便携式动脉硬化评估仪

该文研制了一种针对家庭监护的便携式动脉硬化评估仪器。该仪器由传感器模块、采集板和嵌入式模块构成。传感器模块包含一路心电模块和三路脉搏波提取模块,分别同步提取人体的心电信号和颈动脉、桡动脉及足背动脉的脉搏波信号。采集板将传感器模块的模拟输出信号转化为数字信号并将该数字信号传输至嵌入式模块。嵌入式模块完成信号的显示、存储及脉搏波传输速度的参数计算和输出。实现的动脉硬化评估仪器结构简单、使用方便、易于扩展,具有小体积、低成本、低功耗的特点。通过实验验证,这种便携式的动脉硬化评估仪器准确性高,重复性好,能较好地评估人体的动脉硬化程度。     

适用于脉搏波传导时间测血压准确性研究的多信号采集系统

目的：设计一种可用于脉搏波传导时间法测量血压准确性研究的多信号采集系统。方法：分析可能影响准确性的几方面因素,设计可采集多参数的系统及可用于个性化校正的模块,可与DSP运算模块无缝连接的数据接口等结果：分别采用2种测量方法测量脉搏波传导时间,20人次的测量实验表明,多参数信号质量较好,经过软件简单滤波后即可准确定位各特征点,便于计算脉搏波传导时间,进行算法研究。采集系统可与DSP运算模块无缝连接构建实验平台。结论：适用于脉搏波传导时间研究的多信号采集系统可用于脉搏波传导时间法测量血压准确性的研究     

动态脉搏信号的采集与处理

为实现脉搏信号的实时采集与处理,根据动态脉搏信号的噪声特点,设计了整系数陷波、低通滤波器,并提出了包络滤波法。应用MATLAB仿真软件进行验证,并通过简化编程,在DSP上实现对脉搏信号的实时滤波。通过DSP系统对脉搏信号进行时域和频域分析,实时计算其波高、脉率并对其进行FFT变换。结果表明,设计的系统能有效抑制脉搏信号中的噪声,可实现动态脉搏信号的实时检测与处理。     

血氧饱和度实时监测中脉搏波信号的预处理

目的:对光电脉搏式血氧饱和度监测系统采集的脉搏波信号进行预处理,提高参数计算的实时性与准确性。方法:对原始脉搏波信号噪声特点进行分析,提出相关的预处理方法并设计相应的滤波器,利用Matlab数据分析软件对脉搏波信号及相关参数进行仿真处理。结果:原始脉搏波信号经处理后,在提高运算精度的同时消除了噪声干扰。结论:实现了血氧饱和度的实时快速测量和动态监测显示,为血氧饱和度参数的计算奠定了基础。     

基于C8051F020单片机的脉搏波信号发生器的设计

目的:设计一种脉搏波信号发生器,能够发出代替人体实际脉搏波的信号,将其发送至各类脉搏波信号检测仪器中,以求调试和检查这类仪器的性能指标。方法:以C8051F020单片机为核心,通过USB接口连接上位机,获得所需的反映人体不同生理状态的脉搏波波形信号并存储,根据用户的不同选择,将脉搏波波形信号发送到指定的仪器上。结果:该脉搏波信号发生器可以方便的接收上位机发来的脉搏波波形信号,并将脉搏波波形信号储存在自身的Flash芯片中,脉搏波信号发生器可以发送各类脉搏波信号。结论:该脉搏波信号发生器结构简单、体积小,可以方便的发出各种脉搏波波形信号,并且每一种脉搏波信号都反映了人体的不同生理状态,属于专用信号发生器。     

基于单片机的脉搏信号采集电路设计

目的：依据中医脉诊理论,运用一套基于PVDF材料制作的脉搏传感器,并结合前置放大电路单元,设计基于单片机的脉搏信号采集电路,用于对脉搏信息的准确检测。方法：以电子技术原理为基础设计出用于脉搏信号调理的多级放大和滤波电路,并设计基于AT89C51单片机和A/D转换芯片AD0809的数据采集电路。结果：利用信号采集和数据放大电路对脉搏波进行有效的采集处理与放大,可以使传统中医理论与现代科学理论有机结合,极大降低误诊率,有效的实现了脉诊客观化。结论：基于AT89C51单片机和A/D转换芯片AD0809的数据采集电路可以基本完成对脉搏信号的采集处理,信号放大比较明显,对脉诊客观化有一定的促进作用。     

