心室晚电位的动态检测

本文在分析提取晚电位关键问题的基础上,提出一种新的逐拍提取心室晚电位的方法.其特点是把谱线增强、噪声抵消、通道均衡等自适应处理技术组合起来,结合梳形滤波来进行动态提取.仿真实验及少量临床数据处理结果证明了方法的可行性.只要把处理过程中滤波器的的频带适当变更,本法还可望适用于其他心电微电势的提取.     

增强心室晚电位信号的自适应滤波方法

介绍了一种基于自适应滤波的心室晚电位信号增强方法，这种自适应滤波器仅有一个信号电极而无需参考电极，实验结果表明这种自适应滤波方法可有效提高心室晚电位信号的信噪比。     

心室晚电位检测技术进展

本从心室晚电位的概念和产生机理,介绍了检测心室晚电位的时域,频域,时频域和人工神经网络等几种常见方法,进一步引出了自适应滤波的逐搏检测方法。     

心室晚电位检测处理技术的发展

心室晚电位(VLP)在心脏疾病诊断方面的价值已在临床上得到肯定.目前已有多种VLP检测系统,出现了各种VLP检测处理方法.文章首先归纳总结了VLP各种分析方法,详细给出了传统VLP时、频域分析方法的检测原理和存在的问题,介绍了最近出现的子波变换、神经网络方法,这些方法反映了VLP检测处理技术的新进展.     

心室晚电位检测技术进展

本文从心室晚电位的概念和产生机理 ,介绍了检测心室晚电位的时域、频域、时频域和人工神经网络等几种常见方法 ,进一步引出了自适应滤波的逐搏检测方法     

用叠加心电图无创性检测QRS波内心室晚电位的方法设计

用计算机进行心电信号叠加记录心室晚电位（VLP）是近年来发展的鉴别恶性室性心律失常病人的方法之一，但目前的计算机算法不能检测QRS波中的VLP，在一定程度上影响了VLP的检出率，如果对目前方法所得的叠加心电图进行光滑处理，将经光滑处理和未经光滑处理的叠加心电图相减，则可望显示出寄生于QRS波中及QRS波终末高频的微小波形，在制定VLP的阳性标准后即可判断其中是否存在VLP，使VLP的检出率得以提高，这种检测方法的正确性还有待于今后的研究验证。     

近似熵用于心室晚电位检测的研究

采用非线性动力学方法之一的近似熵分析,对心肌梗塞康复后有无晚电位的两类病人的高分辨率心电信号(HRECG)进行小波包变换后的近似熵进行分析。实验结果显示:晚电位阳性的病人往往有较高的近似熵值,而晚电位阴性的病人的近似熵较低,并且把总序列及小波包分解的分序列的近似熵应用于经过训练的BP人工神经网络后对心室晚电位有很好的识别率。     

心室晚电位研究的历史,现状与展望

心室晚电位是心肌延迟去极化产生的碎裂电位，位于心电图ＱＲＳ波群后期并延伸到ＳＴ段的微弱的电活动，在体表可用优良的放大电路和适当的分析处理而检测出来。心室晚电位技术是８０年代开始的一种心电图检查方法，本文较全面介绍了心室晚电位研究的历史，现状及展望，并对心室晚电位的提取与处理技术和病理与临床应用研究做了较具体的介绍和评述。     

心室晚电位处理技术研究进展

心室晚电位对预告心律失常具有较大的临床价值。本文较详尽地介绍了心室晚电位处理技术的研究现状,包括晚电位信号的模拟处理、在商用系统中广泛采用的时域法和频域法。指出心室晚电位处理的关键是如何提取动态晚电位信息,具体介绍了应用自适应处理和子波变换提取动态晚电位的进展。对心室晚电位的临床研究亦作了简要介绍。     

Influence of calcium/calmodulin on budding of Ebola VLPs: implications for the involvement of the Ras/Raf/MEK/ERK pathway

