Levodopa improves physical fatigue in Parkinson's disease: a double-blind, placebo-controlled, crossover study.

We quantitatively investigated the effect of carbidopa/levodopa (25/100) on physical fatigue during finger tapping and force generation in a double-blind, placebo-controlled crossover study. Parkinson's disease (PD) subjects were randomly assigned to carbidopa/levodopa or placebo for Visit 1 or 2 and participated in the following two studies: (1) Finger tapping. Twenty-five PD patients used their index fingers to strike two keys 20 cm apart on a musical instrument digital interface (MIDI) keyboard. The slopes of the regression line of dwell time and movement time were used to assess the rate of fatigue development. (2) Force generation. Twelve PD patients contracted the wrist extensors maximally to obtain a baseline maximum voluntary contraction (BMVC) force. Then they repetitively contracted the wrist extensors at 50% of the BMVC for 7 seconds and rested for 3 seconds. An interval maximum voluntary contraction (IMVC) was measured every three repetitions. Fatigue was defined as an IMVC of less than 60% of the BMVC. The slope of the regression line of IMVC was used to assess the rate of force decline. These two studies were repeated 1 hour after carbidopa/levodopa (25/100) or placebo. Subjects filled out the Multidimensional Fatigue Inventory (MFI) at the beginning of the first visit. Results showed that the slope of dwell time decreased with levodopa but not with placebo (P = 0.004). The rate of force decline also decreased with levodopa but not with placebo (P = 0.01). The subscores in the dimension of physical fatigue in the MFI did not correlate with the rate changes in dwell time or the rate changes in force decline. We concluded that (1) levodopa improves physical fatigue in finger tapping and force generation, (2) physical fatigue in Parkinson's disease is at least partially related to dopamine deficiency, and (3) the MFI measures different aspects of physical fatigue compared with those measured by finger tapping and force generation.     

用磨牙作支柱拉尖牙向远中支柱情况的早期观察

选择６２例拔除第一双尖牙的样本，分为平弓丝组、带“Ｕ”型阻滞曲组、固定舌弓组，采用方丝弓细丝弓技术，以磨牙作支抗拉尖牙向远中移动，对支抗磨牙进行观察。为期４周的观察发现，平弓丝组、带“Ｕ”型阻滞曲组的支抗磨牙均有近中舌向扭转，第二双尖牙中央窝间距亦比治疗前减少；而固定舌弓组支抗磨牙未见有近中舌向扭转。作者认为：以磨牙为支抗移动尖牙时，应注意支抗控制。本文对力的使用及支抗失控的预防、处理问题进行了讨论。     

骨骼肌最大收缩力与最适初长度及其参数的研究

本实验以免载体股直肌为实验模型,研究了该肌在一定脉冲电流刺激下其初长度与收缩力、肌张力及肌力变化的相互关系。同时测定了正常生理状态下兔伸屈膝时股直肌拉长度的变化。结果表明:兔股直肌延长在1.0cm内时,肌力随初长度的延长而增大,超过1.0cm时增大已不明显(p<0.0 1),1.0cm与股直肌的生理最大延长度1.1cm相似。说明兔股直肌的初长度变化不应超过生理最大延长度。而人的骨骼肌与哺乳动物的骨骼肌没有本质的区别,因此,人骨骼肌的初长度变化也不应超过生理最大延长度。肌腱转位后的活动范围应在原位的生理活动范围内,才能发挥最佳收缩效应。     

The acceleration transducer – an assessment of its precision in comparison with a force displacement transducer

A new and simple acceleration transducer (ACT)–based system of neuromuscular monitoring has recently been introduced. The precision of this transducer has been evaluated as compared to a conventional force displacement transducer (FDT) in the present study. Ten progressions of spontaneous recovery from atracurium–induced block with simultaneous measurements using the ACT on one hand and the FDT on the other were studied. Five individuals undergoing elective surgery in modified neurolept anaesthesia and one ICU–patient requiring prolonged neuromuscular blockade, sedated with pentobarbital, were included. Measurements were carried out on the latter patient on 5 consecutive days. Train–of–four (TOF) stimulation was used, readings were given in twitch heights (TH) (Tl/control value), and when four responses were obtained in TOF–ratios (T4/T1). Linearity was achieved after logit–transformation and the values regressed on time for each progression of recovery. Analysis of variance was applied to the regressions for the TH and TOF–ratio readings of each transducer. No significant differences were found, either between variation due to differences between slopes or variation due to technical error between the two transducers. The study indicates that the ACT is equal to the FDT with regard to precision in clinical recordings on atracuriumrelaxed individuals.     

鲁格氏棒横突固定法的实验研究和临床应用

取10具新鲜成年雄性家猪的脊柱标本,分两组观察鲁格氏棒经椎管行椎板固定和鲁格氏棒经横突椎板固定时,受破坏性屈曲力的数据,结果显示鲁格氏棒经椎管固定组在达1048.6（±20）N时,所固定的椎板发生骨折,部分钢丝断裂;鲁格氏棒经横突固定组达2058（±20）N时,仅发生棒弯曲,未发现任何部位骨折或钢丝断裂。临床治疗33例不稳定胸腰椎骨折脱位患者,术后X线片示骨折脱位复位满意,两周后患者可离床活动,随访2～2.5年未发现任何并发症。     

等剪切场中剪切率与剪切时间对全血血小板自发聚集性的影响

本文在研究等剪切场中剪切率与剪切时间对全血血小板自发聚集性的影响时发现,随着剪切时间的延长,血小板自发聚集率与剪切率的关系逐渐由正相关转化为负相关;而随着剪切率的增加,血小板自发聚集率与剪切时间的关系也由正相关转为负相关;剪切率在46 S~(-1)或剪切时间在20分钟时,血小板的自发聚集率与剪切时间或剪切率无关。     

