数值求解人体上肢两刚体系统

目的 简化人体上肢结构，建立两刚体系统动力学模型，并对其进行数值求解。方法 以卡尔登角为广义坐标，运用多刚体动力学理论，建立上肢的动力学方程；运用MATHEMATICA计算软件对方程进行正、反数值求解并进行了比较。结果 得到了上肢的两刚体动力学方程和数值解，对比计算结果表明，将已知运动带入方程求得的主动力作为已知力反求得的卡尔登角与已知运动的卡尔登角基本一致，而且在反解时会出现奇点。结论 运用MATHEMATICA计算软件求解复杂的上肢两刚体系统方程，相当方便，为免奇点出现，应在适当范围内进行求解，在误差允许的范围内，求得的解是可以接受的。     

Cortisol and testosterone concentrations in wheelchair athletes during submaximal wheelchair ergometry

It is yet unknown how upper body exercise combined with high ambient temperatures affects plasma testosterone and cortisol concentrations and furthermore, how these hormones respond to exercise in people suffering spinal cord injuries. The purpose of this study was to characterize plasma testosterone and cortisol responses to upper body exercise in wheelchair athletes (WA) compared to able-bodied individuals (AB) at two ambient temperatures. Four WA [mean age 36 (SEM 13) years, mean body mass 66.9 (SEM 11.8) kg, injury level T₇–T₁₁], matched with five AB [mean age 33.4 (SEM 8.9) years, mean body mass 72.5 (SEM 13.1) kg] exercised (cross-over design) for 20 min on a wheelchair ergometer (0.03 kg resistance · kg⁻¹ body mass) at 25 °C and 32 °C. Blood samples were obtained before (PRE), at min 10 (MID), and min 20 (END) of exercise. No differences were found between results obtained at 25 °C and 32 °C for any physiological variable studied and therefore these data were combined. Pre-exercise testosterone concentration was lower (P < 0.05) in WA [18.3 (SEM 0.9) nmol · l⁻¹] compared to AB [21.9 (SEM 3.6) nmol · l⁻¹], and increased PRE to END only in WA. Cortisol concentrations were similar between groups before and during exercise, despite higher rectal temperatures in WA compared to AB, at MID [37.21 (SEM  0.14) and 37.02 (SEM  0.08)°C, respectively] and END [37.36 (SEM 0.16) and 37.19 (SEM 0.10)°C, respectively]. Plasma norepinephrine responses were similar between groups. In conclusion, there were no differences in plasma cortisol concentrations, which may have been due to the low relative exercise intensities employed. The greater exercise response in WA for plasma testosterone should be confirmed on a larger population. It could have been the result of the lower plasma testosterone concentrations at rest in our group. Accepted: 4 September 2000     

Skeletal manifestations in Fryns syndrome

We report on a female baby with Fryns syndrome who died soon after birth. The patient had short limbs, coarse face, hypoplastic lungs, diaphragmatic hernia, and acral hypoplasia. Literature review disclosed varying degrees of skeletal manifestations in Fryns syndrome; short limbs may be a component of Fryns syndrome. © 1995 Wiley-Liss, Inc.     

Impedance plethysmography in human limbs

Electrode design and electrode positioning are important factors in blood flow measurements using impedance plethysmography. Optimal electrode type and accurate positioning will decrease measurement errors and improve the signal-to-noise-ratio. Disk electrodes were found to be superior to tape electrodes because of their better skin-electrode stability and because they prevent limb compression. The distance between current electrodes and potential electrodes should be greater than 2·3 R (disk electrodes) and 1·5 R (tape electrodes) to avoid the influence of the so-called diffusion resistance (R is the radius of the limb at the electrode site).     

The reproducibility of test contractions for calibration of electromyographic measurements

Summary The main purpose of this study was to evaluate the reproducibility of electromyographic (EMG) measurements and specifically to test a calibration procedure with submaximal test contractions. Bipolar surface electrodes (20 mm fixed distance) were repositioned by a tracing sheet on both trapezius muscles, halfway between acromion and processus prominens. Submaximal test contractions were performed by keeping both arms straight abducted 90° and forward flexed 10° for 15-s periods. The arm position could be precisely reproduced in the frontal plane, but deviated forwards by 4° in the horizontal plane, where the sensitivity of the EMG response to arm position was lowest. The electrodes were repositioned within a radius of 3 mm with a probability of 90%. Large deviations in the EMG response were found within this radius and a significant depression of the EMG response was recorded over the middle part of the muscle (the innervation zone?). This change in sensitivity of the EMG response with electrode position occurred in parallel for the test and maximal contractions. The total coefficient of variation was estimated to be 23% for recurrent EMG measurements using the calibration procedure described.     