基于积分放大器IVC102的脉搏数据采集系统

目的:为了实现对积分放大器IVC102的进一步研究,搭建硬件电路,实现对光电容积脉搏波的无创采集。方法:在较为嘈杂的环境中,利用搭建的硬件电路,由血样探头传感器将人体指端光电容积脉搏波转换成电流信号输出,并由积分放大器进行电流到电压的转换,同时实现滤波放大,经AD转换后被MSP430单片机采集,送到上位机存储、显示,并进行数据处理。同时利用临床现有的脉搏采集方法实现人体脉搏波的同步采集,将2种脉搏波进行对比和相关参数计算。结果:观察发现采集得到的光电容积脉搏波具有一般脉搏信号的普遍特征,波形相似度较高,说明系统实现了正常采集。结论:该系统具有较强的抗干扰、抗噪声能力,能在复杂的环境下准确提取人体指端光电容积脉搏波。该系统也可以应用在其他采集过程中,实现电流-电压转换,并在一定程度上完成滤波和放大作用。     

基于AVR单片机的数字血氧模块的开发

利用光频传感器TSL235与8位AVR单片机MEGA8,开发小型的微功耗血氧模块,实现血氧饱和度和脉搏监护。该模块低功耗、弱灌注,具有良好的基线控制功能,可达到运动测量的目的。     

基于循环平稳算法的脉搏信号质量评估与滤波

针对实际采集脉搏信号中各种噪声对信号质量的影响,采用循环平稳算法对脉搏信号进行质量评估与滤波。首先,根据循环谱提出脉搏信号的质量评价指标——质量系数,评估脉搏信号受噪声影响程度;然后,设计循环相关匹配滤波器对脉搏信号滤波。采用建模产生的脉搏信号与MIT-BIH噪声数据库提供的噪声信号叠加产生实验数据,对提出的质量评估与滤波方法进行验证,并将所提出方法应用于实际采集的脉搏信号。结果表明,质量系数可以准确地反映脉搏信号的质量;循环相关匹配滤波器可以有效地消除脉搏信号中的噪声。     

腕部气囊式脉搏波自动采集装置的研制

目的:研制一种可以在测量血压的同时采集脉搏波信号并得到心血管评价参数的医疗电子仪器,对实现心血管功能日常监测具有重要意义。方法:将气压式传感器采集腕部气囊内压力信号转换为电信号,通过信号处理电路将其分为接近直流的气囊压力信号和脉搏波信号,经过并行模拟数字(A/D)转换后,利用单片机控制气泵和气阀的充气、放气通断,以实时判断气囊压力值和脉搏波波幅,从而计算出平均动脉压,采集桡动脉压力信号。结果:基于示波法血压自动测量方式可根据脉搏波波幅与袖套压力的对应关系确定平均动脉压,并计算得到收缩压和舒张压,在平均动脉压对应的袖套压力状态下采集到人体桡动脉压力脉搏波波形。结论:该装置可提供一种在测得人体腕部血压的同时自动无创的采集脉搏波的方法。     

基于SPCE061A脉搏测量仪的设计与实现

目的：设计一种主要用于临床上检测脉搏的脉搏测量仪。方法：采用光电传感器检测脉搏信号,通过放大、滤波、整形电路将脉搏波信号转换为方波信号,SPCE061A单片机对转换后的方波信号进行检测并计算每分钟脉搏数,最后通过液晶显示脉搏测量值。结果：该测量仪能够在误差小于±1%的条件下对脉搏进行测量。结论：该测量仪能够实时、连续地对脉搏进行准确监测,可以满足临床对脉搏测量的需要,同时也可以为家庭提供帮助。     

Total airborne mold particle sampling: evaluation of sample collection, preparation and counting procedures, and collection devices

