fMRI观察强制戒断对海洛因成瘾者渴求任务下大型脑网络的影响

目的 探讨强制戒断对海洛因成瘾者毒品线索任务下心理渴求及脑网络功能的影响。方法 对37例强制戒断的海洛因成瘾者（强制戒断组）和32名正常志愿者（对照组）先行静息态及渴求任务fMRI数据采集,并进行心理渴求量化评分。对静息态fMRI数据进行分析获取任务负相关网络（TNN）和任务正相关网络（TPN）。对任务态fMRI数据进行建模,与对照组比较,获得强制戒断组TNN和TPN中异常激活的脑区,并分析其与心理行为学的相关性。结果 强制戒断组任务线索图片呈现前后渴求评分均显著高于对照组（P均<0.01）。渴求任务下,与对照组比较,强制戒断组在TNN中右侧海马旁回显著激活,TPN中显著性增强的网络包括视觉空间网络（双侧中央前回、额下回）和感觉运动网络（左侧中央后回）。强制戒断组双侧额下回激活强度与吸食海洛因时间呈负相关（右侧：r=－0.37,P=0.02;左侧：r=－0.41,P=0.01）。结论 强制戒断的海洛因成瘾者主观渴求依然增高,多个大型脑网络异常功能尚未完全恢复,可能是导致复吸的神经病理学基础。     

强制戒断时间对海洛因成瘾者大脑局部一致性影响的静息态功能MRI

目的 探讨静息态下强制戒断时间对海洛因成瘾者大脑局部一致性（ReHo）的影响。方法 纳入20例强制戒断6个月（戒断6个月组）、16例戒断11个月（戒断11个月组）的海洛因成瘾者和30名（正常对照组）人口学数据相匹配的健康受试者,采集其静息态fMRI数据,计算并比较3组间ReHo值,利用Pearson相关分析法分析差异脑区ReHo值与戒断时间的关系。结果 3组间ReHo值有统计学差异的脑区为左侧海马旁回、尾状核、岛叶、扣带回、中央后回及右侧眶额回。戒断11个月组ReHo值低于戒断6个月组的脑区为左侧海马旁回、尾状核、岛叶、扣带回及中央后回,右侧眶额回ReHo值高于戒断6个月组及正常组。左侧海马旁回（r=0.53,P=0.000 8）、尾状核（r=0.54,P=0.000 6）、岛叶（r=0.62,P<0.000 1）、扣带回（r=0.47,P=0.003 5）及中央后回（r=0.35,P=0.034 8）的ReHo值分别与戒断时间呈负相关,右侧眶额回（r=0.66,P<0.000 1） ReHo值与戒断时间呈正相关。结论 海洛因成瘾者多数受损脑区（渴求、抑制性控制及学习记忆等）经长期戒断后功能趋于恢复正常,而动机/驱动脑区（眶额回）活动异常增高可能是戒断后复吸的原因之一。     

静息态fMRI观察强制戒断与美沙酮维持治疗6个月对海洛因成瘾者脑功能的影响

目的 分析强制戒断（PA）和美沙酮维持治疗（MMT）干预6个月对海洛因成瘾者大脑功能影响的差异。方法 招募22例PA干预6个月的海洛因成瘾者（PA组）、25例MMT干预6个月的海洛因成瘾者（MMT组）和35名健康志愿者（正常对照组）。对所有受试者行fMRI采集静息态数据,利用低频振幅（ALFF）方法计算3组大脑局部自发性脑活动的强度,分析比较3组大脑ALFF差异。结果 3组在右侧额中回、左侧内侧额上回、左侧岛叶、左侧舌回、右侧舌回、右侧辅助运动区ALFF值差异有统计学意义（P均<0.01）,且PA组右侧额中回、左侧内侧额上回、左侧舌回、右侧舌回和右侧辅助运动区ALFF值与MMT组差异有统计学意义（P均<0.01）,PA组与正常对照组右侧额中回和右侧舌回ALFF值差异无统计学意义（P均>0.05）。结论 经6个月干预后,MMT者与PA者在部分脑区仍存在异常,但PA可能更有利于海洛因成瘾者脑功能恢复。     

DTI评价戒断时间对海洛因成瘾者大脑白质完整性的影响

目的 采用DTI研究戒断的时间效应对海洛因成瘾者大脑白质微结构的影响。方法 对28例短期戒断(sa组)与17例长期戒断(la组)的海洛因成瘾者进行DTI数据采集,组间FA比较采用白质骨架的空间统计(TBSS)方法,对组间人口学资料、径向弥散(RD)值和轴向弥散 (AD)值比较采用两样本t检验,对脑白质差异区的FA值与戒断时间进行相关分析。结果 与sa组比较,la组FA值升高的脑区包括左侧后冠状辐射、左侧外囊、左侧内囊后肢、右侧上纵束、右侧前冠状辐射、右侧皮质脊髓束、双侧上冠状辐射、胼胝体体部和压部 (P<0.05,TFCE及FWE校正),la组上述脑区的RD值降低(P<0.05),两组的AD值差异无统计学意义(P>0.05)。sa组和la组大脑白质差异区FA值与戒断时间呈正相关(r=0.361、0.380,P=0.019、0.013)。结论 接受长期戒断的海洛因成瘾者大脑多个区域的脑白质完整性较短期戒断者显著改善。长期戒断有利于海洛因所导致的白质损伤恢复,也可能有利于海洛因成瘾者认知功能等脑功能的改善。     

