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find Keyword "节律" 20 results
  • Effects of Amlodipine Tablets (Norwasc) on the DayNight Rhythm of Blood Pressure and Ambulatory Arterial Stiffness Index in the Elderly with Essential Hypertension

    目的:观察氨氯地平片治疗非杓型老年高血压患者对血压昼夜节律异常及对动态动脉硬化指数(AASI)的影响。方法:80例患者每日晨8时顿服氨氯地平5~10mg/d,服药前及治疗8周后行24h动态血压监测。结果:80例完成治疗的患者中,60例血压昼夜节律异常逆转,同时改善AASI。而20例血压昼夜节律无逆转,AASI与治疗前比较无差异。结论:经氨氯地平片治疗后,75%的非杓型高血压患者,可改善血压昼夜节律异常及AASI。

    Release date:2016-09-08 10:01 Export PDF Favorites Scan
  • The Role of Actigraphy in Monitoring Sleep and Sleep Disorders

    The use of actigraphy, which can be used to estimate sleep-wake patterns from activity levels, has become common in sleep research. Actigraphy is a simple, cost-effective and non-invasive method for healthcare providers and researchers to assess patients sleep quality and screen for potential sleep disorders in recent years. But, there is no wide recognition and application of actigraphy in China up till now. This review summarized the application of actigraphy in evaluation of sleep and diagnosis of sleep disorders.

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  • Motor Cortex Functional Mapping Using Electrocorticography

    The main shortcomings of using electrocortical stimulation (ECS) in identifying the motor functional area around the focus in neurosurgery are certainly time-consuming, possibly cerebral cortex injuring and perhaps triggering epilepsy. To solve these problems, we in our research presented an intraoperative motor cortex functional mapping based on electrocorticography (ECoG). At first, using power spectrum estimation, we analyzed the characteristic of ECoG which was related to move task, and selected Mu rhythm as the move-related feature. Then we extracted the feature from original ECoG by multi-resolution wavelet analysis. By calculating the sum value of feature in every channel and observing the distribution of these sum values, we obtained the correlation between the cortex area under the electrode and motor cortex functional area. The results showed that the distribution of the relationship between the cortex under the electrode and motor cortex functional area was almost consistent with those identified by ECS which was called as ‘the gold-standard’. It indicated that this method was basically feasible, and it just needed five minutes totally. In conclusion, ECoG-based and passive identification of motor cortical function may serve as a useful adjunct to ECS in the intraoperative mapping.

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  • Study of the Effect of Cholecystokinin-Induced Acute Pancreatitis on the Free-Running Rhythm of Mouse

    The present paper reports the effect of pancreatitis induced by cholecystokinin (CCK) on free-running rhythm of locomotor activity of the ICR mice, and analyzes the interaction of inflammatory diseases and acute pancreatitis with circadian rhythm system. In the study, the mice were modeled under different phases of acute pancreatitis in DD status (Double Dark,constant dark condition). By comparing of the inflammatory status and the indicators of rhythm before and after modeling of the running wheel activity group and the rest group, it was observed that the rest group showed more possibility of inflammation than the activity group did in ICR mice model of acute pancreatitis. In the rest phase model, the extension of the period is particularly longer. The results presented indicated that CCK-induced acute pancreatitis impacted free activity rhythm of ICR mice. Also in a free running model under different phase, the inflammation severity was proved significantly different. This study provides possible clues for the research of the pathogenesis of acute pancreatitis severe tendency.

