闭环植入式神经刺激器的现状与发展趋势

闭环植入式神经刺激器能根据患者生理信号的变化自适应地调整刺激参数的特性,使其成为研究的热点,患者的临床需求推动其设计开发的进展。介绍3种闭环植入式神经刺激器的作用机制和刺激参数评估的理论研究以及临床应用现状,这3种闭环植入式神经刺激器分别为代表中枢神经、外周神经及脊髓神经的脑刺激器,迷走神经刺激器以及脊髓神经刺激器。概括分析闭环植入式神经刺激器研究应用中未解决的问题和发展趋势,即闭环植入式神经刺激器的作用机制仍需要深入研究,刺激参数评估的有效性需要进一步提高,应用于临床的系统有待继续完善。     

面向动物机器人的柔性埋入式神经刺激器研制EI北大核心

神经刺激器是动物机器人的核心组成部分,尽管动物机器人的控制效果受到多种因素的影响,但神经刺激器的性能对动物机器人的调控效果具有决定性作用。面向动物机器人,利用柔性印制电路板技术研制了埋入式神经刺激器,不仅实现了刺激器通过控制信号产生参数可调的双相电流脉冲,而且对其携带方式、材料以及尺寸等方面也进行了优化,克服了传统背负式以及头插式神经刺激器存在的隐蔽性差且易感染的缺点。刺激器的静态、离体及在体性能测试结果表明,该刺激器不仅具有精确的脉冲波形输出能力,而且重量轻、体积小,在实验室和室外空间环境中均具有良好的在体工作性能。该项研究对于动物机器人的应用具有较高现实意义。     

ZEP系列诱发电位／肌电图仪体感刺激器

作者介绍了ＺＥＰ系列诱发电位／肌电图仪体感刺激器的工作原理。该刺激器精确地实现了计算机对刺激频率、脉宽和强度的数字化控制，并对消除刺激器的交流干扰、实现安全隔离提供了很好的解决方法。     

ZEP系列诱发电位／肌慢图仪体感刺激器

作者介绍了ＸＥＰ系列诱发电位／肌电图仪体感刺激器的工作原理。该刺激器精确地实现了计算机对刺激频率、脉宽和强度的数字化控制，并对消除刺激器的交流干扰、实现安全隔离提供了很好的解决方法。     

用于磁刺激的圆形线圈的优化研究

以华科公司研发产品HKYJ-1型磁场刺激器为基础,建立磁刺激线圈的RLC模型,根据线圈峰值磁能指标对HKYJ-1型磁场刺激器磁头线圈的优化性进行讨论和评估.仿真结果证明HKYJ-1型磁场刺激器的磁刺激用圆形线圈所产生的峰值磁能与磁刺激治疗所需阈值磁能未能形成最优,线圈峰值磁能过大,其后果使线圈能耗过大,至使磁头发热过大,(与设备实际使用情况相符)最终导致刺激器工作有效性降低.根据研究结果本文提出了HKYJ-1型磁场刺激器的改进建议,提出了优化磁刺激用圆形线圈制作参数和结构参数的途径和方法,这样有效地提高华科HKYJ-1型磁场刺激器的医疗效率.     

用于动物实验的植入式神经刺激器

很多科学研究和临床应用的植入式刺激器,如心脏起搏器、骨骼肌肉刺激器等近年来得到了很大的发展。在神经科学研究中,对象通常为小型实验室动物,故对植入式刺激器的设计有特殊的要求。用于实验的植入式神经刺激器的设计要求刺激源在最大程度上满足植入式装置的需要,如尺寸小、可靠性高、安全和易于使用。笔者考虑了上述基本问题并提出了两种类型的刺激装置。由于电刺激仅能通过小电极和     

自制用于麻醉药品实验的电脉冲刺激器

自制用于麻醉药品实验的电脉冲刺激器江苏省人民医院高敬文，殷雷我院麻醉科为了研究麻醉药物对气道平滑肌张力的影响，需要一台电脉冲刺激器，输出电脉冲，刺激肌肉组织收缩。脉冲刺激器输出要求：频率１０～７０Ｈｚ，脉宽０．３～３ｍｓ，输出峰－峰值１０～６０Ｖ，且...     

