甲状腺功能亢进症患者植物神经功能的昼夜周期改变

目的 研究甲状腺功能亢进症(甲亢)患者植物神经功能的昼夜周期改变.方法 记录33例初发甲亢患者(甲亢组)和35例健康体检者(对照组)的24 h动态心电图,并通过心率变异性的时域和频域分析来评价心脏植物神经功能状态.结果 甲亢组所有NN间期的标准差(SDNN);以5 min为间隔将24 h连续记录分为288段,先计算每段的平均NN间期,然后计算288个NN间期平均值的标准差(SDANN);以5 min为间隔将24 h连续记录分为288段,先计算每段的NN间期标准差,然后计算288个NN间期标准差的平均值(ASDNN);所有相邻NN间期差值的均方根(rMSSD)显著低于对照组[(82.3±29.0)ms比(139.4±40.2)ms;(75.0±27.4)ms比(130.3±43.9)ms;(29.9±14.9)ms比(57.3±14.4)ms;(19.8±10.9)ms比(29.5±9.4)ms](P＜0.01或＜0.05).甲亢组总功率(TP)、高频功率(HF)、低频功率(LF)和极低频功率(VLF)显著低于对照组[(566.1±573.2)ms2/Hz比(1894.2±984.3)ms2/Hz、(68.1±88.9)ms2/Hz比(232.7±155.5)ms2/Hz、(127.4±163.0)ms2/Hz比(551.3±390.6)ms2/Hz、(330.3±300.6)ms2/Hz比(1073.2±570.2)ms2/Hz](P＜0.01).短时频域分析甲亢组VLF在全天大多数时间均显著高于对照组(P＜0.05),LF主要在白天显著高于对照组(P＜0.05),HF在全天散在时间高于对照组(P＜0.05);两组LF/HF在全天绝大多数时间差异无统计学意义(P＞0.05).结论 甲亢患者心脏变时性低,交感神经张力在全天均增高,而迷走神经张力虽有相应增高,但以白天增高为主,夜间接近正常水平.

Abstract：

Objective To investigate the circadian change of autonomic nervous system in hyperthyroidism (HT) patients. Methods Recording 24 h dynamic electrocardiography from 33 HT patients( HT group) and 35 controls (control group). The cardiac autonomic nervous function was evaluated by the time domain and frequency domain analysis of heart rate variability( HRV). Results Comparing with control group, the SDNN, SDANN, ASDNN and rMSSD were significantly lower in HT group[ (82.3 ± 29.0)ms vs. (139.4±40.2 ) ms, ( 75.0 ± 27.4) ms vs. ( 130.3 ± 43.9) ms, (29.9 ± 14.9 ) ms vs. (57.3 ± 14.4) ms,( 19.8 ± 10.9 ) ms vs. (29.5 ± 9.4) ms ] (P ＜ 0.01 or ＜ 0.05 ), the long term total power (TP), high frequency (HF), low frequency (LF) and very low frequency (VLF) were significantly lower in HT group [ (566.1±573.2) ms2/Hz vs. ( 1894.2 ± 984.3)ms2/Hz, (68.1 ± 88.9 ) ms2/Hz vs. (232.7 ± 155.5 ) ms2/Hz, ( 127.4 ±163.0) ms2/Hz vs. (551.3 ± 390.6) ms2/Hz, (330.3 ± 300.6) ms2/Hz vs. (1073.2 ± 570.2) ms2/Hz] (P ＜0.01 ). Comparing with control group, short term VLF was higher in HT group during most time in 24 hours (P＜ 0.05 ). Short term LF was higher in HT group mainly in day time (P＜ 0.05 ). Short term HF was higher in HT group occasionally in the whole day (P＜0.05). Short term LF/HF didn't show significant difference between HT group and control group at most time points (P＞0.05).Conclusion In HT patients, cardiac chronotropic property is impaired, sympathetic activity increases in whole day, vagal activity increases correspondently but the increase in day is more marked than that in night.     

