基于生物电阻抗法的人体成分测量系统的研究与评价

目的：本文探讨了生物电阻抗测量系统对人体成分的测量效果与适用性。从而为测量人体成分时选择合适的测量系统提供了技术支持与理论依据。方法：对生物电阻抗测量系统进行了深人的研究与评价,剖析总结了生物电阻抗法测量系统存在的问题,并对生物电阻抗法测量人体成分的影响因素进行了归纳与总结,最后对生物电阻抗法测量人体成分的未来发展进行了展望。结果：生物电阻抗法测量系统经历了从单频率全身测量系统到多频率人体分段电阻抗测量系统的发展过程,测量系统本身所具有的特性及外界因素都会对整个测量系统有一定干扰,所以针对不同的测量需要选择合适的测量系统与测量方案可以最大限度的减少干扰。结论：生物电阻抗法是测量人体成分的理想方法,生物电阻抗法测量系统的选择是人体成分测量的关键。随着研究推进,将会出现适用于人体局部的电阻抗测量系统。     

人体足底压力的测量与分析

人体足底压力的测量与分析张潇，卢世璧综述（中国人民解放军总医院）上世纪７０年代就有人开始研究人体足底的受力情况。以后各种测量足底压力的方法不断出现，测量技术不断改进，特别是近二十年，发展更为迅速。目前，这项研究已应用于很多领域，如生物力学，康复医学、…     

一种新的分段生物电阻抗评估人体成分方法的实现：人体参数相关性分析

用分段生物电阻抗方法评估人体成分需测量人体各段的长度或横面积,增加了这种方法的复杂性。本文通过分析人体参数间相关性,得到了用性别、身高、体重表示的各段参数的线性回归等式,从而简化了分段阻抗法。     

一种新的六电极人体阻抗测量方法

目前的阻抗分段测量方法是人体成分测量比较精确的办法,但这种测量方法比较复杂,费时较长而且电极费用较高。新方法只需人站在脚踏板上,双手抓住手握架,解决了上述问题,对二十四个人采用同一台阻抗测量仪用新方法与旧方法进行对比实验,结果一致性很好。     

人体头面部测量项目相关分析

目的：研究人头面部测量项目之间的内在关系。方法：利用宁夏回族群体体质调查资料,对人类头面部16项测量项目进行了相关分析。结果：（1）头长与头水平围、额最小宽、额最小宽、两眼外角宽、形态面高与容貌面高相关;（2）头水平围与头面部很多项目都相关;（3）头面部及五官的宽度项目彼此间密切相关,而与高度项目相关不显著;（4）头面部及五官的高度项目彼此间存在一定程度的相关。（5）头长与头宽之间、鼻高与鼻宽之间并不相关。结论：人类头面部测量项目间相关较为密切。与男性相比,女性头面部项目间相关更为多见。     

人体组成的活体测量技术及评价

人体组成的活体测量技术是人体组成学研究的重要内容,近年来有了长足的发展。我们概述了人体组成活体测量技术的现状,介绍了目前常用的测量方法,如人体测量法、代谢产物方法、密度测定法、稀释方法、总体钾法、中子活化分析法、生物电阻抗测定法、双能源X线吸收测定法、影像学方法和红外线干涉法等,并就这些技术的原理、方法、应用进行了简述。     

生物电阻抗分析法(BIA)测量人体成分

测量人体成分的理想方法应当是相对廉价的、病人易于接受的、可以由非专业人员来操作的、结果准确且可重复性高的。生物电阻抗分析法 ( BIA)可以部分满足这些要求。然而 ,生物电阻抗分析法 ( BIA)还有许多待解决的问题和应用的限制。本文综述 BIA的基本理论、数据分析方法。     

基于驾驶与车内操作设计的青年男性人体形态参数测量数据分析

通过大样本装甲车辆驾驶员或操作员等人群的人体参数测量与分析,得出典型尺寸间的拟合关系,为车辆产品或装备的设计、同类人群基础数据积累和更新、相关标准的修订提供依据。选定76项人体形态静态参数和11项功能参数,实测某现役装甲部队官兵1 243人。对测量数据进行统计分析,得出身高、坐高与相关数据的相关系数和拟合方程,并与GJB1835-1993中对应数据进行了对比。此次测量结果表明,人体铅垂轴方向尺寸与身高、坐高相关性显著,身体长度、围度和宽度方向的尺寸与同类人群相比均较上世纪80年代有明显增加。这与现有研究结果趋势一致。本次测量结果为中国青年男性人体形态基础数据的积累和更新、相关标准的修订和特定装备的设计提供了重要依据。     

人体间接测量方法初步研究

目的 研究人体间接测量的方法,为进行大规模的人体测量提供一种快速、简便和准确的新方法.方法 对身高、上肢长、下肢长、面宽、肩宽、髂前上棘间宽等6项指标进行活体直接测量和间接测量,并进行数据的统计分析.结果 6项指标的直接测量值和间接测量值之间均具有良好的相关关系(P＜0.001),回归系数的t检验提示回归系数有意义(P...     