Oral function in patients wearing fixed prosthesis on osseointegrated implants in the maxilla: 3-year follow-up study

Seventeen consecutive selected patients rehabilitated by means of a full maxillary bridge on osseointegrated implants ad modem Brånemark were evaluated over a 3-yr period. Besides a subjective evaluation by means of a questionnaire an examination of the occlusal relationship, chewing force, chewing efficiency and interocclusal threshold level was performed before, immediately after, 3–6 months after, and finally 3 yr after bridge installation. All subjects were very pleased with the oral rehabilitation. The chewing force and the chewing efficiency development increased over time, while the threshold level for interocclusal detection remained unchanged. The clinical dysfunction index according to Helkimo indicated that there was no marked change in signs of dysfunction of the patients' masticatory systems during the observation period. From the present longitudinal investigation one can conclude that the replacement of a full maxillary denture with a fixed prosthesis on osseointegrated implants, facing a natural dentition or an osseointegrated implant supported bridge in the opposite jaw, leads to a progressive increase of chewing efficiency and chewing force, and a constant subjective improvement of jaw function, while no masticatory dysfunction seems to occur during the observation period.     

Mechanobiology and force transduction in scars developed in darker skin types

BACKGROUND: Scarring is a complex process involving many cell types, cytokines and biological pathways including mechanobiology. Some subtle mechanical properties of skin can be assessed by measuring the speed of ultrasound shear wave propagation. The orientation of abnormal skin tension forces can be visualized, particularly in darker skin types, using dermoscopy showing distinct patterns of rete ridges' conformation. AIM: To assess some mechanobiological features of scars in darker skin types. PATIENTS AND METHODS: Large atrophic and hypertrophic surgical scars were examined on the trunk of 35 darker skin subjects. The surrounding skin was used as a comparator. Dermoscopic aspects were recorded. Resonance running time measurements (RRTM) were performed using a shear wave propagation device (Reviscometer). They were performed in four specific directions at given angles with regard to the long axis of the scar. The minimum, maximum and mean RRTM values were recorded at each site. RESULTS: Dermoscopy revealed patterns of melanin deposits in scars distinct from the normal honeycomb network seen in the surrounding skin. Hypertrophic scars showed a patchy pattern of large macular melanoderma dispersed in a lighter background. In these cases, low RRTM values were obtained with little variations according to the orientation of the measurements. By contrast, atrophic scars showed a streaky laddering melanotic pattern under dermoscopy. Higher RRTM values were often obtained, particularly in the transversal direction of the scars. Mechanical anisotropy was greater in the atrophic scars compared with the normal skin. DISCUSSION: Darker skin types represent a model for visualizing the main orientation of the epidermal rete ridges. A correlation was found between the pattern of melanized rete ridges of scars and the main orientation of the intrinsic forces in the skin.     

Relationship between plantar pressure distribution under the foot and insole comfort

In this paper, four pairs of insoles with different comfort characteristics were used to investigate the relationship between the pressure distribution under the foot and running shoe comfort. Fourteen male subjects were tested in four insole conditions by walking and running on a treadmill. The pressure at the plantar surface of the foot was measured by using an EMED pressure-measuring insole. For walking there were significantly higher pressures and forces in the midfoot area and significantly lower pressures in the medial forefoot and hallux area by wearing the most comfortable insole compared with wearing the least comfortable insole. The shift of the pressure from forefoot to midfoot for the most comfortable insole provided an even distribution of the pressure at the plantar surface of the foot. The results also demonstrated that the path of centre of force at the plantar surface of the foot moved to the lateral aspect of the foot for the most comfortable insole. For running, only the pressure in the medial forefoot area was found significantly lower for the most comfortable insole than for the least comfortable insole. The results of this study indicated that the pressure distribution between the plantar surface of the foot and the shoe could detect the change of shoe comfort. Thus it is a suggestion that pressure measurement may be related to understand factors important for shoe comfort.

Comfort of sport shoes is important for the appropriate execution of sport activities. Additionally, comfort may influence fatigue and possibly the development of injuries. The quantification of comfort of sport shoes and the understanding of mechanical and/or biological functions related to it may be enhanced with the use of pressure measurements between the plantar surface of the foot and the shoe sole.     

某特种兵大队新兵下肢军事训练伤情况调查

[目的]了解某特种兵部队新兵在入伍基础军事训练中发生的各种下肢训练伤的特点,为部队制定相应的预防措施提供科学依据。[方法]调查了该部队2006年度281名新兵的入伍训练情况(1~3个月),设计训练伤调查表,通过问卷调查了解训练伤发病情况,并进行分类调查统计。[结果]该部队2006年度入伍新兵在基础军事训练中发生下肢损伤75人,发生率为26.69%,发生下肢伤75人中,以小腿部位损伤最多,共35例,占下肢损伤的46.67%。踝关节损伤17例,占22.67%。足部损伤11例,占14.67%。下肢伤中急性损伤为20例,占26.67%,过劳性损伤55例,占73.33%。下肢损伤中骨与关节损伤38例,占50.67%,软组织损伤37例,占49.33%。损伤的原因:场地等外部环境因素18人次,训练负荷过大61人次,损伤所发生的训练项目:大部分为3 km跑,达64人次。[结论]下肢运动损伤是军事训练的常见病和多发病,其发病特点和发生规律各不相同且相当复杂。在该调查中,训练负荷过大所导致的软组织过劳性损伤最为重要。因此,在平常的军事训练中,应该加强健康宣教工作,在新兵训练过程中要注意战士的身体承受情况,循序渐进,减少下肢训练伤的发生。