Effects of spontaneously chosen crank rate variations on electromyographic responses in sub-maximal arm exercise in inexperienced subjects

The aim of the present study was to compare electromyographic responses during arm exercises with a crank rate chosen spontaneously (T_S) or set at 20% below or above (T_–20, T₊₂₀) the spontaneously chosen crank rate (SCCR). Ten male physical education students performed arm exercises with intensities ranging from 20% to 80% of maximal power. Muscular activity levels were analysed for the biceps brachii and the triceps brachii muscles using integrated rectified surface electromyography (iEMG). All values were presented as the mean and standard deviation. During T_S, the sum of iEMG for the two muscles studied was significantly (P<0.05) lower than during T₊₂₀ for each power output. No significant differences were observed in iEMG values between T_S and T_–20. The hypothesis that SCCR relates to a minimisation of muscle activation during an upper body exercise was not confirmed. Variations superior or inferior to a 20% increase of the iEMG responses do not influence it. Moreover, the selection of crank rates depends on the power output and the SCCR increased significantly (P<0.05) with increasing power output.     

Ventilatory and upper-airway resistance responses to upper-airway cooling and CO2 in anaesthetised rats

The effects of upper airway (UA) cool air and CO₂ on breathing and on laryngeal and supraglottic resistances were studied in anaesthetised rats breathing spontaneously through a tracheostomy. Warm, humidified air containing 0, 5 and 9–10% CO₂ and cool, room-humidity air were delivered at constant flow to either the isolated larynx to exit through a pharyngotomy or to the supraglottic UA to exit through the mouth and/or nose (nose open or sealed). Spontaneous tracheal airflow and UA airflows, temperatures and pressures were recorded. CO₂ had no effect on breathing but caused a slight increase in laryngeal resistance which was abolished by cutting the superior laryngeal nerves (SLN). Cool air caused a decrease in respiratory frequency and/or peak inspiratory flow when applied to the isolated larynx or to the supraglottic airway with the nose closed. These effects were abolished by SLN section. With the nose open, the ventilatory inhibition was not abolished by SLN section. Cool air also caused substantial decreases in laryngeal and supraglottic resistances which were attenuated by SLN section and which persisted following recurrent laryngeal nerve section. In conclusion, whilst UA cooling inhibits breathing and decreases UA resistances, UA CO₂ has minimal effects.     

互动式头针结合镜像疗法对脑卒中软瘫期上肢功能障碍的康复疗效

目的：探索脑卒中患者促进上肢运动功能恢复中头针与镜像疗法联合应用的临床价值。方法：选取株洲市中心医院2021年8月至2022年11月期间收治的60例脑卒中后上肢功能障碍患者,以随机分组的方式分为两组,每组30例。其中常规康复训练联合镜像治疗纳入对照组,在对照组基础上增加头针治疗纳入观察组。在治疗4周后,比较两组患者临床治疗有效性、Fugl–meyer运动功能评定量表（FMA）上肢部分评分以及Brunnstrom分期。结果：两组患者治疗后FMA评分均高于治疗前,且观察组患者治疗后FMA评分高于对照组,差异具有统计学意义（P<0.05）。观察组患者治疗后上肢Brunnstrom运动功能分期结果优于对照组,差异具有统计学意义（Z=–2.101,P <0.05）。观察组患者治疗后手Brunnstrom运动功能分期结果优于对照组,差异具有统计学意义（Z=–2.152,P <0.05）。结论：在恢复早期,头针、镜像疗法与常规康复训练有效结合,对脑卒中患者软瘫期上肢运动功能恢复具有积极作用。     

血府逐瘀汤预防上肢皮瓣术后血管危象的临床研究

〔摘 要〕 目的：观察血府逐瘀汤预防上肢皮瓣术后血管危象的临床疗效。 方法：选取 2022 年 1 月至 2023 年 1 月就诊于 赣州市南康区第一人民医院的 60 例行上肢皮瓣转移术的患者,采用简单数字随机法分为观察组和对照组,各 30 例。术后 对照组患者常规应用 “ 三抗 ” 治疗,观察组患者在 “ 三抗 ” 的基础上加服血府逐瘀汤剂,比较两组患者术后皮瓣的血运情 况、总体疗效。 结果：术后 3 d、7 d,观察组患者皮瓣肿胀程度优于对照组,差异具有统计学意义（Z 分别为 –2.28、–3.46, P ＜ 0.05）;术后 1 d、3 d、7 d,观察组患者毛细血管反应优于对照组,差异具有统计学意义（Z 分别为 –6.89、–6.29、–7.35, P ＜ 0.05）;观察组患者疗效优于对照组,差异具有统计学意义（Z = –3.44,P ＜ 0.05）。 结论：上肢皮瓣术后的患者在常 规 “ 三抗 ” 的基础上,加用血府逐瘀汤可有效减少血管危象的发生,提高皮瓣成活率。