静息态fMRI观察终末期肾病患者执行功能障碍相关自发脑活动异常

目的 采用静息态fMRI（rs-fMRI）及低频振荡振幅（ALFF）算法探讨终末期肾病（ESRD）患者执行功能障碍相关的自发脑活动异常。方法 收集35例ESRD患者（ESRD组）和32名性别、年龄匹配的健康志愿者（对照组）,对其行连线测试（TMT）评估及rs-fMRI;采集ESRD组患者实验室检查指标,包括血清肌酐、血红蛋白、尿素和胱抑素C。采用SPM8及REST l.8软件,获得2组平均ALFF图;提取2组间ALFF差异有统计学意义的脑区,以Pearson相关性分析评价差异脑区的平均ALFF值与TMT评分及实验室检查指标的相关性。结果 与对照组比较,ESRD组患者双侧额中回、双侧楔前叶、双侧额内侧回、双侧扣带回、双侧颞中回、左侧枕中回及右侧额上回平均ALFF值减低（P均<0.001,FDR校正）,无平均ALFF值增高脑区。ESRD组左侧额中回（r=-0.57,P<0.001）及中扣带回（r=-0.55,P<0.001）平均ALFF值与TMT评分呈负相关。ESRD组前扣带回（r=0.63,P<0.001）、左侧额中回（r=0.64,P<0.001）及左侧颞中回（r=0.51,P<0.001）平均ALFF值与血红蛋白水平呈正相关。差异脑区平均ALFF值与ESRD组血肌酐、尿素、胱抑素C水平均无明显相关（P均>0.05）。结论 ESRD患者左侧额中回及中扣带回自发脑功能异常与执行功能障碍密切相关,左侧额中回自发脑活动异常与贫血密切相关,有望成为评估ESRD患者执行功能障碍及治疗监测的影像学标记。     

阿尔茨海默病患者脑功能网络小世界属性改变及其与认知功能的相关性

目的 利用图论分析方法观察阿尔茨海默病（AD）患者脑功能网络小世界属性改变及其与认知功能的相关性。方法 对42例AD患者（AD组）和31名正常志愿者（对照组）进行神经心理学评估,并采集静息态fMRI数据,构建小世界网络,计算小世界网络属性参数,包括聚类系数（C_p）、最短路径长度（L_p）、标准化聚类系数（γ）、标准化最短路径长度（λ）及小世界性（σ）。以独立样本t检验比较2组间小世界网络属性的差异,以偏相关分析评估小世界网络属性与认知评分的相关性。结果 在不同稀疏度下,AD组及对照组σ均>1,表示AD患者及正常受试者脑功能网络均具有小世界属性。AD组小世界属性参数L_p、λ大于对照组（P均<0.05）,AD组与对照组间C_p、γ差异均无统计学意义（P均>0.05）。AD患者C_p与听觉词语学习测验（AVLT,即时）、AVLT（延迟）评分呈正相关（r=0.646,P<0.001;r=0.438,P=0.008）,L_p与AVLT（即时）评分呈负相关（r=-0.381,P=0.035）。结论 AD患者脑功能网络的小世界属性发生改变,且与情景记忆能力具有相关性。脑功能网络小世界属性改变能够较好地反映AD患者的病理生理改变。     

头颈部CTA联合全脑CT灌注一站式扫描中时间间隔对灌注参数的影响

目的 探讨头颈部CTA联合全脑CT灌注（CTP）一站式扫描中,时间间隔对灌注参数的影响。方法 回顾性分析60例急性脑缺血症状患者的标准脑CTP图像（标准组）,于颅脑CTP图像中将动脉峰值期前后各1组扫描数据剔除,使得其前后间隔时间增加至4.5 s,模拟头颈部CTA联合全脑CTP一站式扫描（模拟组）。计算标准组与模拟组灌注参数[脑血流量（CBF）、脑血容量（CBV）、平均通过时间（MTT）]绝对百分比误差值,并分析脑灰质左侧与右侧、白质左侧与右侧灌注参数比值（rCBF、rCBV、rMTT）的相关性。结果 基底核层面CBF、CBV、MTT的绝对百分比误差值均值均<10%。灰质左侧与右侧rCBF（r=0.988,P<0.001）、rCBV（r=0.963,P<0.001）、rMTT（r=0.983,P<0.001）均呈正相关,白质左侧与右侧rCBF（r=0.980,P<0.001）、rCBV（r=0.957,P<0.001）、rMTT（r=0.986,P<0.001）均呈正相关。结论 头颈部CTA联合全脑CTP一站式扫描中时间间隔对灌注参数的影响较小。     

