慢性非流畅性失语患者语言加工特征的脑磁图研究

目的:研究慢性非流畅性失语患者大脑在图片命名过程中神经网络活动特征及与受损语言功能的关系.方法:非流畅性失语患者及年龄、性别、学历相匹配的健康成年人各5例,分别作为实验组和对照组.使用西方失语症成套测验评估受试者的言语功能,应用脑磁图(MEG)对受试者图片命名过程中大脑语言加工活动进行检测.结果:比较两组受试者在图片命名过程中相关大脑感兴趣区域(ROIs)在不同时间窗内的激活强度后发现:在图片命名的400-600ms时间窗内非流畅性失语症患者左脑Broca区的激活强度较对照组显著下降(P＜0.05),右脑的Broca同源区、Wemicke同源区、顶下小叶激活强度显著高于对照组(P＜0.05),右Broca同源区的激活强度与患者的失语商(AQ)正相关(r=0.886,n=5,P=-0.045).结论:慢性非流畅性失语患者存在右脑神经网络活动广泛上调,这种泛化在言语输出准备时期最为明显,提示与受损后大脑自发低水平的言语代偿有关.     

生物类与非生物类图片命名任务对大脑活动时空模式的影响

目的：探讨图片的语义类别对命名任务的影响，研究生物类和非生物类图片命名任务对正常大脑活动时空模式的影响。方法：入组健康成年右利手受试者10例，选取来自不同语义类别（生物类和非生物类）的图片20张，应用磁共振成像获取个体大脑结构，脑磁图（MEG）检测任务中的全脑活动。结果：在图片命名任务中，早期脑区激活从双侧枕叶开始，逐步向颞叶和顶叶扩散，最后额叶激活产生言语。在视觉相关时间窗内，生物类图片命名在右侧扣带回激活强度显著低于非生物类图片命名（P=0.0475），而生物类图片命名在双侧枕叶、左侧顶叶和左侧额叶均显著高于非生物类图片命名（均P＜0.05）。在语义相关时间窗内，生物类图片命名在双侧额叶显著高于非生物类图片命名（P＜0.05）。在语音相关时间窗内，生物类图片命名在双侧枕叶、左侧顶叶和左侧额叶均显著高于非生物类图片命名（均P＜0.05）。结论：生物类和非生物类图片命名相比，两者在颞叶的活动未见显著差异，但前者具有枕叶、顶叶和额叶优势激活。提示生物类图片可以更好地在相关时间窗内刺激相关功能脑区。     

词联导航训练法联合经颅直流电刺激改善失语症言语流畅度及命名能力的临床观察

目的:探讨词联导航训练法(word association navigation training,WANT)结合经颅直流电刺激(tDCS)改善慢性非流畅性失语症患者言语功能的治疗方案。方法:16例非流畅性失语症患者随机分为真刺激组(8例)和伪刺激组(8例)。真刺激组tDCS阳极置于左侧Broca区,阴极置于对侧肩部,电流强度为1.0mA,2次/天,20min/次,连续10d。伪刺激组每次tDCS刺激30s后停止。两组同时实施WANT训练。治疗前后进行西方失语症成套测试(WAB)、训练图片和未训练图片命名测试。结果:治疗前后两组WAB失语商(WAB-AQ)和图片命名测试得分均有显著提高(P0.05)。治疗后真刺激组训练图片命名得分和WAB中言语流畅度得分显著提高(P0.01)。未训练图片命名测试得分和WAB-AQ较伪刺激组改善明显(P0.05)。结论:词联导航训练法结合tDCS能更显著地改善慢性非流畅性失语症患者的言语流畅度和命名能力。     

孤独症谱系障碍儿童脑磁图静息态伽马频带脑功能网络探析

目的:研究孤独症谱系障碍(ASD)儿童静息态脑磁图伽马频带的脑功能网络特征.方法 :ASD儿童6名,健康对照9名.采集静息态脑磁图信号和磁共振数据,在信号源水平进行伽马频带信号在大脑皮层的功率谱密度分析,并计算相位转移熵,构建脑网络,用于患儿组和对照组比较.结果 :在脑网络节点激活程度方面,与对照组相比,患儿的伽马频带...     

卒中后失语非损伤侧脑电功率谱网络特征研究

目的 探索左侧损伤卒中后失语(PSA)患者右脑脑电(EEG)功率谱网络效应特点。方法 2018年12月至2019年6月,招募12例仅左脑半球损伤的PSA患者(PSA组)以及相匹配的健康成年人12例(健康对照组)。采用中国康复研究中心失语症检查(CRRCAE)评价语言功能,并采集脑电数据。对比Alpha和Theta功率谱功能连接特点,与语言亚项进行相关分析。结果 PSA患者右侧脑功能网络在中央区与额、顶及额顶联合区的Alpha与Theta频段功能连接增强,在颞顶、顶枕区与额、额顶、额中央区的Theta频段功能连接减弱。右侧顶枕区至中央区Alpha频段功能连接增强与患者语言表达能力降低相关(P < 0.05),而顶、顶枕与前额、额中央的Theta频段功能连接减弱与患者语言的说、读、抄写、听写和计算等能力相关( r= -0.676~-0.717, P < 0.05)。 结论 EEG功率谱网络可反映右脑功能网络重组情况,右脑额-顶-中央网络功能连接变化可能与PSA语言功能损伤密切相关,可作为PSA疗效评价客观指征。     

