膝部损伤后膝关节功能障碍患者股四头肌的表面肌电信号研究

目的 探讨膝部损伤后膝关节功能障碍对股四头肌功能的影响.方法 对23例单侧膝部损伤后膝关节功能障碍患者,膝屈曲30°,记录最大伸展等长收缩(MIVC)时的力矩,股外侧肌、股内侧肌和股直肌的表面肌电信号.结果 在患侧膝屈曲30°膝最大伸展MIVC时的力矩,股外侧肌、股内侧肌和股直肌的平均肌电值(AEMG)、平均功率频率(MPF)、中位频率(MF)均低于健侧(P＜0.01);健侧股外侧肌的AEMG、MPF大于股内侧肌、股直肌(P＜0.01或P＜0.05), 股直肌大于股内侧肌(P＜0.05);患侧股直肌的AEMG、MPF大于股外侧肌、股内侧肌(P＜0.01或P＜0.05);股外侧肌大于股内侧肌(P＜0.05).结论 sEMG能够定量评价膝部损伤后膝关节功能障碍患者的肌肉功能.膝关节功能障碍患者患肢肌力及股四头肌受累肌肉活动水平显著降低,股直肌可能受影响程度较轻.     

脑卒中偏瘫患者股直肌和股二头肌的表面肌电信号特征

目的：观察脑卒中偏瘫患者在最大等长收缩（MIVC）时股直肌和股二头肌的表面肌电信号特征，为脑卒中患者的康复提供客观依据。方法：选择26例恢复期的脑卒中患者，在进行膝关节屈、伸肌群的MIVC时检测并记录股直肌和股二头肌的表面肌电信号，并计算积分肌电图（iEMG）和协同收缩率等。结果：在MIVC状态下，膝伸展时，健侧股直肌的iEMG大于患侧，差异有显著性意义（P〈0．05）；健、患侧股二头肌的iEMG比较，差异无显著性意义（P〉0．05）。膝屈曲时，健侧股二头肌的iEMG大于患侧，差异有显著性意义（P〈0．05），患侧股直肌的iEMG大于健侧，差异有显著性意义（P〈0．05）。患侧膝屈曲的协同收缩率大于健侧，差异有显著性意义（P〈0．05），而患侧膝伸展的协同收缩率与健侧比较，差异无显著性意义（P〉0．05）。结论：脑卒中偏瘫患者膝关节痉挛以伸肌群为主，对膝关节屈肌群和伸肌群收缩的协调性训练，尤其在膝关节屈曲运动时，增强主动肌收缩，抑制拮抗肌的协同收缩，应是脑卒中患者下肢康复的重要目标。     

脑卒中患者步态周期各时相中下肢肌肉的表面肌电特点

目的探讨脑卒中患者下肢前后肌群在步态周期及其各分相中表面肌电(sEMG)信号的变化,以便有针对性地对脑卒中患者进行步态康复训练。方法 2018年1月至6月,采用Noraxon表面肌电无线采集系统记录20例脑卒中患者和20例健康对照者在自然行走过程中双下肢胫骨前肌(TA)、股直肌(RF)、腓肠肌内侧头(GM)和股二头肌(BF)的sEMG信号。结果健康受试者双下肢TA、RF、GM和BF的肌电活动随步态周期呈活动与静止周期性变化、双侧同名肌肉交替活动,而脑卒中患者双下肢相关肌肉肌电活动发生明显改变,且失去规律性。结论 sEMG能反映脑卒中患者步态相关肌肉受损情况,可用于指导步态康复训练。     

脑卒中患者不同强度随意运动时的sEMG反应特点

目的：观察不同强度静态及动态运动负荷对脑卒中患者四肢肌肉sEMG信号变化的影响,研究脑卒中患者四肢肌肉活动的表面肌电信号特征与其神经运动控制的关系。方法：24例脑卒中患者参加本项研究,采用患、健侧自身对照实验方法设计,采用上肢屈肘和下肢伸膝静态运动,以及肘关节和膝关节动态屈伸运动负荷试验,采集主动肌和拮抗肌的表面肌电信号,分析信号振幅和拮抗比值等sEMG信号活动特征。结果：最大用力收缩时,上、下肢患侧主动肌AEMG小于健侧,而拮抗比大于健侧;小强度静态运动负荷过程中,患侧上肢主动肌的AEMG略高于患侧,拮抗比明显大于健侧。患侧下肢股外侧肌（VL）、股直肌（RF）和股内侧肌（VM）的平均AEMG、?T标准化值大于健侧,拮抗比小于健侧;小强度动态运动负荷过程中,上肢患侧主动肌AEMG明显高于健侧。下肢患侧VL、RF和VM的AEMG均值具有增大趋势,但无明显差异。而患侧拮抗比明显小于健侧。结论：脑卒中患者由于高位神经元和运动控制功能受损,导致其患侧在最大随意收缩时运动单位募集能力下降,而在轻负荷运动时运动单位募集过度。     

膝前交叉韧带重建术后步态分析初步研究

目的观察膝前交叉韧带（ACL）重建术后的步态变化。方法用三维步态分析仪观察Lysholm评分100分、ACL重建术后1年的患者14例。测试步态周期中健侧和患侧的时间距离参数（步频、步长、步速、单腿支撑时间、摆动期、支撑期）、膝关节在预承重期和摆动期的最大屈曲度以及股四头肌的表面肌电平均波幅。结果健侧和息侧的时间距离参数和膝关节最大屈曲度差异均无统计学意义，并且各时间距离参数均在正常参考值范围内。两侧的股直肌和股外侧肌表面肌电平均波幅差异无统计学意义，而患侧股内侧肌平均波幅显著小于健侧（P〈0．05）。结论ACL重建术后1年且Lysholm评分达100分的患者，步行时步态基本恢复正常，但股内侧肌肌肉收缩活动仍低于健侧。     