The VP40 matrix protein of Ebola virus is able to bud from mammalian cells as a virus-like particle (VLP). Interactions between L-domain motifs of VP40 and host proteins such as Tsg101 and Nedd4 serve to facilitate budding of VP40 VLPs. Since intracellular levels of calcium are known to influence localization and function of host proteins involved in virus budding, we sought to determine, whether alterations of calcium or calmodulin levels in cells would affect budding of VP40 VLPs. VP40 VLP release was assessed in cells treated with BAPTA/AM, a calcium ion chelator, or with ionomycin, a calcium ionophore. In addition, VLP budding was assessed in cells treated with W7, W13, or TFP; all calmodulin antagonists. Results from these experiments indicated that: (i) budding of VP40 VLPs was reduced in a dose-dependent manner in the presence of BAPTA/AM, and slightly enhanced in the presence of ionomycin, (ii) VP40 VLP budding was reduced in a dose-dependent manner in the presence of W7, whereas VP40 VLP budding was unaffected in the presence of cyclosporine-A, (iii) budding of VSV-WT and a VSV recombinant (M40 virus) possessing the L-domains of Ebola VP40 was inhibited in the presence of W7, W13, or TFP, (iv) inhibition of virus budding by W7, W13, and TFP appears to be L-domain independent, and (v) the mechanism of calcium/calmodulin-mediated inhibition of Ebola VLP budding may involve the Ras/Raf/MEK/ERK signaling pathway.     

生物磁感应成像中的高精度鉴相方法研究

用磁感应的方式测量组织的电导率是生物磁感应成像的基础,其测量精度将决定成像的质量.目前主要的测量方法是采用高频磁场作为激励,通过检测磁场穿过被测目标后的微小的相位变化来测量电导率.激励磁场的频率较高和生物组织电导率较小等因素增加了高精度鉴相的难度.已经应用于磁感应成像的鉴相方法存在分辨率不高线性度较差等问题.为此,设计并实现了一种高分辨率高线性度的鉴相方法,其相位分辨率为0.003°,线性相关系数大于0.99,提高了磁感应成像的精度.     

Technique for the evaluation of derivatives from noisy biomechanical displacement data using a model-based bandwidth-selection procedure

Smoothing and differentiation of noisy signals are common problems whenever it is difficult or impossible to obtain derivatives by direct measurement. In biomechanics body displacements are frequently assessed and these measurements are affected by noise. To avoid high-frequency noise magnification, data filtering before differentiation is needed. In the approach reported here an autoregressive model is fitted to the signal. This allows the evaluation of the filter bandwidth and the extrapolation of the data. The extrapolation also reduces edge effects. Low-pass filtering is performed in the frequency domain by a linear phase FIR filter and differentiation is performed in the frequency domain. The reported results illustrate the accuracy of the algorithm and its speed (mainly due to the use of the FFT algorithm). Automatic bandwidth selection also guarantees the homogeneity of the results.     

即刻法和Levey-Jennings法在ELISA检测HBsAg中的比较

目的 将2013年8月至2014年4月底每次ELISA法检测HBsAg试验的前20次质量控制数据分别用即刻法和Levey-Jennings法分析,探究这两种方法的优缺点及适用情况.方法对半年的质控数据先用即刻法统计分析,计算得到每组数据的(-x),CV,s,SI上限及SI下限,并将得到的SI上限,SI下限与SI界值表比较,若SI上限,SI下限均小于n2s,则表明试验在控,若有一值处于n2s和n3s之间,则为告警,若有一值大于n3s,则处于失控,对于失控和告警的数据都需舍去离散程度最大值,并查找原因,重新进行测定.同时对同批号质控物和同试剂的前20次质控数据进行计算得到,s,并以(-x),(-x)±3s建立质控框架图,将随后数据绘入Levey-Jennings质控图中,大于x+3s或小于x-3s的质控值视为失控状态,需查找原因,重新测量.结果 发现有两组数据在即刻法和Levey-Jennings法中呈现出不同的结果.即刻法中告警的数据在Levey-Jennings法中可以处于在控状态,而Levey-Jennings法失控的数据在即刻法中可能在控.结论 即刻法和Levey-Jennings法适用不同条件下的检测,对于检测频率较低的样本,即刻法显得更为合适.对于HBsAg来看,Levey-Jennings法更合适适用.     

离心法测定细胞与材料之间黏附强度的研究

建立一种简单的离心法用以评价细胞与材料之间的黏附强度。改造离心涂片机以适合研究需要；建立离心法测定三种贴壁细胞（HeLa、SH～SY5Y、ECV304）在两种材料（聚苯乙烯板、丝素蛋白膜）上的黏附强度，以研究在不同的培养时间下三种贴壁细胞在两种材料上的黏附情况。结果表明在相同的培养时间下，三种贴壁细胞与丝素蛋白膜的黏附强度强于与聚苯乙烯的黏附强度，其黏附强度的大小可以相对量化。结论该离心法检测细胞对生物材料黏附强度的方法简单易行，重复性高；丝素膜材料是一较为理想的生物材料。     