不同体位短臂离心机暴露时心血管及前庭功能的改变

目的 通过观察和比较不同体位下短臂离心机暴露所引起的心血管及前庭功能反应,进一步明确短臂离心机暴露下体位因素对心血管和前庭功能的影响. 方法 10名健康男性,依次进行75°、45°、15°后倾体位的短臂离心机暴露,且每体位先后进行2 G、3 G(足水平)人工重力暴露;采用便携式无创逐跳血压监测仪(Portapres)全程监测,并记录受试者血压、心率,通过Beatscope分析软件计算心脏泵血功能和总外周阻力;同时进行前庭功能评价,比较不同体位短臂离心机暴露对心血管、前庭系统的影响. 结果 2 G、3 G短臂离心机分别暴露时,15°体位下6名受试者出现严重运动病症状被迫终止试验;75°和45°两种体位下受试者血压、心率较基础值增高(F=2.79～16.44,P<0.05);心输出量则无显著变化.3 G暴露75°和45°两种体位时,每搏量显著降低(F=2.25、8.35,P<0.05).3 G暴露45°体位时总外周阻力较基础值增高(F=2.61,P<0.05);相同G值短臂离心机暴露时,75°体位下心血管功能变化较45°体位差异无统计学意义,而前庭功能评分则随着体位角度的减小而逐渐增高,15°体位下评分较45°和75°体位增高,差异有统计学意义(P<0.05). 结论 短臂离心机暴露时,45°和75°两种体位对心血管功能的影响无统计学意义,但不同体位对前庭功能的影响却差异较大.暴露体位越趋近于坐位,引起的运动病程度越重. Abstract： Objective To investigate the changes of human cardiovascular and vestibular functions when exposed to the artificiaI gravity generated by short-arm centrifuge with different body positions.Methods Ten healthy male volunteers were exposed to the artificial gravity at three different body positions:foot towards to the radial direction off the rotation center respectively with 75°,45°and 15°back tilting.Each position underwent on short-arm centrifuge with two sessions that were at 2 G and 3 G (at foot level) respectively.Beat-by-beat arterial blood pressure (BP) and heart rate (HR) were measured before and during the experiment by means of Portapres and calculated parameters,such as stroke volume (SV),cardiac output (CO) and total peripheral resistance (TPR),were obtained by Beatscope software.A subjective scoring was taken for assessing vestibular sensations. Results Six of 10 subjects with 15°posture were terminated both in 2 G and 3 G exposure due to their serious motion sickness symptoms.Comparing to the measurements before exposure,subjects with 45°and 75°posture showed significant increased BP and HR (F=2.79 to 16.44,P<0.05) but SV (F=2.25 or 8.35,P<0.05) while CO had no obvious change.Comparing to the measurements before exposure,subjects with 3 G (45°posture) showed significant incleased TPR (F=2.61,P<0.05).3 G exposure resulted in higher HR than that in 2 G.No significant changes of BP,HR,CO,SV and TPR were found between 45°and 75°postures under same exposure.The scores of vestibular assessment showed increased tendency with the decreased tilt angle.Significantly higher scores were got for 15°posture exposures comparing to others and indicated stronger vestibular stimuli.Conclusions The results suggested that the smaller tilted angle posture would result in mole serious vestibular symptoms.     

60天头低位卧床期间心功能的变化及振动和中药的对抗作用

目的 通过观察和比较60 d头低位（HDT）卧床期间振动和中药对心脏功能的影响,旨在进一步明确不同对抗方式对失重不良影响的对抗效果。方法 21名健康男性被试者,随机分为对照组、振动组和中药组,每组7人。对照组仅-6°HDT卧床60 d,口服安慰剂; 振动组和中药组在HDT卧床期间分别进行阻抗振动锻炼和口服太空养心丸。卧床前、卧床30、60 d测量心脏泵血、收缩功能。结果 对照组每搏量（SV）和心排出量（CO）在卧床30 d较卧床前显著降低(P<0.05),在60 d进一步降低(P<0.05),TPR在卧床60 d显著升高(P<0.05);振动组SV和CO在卧床60 d较卧床前显著降低(P<0.05),总外周阻力（TPR）显著升高(P<0.05);中药组在卧床期间上述指标的变化均未达到显著水平。3组射血前期与左室射血时间的比值(PEP/LVET)、等容收缩时间与左室射血时间的比值(ICT/LVET)在卧床60 d较卧床前均显著增加(P<0.05);中药组PEP/LVET和ICT/LVET在卧床60 d较对照组和振动组均显著降低(P<0.05)。结论 60 d头低位卧床可引起心脏泵血和收缩功能显著降低。在卧床期间服用中药可明显改善心脏泵血和收缩功能,而振动锻炼对心脏泵血和收缩功能有一定改善作用。     