用于刺激响应测量的味觉刺激器的开发

目前,已有数种临床诊断方法用于味觉障碍患者。但大多数是基于患者主诉,不适用于揭示心理性症状,也不利于推断伪装疾病。临床上亟待客观检查方法的出现。尽管诱发响应EEG或MEG已经被作为一种客观方法用于诊断其他感觉器官障碍,但要想将其用于味觉障碍的诊断,一个具有极小上升时间的味觉脉冲刺激器是必不可少的,同时确保该刺激器产生与触觉干扰无关的纯味觉刺激也是十分重要的。由于这种刺激器还没有达到可用的程度,故几乎没有这样的实验报导。作者研制了一种可以产生短上升时间(16.5ms)的味觉刺激器。为了评估这种刺激器的特性,通过以下…     

用于外周神经的干涉电流刺激器设计

设计了一种用于外周神经电刺激的干涉电流刺激器。该刺激器为两路电流输出,可以产生4种波形,每种波形的频率、幅度等参数可在上位机进行设置,频率分辨率为0.2 Hz,幅度分辨率为0.01 mA,时间分辨率为0.1 μs。该刺激器的特点在于可在刺激强度一定的条件下连续改变电流比,或在电流比一定的情况下连续改变刺激强度。上位机采用LabVIEW开发,下位机采用FPGA对3片DAC进行控制,DAC产生的波形信号经过隔离恒流源电路后施加到负载。经过测试,刺激器能够准确产生4种波形,电流偏差在2.6%以内,恒流效果良好。该刺激器体积小,操作简单,产生波形稳定,可以用于无损选择电刺激研究。     

听觉刺激器的研制

作者介绍一种用微机听觉诱发电位刺激器。该刺激器可以产生“喀呖”声，具有十二档刺激频率，四档刺激脉冲宽度，刺激强度最大１３２分贝，并具白噪声屏蔽。     

'Derivation of new reference tables for human heart weights in light of increasing body mass index'

As body weights and body mass indices have increased over time, we questioned the validity of correlating heart weight with body weight and whether tables from previous decades remain relevant. We investigated this by collecting details of heart weight, body weight, height, gender and age from 384 autopsy cases with no obvious heart or lung disease. Heart weights, body weights and heights showed a normal distribution for both genders. Heart weight correlated slightly better with body surface area than body weight and we present new reference charts derived from these data. The correlation between heart weight and body weight has changed little, despite increases in body weight and body mass index. As life expectancy is increasing, we investigated the effect of age on heart weight and demonstrated a small increase in heart weight relative to body surface area for both genders, in contrast to a previous study.     

Body dissatisfaction within couples: adding the social context to perceptions of self

Nineteen heterosexual couples completed questionnaires concerning their own and their partner's body size. Although women reported higher levels of body dissatisfaction, both men and women reported being dissatisfied with their body parts. Further, the results showed comparability within couples for ratings of the male partner's body size but consistent differences for ratings of the female partner's body size. In addition, both partners reported most dissatisfaction with the female partner's body size. It is suggested that a sexual partner's beliefs may play a greater role in the development of men's body dissatisfaction and that the female body may have become a legitimate source of criticism for both men and women. The implications for the social context on self-perception are discussed.     

Relationship between normal heart size and body indices in Korean

We provided a curve-fit equation to predict the normal heart weight (g) in Koreans by examining 422 autopsies (215 males and 207 females, from newborn to age 77 yr) who were relatively in good general condition. Heart weight was well correlated with body surface area (m2), body weight (kg), and body height (cm) but poorly with age in both sex. Heart weight progressively increased from birth to the earlier 3rd and 4th decades in male and female, respectively, and then gradually decreased; mean heart weight of all age group was greater in male than in female and significantly different from birth to 4th decade. In both sex, heart weight exponentially increased in accordance with the increase of body height, body weight, and body surface (in male, heart weight=0.00312 x body height(2.239), r2=0.750, p<0.0001; in female, heart weight=0.00443 x body height(2170), r2=0.781, p<0.0001; in male, heart weight=9.22 x body weight(0.853), r2=0.770, p<0.0001; in female, heart weight=9.00 x body weight0.855, r2=0.820, p<0.0001; in male, heart weight=155.18 x body surface area1.290, r=0.808, p<0.0001; in female, heart weight=124.13 x body surface area1.242, r=0.834, p<0.0001). These results indicate that heart weight is better correlated with body surface area than with body weight; however, body weight should be a better determinant of a predicted heart weight, since body surface area is entirely dependent on body height and body weight.     

