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31.
血压变异与心率变异及心电异常相关性分析 总被引:1,自引:0,他引:1
目的:研究血压变异(BPV)与心率变异(HRV)及心电图(ECG)异常相关性,方法:对157例未经治疗的早期高血压患者及167例未服过影响血压及心率药物的正常人,进行BPV、HRV及ECG异常的相关分析,各种数据在同一时刻得到,结果:当血压昼夜节律消失(非杓型),BPV及HRV不正常,ECG异常明显高于其他组,当高血压患者血压昼夜节律存在时HRV各项指标接近正常,ECG异常率较低,HRV降低与血压负荷升高呈明显正相关,与心电异常也呈明显正相关,结论:对高血压治疗的目的。不仅仅是降压,还应尽量恢复昼夜血压的规律性,降低夜间血压负荷,调节植物神经功能,对于血压正常的患者。血压昼夜节律消失也应投以关照给予植物神经功能调节,达到或降低靶器官损伤或延缓靶器官损害的目的,提高患者的生活质量。 相似文献
32.
Minoru Hasegawa Maki Goto Itsuki Oshima Shizufumi Ebihara 《Neuroscience and biobehavioral reviews》1995,18(4):537-540
Circadian rhythms of pineal melatonin release were measured in free-moving pigeons, Japanese quails, and chickens under light-dark cycles followed by constant dim light. Although melatonin levels differed among individual birds, circadian rhythms of melatonin were observed in all of them. Using this technique, we could examine phase shifts of melatonin rhythms and suppression of melatonin release by photic stimulation in pigeons. We could also examine effects of norepinephrine infusion on melatonin release. These results indicate that microdialysis is useful for the study of pineal melatonin rhythms in birds. 相似文献
33.
为提高肺心病心律失常的临床疗效,采用中药清肺化痰活血剂配合抗菌素及氧疗法对40例肺心病并发心律失常患者进行了治疗观察,同时与单纯使用抗菌素及氧疗法治疗的40例患者进行对照。临床以心电图改善情况为观察指标,结果两组有效率分别为87.5%和67.5%。Ridit分析结果表明,治疗组疗效明显优于对照组,经显著性检验,两组差异显著(P<0.05)。 相似文献
34.
The purpose of this study was to determine if aging affects the circadian rhythm of serum cortisol. Female beagle dogs belonging to three age groups were used: adult (3.3 ± 0.6 (SD) years), old (12.1 ± 0.3 years), and puppies (8.4 ± 0.2 weeks). Blood samples were collected by cephalic or jugular venipuncture at 3-h intervals during three 24-h periods and analyzed for total serum cortisol concentrations by radioimmunoassay. The circadian rhythm was present in the serum cortisol of adult animals, but no significant changes during a 24-h period could be detected in the old animals. No circadian rhythm in serum cortisol was present in the puppies. It is concluded that the circadian rhythm in plasma cortisol is disrupted in old animals and is not yet developed in puppies. 相似文献
35.
应用食道心房调博缩测定健康小儿窦房结功能,以了解西宁地区正常数值与平原地区进行对比。选择27例健康小儿,将F6二级电极导管从鼻腔送入,定位地食道心电图最大正负双相P波处,采用苏州东方电子仪器厂生产的DF-3A型心脏电生理治疗仪进行检查,从而作出诊断。 相似文献
36.
Zehr EP Haridas C 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,149(2):260-266
Stimulation of cutaneous nerves innervating the hand evokes prominent reflexes in many arm muscles during arm cycling. We
hypothesized that the mechanisms controlling reflex modulation during the rhythmic arm swing of walking would be similar to
that documented during arm cycling. Thus, we expected cutaneous reflexes to be modulated by position in the walking cycle
(phase dependence) and be different when walking compared to contraction while standing (task dependence). Subjects performed
static postures similar to those occurring during walking and also walked on a treadmill while the superficial radial nerve
was electrically stimulated pseudorandomly throughout the step cycle. EMG was recorded bilaterally from upper limb muscles
and kinematic recordings were obtained from the elbow and shoulder joints. Step cycle information was obtained from force-sensing
insoles. Analysis was conducted after averaging contingent upon the occurrence of stimulation in the step cycle. Phase-dependent
modulation of cutaneous reflexes at early (~50–80 ms) and middle (~80–120 ms) latencies was observed. Coordinated bilateral
reflexes were seen in posterior deltoid and triceps brachii muscles. Task dependency was seen in that reflex amplitude was
only correlated with background EMG during static contraction (75% of comparisons for both early and middle latency reflexes).
During walking, no significant relationship between reflex amplitude and background EMG level was found. The results show
that cutaneous reflex modulation during rhythmic upper limb movement is similar to that seen during arm cycling and to that
observed in leg muscles during locomotion. These results add to the evidence that, during cyclical movements of the arms and
legs, similar neural mechanisms observed only during movement (e.g. central pattern generators) control reflex output.
Electronic Publication 相似文献
37.