人体脂肪测量新方法研究

本文是人体体能测量新方法研究课题的系列论文之一，它研究论证了我们改进的人体脂肪测量新方法的可行性，有效性和实用性，使用自己研制的人体体重脂肪测量仪（利用改进的脂肪测量新方法），日本欧姆龙公司的脂肪测量仪，Tanita脂肪测量仪，自制的水下称重系统和分段阻抗六电极脂肪测量仪做人体实验，实验对象为在校学员55人，年龄为19至21岁，男性40人，女性15人，对所做人体实验的数据进行分析，发现使用改进的脂肪测量新方法测量人体脂肪的结果和采用水下称重系统方法测量的结果相关性很好，相关系数为0．974（P＜0．01），脂肪测量新方法与其它人体成分测量方法相比，可以减少电极数目，操作简便，因此改进的脂肪测量新方法可以替代整体和分段阻抗测量法。     

生物电阻抗技术的医学运用

生物电阻抗技术在临床的检查和监护中已有一定的应用，它的优点是无创性、功能性，以及价格低，操作方便等，但也有定量性及定位性差等问题。本文就生物电阻抗技术在阻抗血流图、人体阻抗成像及人体成分测量等方面的研究进展进行了综述，并分析了生物电阻抗技术未来的发展趋势和方向。     

Assessment of body composition in the prader-willi syndrome using bioelectrical impedance

The accurate assessment of body composition is of importance in the Prader-Willi syndrome. Many techniques are not applicable due to ethical or practical reasons. However, the bioelectrical impedance technique is a rapid, painless, noninvasive method of estimating total body water and hence, fat-free mass in obese children and adolescents. We have compared estimates of total body water derived from bioelectrical impedance with actual measurements taken, using H₂¹⁸O dilution, in 14 children with Prader-Willi syndrome. Existing equations for predicting total body water from impedance showed a bias to underestimate actual measures of body water. There were positive correlations between the degree of underestimation with age and body fatness. It is possible that changes in body shapes influence bioelectrical impedance measurements in obese individuals, and that a prediction equation based upon a normal population will not be applicable to obese individuals. © 1992 Wiley-Liss, Inc.     

Comparison of three segmental multifrequency bioelectrical impedance techniques in healthy adults

Background: The analysis of segmental or limb bioimpedance has gained importance in human population biology. However, standardized measurement techniques are needed.

Aim: This study compared three techniques for segmental analysis (T1, conventional electrode measurement; T2, use of a novel additional switching unit; T3, equipotentials instead of switching unit) which are often used in population biology.

Subjects and methods: The techniques were compared in 124 healthy adults (19–83 years) using a tetrapolar bioimpedance analyser (Nutriguard-M) at multiple frequencies (5, 50, 100 kHz) to gain whole-body and segmental resistances, reactances and phase angles.

Results: Repeated measures ANOVA yielded a significant technique effect for most variables (26/27), a significant interaction technique × sex for half (13/27), and a significant interaction technique × age for a quarter (7/27) of variables.

Conclusions: Differences exist between the three techniques which are primarily caused by inconsistent current pathways. A comparison with literature data showed that, in addition, subject's posture during measurement, electrode contact and electrode site may lead to inconsistent resistance and reactance values. This makes comparisons between different populations difficult. Therefore, this study recommends generally using the T2 technique which is standardized, easy to use and, thereby, well suited for field studies in large population groups.     

