近红外光谱无创血糖测量的极限检测浓度研究

检测极限浓度综合了光子传输的微观过程信息、漫反射光的统计性质和仪器设备的系统性能,降低检测极限浓度是无创伤血糖浓度测量的目标所在。通过分析血糖浓度变化对光学参数的两种作用及其对光传播的影响,针对皮肤中葡萄糖主要分布真皮层的特点,引入有效信噪比的概念,推导了血糖检测极限浓度与光源检测器之间距离、有效仪器信噪比之间的关系。针对不同个体在表皮和真皮厚度的差异,用蒙特卡洛方法研究了其对检测极限浓度的影响,讨论了光学测头设计的方案和适应性。结果表明,通过选择合适的光源检测器之间距离,来自真皮层的有效信号能超过50%;假定仪器信噪比为10000,可获得满足FDA要求的血糖检测极限浓度。     

人体无创血糖检测的发展与现状

随着糖尿病的发病率逐年增高,为避免传统有创血糖监测血糖的痛苦,无创血糖监测已经越来越引起人们的重视。无创血糖检测技术就是在不对人体造成伤害的条件下检测人体血糖的方法。该方法可以避免传统试纸测试带来的痛苦,降低检测成本,提高病人测量的依从性,既能增加血糖检测的频率又能获得血糖的动态变化趋势,从而降低了患者糖尿病并发症的发生,同时可以避免针刺可能带来的感染,对于糖尿病人的自我监测具有非常重要的意义。详细介绍了当前各种无创血糖检测技术的原理,分析了各种技术的优缺点,并提供了国内外无创血糖仪的最新成果,还介绍了本人所在课题组所研发的基于代谢守恒原理的无创血糖监测产品。     

近红外无创血糖测量的研究

本文分析了光在手掌组织中的传播特性 ,以及经皮近红外无创血糖浓度测量原理。基于AOTF (声光可调谐滤波器 )分光系统 ,构建了近红外经皮无创血糖检测系统 ,并利用该系统对 3名健康青年志愿者进行OGTT (口服葡萄糖耐量试验 )实验 ,得到较好的测量结果。三次实验中PLS (偏最小二乘 )校正集模型的RMSEP (预测均方根误差 )分别为 0 6 9mmol/L、 0 4 9mmol. /L、 0 5 4mmol/L。     

近红外光谱在无创血糖监测中的应用

糖尿病患者的自我监测是减少由糖尿病引发的并发症的重要手段.现行的检测方法是有创的或微创的,给病人带来一定的痛苦,并且在使用中有许多不足.在几种光学的监测方法中,无创血糖监测的近红外光谱分析的方法是最具有应用前景的一种.在此介绍了国内外在这方面研究的进展情况、并且提出了一些看法.     

代谢热整合法无创血糖检测技术研究

介绍了一种新的基于代谢热整合法的无创血糖检测技术。采用温度传感器、红外传感器、湿度传感器和光学测量装置,通过测量人体代谢产生的热量、血液流速、血氧饱和度,利用人体代谢产生的热量是血糖浓度、供氧量的函数,可以推算出血糖浓度。介绍了系统的组成、数据处理方法及可能造成误差的因素。用所研制的检测系统进行了临床实验,得到的血糖值与用大型生化分析仪测得的血糖值的相关系数达到0.856。实验证明,代谢热整合法无创血糖检测技术是可行的。     

血糖无创检测光纤探测器设计

应用蒙特卡罗方法模拟了三层皮肤组织中光的传输和分布情况，模拟结果得出光经过皮肤组织漫反射后的出射位置分布和出射角度分布情况；根据此模拟结果，分析和设计了一种具有特殊结构的血糖无创检测光纤探测器，此探测器在表皮和收集光纤之间设置了一组反射镜面，大部分光经镜面反射后被收集光纤收集。此设计弥补了光纤数值孔径对探测器收集效率的限制。     

基于光声光谱法的无创血糖检测原理研究

利用光声光谱法无创血糖检测原理,以葡萄糖粉末和葡萄糖水溶液为样品、用调制激光作为信号激发源进行试验研究。可得到各个调制频率对应的光声信号幅值,进而得到光声信号幅值大小和调制频率的关系,最终找到葡萄糖粉末对应的最佳调制频率。在最佳调制频率下,测试葡萄糖水溶液,得到声信号随葡萄糖浓度增加的变化关系。实验不但找到葡萄糖对应的最佳调制频率,而且得到光声信号随葡萄糖浓度增加的线性关系,验证了光声光谱法在无创血糖检测中的可行性,为光声光谱法应用于无创血糖检测提供了一定参考价值。     

血糖检测方法研究最新进展

人体血糖浓度的检测对于糖尿病等疾病的诊断和治疗具有重大意义。本文按照美国糖尿病网血糖检测方法的分类标准，全面综述了目前血糖仪检测血糖，血糖无创检测和血糖连续监测等方面的最新进展情况。     

一种多信息融合无创血糖检测数据处理方法研究

以生物特征检测技术为基础,基于已经构建的无创血糖检测系统进行血糖检测数据分析。以光电检测技术为主,结合其他人体特征信息检测,对人体进行无创血糖测试得到大量数据,建立数学模型并利用算法来计算血糖浓度。与一种常用有创血糖仪检测数据进行对比,有创与无创检测结果的相关系数达到了85.4%,为多信息融合无创血糖检测系统提供了一种有效的数据处理方法。     

