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21.
右归饮择时使用对肾阳虚大鼠生长激素昼夜节律的影响 总被引:1,自引:0,他引:1
目的 探讨右归饮择时用药在肾阳虚证治疗中的意义。 方法 采用放免法 ,以肾阳虚大鼠血清生长激素为指标 ,观察右归饮择时用药的疗效。结果 右归饮择时用药对肾阳虚大鼠症状的改善有一定作用 ,并以卯时用药效果较好。结论 右归饮治疗肾阳虚证应当提倡择时用药。 相似文献
22.
目的 研究重度充血性心力衰竭患者血流动力学的昼夜节律改变.方法 选择2005年12月至2006年6月在南京中医药大学无锡附属医院心内科住院的重度充血性心力衰竭患者120例为心衰组,同期门诊体检的无心血管疾病者20名为对照组,采用生物阻抗法每小时1次动态监测心率(HR)和每搏输出量(SV).结果 心衰组与对照组HR、SV均存在昼夜节律,但分布规律存在差异,心衰组HR明显快于对照组(P<0.5),而SV明显低于对照组(P<0.05);对照组HR与SV呈正相关(P<0.01),而心衰组HR与SV总体上也呈正相关(P<0.01),但在凌晨100~400之间,两组HR与SV分布曲线明显不同,心衰组HR与SV分布曲线出现分离现象,HR下降而SV上升,呈负相关(P<0.01),而同时段的对照组HR与SV则仍呈正相关(P<0.01).结论 重度充血性心力衰竭患者HR和SV分布的昼夜节律受损,在凌晨100~400之间,HR与SV分布趋势存在分离现象. 相似文献
23.
Infusion of 1 μg of carbachol, a potent cholinergic agonist, into the lateral septum of the urethane-anaesthetized rat systematically caused the induction of clear-cut hippocampal theta (θ). However, infusion of an equivalent amount of the drug into the hippocampus, close to the recording electrode, failed to induce θ in 50% of the animals and produced a mixture of θ waves and desynchronized activity, resulting in atypical EEG patterns, in the remaining subjects. Both carbachol EEG effects were blocked by intraseptal infusion of the antimuscarinic agent, atropine. Our data demontrate that muscarinic receptors in the septum are predominent sites for cholinergic agonist-antagonist action capable of generating or suppressing hippocampal θ in the rat. They also indicate that intraseptal cholinergic mechanisms play an important role in the initiation and generation of this rhythm. 相似文献
24.
Twenty-four-hour ambulatory blood pressure profiles in pediatric patients after renal transplantation 总被引:2,自引:2,他引:0
Nicolaus Lingens Eva Dobos Klaus Witte Christopher Busch Björn Lemmer Günther Klaus Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(1):23-26
Ambulatory blood pressure monitoring was applied in 27 pediatric patients aged 6.3 – 24.3 (median 15.0) years who had been
transplanted 1.5 – 8.4 years previously. Daytime values were compared with the mean of 10 concomitant casual blood pressure
recordings. At the time of the study, antihypertensive drugs were given to 17 patients. Inulin clearance ranged from 18 to
116 (median 66) ml/min per 1.73 m2. Ambulatory blood pressure monitoring confirmed hypertension or normotension determined by casual blood pressure measurements
in 63% of patients. The physiological nocturnal dip in blood pressure was attenuated or reversed in 8 of 27 patients. It was
reduced in all 3 patients with renal artery stenosis of the graft, in 3 of 4 patients with chronic rejection, in the only
patient with recurrent focal segmental glomerulosclerosis, and in 1 of 6 patients with past acute rejection. The dipping was
not related to inulin clearance. In conclusion, casual blood pressure measurements do not accurately reflect blood pressure
in pediatric patients transplanted more than 1.5 years previously. A reduced nocturnal dip in blood pressure may indicate
an underlying renovascular or renoparenchymal pathology. Ambulatory blood pressure monitoring should regularly be applied
in patients with renal transplants.
Received May 23, 1995; received in revised form June 18, 1996; accepted June 20, 1996 相似文献
25.
Pacemaker Current if. Since the hyperpolarization-activated current, if, was originally associated with the diastolic depolarization phase of action potential in the sinoatrial (SA) node in 1979, its central role in the generation and control of pacemaker activity has become increasingly clear through a series of experimental findings, some of which have substantially modified the pre-existing theories of cardiac pacemaking and its modulation by the autonomic transmitters. Thus, the pacemaker current of Purkinje fibers, formerly described as a deactivating pure potassium (K) current, was found to be in fact, like the nodal if, inward and activating on hyperpolarization. Furthermore, in SA node cells, as well as mediating rhythm acceleration induced by catecholamines, if was found to underlie the slowing effect of low acetylcholine (ACh) concentrations, in contrast with the generally accepted hypothesis that activation of a K conductance is the main process responsible for cardiac slowing. A final, atypical property of if recently demonstrated concerns the activating action exerted on if by intracellular cAMP. Unlike that on other voltage-gated, cAMP-modulated cardiac channels, this action is independent of phosphorylation and involves a direct binding of cAMP to if channels. (J Cardiovasc Electrophysiol, Vol. 3, pp. 334–344, August 1992) 相似文献
26.
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
27.
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
28.
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
29.
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
30.
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