This study was conducted to evaluate (i) procedures used to collect, prepare, and count total airborne mold spore/particle concentrations, and (ii) the relative field performance of three commercially available total airborne mold spore/particle sampling devices. Differences between factory and laboratory airflow calibration values of axial fan-driven sampling instruments (used in the study) indicated a need for laboratory calibration using a mass flow meter to ensure that sample results were accurately calculated. An aniline blue-amended Calberla's solution adjusted to a pH of 4.2-4.4 provided good sample mounting/counting results using Dow Corning high vacuum grease, Dow Corning 280A adhesive, and Dow Corning 316 silicone release spray for samples collected using mini-Burkard and Allergenco samplers. Count variability among analysts was most pronounced in 5% counts of relatively low mold particle deposition density samples and trended downward with increased count percentage and particle deposition density. No significant differences were observed among means of 5, 10, and 20% counts and among analysts; a significant interaction effect was observed between analysts' counts and particle deposition densities. Significantly higher mini-Burkard and Air-O-Cell total mold spore/particle counts for 600x vs. 400x (1.9 and 2.3 x higher, respectively), 1000x vs. 600x (1.9 and 2.2 x higher, respectively) and 1000x vs. 400x (3.6 and 4.6 x higher, respectively) comparisons indicated that 1000x magnification counts best quantified total airborne mold spore/particles using light microscopy, and that lower magnification counts may result in unacceptable underreporting of airborne mold spore/particle concentrations. Modest but significantly higher (1.2x) total mold spore concentrations were observed with Allergenco vs. mini-Burkard samples collected in co-located, concurrently operated sampler studies; moderate but significantly higher mini-Burkard count values (1.4x) were observed in similar studies with Air-O-Cell samplers. These count differences were relatively small compared with the large differences observed among three count magnifications.     

Hintergrundkonzentrationen von Schimmelpilzen in Luft

The mold concentration of indoor air and outdoor air in three parts of Germany was investigated in both winter and summer. In total, air samples from 80 dwellings, reportedly free from mold infestations, were analysed with both the cultivation method and the total spore count method. With the cultivation method, 40 mold species and genera were differentiated, while with the total spore count method, 11 spore types were distinguished. The concentration of the genera Alternaria, Cladosporium, Fusarium and yeast increased in summertime. In contrast, the concentrations of Aspergillus and Penicillium measured in summer were nearly equal to those measured in winter. The majority of the various molds were only found in a small number of samples, too small for a reliable comparison of the winter and summer findings. The 95th percentile of the indoor mold concentrations is suggested as the upper limit of the background concentration. The results are discussed comparing the assessment proposals of various authors, and a new assessment proposal is described.     

Assessment of fungal contamination in moldy homes: comparison of different methods

In an effort to better understand the relationship between different fungal sampling methods in the indoor environment, four methods were used to quantify mold contamination in 13 homes with visible mold. Swab, fungal spore source strength tester (FSSST), and air samples (total of 52 samples) were analyzed using both the microscopic (total spore count) and culture-based (CFU count) enumeration techniques. Settled dust samples were analyzed for culturable fungi only, as the microscopic enumeration was restricted by the masking effect. The relationships between the data obtained with the different sampling methods were examined using correlation analysis. Significant relationships were observed between the data obtained from swab and FSSST samples both by the total counting (r = 0.822, p < 0.05) and by the CFU counting (r = 0.935, p < 0.01). No relationships were observed between air and FSSST samples or air and settled dust samples. Percentage culturability of spores for each sampling method was also calculated and found to vary greatly for all three methods (swab: 0.03% to 63%, FSSST: 0.1% to > 100%, air: 0.7% to 79%). These findings confirm that reliance on one sampling or enumeration method for characterization of an indoor mold source might not provide an accurate estimate of fungal contamination of a microenvironment. Furthermore, FSSST sampling appears to be an effective measurement of a mold source in the field, providing an upper bound estimate of potential mold spore release into the indoor air. Because of the small sample size of this study, however, further research is needed to better understand the observed relationships in this study.     