无创血糖检测仪温度标定系统的研制

血糖浓度是人体生理参数的一项重要生理指标,无创血糖检测仪能够实时检测血糖浓度。设计了一款针对于无创血糖检测仪的温度标定系统,以对称热传递法为基本方法,完成系统的软硬件设计。实验表明,系统能够完成对无创血糖检测仪的标定,标定后无创血糖检测仪温度参数测量误差为0.1摄氏度,满足仪器对相对精度的要求。     

传感器网络中人体感应智能节点的设计

针对传感器网络中人体存在的智能感知问题,文中设计了一种以ATmega16单片机为控制核心的热释电传感器感知节点,该节点能够准确地感应出半径3.5m、锥角110°范围内人体的存在,感知数据经单片机处理后传送到网络中的主机,通信接口采用无线和有线2种形式.节点采用主动和被动相结合的检测方式,组网时最多可在一个网络中接入256个节点.相对于电平和电流环传输方式的传感器,该感应节点在组网、扩展和某些布线不方便的场合更具可操作性.     

汽车车身夹具的设计要点、调试及发展

介绍了汽车车身夹具的设计要点,总结了夹具调试及验证的实用技术,最后提出了汽车夹具的发展方向.     

无创血氧饱和度的测量及无线监测系统的研制

随着光电子技术的快速发展,基于光电检测原理的血氧饱和度在线测量方法得到了广泛研究.以C8051F005单片机为处理核心的无创血氧饱和度测量仪,以nRF2401无线收发芯片构建一个无线监测平台,整个系统可以随时随地快速监测多个病人血氧饱和度的连续变化,极大地方便了社区和家庭的应用.     

新型微电极葡萄糖传感器

提出了一种新型的微电极葡萄糖传感器.以与IC兼容的硅作为基底材料,利用MEMS加工工艺,采用硅腐蚀及SU8微反应池方法制成了新型微电极传感器.与传统的电流型传感器相比,该传感器有较小的敏感面积(1mm×1mm),较低的检测下限(1×10-4M),较宽的检测范围(1×10-4～1×10-2M),较好的重现性与稳定性,以及易于与处理电路集成等优点.     

轿车车体装配尺寸偏差控制技术

基于偏差流理论,针对夹具的优化设计及鲁棒设计、柔性件装配偏差分析与综合、制造过程在线测量、故障诊断和偏差在线补偿,从设计和制造并行角度对车体偏差控制进行了系统综述,论述了面向设计和面向制造的偏差控制的辩证统一关系。结合所提出的偏差流库和偏差流检测站的概念,给出了偏差流控制的系统模型,丰富了偏差流理论。     

Dilemmas in Measurement of Human Body Temperature

Abstract

Measurement of human body temperature seems rather trivial until we become parents or medical professionals. If we use different thermometers, which are used at different body sites, inevitably we come across to different measurement results. Then we ask ourselves which result is the right one. The answer is far from trivial because there are a few dilemmas in measurement of human body temperature. To none of these dilemmas exists a straight answer. The article describes dilemmas in measurement of human body temperature and thermometers used for its measurement. Presented are also calibration results of certain clinical radiation thermometers and their improvement in the past few years in terms of accuracy and uncertainty.     

A Comparative Study of Landmine Detection Techniques

Several countries suffer from the existence of millions of buried landmines in their territories. These landmines have indefinite life, and may still cause horrific personal injuries and economic dislocation for decades after a war has finished. Therefore, there is a growing demand by these countries for reliable landmine inspection systems. There are several landmine detection techniques that can be used for this purpose. Each technique is suitable for detection under some conditions depending on the type of the landmine case, the explosive material, and the soil. This paper presents an overview of some of the existing landmine detection techniques. These techniques are briefly described and their merits and drawbacks are highlighted and compared. The purpose of this comparison is to shows the ideal conditions and the challenges for each technique. Furthermore, a comparison between landmine detection techniques from the points of view of cost, complexity, speed, safety, false alarm rate and effect of environmental conditions is presented.     

Novel Use of Scanning Electron Microscopy for Detection of Iron‐Induced Morphological Changes in Human Blood

Fibrinogen is key to the maintenance of hemostasis and is an acute phase protein that is part of the coagulation cascade of proteins. It plays a fundamental role in inflammation, particularly as indicator for a proinflammatory state and is a prominent marker for developing vascular inflammatory diseases. The ultrastructure of fibrin nets can be studied using scanning electron microscopy (SEM) with the addition of thrombin to plasma. In inflammatory conditions such as thromboembolic ischemic stroke and diabetes, the fibrin networks are changed to from dense matted fibrin deposits (DMDs) instead of typical netlike appearance. Similar DMDs can also be induced with the addition of FeCl₂ and FeCl₃. Importantly, the iron‐induced DMDs look similar to those from patients with prothrombotic conditions. Excessive or misplaced tissue iron now is recognized to pose a substantial health risk. The current research therefore investigates the establishment of a laboratory fibrinogen model to study that might mimic fibrin fiber generation that is achieved using plasma from healthy and diseased individuals. Furthermore, to determine whether the addition of iron to purified fibrinogen will show DMDs and whether hydrophilic agents can prevent them. We conclude that SEM is a very effective tool for the visualization of circulatory consequences of the interaction of iron‐induced hydroxyl radicals with human fibrinogen. Furthermore, this novel fibrinogen model provides a convenient method to study the interactions of the intramolecular and intermolecular hydrophobic forces responsible for the maintenance of the tertiary structure of native fibrin(ogen) and the prevention of iron‐induced DMDs formation by hydrophilic agents. Microsc. Res. Tech. 76:268–271, 2013. © 2012 Wiley Periodicals, Inc.