The age-related changes of trunk responses to Achilles tendon vibration

The contribution of different sensory modalities to balance control is modified by age. Postural responses to Achilles tendon vibration were investigated in order to understand the influence of age on proprioceptive input from lower legs in human stance. Postural responses to bilateral vibrations of Achilles tendon with 10 s duration were recorded at three frequencies (40, 60 and 80 Hz) in 9 healthy young (range, 24–27 years) and in 9 healthy older adults (59–70 years). Subjects were instructed to keep standing on firm surface with eyes closed. They performed three trials in each of three vibration frequencies. Postural responses were characterized by displacement of the centre of foot pressure (CoP) and by kinematics of body segments in the anterior–posterior direction. Bilateral vibrations of Achilles tendon induced backward body lean increasing with frequency of vibration and with age. The leg angle response to vibration was found similar in both groups of subjects. Slight trunk tilts from vertical position were induced by vibration in young subjects while in older subjects the trunk tilted backward together with the whole body. This observation was supported also by the minimal change of hip angle in older subjects contrary to increased hip activity in young subjects. The findings showed that the trunk and hip angle responses to proprioceptive stimulation might be a good indicator of age-related destabilization in balance control.     

振动对动物体内血脂水平的影响

为了研究振动对生物体内物质的耗散作用，本文在振动频率为２０Ｈｚ，振幅为０．１ｃｍ条件下对土母鸡的腹部脂肪作局部振动。并于振动一个疗程（２小时／天，５－７ｘ）的前后分别测试了血清中总胆固醇（ＴＣ）、甘油三脂（ＴＧ）和高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）等各项指标。结果表明：上述特定频率、振幅与时间的振动使实验动物体内血清中总胆固醇、高密度脂蛋白胆固时与低密度脂蛋白胆固醇（ＬＤＬ－Ｃ）显著增加；甘油三酯显著减少（Ｐ＜０．０５）。ＴＣ的变化与ＨＤＬ－Ｃ、ＬＤＬ－Ｃ的变化呈正相关；ＴＧ的变化与ＨＤＬ－Ｃ的变化呈负相关。从而证实了特定参数的振动对动物体内的脂肪代谢有明显的作用，为人体施局部伍振动减肥的可行性提供了有益的参考。     

振动减肥中腹壁脂肪的超声检测与力学特征

本文是在研究振动对生物体内物质的耗散作用的基础上，试图利用振动对动物腹壁脂肪进行减脂的探索。通过实验，证实了利用趋声作为手段，可以对动物体内的腹壁脂肪作无创伤活体测量，其误差仅在１０％左右。使用振动对脂肪块得出了疲劳曲线和振动在生物体内传播的衰减曲线。对新鲜离体脂肪块所作振动模拟实验，证明在所使用的频率和振幅的振动作用下，能够迅速使脂肪的厚度消减，根据初步观察，在振动过程中有甘油从脂肪块中溢出，其消减体积的百分之八十为甘油成份，可以认为振动能促使脂肪细胞膜破裂或促使脂肪细胞内的脂滴水解，因此振动有可能成为减肥治疗方案中的一个重要措施。     

一氧化氮合酶阻断剂对豚鼠耳蜗基底膜振动速度的影响

目的：观察Ｎ－甲基－左旋精氨酸（ＮＮＡ）对基底膜振动速度（ＢＭＶ）的影响,了解一氧化氮（ＮＯ）对耳蜗外毛细胞（ＣＯＨＣｓ）的作用。方法：杂色豚鼠２５只,麻醉、手术准备后用１．６ｍｍｏｌ／Ｌ的Ｌ－ＮＮＡ８μＬ行耳蜗底圈鼓阶内灌注,测试ＢＭＶ、听神经复合动作电位（ｃＡＰ）、蜗内电位（ＥＰ）,记录用直流电脉冲诱发的ＢＭＶ。结果：蜗内灌注Ｌ－ＮＮＡ后,ＢＭＶ大约提高了３倍,耳蜗微音器电位振幅略有下降,而Ｅ     

一种基于微处理器的消化道内按摩装置的研制

首先简要回顾了微电子机械系统技术研究进展,然后介绍了一种基于微处理器的消化道内按摩装置的基本结构,工作原理和特点。尤其详细介绍了采用MSP430F123微处理器产生周期脉冲,来控制整个按摩胶囊的供电。总的说来,消化道内按摩装置具有重要的临床应用价值和商业价值,开发消化道内按摩装置对我国生物医学工程产业和微电子机械系统产业的发展都有着积极和深远的意义。     