Assessment of safety of frozen foods

This study aimed to assess the microbiological quality of 90 frozen food samples (50 samples of raw frozen vegetables including molokeya, okra, green peas, peas + carrot, and artichoke, 20 of frozen poultry products and 20 of frozen meat products), and to assess the level of women practice during handling. A cross-sectional study was conducted. Results showed that the mean aerobic mesophilic plate count of frozen vegetables was 3.4 x 10(5) +/- 7.3 x 10(5) cfu/g. The mean mold and yeast count was 3.9 x 10(3) +/- 1.1 x 10(4) cfu/g. The mean coliform count was 3.9 x 10 +/- 6.6 x 10 m.o./g. In case of meat product, the mean aerobic count was 2.3 x 10(5) +/- 3.2 x 10(5), that of mold and yeast was 2.5 x 10(5) +/- 8.8 x 10(5) cfu/g and that of coliform was 3.2 x 10(2) +/- 3.8 x 10(2) m.o./g. Poultry products on the other hand had a mean aerobic count of 6.8 x 10(5) +/- 1.6 x 10(6), a mean mold and yeast count of 3.5 x 10(5) +/- 7.4 x 10(5) cfu/g and a mean coliform count of 6.4 x 10(2) +/- 5.2 x 10(2) m.o./g. Fecal coliforms were detected only in 60.0% of meat product samples and in 45.0% of poultry product samples. On the other hand Staph aureus was detected only in 10.0% of poultry product samples. Difference between the 5 types of vegetables was statistically significant (P = 0.00, and 0.02, respectively) for total plate and mold and yeasts counts. Among the 113 interviewed women, 80 used frozen food products. Twenty six of them (32.5%) had scores < 50%, those were classified as being bad as they were handling frozen food improperly which would contribute to outbreaks of food borne diseases. Less than 4% of the users used satisfactory practice during handling frozen foods. Illiteracy affected significantly the level of practice.     

一种监测人体体温及脉搏波的耳机装置

目的:设计一种安装在耳机上的实时检测人体体温及脉搏波信号的辅助装置,使人们在不影响生活工作的同时,轻松便捷地关注自己的健康状况。方法:置于耳机上的反射式光电传感器采集脉搏波信号,热电堆红外温度传感器采集体温信号。信号经过滤波、放大和A/D转换后,利用嵌入在耳机内的单片机分别对脉搏波及体温信号进行处理,以得到心率和体温数据。并将处理后的脉搏波波形、心率数据及体温数据显示在液晶显示屏上,还可通过SD卡接口进行数据传输及存储。结果:经过实际测试,传感器能够测得人体耳部体温、提取耳部脉搏波信号,具有测量人体脉搏波、心率及体温的功能。结论:该耳机装置是一种可为用户提供实时检测体温、脉搏波及心率的便携式装置。     

樟脑油精药效及其安全性评价

目的：评价樟脑油精喷剂的药效及其在使用中的安全性。方法：将樟脑油精涂于裸露皮肤上,进行驱蚊试验。取白色念球菌（ＡＴＣＣ１０２３１）悬液加入樟脑油精,观察对真菌的抑制作用,急性经口毒性试验采用一次性灌胃给药;急性皮肤刺和眼刺激试验直接涂药于家兔皮肤和滴药于眼结膜囊内。结果：驱蚊保护时间达６h以上;抑菌率达９９．９９％;小鼠急性经口ＬＤ５０为１３０２．２５mg／kg;对家兔皮肤刺激积分值为０,４８h后对眼刺激平均指数为０．５。结论：本品对蚊虫有一定驱避保护作用,对霉菌生长有较强的抑制作用,而且毒性低,使用安全。     

基于LabVIEW的脉搏信号基线漂移去除

目的:去除脉搏波信号中存在的基线漂移等干扰噪声,提取清晰的脉搏信号以便于诊断、治疗心血管疾病。方法:采用LabVIEW作为软件平台、NI数据采集卡为硬件平台,研制了一套测量系统。该系统将传感器采集到的脉搏信号通过采集卡传送到PC,采用样条插值拟合的方法,去除信号中的基线漂移。结果:通过分析信号的频谱表明,处理后脉搏波的信噪比得到了明显改善。结论:该系统对脉搏信号中的基线漂移去除效果良好。