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  • A New Algorithmic Method to Detect Ventricular Fibrillation Using Electrocardiogram Signals During Cardiopulmonary Resuscitation by Artificial Pressing

    On account of the mechanical disturbance of external chest pressing to electrocardiogram (ECG) signal, the ECG rhythm cannot be identified reliably during the cardio-pulmonary resuscitation period. Whereas the possibility of successful resuscitation will be lowered due to interrupted external chest pressing, a new filtering algorithm, enhanced leastmean-square (eLMS) algorithm, was proposed and developed in our laboratory. The algorithm can filter the disturbance of external chest pressing without the support of hardware reference signal and correctly identify ventricular fibrillation (VF) rhythm and normal sinus rhythm in case of uninterrupted external chest pressing. Without other reference signals, this algorithm realizes filtering only through the interrupted electrocardiograma (cECG) signal. It was verified with ECG signal and disturbance signal under different signal to noise ratios and contrasted with other mature algorithms. The verification results showed that the identification effect of eLMS was superior to those of others under different signal to noise ratios. Furthermore, ECG rhythm can be correctly identified only through cECG signal. This algorithm not only reduces the research and development(R & D)costs of automated external defibrillator but also raises the identification accuracy of ECG rhythm and the possibility of successful resuscitation.

    Release date:2016-10-02 04:55 Export PDF Favorites Scan
  • High frequency stimulations change the phase-locking relationship between neuronal firing and the rhythms of field potentials

    Deep brain stimulation (DBS) has been successfully used to treat a variety of brain diseases in clinic. Recent investigations have suggested that high frequency stimulation (HFS) of electrical pulses used by DBS might change pathological rhythms in action potential firing of neurons, which may be one of the important mechanisms of DBS therapy. However, experimental data are required to confirm the hypothesis. In the present study, 1 min of 100 Hz HFS was applied to the Schaffer collaterals of hippocampal CA1 region in anaesthetized rats. The changes of the rhythmic firing of action potentials from pyramidal cells and interneurons were investigated in the downstream CA1 region. The results showed that obvious θ rhythms were present in the field potential of CA1 region of the anesthetized rats. The θ rhythms were especially pronounced in the stratum radiatum. In addition, there was a phase-locking relationship between neuronal spikes and the θ rhythms. However, HFS trains significantly decreased the phase-locking values between the spikes of pyramidal cells and the θ rhythms in stratum radiatum from 0.36 ± 0.12 to 0.06 ± 0.04 (P < 0.001, paired t-test, N = 8). The phase-locking values of interneuron spikes were also decreased significantly from 0.27 ± 0.08 to 0.09 ± 0.05 (P < 0.01, paired t-test, N = 8). Similar changes were obtained in the phase-locking values between neuronal spikes and the θ rhythms in the pyramidal layer. These results suggested that axonal HFS could eliminate the phase-locking relationship between action potentials of neurons and θ rhythms thereby changing the rhythmic firing of downstream neurons. HFS induced conduction block in the axons might be one of the underlying mechanisms. The finding is important for further understanding the mechanisms of DBS.

    Release date:2018-02-26 09:34 Export PDF Favorites Scan
  • Rhythm analysis of body surface potential mapping recordings from atrial fibrillation patients based on autocorrelation function

    The study of atrial fibrillation (AF) has been known as a hot topic of clinical concern. Body surface potential mapping (BSPM), a noninvasive electrical mapping technology, has been widely used in the study of AF. This study adopted 10 AF patients’ preoperative and postoperative BSPM data (each patient’s data contained 128 channels), and applied the autocorrelation function method to obtain the activation interval of the BSPM signals. The activation interval results were compared with that of manual counting method and the applicability of the autocorrelation function method was verified. Furthermore, we compared the autocorrelation function method with the commonly used fast Fourier transform (FFT) method. It was found that the autocorrelation function method was more accurate. Finally, to find a simple rule to predict the recurrence of atrial fibrillation, the autocorrelation function method was used to analyze the preoperative BSPM signals of 10 patients with persistent AF. Consequently, we found that if the patient’s proportion of channels with dominant frequency larger than 2.5 Hz in the anterior left region is greater than the other three regions (the anterior right region, the posterior left region, and the posterior right region), he or she might have a higher possibility of AF recurrence. This study verified the rationality of the autocorrelation function method for rhythm analysis and concluded a simple rule of AF recurrence prediction based on this method.