维持性血液透析患者脑体积变化及其与睡眠质量、焦虑及抑郁的相关性

目的 采用基于体素的形态学测量（VBM）法观察终末期肾病（ESRD）维持性血液透析患者脑体积变化及其与睡眠质量、抑郁及焦虑的相关性。方法 对20例ESRD维持性血液透析患者（病例组）和21名健康志愿者（正常对照组）行MR扫描及神经心理学量表测评,包括蒙特利尔认知评估量表（MoCA）、匹兹堡睡眠质量指数量表（PSQI）、焦虑自评量表（SAS）与抑郁自评量表（SDS）。比较2组间脑体积变化,分析病例组脑体积变化区域与神经心理学测量评分的相关性。结果 与正常对照组相比,病例组左侧颞中回、右侧额中回及左内侧额上回的脑灰质体积减小（P均<0.001,AlphaSim多重校正后）;2组间MoCA、PSQI、SAS及SDS评分差异均具有统计学意义（P均<0.05）。病例组左侧颞中回体积减小分别与PSQI、SDS及SAS评分呈负相关（r=-0.588、-0.456、-0.489,P=0.006、0.043、0.029）;右侧额中回体积减小分别与SDS及SAS评分呈负相关（r=-0.495、-0.466,P=0.026、0.038）;左内侧额上回体积减小分别与MoCA评分呈正相关（r=0.462,P=0.040）,与PSQI评分呈负相关（r=-0.588,P=0.006）。结论 ESRD维持性血液透析患者部分脑灰质体积萎缩,并有认知功能下降;伴睡眠质量差、焦虑或抑郁者可能与相应脑灰质体积减少有关。     

静息态fMRI观察脊髓型颈椎病患者初级躯体感觉皮层功能连接

目的 采用静息态fMRI观察脊髓型颈椎病（CSM）患者大脑初级躯体感觉皮层（S1）功能连接的改变。方法 对33例CSM患者（CSM组）及23名健康志愿者（对照组）行静息态fMRI,将双侧S1各分为6个感觉亚区（手指、上肢、下肢、胸部、背部和头面部）作为ROI,提取ROI信号,并与大脑其他脑区行基于体素水平相关性分析,获得功能连接系数并构建功能连接图;以双样本t检验比较CSM组与对照组间大脑功能连接的差异,并分析差异脑区功能连接值与临床功能量表评分间的相关性。结果 与对照组比较,静息状态下CSM组S1左侧上肢感觉亚区与左侧角回、左侧颞下回、右侧颞中回功能连接减低;S1左侧下肢感觉亚区与左侧角回功能连接减低;S1右侧胸部感觉亚区与双侧角回、双侧额上回、左侧内侧额上回、左侧额中回、左侧颞中回/颞下回、右侧小脑后叶功能连接减低;S1右侧下肢感觉亚区与左侧角回功能连接减低（P<0.05,FDR校正）。CSM患者S1左侧上肢感觉亚区与左侧角回的功能连接值与颈椎功能障碍指数评分（NDI）呈负相关（r=-0.377,P=0.031）;S1左侧上肢感觉亚区与左侧颞下回的功能连接值与上肢感觉日本骨科协会（JOA）评分呈正相关（r=0.353,P=0.044）;S1右侧下肢感觉亚区与左侧角回的功能连接值与下肢感觉JOA评分呈正相关（r=0.406,P=0.019）。结论 CSM患者存在与感觉运动相关功能连接异常,提示CSM患者已发生大脑皮层功能重组。     

经典三叉神经痛患者脑局部自发活动的静息态功能MRI

目的 观察经典三叉神经痛（CTN）患者静息状态下脑局部自发活动的改变。方法 对27例CTN患者（CTN组）和27名健康对照者（对照组）行静息态脑功能MRI数据采集,采用局部一致性（ReHo）数据分析方法获得CTN组ReHo差异脑区,并对组间差异脑区ReHo值分别与患者视觉模拟评分（VAS）和病程行相关性分析。结果 与对照组比较（P<0.05,高斯随机场校正）,CTN患者双侧初级感觉运动皮层,右侧辅助运动区、颞下皮层和小脑,左侧丘脑、边缘叶/海马旁回和颞上/中皮层ReHo值增高;双侧前额皮层/眶额皮层和脑岛,右侧额内侧皮层和颞上皮层,左侧前扣带回、缘上回和小脑ReHo值减低。右额内侧皮层ReHo值与病程呈负相关（r=-0.45,P=0.03）;左侧初级感觉运动皮层ReHo值与VAS评分（r=0.46,P=0.02）呈正相关。结论 CTN患者存在疼痛相关功能脑区自发功能活动一致性的异常,有助于对CTN发生机制的理解。     

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.