Potentiation of the resetting effects of light on circadian rhythms of hamsters using serotonin and neuropeptide Y receptor antagonists

Circadian rhythms are entrained by light/dark cycles. In hamsters, the effects of light on circadian rhythms can be modulated by serotonergic input to the suprachiasmatic nucleus from the raphe nuclei and by neuropeptide Y containing afferents to the suprachiasmatic nucleus from the intergeniculate leaflet in the thalamus. In this study we measured effects of compounds acting on serotonergic 1A and neuropeptide Y Y5 receptors to determine if combined serotonergic-neuropeptide Y inhibition could synergistically potentiate effects of light on rhythms. We used mixed serotonergic agonist/antagonists BMY 7378 or NAN-190 as well as a neuropeptide Y Y5 antagonist CP-760,542. Both BMY 7378 and NAN-190 are thought to block serotonin release via acting as agonists at the 5-hydroxytryptamine 1A (5-HT1A) autoreceptors on cells in the raphe, and also block response of target cells by acting as antagonists at post-synaptic 5-HT1A receptors, for example, in the suprachiasmatic nuclei or the intergeniculate leaflet. Replicating prior work, we found that pretreatment with either drug alone increased the phase shift to light at circadian time 19. The combined effect of BMY 7378 and CP-760,542 given prior to light at circadian time 19 was to further potentiate the subsequent phase shift in wheel-running rhythms (the phase shift was 317% of controls; light alone: 1.35 h phase shift vs. BMY 7378, CP-760,542, and light: 4.27 h phase shift). Combined treatment with NAN-190 and CP-760,542 produced a light-induced phase shift 576% of controls (phase shift to light alone: 1.23 h vs. NAN-190, CP-760,542, and light: 7.1 h phase shift). These results suggest that the resetting effects of light on circadian rhythms can be greatly potentiated in hamsters by using pharmacological treatments that block both serotonergic and neuropeptide Y afferents to the suprachiasmatic nuclei.     

大鼠三叉神经诱发电位检测方法的研究

目的 获得较佳的大鼠三叉神经诱发电位检测方法。方法 使用多导诱发电位仪在不同刺激及不同导联记录方法下检测大鼠三又神经诱发电位。结果 0．04ms波宽的电脉冲刺激和Cz-Cv7导联方法记录时，大鼠三叉神经诱发电位各导联波形重合较好，各波检出率均较高，潜伏期的标准差较小。结论 采用0.04ms渡宽电脉冲刺激和Cz-Cv7导联方法记录的大鼠三叉神经诱发电位较佳。     

用视动眼震电图定量评价视动机能和视动运动病易感性的初步探讨

本实验研究了视动知觉品质和视动运动病定量评价的可能性。结果表明,视动眼震的慢相速度和增益越大,视动知觉品质越高,视动运动病的敏感性也越低。根据阿拉伯数字和英文字母的距离10°,速度90～110°/s时的视动眼震电图可以区分视动知觉品质和视动运动病易感性的高低。     

Interaction between changes in local and temporospatial spectral EEG characteristics during exposure of humans to hypoxia

The temporospatial and local characteristics of the EEG were studied in healthy subjects during the respiration of a hypoxic oxygen-nitrogen gas mixture containing 8% oxygen. Analysis of the spectral power density, coherence, phase shift, similarity of dominant frequencies in the EEG in different leads was performed separately for epochs containing and not containing visually apparent patterns of EEG spatial synchronization. In addition, assessment of spectral measures took account of the fact of the dominance of the frequency being analyzed in the EEG spectrum of the corresponding lead. The results of these studies showed that overall, hypoxia was accompanied by a decrease in EEG coherence in the alpha range and, for connections in the left mid-temporal lead, the delta range. The beta range showed an increase in the values of this measure, while the theta range showed different changes in coherence: increases in epochs containing spatial synchronization patterns and decreases from control levels in other epochs. Hypoxia was also associated with increases in the EEG phase shift in the frontal and temporal leads (in relation to the EEG recordings in the other leads) in the delta and theta ranges. In the beta range, conversely, there was a decrease in the mean phase shift. Consideration of the fact of dominance of one or another frequency in the spectra of local EEG traces is needed for correct interpretation of analyses of temporospatial measures. A mathematical model of the interaction between processes at different frequencies is presented to explain some of the observations in the current work. __________ Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 91, No. 11, pp. 1260–1280, November, 2005.