    Release date:2018-04-16 09:57 Export PDF Favorites Scan
  • 癫痫与昼夜节律

    癫痫是常见的神经系统疾病,由不同病因引起脑部神经元高度同步化异常放电所致,其发病率高,临床表现复杂,具有不可预测性。昼夜节律是调节机体行为、生理、生物化学的 24 h 模式。随着对癫痫研究的不断深入,癫痫与昼夜节律的关系越来越受到关注。癫痫发作具有昼夜节律,同一类型的癫痫在不同时间、不同状态发作的频率不同。癫痫发作可能会影响昼夜节律,包括睡眠与睡眠觉醒周期、核心体温、心血管参数、内分泌系统等。同时,昼夜节律变化可能导致癫痫发生,二者相互作用形成恶性循环,严重影响癫痫患者的工作、生活和学习。内源性昼夜节律系统可能是癫痫发作的独立危险因素。各种癫痫发作类型可能具有不同的昼夜节律分布,并且这些节律分布特点可能提供癫痫诊断线索和依据。明确癫痫发作的昼夜节律,根据其发作节律进行干预及治疗,既可以减少药物不良反应,还能有效控制癫痫发作。文章就癫痫与昼夜节律的相互关系进行综述。

    Release date:2019-01-19 08:54 Export PDF Favorites Scan
  • Review on the relationship between selective attention and neural oscillations

    Selective attention promotes the perception of brain to outside world and coordinates the allocation of limited brain resources. It is a cognitive process which relies on the neural activities of attention-related brain network. As one of the important forms of brain activities, neural oscillations are closely related to selective attention. In recent years, the relationship between selective attention and neural oscillations has become a hot issue. The new method that using external rhythmic stimuli to influence neural oscillations, i.e., neural entrainment, provides a promising approach to investigate the relationship between selective attention and neural oscillations. Moreover, it provides a new method to diagnose and even to treat the attention dysfunction. This paper reviewed the research status on the relationship between selective attention and neural oscillations, and focused on the application prospects of neural entrainment in revealing this relationship and diagnosing, even treating the attention dysfunction.

    Release date:2019-04-15 05:31 Export PDF Favorites Scan
  • 在癫痫猝死模型中昼夜节律改变和时钟基因及 Sirtuin 1 的振荡

    许多神经系统疾病都会影响昼夜节律。尽管已知癫痫常伴睡眠障碍,但与癫痫昼夜节律紊乱相关的数据却很少。文章检验了 Kcna1 缺失小鼠的昼夜休息活动以及睡眠-觉醒模式。该小鼠模型表现出反复自发癫痫发作,也是研究癫痫猝死的模型。此外,研究试图确定癫痫发作以及核心时钟基因和调节因子 Sirtuin 1(Sirt1)的异常变化是否与昼夜节律紊乱有关。研究使用被动红外活动记录仪评估休息活动模式,使用脑电图(EEG)进行癫痫发作和睡眠分析,并且使用逆转录聚合酶链反应和蛋白质印迹法评估时钟基因和 Sirt1 在 Kcna1 缺失和野生型小鼠中的表达情况。癫痫 Kcna1 缺失动物模型存在昼夜休息活动模式紊乱,趋于表现出延长的昼夜节律。EEG 分析证实了睡眠结构的破坏,清醒时间更多并且睡眠不足。尽管所有癫痫小鼠都表现出昼夜休息活动模式的紊乱,但该研究发现实际癫痫发作负担与睡眠紊乱程度之间没有相关性。发现前下丘脑中几个时钟基因(即 Clock,Bmal1,Per1 和 Per2)和昼间 Sirt1 mRNA 的衰减振荡。几个核心时钟基因的振荡衰减与 Kcna1 缺失小鼠中观察到的异常昼夜休息活动以及睡眠-觉醒模式改变相关,可能是其基础原因,并可能导致癫痫晚期并发症,例如癫痫猝死。Sirt1 可能是恢复生物钟基因节律和癫痫睡眠模式的潜在治疗靶点之一。

    Release date:2019-05-21 08:51 Export PDF Favorites Scan
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