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1.
子宫收缩对胎儿心率变异性非线性的影响   总被引:1,自引:0,他引:1  
目的对不同子宫收缩状态下,分析胎儿心率变异性的非线性混沌强度。方法采用非线性滴定方法,计算胎儿心率变异性的噪声极限,即非线性混沌强度;另用近似熵方法计算宫缩状态下胎儿心率变异性的复杂性。结果统计结果表明宫缩频率越高,计算所得到的噪声极限越大。说明随着外加刺激的增强,胎儿心率变异性的非线性混沌强度是增大的。但是近似熵方法不能反映相似的结果,宫缩反而使胎儿心率变异性的复杂性降低。  相似文献   

2.
健康人心率变异性中的不稳定周期轨道   总被引:2,自引:1,他引:2  
为刻划心脏节律存在的确定性动力学特征,运用不稳定周期轨道分析方法对健康青年人的RR间期时间序列数据进行分析。研究结果揭示健康人心脏节律中存在显著的不稳定周期轨道及不稳定周期轨道分级(周期1、周期2,周期3,周期4)现象,表明健康青年人心脏节律的动力学特性中包含着显著的确定性行为。通过跟踪不周期轨道随时间的演变,迹表明心脏节律的变化中存在着因有的非平稳性。  相似文献   

3.
不同年龄健康被试者心率变异性的谱分析研究   总被引:1,自引:0,他引:1  
对不同年龄健康男性被试者卧、立位条件下,心率变异性(heart rate variability,HRV)谱高、低频成分随年龄变化的规律进行研究。结果表明:虽然各年龄组间卧、立位时的静息平均心率并无显著差别,但HRV却随年龄的增长而明显降低,青年组HRV谱高、低频谱峰功率的显著高于中年组、中老年组及老年组(P〈0.05或P〈0.01);HRV谱低频谱功率、高频谱功率及总功率均随年龄增长呈指数衰减规  相似文献   

4.
崔成  赵孟辉 《蛇志》1998,10(3):13-14
目的 探讨蝮蛇抗栓酶伍用刺五加对冠心病心率异性的影响。方法 观察蝮蛇抗栓酶伍用刺五加对冠心病为异性的影响,并与对照组对比。结果 治疗组SDNN、HF、LF/HF改变较对照组有显著差异性(P〈0.01)。结论 该方法能显著提高冠心病患者的心率变异性,对冠心病源性猝死的预防有着重要意义。  相似文献   

5.
心率变异性 (heartratevariability ,HRV)正在被临床广泛用于作为疾病的诊断、治疗和愈后的指标。目前认为 ,在HRV频谱分析图中 ,高频波段 (highfrequency ,HF)与呼吸活动有关 ,由迷走神经单独介导。低频波段 (lowfrequency ,LF)受交感神经和副交感神经活动的双重调节。而极低频波段 (verylowfrequencyVLF)除受自主神经的调节外 ,还受温度、外周血管运动活动以及神经激素的影响。近来有报道在慢性心衰患者中 ,VLF与外周化学感受器的敏感性增加有关。本实验通…  相似文献   

6.
我们利用动物模型急性实验与慢性实验的方法,进行心率变异性参数的研究。实验结果表明:对于心脏上的损伤,心率变异性的时域指标有着显著的改变,能灵敏反映外来性调控和内在性调控双重作用。并且,在慢性实验的康复期中,心率变异性指标能够灵敏地反映心脏的内外调控过程,显示其有良好的临床使用价值。  相似文献   

7.
心率与血压的变异性:分析方法,生理意义及其应用   总被引:19,自引:0,他引:19  
本文回顾了关心回顾变异性及血压变异性的最新进展。在分析方法方面介绍了单一生理变量多变量系统的线性分析技术及其主要结果。对HRV/BPV谱的生理意义及其应用问题,也进行了回顾了评述。  相似文献   

8.
胡勇军  王长录  邹琼超  沈向前  王海昌 《生物磁学》2013,(30):5878-5880,5891
目的:研究冠心病合并脑梗死患者的心率变异性情况,和心律失常的发生率,分析它们的变化规律,为患者疾病的治疗及预后提供更好的治疗指导。方法:研究对象为2012年2月~2012年12月我院心内科及神经内科的患者,其中Ⅰ组:冠心病合并脑梗死患者40例、Ⅱ组:单纯冠心病患者40例、Ⅲ组:单纯脑梗死患者40例、以及Ⅳ组:健康成人50例,统计全部患24 h心率变异性及心律失常发生情况,并进行对比分析。结果:Ⅰ组患者的心率变异性和心律失常发生明显高于其它组患者,差异均具有统计学意义(P〈0.05)。且心率变异性时域参数下降,心律失常发生率升高。结论:冠心病合并脑梗死患者的心率变异性和心律失常发生率增高,为避免冠心病合并脑梗死的患者突然心律失常及猝死,应积极改变治疗措施。  相似文献   