不同体位短臂离心机暴露时心血管及前庭功能的改变

Objective To investigate the changes of human cardiovascular and vestibular functions when exposed to the artificiaI gravity generated by short-arm centrifuge with different body positions.Methods Ten healthy male volunteers were exposed to the artificial gravity at three different body positions:foot towards to the radial direction off the rotation center respectively with 75°,45°and 15°back tilting.Each position underwent on short-arm centrifuge with two sessions that were at 2 G and 3 G (at foot level) respectively.Beat-by-beat arterial blood pressure (BP) and heart rate (HR) were measured before and during the experiment by means of Portapres and calculated parameters,such as stroke volume (SV),cardiac output (CO) and total peripheral resistance (TPR),were obtained by Beatscope software.A subjective scoring was taken for assessing vestibular sensations. Results Six of 10 subjects with 15°posture were terminated both in 2 G and 3 G exposure due to their serious motion sickness symptoms.Comparing to the measurements before exposure,subjects with 45°and 75°posture showed significant increased BP and HR (F=2.79 to 16.44,P<0.05) but SV (F=2.25 or 8.35,P<0.05) while CO had no obvious change.Comparing to the measurements before exposure,subjects with 3 G (45°posture) showed significant incleased TPR (F=2.61,P<0.05).3 G exposure resulted in higher HR than that in 2 G.No significant changes of BP,HR,CO,SV and TPR were found between 45°and 75°postures under same exposure.The scores of vestibular assessment showed increased tendency with the decreased tilt angle.Significantly higher scores were got for 15°posture exposures comparing to others and indicated stronger vestibular stimuli.Conclusions The results suggested that the smaller tilted angle posture would result in mole serious vestibular symptoms.     

2型糖尿病动脉硬化与血管内皮功能的关系

高血糖、高血压、脂代谢紊乱、氧化应激、凝血-纤溶系统功能失调等多种危险因素参与了糖尿病血管并发症的发生和发展。脉搏波传导速度(PWV)作为独立于其他心血管疾病危险因素之外的又一重要危险因素,是反映动脉硬化的实用指标[1]。大量研究表明,血管内皮功能异常是2型糖尿病(T2DM)血管并发症的始发因素[2]。本研究检测了40例新诊断T2DM患者的     

间断性短臂离心机+Gz暴露联合运动锻炼对心血管自主神经调节功能的影响

目的 利用短臂离心机进行梯度G值联合运动负荷锻炼,观察间断性锻炼3周后人体心血管自主神经调节功能的变化.方法 8名健康青年男性间断进行离心机梯度G值(1～2 G)暴露联合30 W运动负荷锻炼,每天30 min,持续3周.记录心电图和逐跳连续血压,运用自回归谱分析法得到心率变异性(HRV)与收缩压变异性功率谱.锻炼前后进行头高位倾斜联合下体负压测试,观察立位应激时心血管功能变化.结果 在卧位休息时,锻炼3周后被试者HRV的低频与高频比值较锻炼前显著下降(P＜0.05),收缩压变异性的低频功率较锻炼前显著增加(P＜0.05).在头高位倾斜联合下体负压实验时,锻炼后被试者心率较锻炼前显著下降(P＜0.05),总外周阻力显著增加(P＜0.05),每搏量呈增加的趋势.结论 离心机+Gz暴露联合30 W运动锻炼3周可以增加平卧位心脏迷走神经与外周血管交感神经活动水平,增强立位应激时血压调节能力,提高了心血管功能储备.     

振动锻炼和太空养心丸对60 d头低位卧床脑血流的影响

目的 通过观察和比较60 d头低位(HDT)卧床期间振动锻炼、中药太空养心丸对脑血流的影响,进一步明确不同对抗方式对失重不良影响的对抗效果. 方法 21名健康男性志愿者,随机分为对照组、振动组和中药组3组,每组7人.对照组仅-6°HDT卧床60 d,口服安慰剂;振动组和中药组在HDT卧床期间分别进行阻抗振动锻炼和口服太空养心丸.卧床前、卧床第30天、第60天测量右侧大脑中动脉的血流速度. 结果 对照组的收缩期血流速度(Vs)在卧床第30天较卧床前显著降低(t=3.44,P<0.05),并且在第60天进一步降低t=5.07,P<0.01);舒张期血流速度(Vd)、平均血流速度(Vm)在卧床第60天显著降低(t=2.61、7.20,P<0.05).振动组的Vs在卧床第30天显著降低(t=2.49,P<0.05),并且在卧床第60天进一步降低(t=3.49,P<0.01);中药组Vs、Vd和Vm有降低趋势,但未达显著水平. 结论 60d头低位卧床可引起大脑中动脉血流速度显著降低.卧床期间服用太空养心丸对改善脑血流有一定作用,而振动锻炼则对脑血流影响不大.