生物组织复阻抗谱测量系统设计及实现

目的：设计、实现用于测量生物组织复阻抗谱的系统。方法：系统采用频率响应测量原理和四电极法。结果：实现了生物组织复阻抗谱的测量系统，设计了用于测量软组织、液体组织测量的阻抗测量盒，以及在体组织测量的探头；利用这一系统进行了部分动物组织复阻抗谱的测量。结论：建立的生物组织电阻抗谱测量的一套完整方法。能精确测量动物组织在100Hz～10MHz频段内的复阻抗谱。     

微机极谱溶出分析法在卫生检验领域中的应用

极谱仪在 2 0年代已发明 ,由于受科学技术的限制 ,特别是受电子芯片技术限制 ,不能成熟地应用极谱分析技术 ,一段时间内有被淘汰的趋势。随着集成电路和芯片技术的发展 ,极谱仪也发生了革命性的突破。先是单板机示波极谱仪的问世 ,接着是单板机微机化极谱仪的改进 ,以至这几年发展到完全微机化的极谱溶出仪。微机化极谱溶出仪具有多功能、自动化、智能化、汉字化的电化学分析仪器。是以测定电解过程中的电流 -电压曲线 (伏安曲线 )为基础的一大类电化学分析方法。微机化极谱溶出仪是通用分析仪器 ,不受行业和样品种类的限制 ,是由所要分析的…     

现代极谱分析法在卫生监测检验中的应用与探讨

自 192 9年 ,捷克斯洛伐克的海洛夫斯基等人发现极谱波 ,并在 192 9年与日本工程师合作生产出第一台极谱仪后 ,众多的电化学工作者对其进行机理探讨和理论研究 ,逐渐形成了经典的极谱分析法 ,海洛夫斯基本人也获得诺贝尔奖。 195 8年海洛夫斯基被邀请到中国多个城市讲学 ,从此引发了我国大量的物理分析工作者的跟进性研究 ,并在极谱催化波的研究方面取得了突破性进展 ,并且大量用于实际工作中[1] 。由于经典的极谱分析法操作费时费力 ,一段时间内有被淘汰的趋势 ,但随着集成电路和芯片技术的发展 ,极谱仪也发生了革命性的突破 ,先是单板机示…     

生物样品中碳-14分析测量方法探讨

目的 对环境生物样品中碳-14测量分析方法进行优化研究,为环境生物样品中碳-14测量标准方法的制定提供技术支持。方法 通过对二氧化碳吸收法的优化研究,选用水分测定仪、元素分析仪测量生物样品的含水率、碳元素含量,简化人员操作、优化方法流程步骤,并开展方法实验室内、实验室间验证。结果 典型条件下,方法探测下限可达3 Bq/kg,实验室内相对标准偏差小于17%,实验室间相对标准偏差小于14%,相对误差小于19%;样品前处理更多由仪器设备直接完成,提高了样品含水率和碳元素含量测量的精密度和准确度,降低了实验人员操作差异对测试结果的影响。结论 优化后的方法探测下限、精密度、正确度等满足生物样品中碳-14测定有关要求。     

基于AD5933阻抗测量芯片的人体经穴阻抗动态监测系统研制

目的：设计人体经穴阻抗动态经络监测系统,明确人体经穴阻抗在低中频范围内响应规律。方法：系统采用STM32系列单片机STM32F103RBT6作为控制器,对阻抗测量芯片AD5933内部寄存器读写从而控制阻抗测量,外接ADG711模拟开关以实现不同量程范围,选用SGM4782双路模拟开关选通A、B两个通道,并在AD5933芯片的Vout脚和Vin脚间加入基于AD844的恒流源,采样数据通过SD卡读入上位机并分析。结果：系统能够实时反映经穴阻抗在1～128 kHz扫频激励下阻抗曲线及数值。结论：基于AD5933阻抗测量芯片的人体经穴阻抗动态经络监测系统可以准确反映经穴阻抗信息,可作为进一步明确针灸经穴阻抗特性研究工具。     

用两种效率刻度方法测量比对土壤介质放射性核素

目的 为了检验和提高γ谱仪测量准确性。方法 本实验室参加了由IAEA组织的土壤介质放射性核素测量比对活动。结果 分别采用由标准源刻度的和无源模拟刻度的效率曲线法,使用低本底高纯锗γ谱仪对土壤样品进行测量,通过相对偏差、Z检验、U检验、准确度和精确度等综合检验方法对测量结果进行了比对测试。结论 此次比对数据结果为"可以接受",从而验证了效率曲线刻度来源(包括无源模拟)的可靠性。     

便携式γ谱仪ISOCS无源效率刻度方法的研究

目的 通过对便携式HPGe γ谱仪无源效率刻度结果的准确性验证为核事故现场应急测量结果的可靠性提供依据。方法 采用ISOCS无源效率刻度系统方法对三种环境标准源样品,气溶胶滤膜、液体样和生物样进行验证实验。结果 便携式HPGe γ谱仪对人工核素的测量结果是可接受的,尤其对高能核素的测量准确度较高。结论 无源效率刻度法可用于核事故应急现场对简单体源模型的活度测量。     