Being,having, and becoming bodies

Following on from my earlier paper ‘Body psychotherapy and social theory,’ and continuing the argument that body psychotherapy has a lot to learn from contemporary social theories of embodiment, I describe what might be called the ‘cutting edge’ of those theories and suggest how this work might be applied to body psychotherapy. The crucial argument is that, although the crude Cartesian split between mind and body is clearly inadequate, it is a mistake to see body psychotherapy as trying simply to close the gap and unify mind and body. The experience of ‘having’ a body is intrinsic to human experience, and a necessary component of ‘becoming’ a body.     

Morphometric studies in inbred and hybrid house mice. VIII. Effects of litter size on brain size and body size.

Litter size, brain size, and body size were examined in inbred and hybrid house mice of three different ages in order to test whether litter size exhibits a positive genetic, but negative environmental association with both brain and body size. As estimated from among-line covariation, litter size showed a positive, but non-significant genetical association with brain and body size. It also showed a significant, negative environmental association with brain and body size, as hypothesized. Over all inbreds and hybrids, litter size explained 8% and 14%, respectively, of the within-strain (environmental) variation in brain and body size. It was concluded that the negative phenotypic association of litter size with brain size and especially body size is the reflection of a well-known negative maternal environmental effect whereby mice with large body sizes tend to produce larger litters of mice with smaller body sizes.     

人体核心温度的测量方法研究进展

体温是人体四大生命体征之一,成为人们判断人体健康与否的重要依据;保持恒定的体温,是保证新陈代谢和生命活动正常进行的必要条件。所以,人体温度是反映身体健康状况的晴雨表,有效地监测人体体温成为一个重要的话题。临床上所指的体温是指平均核心温度。在人们日常生活中,一般测量的是腋下、口腔和额头的温度,这些温度严格的意义上说的是体表温度,本身与核心温度存在一定的误差,况且又受周围环境、个人着装等多方面因素的干扰,所以并不能准确地代表人体核心体温。而人体核心温度才真正地和人类的新陈代谢更加关系紧密,所以急需一种高效、快捷的方法来实时地监测人体核心温度。针对该问题,分析总结国内外核心温度监测的研究现状,可以分为两大类:一是直接测量温度数据,在忽略一定误差的情况下,近似地以人体某一部位温度来代替人体核心温度;二是间接估算法,利用人体体表温度或者心率等一些生理数据,通过建模计算分析,推算出人体内部的实际温度。分析各方法的精确度,比较各方法的优缺点,并给出相应的结论。最后,预测核心温度监测方法将来的发展趋势。     

椎体内空隙形成的生物力学研究及其临床意义

目的 探讨椎体内空隙形成后的力学强度变化。方法 将新鲜单椎体标本通过其后正中的静脉孔，用刮勺制作椎体内空隙模型，再测其强度，并与邻近椎体强度进行比较。结果 显示当椎体内缺损分别占椎体体积的10％，20％，30％时，其强度减少的百分比分别为10.67%,18.00%,26．83％。结论 椎体内缺损可明显降低椎体强度，随着缺损的增大，椎体强度降低更加明显，当缺损超过一定大小时，日常活动的应力就可以造成骨折。     

Interface of data transmission for a transcutaneous communication system using the human body as transmission medium

We have been developing a new transcutaneous communication system (TCS) that uses the human body as an electrical conductive medium. We studied an interface circuit of the TCS in order to optimize the leading data current into the human body effectively. Two types of LC circuits were examined for the interface circuit, one was an LC series-parallel circuit, and the other was a parallel-connected LC circuit. The LC series-parallel circuit connected to the body could be tuned to a resonant frequency, and the frequency was determined by the values of an external inductor and an external capacitor. Permittivity of the body did not influence the electrical resonance. Connection of the LC series-parallel circuit to the body degraded the quality factor Q because of the conductivity of the body. However, the LC parallel-connected circuit when connected to the body did not indicate electrical resonance. The LC series-parallel circuit restricts a direct current and a low-frequency current to flow into the body; thus, it can prevent a patient from getting a shock. According to the above results, an LC series-parallel circuit is an optimum interface circuit between the TCS and the body for leading data current into the body effectively and safely.     

The prediction of total body water using bioelectrical impedance in children and adolescents

Total body water was measured in 26 children and adolescents using the stable isotope H2O18. Body resistance was measured using a tetrapolar technique with a constant 50Khz, 800 microA alternating current. Total body water was highly correlated (r = 0.97; P less than 0.001) with height2/body resistance. Measurements of body resistance are non-invasive, rapid and readily acceptable to children. For these reasons the measurement of body resistance requires further investigation, including cross validation studies and is a potentially valuable technique for assessing body composition in the paediatric population.