Effect of Achilles tendon vibration on postural orientation

Vibration applied to the Achilles tendon is well known to induce in freely standing subjects a backward body displacement and in restrained subjects an illusory forward body tilt. The purpose of the present experiment was to evaluate the effect of Achilles tendon vibration (90Hz) on postural orientation in subjects free of equilibrium constraints. Subjects (n=12) were strapped on a backboard that could be rotated in the antero-posterior direction with the axis of rotation at the level of the ankles. They stood on a rigid horizontal floor with the soles of their feet parallel to the ground. They were initially positioned 7 degrees backward or forward or vertical and were required to adjust their body (the backboard) to the vertical orientation via a joystick. Firstly, results showed that in response to Achilles tendon vibration, subjects adjusted their body backward compared to the condition without vibration. This backward body adjustment likely cancel the appearance of an illusory forward body tilt. It was also observed that the vibratory stimulus applied to the Achilles tendon elicited in restrained standing subjects an increased EMG activity in both the gastrocnemius lateralis and the soleus muscles. Secondly, this vibration effect was more pronounced when passive displacement during the adjustment phase was congruent with the simulated elongation of calf muscles. These results indicated that the perception of body orientation is coherent with the postural response classically observed in freely standing subjects although the relationship between these two responses remains to be elucidated.     

应力式振动对下肢肌力、骨密度、抗骨折能力及体成分的影响

[目的]探讨应力式振动治疗对骨质疏松的防治作用以及对体成分的影响。[方法]前瞻、开放性、随机对照研究,研究对象为符合入、排标准者178人,其中女性118名,男性60名,分为治疗组和空白对照组,治疗组使用振动治疗仪给予频率(32±3)Hz,加速度0.5～2.94m/s2的振动,每次10min,每周3次(隔日1次),共12周。主要观察指标:第2～4腰椎骨密度、左侧股骨颈骨密度、左下肢肌肉分布系数、左下肢肌肉力量,左侧股骨颈抗骨折能力、体重指数、体脂百分比、全身脂肪分布。[结果]治疗组与对照组比较,左侧股骨颈骨密度、左下肢肌肉力量,左侧股骨颈抗骨折能力均上升,差异有统计学意义(P﹤0.001),其余各项指标的变化差异无统计学意义(P﹥0.05)。[结论]应力式振动可有效防治下肢骨质疏松,对体成分无明显影响。     

FMRI mapping of the somatosensory cortex with vibratory stimuli. Is there a dependency on stimulus frequency?

Vibratory stimuli on the skin are mediated by two major receptors: Meissner corpuscles and Pacinian corpuscles. These receptors differ in properties such as density distribution, receptive field size, frequency sensitivity and depth of location. The cortical response to stimulation of these corpuscles can be tested by taking advantage of the differences in frequency discrimination of the receptors. Meissner corpuscles are most sensitive to frequencies around 10-50 Hz (flutter), while Pacinian corpuscles are most sensitive to high frequency (100-300 Hz) vibration. This study compared the neuronal responses (hemodynamic response) generated from vibratory stimuli of 35 Hz and 150 Hz with functional MRI. Group functional activation maps showed differences in the activation pattern for the two stimulus frequencies.     

振动对小鼠体内磺胺嘧啶（SD）分布的影响

为了研究振动对生物体内物质的耗散作用，本文用药代动力学的方法在振动频率为２０Ｈｚ，加速度为１．１ｇ与５０Ｈｚ，４．４ｇ的条件下分别测试了小鼠体内血、肝与肾组织中磺胺啮咬（ＳＤ）在１至９小时内的分布，结果表明：２０Ｈｚ实验组血中ＳＤ浓度峰伍比对照组提前３小时，在振动１小时时，小鼠体内血、肝与肾组织中ＳＤ含量均比对照组高，但振动３小时至９小时内，其含量均比对照组低，从管道气栓体外模拟实验与本文的研究可得到启示：在上述频率与强度条件下，振动对生物体可能有促进血液循环的作用。     

Interaction of ultrasound and amniotic liquid

The ultrasonic properties (velocity at 2·81 and 5·04 MHz, absorption in the range 1–15 MHz and vibration potential at 200 kHz) of amniotic liquid have been investigated. The results indicate that at physiological pH the absorption is essentially due to the proteins found in amniotic liquid, its vibration potential to the sodium chloride contained in this fluid while the velocity appears to be determined both by the proteins and sodium chloride. In the acid range (pH ～ 3) and alkaline range (pH ～ 9·6), proton transfer processes involving a low molecular weight component of amniotic liquid, in addition to those involving the proteins, contribute to the absorption of ultrasound by amniotic liquid.