基于无源效率刻度方法的实验室Y谱仪测量样品尺寸优化设计

目的实验室HPGe1谱仪测量样品的几何尺寸优化设计,针对一定质量的样品,给出探测效率最高时样品的尺寸。方法基于无源效率刻度方法,计算出不同几何尺寸下的实验室HPGey谱仪对圆柱形聚乙烯盒封装的1500g土壤样品的探测效率,作探测效率与样品盒直径的关系曲线,求出探测效率最大时的直径范围。另外采集野外未受人为干扰的表层土壤分装在不同尺寸的聚乙烯盒内进行测量验证。结果计算结果与实验测量值相吻合,表明计算的效率曲线可靠,对曲线进行多项式拟合后得出了最大效率处的几何尺寸。结论基于无源效率刻度方法可以较方便可靠地对实验室HPGeY谱仪测量样品的几何尺寸进行优化设计。     

基于HPGe谱仪的土壤介质放射性样品测量比对分析

目的 为了检验和提高γ谱仪分析性能和测量准确性,本实验室参加了由中国辐射防护研究院组织的土壤介质放射性样品测量比对活动。方法 采用效率曲线法,利用低本底高纯锗γ谱仪对一个模拟土壤样品进行测量比对,通过相对偏差、Z检验、U检验、准确度和精确度等多种检验方法对测量结果进行了分析讨论。结果 此次比对数据的结果可以接受。结论 验证了我实验室的检测方法可靠,质控措施可行,检测结果可信。     

NaI(Tl)γ能谱谱线分析技术的研究

目的 提高NaI(Tl)γ能谱的测量精度,拓展其应用范围。方法 针对NaI(Tl)γ能谱的谱型特征,利用权重最小二乘法进行解谱。结果 介绍了低本底NaI(Tl)γ能谱仪的常用解谱方法,着重介绍了权重最小二乘法(WLSQ)的原理和算法,并在Matlab平台下编程。结论 同一样品谱利用WLSQ求解的结果与HPGe谱仪测量的结果的偏差小于10%。     

Non-invasive stimulation of the P6 (Neiguan) antiemetic acupuncture point in cancer chemotherapy.

The beneficial effects of transcutaneous electrical stimulation of the P6 antiemetic point (Neiguan) as an adjuvant to standard antiemetics was studied in over 100 patients in whom chemotherapy-induced sickness was not adequately controlled by antiemetics alone. Although the results were not quite as good as with invasive acupuncture, more than 75% patients achieved considerable benefit from what was a non-toxic procedure. The use of large diffuse low impedence electrodes simplifies the technique. The 2 hourly application of Sea Bands prolongs the antiemetic action. Best results were obtained from the 2 hourly self-administration of 5 min of transcutaneous electrical stimulation of P6 using a simple battery-operated TENS machine (15 Hz) to activate a large, easy-to-place surface electrode and increasing current until Qi is elicited.     

阻塞性睡眠呼吸暂停低通气综合征患者呼吸阻抗的测定

目的　探讨阻塞性睡眠呼吸暂停低通气综合征 (OSAHS)患者呼吸阻抗的特征和临床意义。方法　测定并分析 5 2例OSAHS患者、13例COPD患者、17例健康人多导睡眠图 (PSG)、脉冲振荡法 (IOS)指标。结果　⑴OSAHS组总呼吸阻抗、中心气道阻抗、R2 0明显高于正常对照组 (P <0 0 5 ) ;响应频率、外周气道阻抗、R5、R5 -2 0、X5、X3 5与正常对照组无显著差异 (P >0 0 5 )。⑵OSAHS组响应频率、总呼吸阻抗、外周气道阻抗、R5、R5 -2 0明显低于COPD组 (P <0 0 1)。⑶OSAHS患者SaO2 与总呼吸阻抗、中心气道阻抗、R5、R2 0呈负相关 (P <0 0 1) ,AHI与总呼吸阻抗、中心气道阻抗、R5、R2 0呈正相关 (P <0 0 1)。结论　OSAHS患者IOS表现为上气道阻力升高 ,并与病情程度相关。     

Evaluation of thermal comfort in a student population: predictive value of an integrated index (Fanger's predicted mean value

Practical applications and predictive values of a thermal comfort index (Fanger's PRV) were verified on a sample school population (1236 subjects) by studying the relationships between thermal sensations (subjective analysis), determined by means of an individual questionnaire, and the values of thermal comfort index (objective analysis) obtained by calculating the PMV index individually in the subjects under study. In homogeneous conditions of metabolic expenditure rate and thermal impedence from clothing, significant differences were found between the two kinds of analyses. At 22 degrees C mean radiant and operative temperature, the PMV values averaged 0 and the percentage of subjects who experienced thermal comfort did not exceed 60%. The high level of subjects who were dissatisfied with their environmental thermal conditions confirms the doubts regarding the use of the PMV index as a predictive indicator of thermal comfort, especially considering that the negative answers were not homogeneous nor attributable to the small thermal fluctuations (less than 0.5 degree C) measured in the classrooms.     

