照前注射超声造影剂。辐照后1h、6d、14d电镜观察。结果辐照后两组靶区细胞坏死,辐照后早期A组靶区可见细胞轮廓。辐照后6d两组靶区细胞崩解,边缘见纤维包裹带,靶区周围细胞浊肿,B组较A组严重,B组靶区周围凋亡小体多于A组。结论超声造影剂增强HIFU消融作用,进一步破坏组织超微结构。     

不同剂量微泡造影剂在高强度聚焦超声消融活体羊肝组织中的增效效应

目的 探讨不同剂量超声造影剂对高强度聚焦超声(HIFU)消融活体羊肝组织的增效效应.方法 南疆黄羊20只,随机分为4组.第1组为HIFU联合0.01 ml/kg SonoVue.第2组为HIFU联合0.03 ml/kg SonoVue,第3组为HIFU联合0.05 ml/kg SonoVue,第4组为单纯HIFU组.麻醉状态下,微泡造影剂于HIFU辐照前静脉团注,20 s后开始HIFU辐照.每组采用定点辐照,所用辐照参数为频率0.8 MHz、声强19 100 W/cm2、辐照深度30 mm、辐照时间15 s.HIFU辐照结束后1周处死动物.观察并测量凝同性坏死大小,对凝固性坏死作组织病理分析.结果 在相同声辐照参数下,1、2、3组凝同性坏死区域均大于第4组,差异有统计学意义(P<0.05),且凝固性坏死体积随SonoVue剂量的增加而逐渐增大,差异有统计学意义(P<0.05).组织病理学检查发现凝同性坏死区内无正常组织残留.除实验3组出现消融灶邻近组织和皮肤损伤外,其余各组均未出现明显并发症.结论 微泡造影剂在HIFU消融过程中的增效效应与微泡造影剂的剂量有关,微泡造影剂的剂量越大,所形成的凝固性坏死的体积越大,增效越明显.     

高强度聚焦超声联合微泡损伤山羊肝的增效性研究

目的 探讨超声造影剂SonoVue用于增强高强度聚焦超声(HIFU)损伤山羊肝组织的可行性.方法 南江黄羊15只,采用自身对照,分为HIFU治疗组(对照组)和HIFU联合造影剂治疗组(实验组).治疗深度30 mm,分别在声功率为150 W、250 W、350 W条件下对肝定点辐照15 S.辐照后24 h处死动物,解剖观察凝固性坏死情况,并作病理切片分析.结果 在相同声辐照参数下,实验组凝固性坏死发生率及凝固性坏死区域长、宽、厚、体积均明显大于对照组(P＜0.05),随功率增加实验组凝固性坏死体积增加幅度较对照组更明显,实验组能效因子(EEF)明显小于对照组.凝固性坏死区与正常肝组织分界清楚,且病理切片显示损伤为不可逆性,分界处可见大量空泡.结论 HIFU联合微泡造影剂能在山羊肝中形成完全的凝固性坏死,同时提高凝固性坏死的损伤率,增大凝固性坏死体积,提高HIFU治疗效率.     

非消融高强度聚焦超声预辐照对超声消融兔肌肉效率影响的实验研究

目的 比较非消融高强度聚焦超声(HIFU)预辐照兔肌肉组织对超声消融效率的影响.方法 11只新西兰大白兔的66个肌性区域分为1组(A1、B1、C1)和2组(A2、B2、C2).在磁共振成像引导下,A组和B组采用较低强度HIFU预辐照使靶区温度分别达到45℃和50℃,C组假预辐照;次日,1组动物行病理学观察,2组动物行较高强度HIFU辐照.结果 2组中,A组、B组在较高强度HIFU辐照时靶区温度达到56℃所需的时间短于C组(A＜B);A组、B组凝同性坏死体积均大于C组(A＜B),消融能效因子均小于C组(A ＞B).1组靶庆组织未坏死,但有所损伤.结论 非消融HIFU预辐照能显著提高超声消融效率,且50℃效果好于45℃.     

超声造影剂对高强度聚集超声治疗兔肝VX2肿瘤的影响

目的探讨高强度聚焦超声（HIFU）联合超声造影剂治疗兔肝VX2肿瘤时，不同剂量的超声造影剂对治疗效应的影响。方法45只荷瘤兔随机分为三组：A组，单纯HIFU辐照组；B组和C组，均为联合辐照组，超声造影剂剂量分别为0．03ml／kg和0．05ml／kg。结果超声造影剂能够增强HIFU治疗效率，且超声造影剂的剂量越高，HIFU治疗效率提高越明显（P〈0．05）。结论超声造影剂可以提高HIFU治疗效率，而且超声造影剂剂量越高则HIFU的治疗效率越高。     

高强度聚焦超声消融胰腺癌安全性及疗效研究

目的评估高强度聚焦超声（HIFU）消融胰腺肿瘤的安全性及疗效。方法应用Jc型体外HIFU肿瘤治疗系统治疗不能手术切除的胰腺癌，通过治疗前后的增强影像评估肿瘤的消融体积，探讨其与超声治疗参数之间的关系。结果20例HIFU治疗的胰腺癌有l6例获得治疗后的消融影像评估，肿瘤消融比率平均为（55．9±33．7）％，HIFU洽疗的最大声功率与肿瘤消融比率呈正相关（r=0．686，P=0．020），高声功率治疗组（最大声功率≥300W）获得的肿瘤消融比率[（68．5±26．1）％]显著大于低声功率治疗组（最大声功率≤280W）获得的消融比率[（32．5±31．8）％，P〈0．05]。15例治疗前显著疼痛的患者有12例治疗后疼痛缓解或显著减轻。本组1例高声功率HIFU治疗后发生了肠系膜上动脉闭塞。结论使用较高的声功率，体外HIFU治疗能够有效地消融胰腺肿瘤和缓解疼痛，作为晚期胰腺癌的减瘤治疗措施，其安全性和临床意义值得进一步研究。     

