Suppression of spontaneous breathing during high-frequency jet ventilation

Conditions which suppress spontaneous breathing activity during high-frequency jet ventilation (HFJV) were analysed in Yorkshire piglets under pentobarbital anesthesia. The highest P_aCO₂ at which the animals did not breathe against the ventilator (apnea point) was established during different patterns of ventilation, either by changing the minute volume or by adding CO₂ to the inspiratory gas. Arterial oxygen tension was maintained throughout the study above 80 mm Hg. An elevation of ventilatory rate increased the apnea point, suggesting a progressive suppression of spontaneous breathing. This suppression did not depend on the amount of lung stretch during insufflation, because at higher rates lower tidal volumes were used. Suppression also appeared to be independent of insufflatory flow, i.e. the velocity of lung stretch. At higher frequencies end-expiratory airway pressure (P_EE) increased and there appeared to be a positive relationship between the apnea point and P_EE. In a separate series this positive relationship between the apnea point and P_EE was confirmed. A hysteresis effect in this relationship, however, suggests that other than jet frequency, lung volume rather than positive end-expiratory pressure (PEEP) is a major determinant of suppression of spontaneous breathing activity during HFJV.     

一种肌电控制假手的新型自适应增力机构

介绍一种用于肌电控制假手的新型自适应切换增力机构。对比现在国内外的各种假手增力机构，它不用超越离合器，因而更为简单、可靠、耐用。它不仅为广大的上肢残疾患者带来福音，也是康复器械上的一大革新     

Task-related differences in distribution of electromyographic activity within peroneus longus muscle of spontaneously moving cats

Summary In the hindlimb muscle peroneus longus (PerL) of cats, electromyographic activity (EMG) was recorded from anterior and posterior regions during voluntary motor behaviour. In spite of the fact that this muscle is composed of units that all exert their forces in the same direction, the intra-muscular EMG distribution differed in a marked and reproducible way between different types of motor behaviour. Anterior as well as posterior regions were both strongly active in relation to the swing-phase of stepping. In comparison to this stepping-activity, there was a marked predominance of posterior PerL activity during hindlimb standing (or take-off for a jump) and an equally pronounced predominance of anterior PerL activity when the cat was preparing to land from being lifted (or at the end of a jump). It is suggested that these task-associated differences in EMG distribution reflect topographical aspects of the intraspinal organization of motor tasks.     

EMG Biofeedback as a Tool for Simulating the Effects of Specific Leg Muscle Weakness on a Lifting Task

This study investigated the use of EMG biofeedback to simulate weakened rectus femorii and gastrocnemii muscles during the performance of a lifting task. Eight healthy women performed 15 kg free-style lifts from floor level. Three conditions were tested: unconstrained lifting, lifting with rectus femorii activity volitionally limited bilaterally through EMG biofeedback to less than 45% of maximal EMG activity, and lifting with the gastrocnemii limited to a similar level. Limiting leg muscle activity through biofeedback led to an alteration of lifting strategy, with resulting performance variables (joint angles and torques, angular velocities, center of pressure excursion, and segment coordination) comparing favorably with those from lifting trials performed by six women with moderate leg muscle weaknesses. The data indicate that EMG biofeedback can be used to simulate the effects of leg muscle weakness during these lifts, providing a new tool to study the biomechanics of muscle weakness.     

肌电图报告系统与Key Point肌电图仪连接的实现

介绍肌电图报告系统与Key Point肌电图仪连接的实现方法,报告的内容与形式及临床应用.     

膝骨关节炎患者肌电标准化方法的信度研究

目的 评估标准等长收缩(standard isometric contraction, SIC)与最大随意等长收缩(maximum voluntary isometric contraction, MVIC)应用于膝骨关节炎(knee osteoarthritis, KOA)患者肌电标准化的重测信度。方法 采用无线肌电测试系统收集KOA患者患侧腿在慢跑、SIC测试和MVIC测试时臀大肌、半腱肌、股直肌、股外侧肌、胫骨前肌、外侧腓肠肌和比目鱼肌的肌电数据。使用组内相关系数和95%置信区间评估重测信度。结果 KOA患者执行SIC测试时7块肌肉的重测信度均较好,执行MVIC测试时5块肌肉重测信度一般,2块肌肉重测信度较好,7块肌肉在SIC测试中的重测信度均高于MVIC测试;KOA患者慢跑时7块肌肉经SIC标准化后的重测信度均高于经MVIC标准化的重测信度,且股直肌经SIC标准化后的重测信度显著高于经MVIC标准化的重测信度。结论 对于KOA患者,SIC是一种比MVIC更为可靠的表面肌电标准化方案,具有较好的临床推广潜力。     

EMG诊断臂丛神经损伤的临床特征观察

目的 观察分析肌电图（EMG）诊断臂丛神经节前损伤的临床特征.方法 检测48例患者的三角肌、肱二头肌、伸指总肌、小指展肌、拇短展肌及腋神经、肌皮神经、桡神经、正中神经、尺神经,应用EMG仪测定支配肌肉的EMG及运动神经传导速度、感觉神经传导速度,对运动单位电位进行研究,并观察肌肉的自发电活动,同时测定神经的复合肌肉动作电位,计算出神经传导速度和潜伏期.结果 48例患者中,不完全损伤30例,完全损伤18例;根以下受损33例,根性受损15例.结论 EMG诊断对臂丛神经损伤的诊断、定位、定性分类都具有重要意义.     

基于AVR单片机的肌电信号生物反馈测试仪的设计

肌电信号(EMG)是一种伴随肌肉运动而产生的生物电信号,对表面EMG的分析研究可发现它与肌肉生理状态和肢体运动模式之间的对应关系。基于生物反馈技术研制肌电信号生物反馈仪采用AT-MEGA16 AVR单片机为核心元件,通过信号调理电路消除表面EMG工频干扰和噪声,并利用声光报警反馈肌肉紧张程度信息。本文介绍了肌电信号生物反馈仪的基本构成及其特点,并对肌电生物信号的特点和提取方法进行了分析,采用均方根值(RMS)法实时反映肌肉活动状态,试验结果表明本系统能有效缓解肌肉的紧张程度,在康复医学方面有较好的应用前景。     

脊髓型颈椎病与肌萎缩性侧束硬化的电生理对比研究

目的：探讨电生理检查对脊髓型颈椎病（CSM）与肌萎缩性侧束硬化（ALS）的签别诊断价值。方法：对124例其中52例脊髓型颈椎病和72例肌萎缩性侧束硬化症进行上、下肢肌、胸锁乳突肌肌电图检查,及C5～C8皮节体感诱发电位（DSEP）检查。结果：肌电图（EMG）检查脊髓型颈椎病上、下肢肌、胸锁乳突肌肌电图异常率分别为54％、8％、8％;肌萎缩性侧束硬化异常率分别为97％、89％、69％。DSEP检查脊髓型颈椎病异常率为92％;肌萎缩性侧束硬化异常率为l％,差异具有非常显著性意义（P〈0、001）。结论：选择上、下肢肌、胸锁乳突肌肌电图检查及C5-C8皮节体感诱发电位检查应作为两种病的常规电生理检查项目,可提高两种病的鉴别诊断率。