半月板损伤患者膝周肌肉的表面肌电图分析

目的探讨半月板损伤对膝周肌肉功能的影响。方法 2017年2月至2018年2月,单侧半月板损伤患者22例,记录下蹲、站起和屈膝70°最大等长收缩时,健、患侧股外侧肌、股直肌、股内侧肌和股二头肌的表面肌电图。结果下蹲和站起时,患侧股外侧肌和股二头肌的平均肌电值显著低于健侧(t 3.945, Z 3.847, P 0.001),腘绳肌共同活动比率明显高于健侧(t 3.650, P 0.01)。在70°最大等长收缩时,患侧股外侧肌、股直肌、股内侧肌和股二头肌平均肌电值均明显小于健侧(t 2.907, Z=4.107, P 0.01)。结论 sEMG能定量评价半月板损伤患者不同运动状态下膝屈伸肌功能。半月板损伤患者患肢膝周肌肉功能下降,协调性异常,应在康复治疗过程中加以纠正。     

膝关节骨关节炎患者膝屈伸肌的表面肌电信号研究

目的 评价单侧膝关节骨关节炎（OA）患者在不同运动状态下的健、患侧膝屈伸肌的肌肉功能和协调活动差异，为临床制定康复方案提供依据。方法 用Noraxon Myosystem1200型表面肌电图仪对26例单侧膝关节骨关节炎患者的等长肌肉收缩功能和下蹲运动进行表面肌电信号的测试。结果 患侧股外侧肌和股二头肌在最大等长收缩和下蹲运动时的肌电振幅均值小于健侧（P〈0．05）。在最大等长收缩过程中，患侧的拮抗肌协同收缩率较健侧增高（P〈0．05）；在下蹲运动过程中，患侧的胭绳肌共同活动比率高于检测（P〈0．05）。结论 表面肌电图测试可用于量化评价膝OA患者在不同运动过程中肌肉功能。膝OA患肢在不同运动状态下均可能存在肌肉功能降低和肌力平衡异常。康复治疗不仅应重视股四头肌肌力增强而且应重视改善膝关节的肌力平衡。     

脑卒中患者四肢肌肉的表面肌电信号特征研究

目的：观察不同强度静态运动负荷对脑卒中患者四肢肌肉sEMG信号变化的影响，探讨脑卒中患者四肢肌肉活动的表面肌电信号特征。方法：15例脑卒中患者和15例正常人对照组参加本实验研究，利用静态运动负荷诱发上肢肘关节屈肌和下肢膝关节伸肌收缩，采用表面电极引导和记录肌电信号并进行线性时、频分析。结果：脑卒中患者患侧下肢股四头肌和上肢三角肌前部的AEMG和MPF均值明显小于健侧，运动负荷对各组观察肌肉MPF时间序列曲线斜率变化均无明显实验效应。结论：静态运动负荷条件下脑卒中患者患侧肌肉sEMG信号活动的振幅降低，频率下降。     

基于超声弹性成像技术评价的股四头肌神经入肌点针刺法对脑卒中肌痉挛干预效应的研究

目的 观察应用超声弹性成像技术评价股四头肌神经入肌点针刺法治疗脑卒中后痉挛性偏瘫患者的临床疗效。方法 选取脑卒中偏瘫后下肢痉挛患者44例,随机分为治疗组和对照组各22例,两组均给予相同的基础治疗,对照组采用传统的循经取穴针刺治疗,治疗组采用股四头肌神经入肌点针刺疗法。2组患者分别于治疗前与治疗4个疗程后采用改良Ashworth分级、临床痉挛指数（CSI）、Berg平衡量表（BBS）评定,同时以剪切波超声弹性成像技术检测对照组及病例组患者治疗前后下肢股外侧肌、股内侧肌、股直肌及股二头肌,记录并比较组织弹性图和杨氏模量值,对结果进行统计分析。结果：2组患者BBS的评分均较治疗前明显提高（P﹤0.01）,治疗组与对照组比较有统计学意义（P﹤0.05）,2组下肢改良Ashworth及CSI评分均较治疗前明显下降（P﹤0.01）,治疗组与对照组比较有统计学意义（P﹤0.05）;治疗前观察组患者患侧与正常对照组相应一侧下肢相关肌肉的杨氏模量比较有显著差异(均P<0.01),观察组患者患侧治疗后股外侧肌、股内侧肌、股直肌及股二头肌杨氏模量值比治疗前下降(均P<0.05),治疗组患侧下肢比对照组相应侧下肢下降的更明显(均P<0.01)。结论：股四头肌神经入肌点针刺法能够明显缓解脑卒中后偏瘫侧痉挛下肢的肌张力,提高脑卒中患者日常生活活动能力,其疗效优于传统针刺方法。     

健康青年下台阶时股内侧肌、股直肌和股外侧肌间的表面肌电变化

目的探讨健康青年下台阶时股内侧肌、股直肌及股外侧肌的肌肉收缩强度差异。方法 2016年,选取首都医科大学2015级30名健康在校大学生,将电极贴于优势侧股四头肌上,采集受试者下台阶过程中的股内侧肌、股直肌及股外侧肌的肌电信号。结果在下台阶过程中,股直肌的最大收缩幅值和平均收缩幅值显著小于股内侧肌和股外侧肌(P0.001);而股内侧肌和股外侧肌无显著性差异(P0.05)。结论健康青年在下台阶过程中股内侧肌及股外侧肌的活性显著高于股直肌;股内侧肌与股外侧肌协同收缩活性相当。     

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.