Broca失语患者语言加工偏侧化特征的脑磁图研究

摘要 目的：从时间和空间维度,应用脑磁图（MEG）研究探讨慢性恢复期Broca失语症患者图片命名语言加工的半球偏侧特征。 方法：选取未经言语训练的慢性恢复期Broca失语症患者及与其年龄、性别、受教育程度相匹配的右利手健康成人各5例,分别设为实验组和对照组。应用脑磁图（MEG）检测语言加工过程的神经活动。采用偏侧指数（LI）确定语言加工过程总体及特定感兴趣区（ROIs）的偏侧优势,选取LI≤-0.1表示右侧优势;LI≥0.1表示左侧优势。 结果：与对照组相比,语言加工全过程实验组总体ROIs呈右偏侧优势,差异具有显著性意义（P＜0.01）;语言加工子过程,实验组在275—400ms、400—600ms、600—800ms时间窗内总体ROIs呈右偏侧优势,差异具有显著性意义（P＜0.01）。具体ROIs水平,实验组Broca区、Wernicke区、缘上回、前运动区在既定的语言加工子过程中呈右偏侧优势,差异具有显著性意义（P＜0.05）。 结论：Broca失语患者图片命名语言加工过程呈右偏侧优势,右偏侧优势具有时间窗和脑区效应。     

经颅直流电刺激背外侧前额叶对脑卒中后失语症患者命名和音位流畅性的影响

目的 观察经颅直流电刺激(tDCS) 脑卒中后失语症患者左侧背外侧前额叶（DLPFC）对其图片命名速度、图片命名正确率和音位流畅性的影响。 方法 采用随机数字表法将脑卒中后失语症患者24例分为观察组和对照组,每组患者12例。2组患者均进行语言训练和图片命名训练,观察组在图片命名训练的同时给予左侧背外侧前额叶tDCS治疗,每日1次,每次20 min,每周治疗6 d,连续治疗2周。对照组患者仅给予假tDCS治疗。于治疗前、治疗2周后分别对患者进行图片命名速度和正确率,以及音位流畅性测试。 结果 治疗2周后,2组患者高频词的准确数和反应时间与组内治疗前比较,差异均有统计学意义（P<0.05）,且观察组治疗2周后高频词的反应时间显著少于对照组治疗2周后,差异有统计学意义（P<0.05）。治疗2周后,观察组低频词的反应时间与组内治疗前比较,差异有统计学意义（P<0.05）。治疗2周后,观察组的音位流畅性为［7.50（4.50,8.75）］个,显著优于组内治疗前和对照组治疗2周后,差异均有统计学意义（P<0.05）。 结论 对脑卒中后失语症患者的左侧背外侧前额叶进行tDCS,可以促进其大脑网络词汇检索的处理,加强患者的执行控制功能。     

同类图片命名中信息处理的脑磁图研究

目的:应用脑磁图(MEG)检查,探讨同类图片命名任务中大脑的时空激活模式,为临床言语治疗提供依据。方法:选取健康成年右利手受试者10例(男性5例,女性5例)。实验任务为出声命名相同类别的图片。应用磁共振(MRI)获取个体大脑结构图像,通过脑磁图(MEG)检测图片命名过程中,全脑在不同时间窗内的激活水平。结果:在特征提取和语义编码时间窗内,视觉系统和腹侧颞叶联合系统的激活水平显著高于内侧默认模式系统(P0.01),其中腹侧颞叶联合系统的左侧半球的激活水平显著高于右侧半球(P0.05);在语音编码及发音发声时间窗内,腹侧颞叶联合系统、额-顶系统、扣带回-岛盖系统、注意系统、视觉系统以及听觉系统的激活水平均显著高于内侧默认模式系统(P0.01),其中腹侧颞叶联合系统、额-顶系统和听觉系统的左侧半球的激活水平显著低于右侧半球(P0.05)。结论:同类图片命名任务中,大脑随时间出现偏侧化优势激活。左偏侧化出现在信息处理过程的前期,与视觉特征提取和语义加工有关;右偏侧化出现在信息处理过程的后期,与语音加工有关。语义腹侧流和语音背侧流的时空分离现象为临床精准治疗提供了依据。     

脑磁图表现对脑卒中患者脑功能损伤程度和区域的评估价值

目的:分析2例出血性脑卒中术后患者的脑磁图表现,探讨脑磁图的研究现状以及在脑血管疾病方面的应用价值。方法:2003-12/2004-01在广东三九脑科医院电生理中心脑磁图室对2例经CT确诊为脑出血并已行引流术的患者进行脑磁图检查。结果:患者于清醒、安静状态下行自发脑磁图检查,在患侧半球发现异常低频磁活动(ALFMA);手指电刺激所得体感皮质诱发反应,发现患侧半球反应波消失。结论:脑磁图能确定大脑功能损伤的程度和区域,对出血性脑卒中患者脑损伤的诊断及其指导早期康复治疗很有帮助。     

不出声与出声图片命名任务神经激活机制差异的功能磁共振成像

目的 采用功能磁共振成像(fMRI)技术观察执行不出声和出声图片命名任务时大脑活动的差异.方法 在10名健康志愿者(24～27岁)分别进行不出声和出声图片命名时,同时采集其脑部的fMRI数据,通过分析处理获得执行不同任务时的头动结果及脑功能区统计激活图.结果 不出声任务的平均头动和最大头动低于出声任务,但差异无统计学意义(P=0.23).不出声图片命名的神经激活网络包括双侧枕回及小脑、双侧辅助运动区、中央后回、双侧额下回和前扣带回.出声图片命名时除在上述不出声时的激活区有更强激活外,还激活了双侧中央前回(BA4)、双侧后上颞回、左侧前上颞回、双侧丘脑及基底节区、左侧岛叶.结论 不出声和出声图片命名的神经处理网络及环节互不相同,两种任务不能相互替代.     

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.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.