体外人脑胶质瘤电阻抗特性及等效电路

目的 研究人脑胶质瘤的电阻抗特性并建立其等效电路,可为进一步区分人脑胶质瘤和正常脑组织的阻抗特性差异提供依据.方法 利用英国Solartron公司的阻抗分析仪（1260）,采用四端法,在10 Hz ～ 10 MHz范围内,对4例体外人胶质瘤组织进行电阻抗测量.通过分析其频率特性并结合已有的人脑组织的等效电路,建立了体外胶质瘤的等效电路,利用阻抗分析软件Z-VIEW对其进行仿真.结果 体外人脑胶质瘤的阻抗模值在10 Hz～10 MHz范围内随频率的增大而下降,相位角在该范围内随频率的增大而增大.体外人脑胶质瘤组织在10 kHz ～ 10 MHz范围内电阻抗实部比较稳定,其中在10Hz～ 10 kHz范围内,实部随频率的增大而减小.电阻抗虚部在20 kHz ～ 10 MHz范围内较稳定,而在10Hz ～ 20 kHz范围内,虚部随频率增大而增大.样本的等效电路仿真曲线与实际曲线相比较,等效电路模型能较好地反映体外人脑胶质瘤的电阻抗特性.结论 体外人脑胶质瘤与已知的正常脑组织的电阻抗特性及等效电路差别明显,这为探索生物电阻抗技术应用于区别胶质瘤与正常脑组织的临床应用提供了研究基础.     

A comparison of three bioelectrical impedance analyses for predicting lean body mass in a population with a large difference in muscularity

This study tested the hypothesis that, as compared to whole-body bioelectrical impedance (BI) analysis, segmental BI analysis can estimate lean body mass (LBM) more accurately in a population with a large difference in muscularity. In addition to whole-body BI, which determines impedance (Z) between the wrist and ankle, two segmental BI analyses which determine the Z value of every body segment in each of (1) the arms, legs and trunk (distal BI) and (2) the upper arms, upper legs and trunk (proximal BI) were applied to a group of 125 male athletes and 75 non-athletes. The subjects were divided into validation and cross-validation groups. Simple and multiple regression analyses were applied to (length)²/Z (BI index) values for the whole-body and each body segment, to develop the prediction equations of LBM measured using air-displacement plethysmography. In the validation group, the SE of estimation was similar in the whole-body (3.4 kg, 5.4%), distal (3.4 kg, 5.5%) and proximal BI (3.3 kg, 5.2%) analyses. However, the whole-body and distal BI analyses produced systematical errors in the estimates of LBM. Moreover, the residuals in the two methods significantly (P<0.05) correlated with the ratios of BI indices of the upper arms and upper legs to those of the arms and legs, respectively, calculated as variables approximating the relative development of lean tissues at the proximal area of limbs. On the other hand, the proximal BI analysis was validated and cross-validated. Thus, the accuracy of estimating LBM was similar in the whole-body and the two segmental BI analyses. However, the prediction equations derived from the use of the whole-body BI index and a combination of the arms, legs and trunk BI indices produced a systematical error relating to the difference between the limb segments in lean tissue development.     

Standardisation of bioelectrical impedance analysis for the estimation of body composition in healthy paediatric populations: a systematic review

Background: Bioelectrical impedance analysis (BIA) requires a high degree of standardisation in order to ensure valid and reproducible impedance measurements. The overall aim of this review was to study the degree to which BIA papers conducted in healthy paediatric populations (aged 0–17 years) were standardised.

Methods: Literature was identified on the basis of a systematic search of internationally-recognised electronic databases and hand searching of the reference lists of the included papers in order to identify additional relevant papers. The review was limited to lead-type BIA devices for whole-body, segmental- and focal impedance measurements. In total, 71 papers published between 1988 and 2016 were included.

To evaluate the degree of standardisation of the papers, a recently published review detailing critical factors that may impact on BIA measurements in children was used as a model for structuring and extracting data.

Results: There was a general lack of BIA standardisation, or its reporting, in the papers under review, which hinders comparison of data between studies and could potentially lead to erroneous measurements.

Conclusions: If the BIA technique should be accepted clinically for routine use in paediatric populations, there is a need for an increased focus on the importance of improved standardisation and its reporting in future studies. Consequently, this review contains recommendations for performing and reporting BIA measurements in a standardised manner.     

Dependence of biomechanical impedance upon living body structure

A physical model for biomechanical impedance has already been proposed. This model is characterised by three impedance spectra: soft, intermediate and hard pattern. An impedance spectrum of the body surface represents mostly the soft pattern, The formative mechanisms of all three patterns have been unsolved until now. Because the physical model is expressed by experimental equations, its theoretical background is not apparent. In the paper a simulating material (simulator) is used, whose tactility is not unlike human skin, and the formative mechanism of biomechanical impedance is revealed through experiments on the simulator under various measuring conditions. The influences of the measuring circumstances, living body structure and physical constants of the body tissues on the experimental equations of the physical model are fully discussed. The formative mechanism of biomechanical impedance which represents the physical model is explained in terms of an equivalent mass, a dynamic equivalent stiffness, a dynamic viscosity and a composite characteristic. The dependence between body parts from which the measurements are taken and soft, intermediate and hard patterns are demonstrated.