The present piece of research studied the spontaneous alpha rhythm of the human brain by combining the use of a whole-cortex neuromagnetometer and Magnetic Resonance Imaging. Single trials of spontaneous brain activity were recorded from ten human subjects asked to rest, with their eyes either closed or open, in relaxed wakefulness. MEG measurements were conducted over a period of one and a half years. The replicability of the results was confirmed for eight subjects out of ten. For three subjects, the alpha rhythm did not show any reductions due to the opening of the eyes. Both field map pattern and location of the estimated source were persistently stationary during each of the bursts of oscillations of the alpha rhythm. Dipoles were concentrated in clusters, indicating the existence of several spatially distributed sources. The calcarine fissure, the parieto-occipital sulcus and the surrounding occipital and parieto-occipital areas were identified as cortical sites of the brain where the alpha rhythm may originate. For four subjects, the majority of the sources were located near or in the calcarine fissure, while for five subjects, they were located near or in the parieto-occipital sulcus and for the remaining subject they were equally divided between the two generation sites. 相似文献
38.
Rudolf Graf 《Pflügers Archiv : European journal of physiology》1980,386(2):173-179
In pigeons, we studied the diurnal variation of body temperatures and its dependence on the diurnal variations of shivering, vasomotor activity and panting in light-dark (LD) — conditions (1212 h, 1001 Lux) and in different, but for at least 24 h constant ambient temperatures.In low ambient temperatures (below thermoneutrality) shivering was reduced shortly after lights off (early dark phase), and it increased again some hours before lights on (late dark phase); the lower the ambient temperature, the larger the reduction of shivering and the shorter the time of reduction.Within thermoneutrality, the decrease ofT
b
in the early dark phase was associated with an increase of foot skin temperature, probably due to vasodilatation. Later-on foot skin temperature decreased again (vasoconstriction). The feet remained constricted even in the late dark phase, whenT
b
already increased.At higher ambient temperature (above thermoneutrality) vasodilatation persisted all over the 24 h, while in these conditions respiratory rate increased significantly after lights off.The described diurnal variations of thermoregulatory effector mechanisms are in agreement with the concept of an active adjustment of the body temperature rhythm.Supported by the Deutsche Forschungsgemeinschaft (SBF 114) 相似文献
39.
OBJECTIVE: We examined sleep, daytime sleepiness and the ability to stay awake during the day in patients affected with retinitis pigmentosa (RP), to further delineate the role of photoreceptors in the circadian cycle. METHODS: Twelve individuals diagnosed with RP (40 +/- 8 years) And 12 normally sighted healthy individuals (39 +/- 7 years) matched for age, body mass index (BMI) and sex were selected for the study. Participants had their sleep recorded on two consecutive nights and were monitored on the two following days. On the first day, their ability to stay awake and on the second, their sleep propensity were assessed using the Maintenance of Wakefulness Test (MWT) and the Multiple Sleep Latency Test (MSLT), respectively. Self-report measures were obtained using the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), and the Toronto Hospital Alertness Test (THAT). RESULTS: Subjective daytime sleepiness (ESS: 9 +/- 5 vs. 6 +/- 4, P=0.053) and objectively measured sleep propensity (MSLT: 10 +/- 5 vs. 17 +/- 3 min, P < 0.000) were significantly higher in RP patients than controls, whilst their alertness (THAT: 29 +/- 9 vs. 38 +/- 7, P=0.016) and ability to stay awake (MWT: 21 +/- 9 vs. 29 +/- 2 min, P=0.006) were significantly reduced. Retinitis pigmentosa participants had more disturbed nighttime sleep, with significantly more awakenings (arousal index: 14 +/- 8 vs. 8 +/- 6 h, P=0.039), and tended to have less rapid eye movement (REM) sleep (19 +/- 5 vs. 22 +/- 3%, P=0.094). CONCLUSION: Patients with RP have increased daytime sleepiness, reduced alertness and more disturbed nighttime sleep of poorer quality than their normally sighted counterparts, suggesting an influence of photoreceptor degeneration on the circadian cycle. 相似文献
40.
摘除双侧眼球对大鼠视交叉上核节律性的影响 总被引:2,自引:0,他引:2
成年Wistar雌鼠57只,随机分为实验组30只,行双眼摘除术。对照组27只。术后4周将各组动物体重相近的每3只列为一个配伍组,分别在09:00~10:00、17:00~18:00、23:00~24:00三个时间处死。将含有视交叉上核的脑组织经固定、恒冷箱切片后,用免疫组化ABC法染色显示视交叉上核内含VIP或AVP的神经元,微机图像分析仪上测量光镜下这两种神经元的相对切面面积及平均免疫反应强度。结果:(1)对照组不同时间处死的动物VIP能神经元切面面积以23:00~24:00最大,09:00~10:00次之,17:00~18:00最小,呈昼夜节律变化,AVP能神经元也以23:00~24:00最大,但在09:00~10:00和17:00~18:00间差异无显著性;(2)摘除双眼后各时间组间VIP能神经元和AVP能神经元切面面积均不再显示显著性差异。提示实验组动物视交叉上核的这两种神经元功能活动的昼夜节律已发生改变;(3)实验组和对照组动物的VIP能神经元和AVP能神经元平均免疫反应强度在所测的三个时间中,均未见明显差异。 相似文献