9.
大鼠心率变异性频谱中高频成分的中枢机理分析   总被引:7,自引:0,他引:7  
Shen LL  Cao YX  Wu GQ  Li P 《生理学报》1998,50(4):392-400
本文探讨心率变异性(HRV)频谱中高频成分的中枢机理。对正常SD大量给予不同频率的人工通气并电刺激延髓疑核,观察HRV频谱的改变,记录与呼吸节律同步的延髓头端腹外侧区(rVLM)及其周围区神经元细胞外单位放电,对HRV和放电变异性进行相干函数分析。结果显示:(1)HRV的高频成分的中心频率随着人工通气频率的增加而增加,呈高度线性相关,(r=0.83,P〈0.0001);(2)对rVLM及其周围区与  相似文献   

10.
为阐明有氧锻炼对心脏自主神经调节功能的影响,以及这种变化与卧位/坐位下体负压(LBNP)作用下的心率调节及立位耐力之间是否有一定联系,用频域、动态谱及非线性指标较全面分析了大学生有氧锻炼6个月前、后心率变异性(HRV)的变化。结果表明:常规AR谱分析的批处理结果只能代表一段时间内HRV信号的平均统计特性,方差大,得不出有显著意义的结果。而时变AR谱则可反映LBNP作用下心迷走撤除及交感激活的动态过程。非线性的β估计得不出有显著意义的结果;但ApEn分析则可敏感地检测出有氧锻炼关联的心率动力学细微变化,且初步揭示ΔApEn与立位耐力变化(ΔDNP)间显著相关。以上对阐明有氧锻炼对心率动力学调节的影响以及改进HRV信号分析工作均有一定意义。  相似文献   

11.
Resting heart rate variability can be an index of sympathetic or parasympathetic dominance, according to the frequency of the variability studied. Sympathetic dominance of this system has been linked to increased risk of cardiovascular disease (CVD). Similarly, rapid and dramatic increases in heart rate reactivity to a stressor task have also been suggested as indicating increased risk of CVD via atherogenesis. Although both of these variables have been related to the development of cardiovascular disease, and both may be related to increased sympathetic activity or parasympathetic withdrawal, most research studies have tended to focus on either variable independently of the other. In order to investigate whether these two indices of stressor reactivity were related in relatively young and healthy subjects, resting heart rate variability data were collected from 80 volunteers for 20 minutes. In addition, heart rate reactivity data were collected during a 2-minute mental arithmetic stressor, which has been previously shown to induce significant increases in heart rate. After classifying subjects according to whether their heart rate variability data were above or below the mean for their gender, heart rate reactivity data were examined via MANOVA to detect significant differences between subject groups. Females showed significant effects, and males showed nonsignificant trends, but these two sets of data were in different directions, suggesting that gender may be a confounding factor in the relationship between heart rate reactivity and heart rate variability.  相似文献   

12.
目的探讨蝮蛇抗栓酶伍用刺五加对冠心病心率异性的影响。方法观察蝮蛇抗栓酶伍用刺五加对冠心病变异性的影响,并与对照组对比。结果治疗组SDNN、HF、LF/HF改变较对照组有显著差异性(P<0.01)。结论该方法能显著提高冠心病患者的心率变异性,对冠心病心源性猝死的预防有着重要意义。  相似文献   

13.
目的:了解心率变异性(heart rate variability,HRV)在不稳定型心绞痛(unstable angina pectoris,UAP)发病中的作用及其用于病情严重程度判断的价值;了解美托洛尔对UAP患者HRV的影响。方法:选择年龄、性别相匹配的UAP患者、SAP患者和健康人各60例做动态心电图检查,经Holter软件分析进行HRV时域指标的比较。UAP组动态心电图检查后加用美托洛尔25-50 mg/d(分两次口服),20天后重复动态心电图检查。结果:1UAP组与正常组比较各项指标均降低(P0.01)。2正常人HRV具有昼夜节律变化的特点,UAP组HRV昼夜节律变化性降低。3UAP病人服用美托洛尔后,心肌缺血、心律失常得到改善。结论:1.UAP患者心脏自主神经活性主要是副交感神经活性受损,交感神经活性相对占优势。2.无合并症的UAP病人HRV呈昼夜节律性降低。3.美托洛尔可改善UAP患者HRV。  相似文献   

14.
目的:研究互信息和自相关函数在睡眠各阶段心率变异性(heart rate variability,HRV)分析中的应用。方法:采用网络公开数据库SleepHeart Rateand Stroke VolumeDataBarhk,将RR序列分为30S一段,并以每30S数据为中心截取5minRR序列作为待分析对象。提取5minRR序列的互信息特征BDM、PDM和自相关函数特征BDC、PDC,然后用统计方法分析各特征在觉醒瓜EM/浅睡/深睡四种睡眠状态下的差异。结果:浅睡和深睡期间,BDM、PDM显著高于觉醒和REM睡眠(P〈0.001)。而BDC显著低于觉醒和REM睡眠(P〈0.001),PDC无显著差异(P〉0.05)。结论:①BDM、PDM和BDC从不同角度反映了不同睡眠阶段下RR序列的特征,它们或许与HRV不同的调节机制有关。@BDM、PDM和BDC可作为辅助HRV睡眠分期的新指标。  相似文献   