手机无线显微成像技术

提出并实现了一种将手机与光学显微设备相结合的手机无线显微系统。该系统由手机、网络摄像仪．微型显微镜或高倍率显微镜等构成。在对常规物体及小鼠肿瘤组织切片等进行的系列概念性显微观察实验表明．这种显微方法可通过手机以无线方式接收显微图像,观察不受地点限制,设备体积小巧．成本低,在无干扰性研究细胞,组织培养以及危险生物样品的远程观测等方面可望有较广的适用面。     

一种生理弱电信号的模拟处理电路的设计

本文介绍了我们在心室晚电位研究过程中所研制成功的生理弱电信号模拟处理电路。该电路综合考虑了噪声、输入阻抗、共模抑制比和基线漂移等各项指标，采用了新近推出的高性能芯片ＡＤ６２０，并通过精细的工艺设计予以实现。测试表明该电路是稳定的、有效的。     

Equipment grounding affects contact current exposure: a case study of sewing machines

Exposure to contact current may occur when the body is in contact with two conductive surfaces with different electrical potentials. To date, no published data that describe such exposures or electrical conditions that may predispose to such exposures exist. Our investigation into contact current exposure included (i) a small sample of workers in a garment production facility with modern well-grounded equipment performing normal work tasks and (ii) a single individual simulating garment production tasks in a sewing machine repair facility with substandard equipment grounding. In both cases, we deployed a newly developed personal monitor that records contact current events at the power frequency of 60 Hz. The personal monitoring data suggested that more frequent exposure occurs in association with, and probably because of, poorer grounding practices. This preliminary conclusion was validated with controlled laboratory measurements of potentials to reference ground on specific locations of four sewing machines with different grounding characteristics. Propensity to exposure was greater in the two machines with inferior grounding characteristics, and increased in the other two when deprived of their grounding connections. Contact currents at or below threshold-of-perception levels can produce electric fields within tissues that may plausibly produce biological effects. On this basis, such exposures have been under-investigated relative to the far greater attention accorded to occupational electric and magnetic fields.     

结肠的快速虚拟外翻方法

针对结肠空腔结构的电场线虚拟外翻运行速度慢的问题.我们提出了一种对结肠数据进行快速虚拟外翻的方法.此法采用了垂直截面和电场线曲截面结合的横截面代替了电场线虚拟外翻方法的完全由电场线形成的横截面.对一组病人的结肠CT数据进行了上述两种方法的外翻比较.结果表明在图像质量基本相同的情况下,快速外翻方法的运行时间约为电场线虚拟外翻运行时间的1/6.     

生命银行系统建设与应用实践

“生命银行”是近年来发展起来的一种大型生物样品库系统。新近设计并应用一种新型生物样品库,该系统库结构设置、工作流程合理,相应的计算机管理系统具有高效、稳定、安全,操作容易、管理方便的优点。系统对捐献者的所有资料实行全程条码化管理,保证了研究数据的准确性和可靠性,提高了工作效率、管理质量和管理层次。整套管理系统运作流畅,已经收集和储存了近20,000人份的生物活性样品,每天可以完成50位捐献者的研究资料收集和生物样品处理及保存工作。该系统库已达到国际同类先进水平,具有良好的应用和推广价值。     

Comparative ecotoxicity of three polluted industrial soils for the Collembola Folsomia candida

We tried to quantify the ecotoxicity of three industrial soil samples contaminated by different metals, using the Collembolan Folsomia candida as a biological model and mortality, growth and reproduction as parameters. The observed ecotoxicities are rather normal for the first such soil sample (aluminum factory) but are high for the second sample (ore treatment) and relatively low for the third one (zinc factory) considering its high metal concentrations. For these last two soil samples, an unusual ecotoxicity plotting is observed: two high ecotoxicity recordings fit with a low and high percentage of polluted soil to non-polluted soil and noticeably lower ecotoxicity recordings are observed between them. Chemical analyses of metals in pore waters show that arsenic probably explains part of such an unusual ecotoxicity curve. Otherwise, mortality and growth of the animals are less sensitive parameters than reproduction. Our experiments show that the results of the ecotoxicological assays of polluted soils are complex and difficult to interpret.     

Quality management for the collection of biological samples in multicentre studies

Large scale international multicentre studies require sophisticated quality management for the collection, processing and logistics of biological samples to ensure a maximum degree of standardisation across different environmental conditions and settings. This paper describes a quality management system for the collection of biological samples (QMS-BS) which was applied during IDEFICS, a large European multicentre study. The application was evaluated by several criteria like response rates for the different types of biological samples, measures of sample quality, compliance with the QMS-BS and efficiency of the document and sample control and of the quality assurance system. Response rates varied from 56.6% for venous blood collection to 90.1% for saliva collection. All sample types were associated with problems of sample quality (e.g. haemolysis of blood samples, lack of cooling for urine samples or desiccation of saliva samples). Overall compliance with the QMS-BS was good, with some exceptions mainly related to sample control. In conclusion the QMS-BS is a valuable tool for the management of biological sample collection in epidemiological multicentre studies.