多功能超声造影剂体外超声-磁共振双模态显像及增效高强度聚焦超声的实验研究

目的 制备一种新型的多功能超声造影剂,体外观察其超声、磁共振(MR)成像效果及增强高强度聚焦超声(high-intensity focused ultrasound,HIFU)消融效果.方法 采用双乳化法合成载超顺磁性氧化铁(superparamagnetic iron oxide,SPIO)纳米颗粒的高分子微球(s-PLGA),检测其一般性质.制备体外成像模型,应用超声诊断仪及磁共振扫描仪对不同浓度s-PLGA分别行超声及MR成像.另取新鲜离体牛肝,局部注射s-PLGA后,给予不同HIFU辐照参数,通过计算辐照区凝固性坏死体积评价s-PLGA增强HIFU消融效果.结果 制备的s-PLGA呈球形,平均直径为(885.6±133.2)nm.体外超声显像,sPLGA呈高回声,回声强度随浓度及机械指数减小而降低;磁共振T2WI呈负增强显像.注射s-PLGA后行HIFU辐照,辐照区凝固性坏死体积明显增大(P＜0.05).结论 自制的多功能超声造影剂-载超顺磁性氧化铁高分子微球具备超声、MR双模态复合成像与增效HIFU的功能.     

HIFU消融后兔肝细胞凋亡与增殖的研究

目的探讨高强度聚焦超声（HIFU）消融兔肝组织后细胞凋亡和增殖细胞核抗原（PCNA）表达的变化。 方法24只新西兰大白兔肝组织接受HIFU辐照，辐照后5min，1、3、6、9、14d分别处死4只动物，取出肝脏，HE染色观察组织病理改变，透射电镜观察细胞超微结构变化，原位末端标记法（TUNEL）检测细胞凋亡，免疫组织化学方法检测PCNA表达。 结果HE染色显示HIFu辐照后靶区边缘形成纤维包裹带，随时间逐渐加宽（P〈0．05）。电镜发现辐照后靶区周围组织有凋亡小体生成，TUNEL检测凋亡指数于辐照后3d最高。辐照后靶区周围组织出现PCNA阳性细胞，PCNA阳性细胞指数于辐照后6d达到峰值。 结论HIFU辐照后凝固坏死区域逐渐机化包裹，靶区周围组织出现凋亡细胞和PCNA阳性细胞，数量随时间变化，为进一步控制和增强HIFu消融作用提供实验基础。     

载10-羟基喜树碱靶向相变纳米粒联合高强度聚焦超声治疗裸鼠肝癌移植瘤

目的探讨叶酸受体靶向的载10-羟基喜树碱(10-HCPT)相变纳米粒(FR-HCPT-PNPCA)造影剂联合高强度聚焦超声(HIFU)对裸鼠肝癌移植瘤的治疗效果。方法采用皮下注射人肝癌7721细胞的方法制备荷瘤裸鼠模型120只,随机分为4组,每组30只,HIFU治疗前1 d分别通过尾静脉注射药物或生理盐水200μl,其中A组注射生理盐水+HIFU辐照,B组注射HCPT+HIFU辐照,C组注射靶向非载药相变纳米粒(FR-PNPCA)+HIFU辐照,D组注射FRHCPT-PNPCA+HIFU辐照。辐照后即刻应用超声观察各组裸鼠肿瘤内灰度变化。2 h后每组处死10只裸鼠,取肿瘤组织行TTC染色观察大体病理并进行组织切片,HE染色后于显微镜下观察肿瘤细胞坏死情况,然后行组织匀浆检查瘤内HCPT浓度。48 h后每组再处死10只裸鼠,取肿瘤组织切片行PCNA和TUNEL染色观察各组肿瘤细胞增殖和凋亡情况。2周后处死各组剩余裸鼠,测量肿瘤大小,并取主要脏器观察肿瘤转移情况。结果辐照后即刻超声显示A、B组辐照区域几乎无灰度变化,C、D组辐照前后灰度变化面积和变化值与A、B组比较,差异均有统计学意义(均P<0.05)。辐照后2h,B、D组瘤内均可检测到HCPT,且D组瘤内HCPT浓度高于B组,差异有统计学意义(P<0.05);A、B组均未见明显凝固性坏死,C、D组肿瘤内均可见明显凝固性坏死,坏死范围与A、B组比较差异均有统计学意义(均P<0.01)。辐照后48 h,D组细胞增殖率最低,细胞凋亡率最高,与A、B、C组比较差异均有统计学意义(均P<0.05)。辐照后2周,D组肿瘤几乎消失,转移灶最少,与A、B、C组比较差异均有统计学意义(均P<0.05)。结论FR-HCPT-PNPCA联合HIFU不仅能实时监控肿瘤HIFU消融并增强消融效果,且释放的药物能辅助治疗肿瘤,有望为肿瘤治疗提供一种精准、高效的方法。     

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.