15.
As we previously reported, resonant frequency heart rate variability biofeedback increases baroreflex gain and peak expiratory flow in healthy individuals and has positive effects in treatment of asthma patients. Biofeedback readily produces large oscillations in heart rate, blood pressure, vascular tone, and pulse amplitude via paced breathing at the specific natural resonant frequency of the cardiovascular system for each individual. This paper describes how resonance properties of the cardiovascular system mediate the effects of heart rate variability biofeedback. There is evidence that resonant oscillations can train autonomic reflexes to provide therapeutic effect. The paper is based on studies described in previous papers. Here, we discuss the origin of the resonance phenomenon, describe our procedure for determining an individual's resonant frequency, and report data from 32 adult asthma patients and 24 healthy adult subjects, showing a negative relationship between resonant frequency and height, and a lower resonant frequency in men than women, but no relationship between resonant frequency and age, weight, or presence of asthma. Resonant frequency remains constant across 10 sessions of biofeedback training. It appears to be related to blood volume.  相似文献   

16.
Heavy or hazardous drinking is associated with an increased risk of cardiac morbidity and mortality and this has been attributed to abnormalities in cardiac autonomic regulation. Current study aimed to assess the role of simple indices derived from 12 lead ECG in subjects with chronic alcohol dependence. Data suggested that alcohol group had significantly lower 12 lead ECG derived RR variability compared to age and gender matched controls. Study further supports the implication of 12 lead derived RR variability indices in various clinical settings.  相似文献   

17.
The autonomic circadian rhythm plays an important role in asthma. In recent years it has become possible to evaluate autonomic nervous function (ANF) using analysis of heart rate variability (HRV). We analyzed the HRV in the 24h period following the state without an asthma attack in order to study the relationship between asthma and ANF. The HRV was analyzed in 94 asthmatic children (ages 5–15 years). These subjects were divided into groups according to the severity of their asthma. After recording a 24h ambulatory electrocardiograph (AECG), the HRV was analyzed by a computer. Evaluation of the HRV was carried out using time-domain and frequency-domain analyses. The ANF of asthma subjects was decreased in comparison to the normal group. The severity of asthma had a significant effect on the %RR50 (the proportion of cycles during which the difference is > 50 ms), the SD (standard deviation; mean of standard deviation of all normal RR intervals for all 5-minute periods), the low-frequency (LF) band (0.04 to 0.15 Hz), and the high-frequency (HF) band (0.15 to 0.4 Hz) (%RR50: F = 4.31, p = 0.01; SD: F=3.48, p = 0.03; LF: F=3.67, p = 0.02; HF: F=3.41, p = 0.03). These values were lowest in the severe asthma group. With regard to the therapy grouping, the index that exhibited a significant difference was the NNA (mean of normal-to-normal RR intervals over 24h) (F = 4.43, p = 0.01) In conclusion, even in the normal condition in which the patient is free of an asthma attack, the ANF of asthma sufferers differs from that of normal children. It is possible that the different ANF of asthma sufferers is related to the severity of the asthma. (Chronobiology International, 14(6), 597–606, 1997)  相似文献   

18.
摘要 目的:探讨对心力衰竭后室性心律失常患者应用参松养心胶囊联合胺碘酮进行治疗的效果。方法:选择150例心力衰竭后室性心律失常,根据随机数字表法,将150例患者分为A组、B组、C组,每组50例。所有患者均行常规抗心力衰竭治疗,A组患者给予参松养心胶囊治疗,B组患者给予胺碘酮片治疗;C组给予胺碘酮片联合参松养心胶囊治疗。对比三组的疗效,对比三组治疗前后的心功能指标、24 h动态心电图指标、心率变异性指数,对比三组治疗过程中的不良反应发生情况。结果:C组治疗有效率明显较A组、B组高(P<0.05),A组、B组间对比无统计学意义(P>0.05)。与治疗前相比,A、B、C三组的LVDs、LVDd降低,LVEF、CO、SV明显升高,且C组较A、B组比较有相同趋势(P<0.05);A组与B组间对比无统计学意义(P>0.05)。与治疗前相比,A、B、C三组的室性心动过速数量、室性早搏数量、QTd明显降低,QTc升高,且C组较A、B组比较有相同趋势(P<0.05);A组与B组间对比无统计学意义(P>0.05)。三组不良反应发生率比较无差异(P>0.05)。结论:与单独应用参松养心胶囊、胺碘酮相比,参松养心胶囊联合胺碘酮会提高疗效,且应用安全,可能与其可改善患者的心率变异性有关。  相似文献   

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