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1.
马庆久  石景森  要秀  邱随民  罗健 《医学争鸣》2002,23(21):1926-1928
目的 探讨耳穴脉冲电刺激治疗胆石症 ,胆绞痛的机制 .方法 选用 15条成年杂种犬 ,进行耳穴体表脉冲刺激与缩胆素 (CCK)对在体狗胆囊张力 ,Oddi括约肌张力及肌电活动影响的对比研究 .结果 耳穴脉冲电刺激对胆囊张力无明显影响 [(1.2 7± 0 .2 6 ) k Pa与 (1.2 4± 0 .2 2 ) k Pa,P<0 .0 5 ],CCK注射液能明显提高胆囊张力 [(1.2 7± 0 .2 6 ) k Pa与 (1.91± 0 .39) k Pa,P<0 .0 5 ],CCK注射液能明显降低Oddi括约肌张力 [(2 .2 4± 0 .5 5 ) k Pa与 (1.5 8± 0 .5 6 ) k Pa,P>0 .0 5 ]及肌电活动 .结论 耳穴脉冲电刺激同 CCK一样 ,均对 Oddi括约肌的张力有显著的降低作用 ,并减少 Oddi括约肌的肌电峰电位爆发波的频率与电压值 ,推测其对胆绞痛有治疗作用 ,并有助于胆结石的排石过程 .  相似文献   
2.
本文报道了大鼠十二指肠电活动在运动疲劳前后的数值。结果表明:在运动疲劳后,快波、慢波振幅明显增加,而其频率却减少;Ⅰ相缩短,Ⅱ相延长,Ⅲ相、Ⅳ相及IDMEC周期无显著变化;并在运动疲劳后9.7±2.4min内出现不规律的食后型的电活动。这些改变可了解运动疲劳对消化系统的影响。  相似文献   
3.
目的:探讨胃排空改变以及胃窦平滑肌电节律紊乱在胆汁反流性胃炎发病中的可能机制。方法:对59例有慢性上消化道症状的慢性胃炎病人,根据胃镜下可见显著胆汁反流,胃液呈深黄色或深绿色,胃液pH≥3.0,甘胆酸浓度>58μg/ml,胃粘膜病理积分>9,判断为病理性胆汁反流(部分病人经:显象进一步证实)。胃镜下未见胆汁反流,胃液清亮,其余指标均未达上述标准者判断为非胆汁反流性。选出18例胆汁反流性胃炎病人(BRG组)和17例非胆汁反流性胃炎病人(NRG组),上述检查正常的10名健康志愿者(HC组)作为对照受检者进食一份双核素标记的标准餐,用照相机以1帧/2分钟连续动态照相120分钟,部分受试者又在空腹时检测胃窦肌电。结果:BRG组有明显的固、液体双相排空延迟,以固相延滞期(SLP)延长较为突出,而固体半排空时间(HSET)延长在很大程度上受到SLP延长的影响:NRG组仅有HSET显著延长。进一步胃电检测结果表明,各组间平均慢渡频率(MSWF)无显著性差异,出现胃电节律失常(DRM)在各组的分布为HC组1/7、NRG组3/10和BRG组7/13,严重程度BRG>NRG>HC。结论:胆汁反流性胃炎者有较严重的胃窦功能不良,且胃肌电可予进一步证实,胃底和十二指肠动力异常也可能与胆汁反流性胃炎的发病有关。  相似文献   
4.
Aspirin has antisecretory and ulcerogenic properties in the gastrointestinal tract. The aim of this study was to determine the effects of acetylsalicylic acid (ASA) on the electrical and mechanical activity of the ileum in anesthetized New Zealand White rabbits. Ileal electromechanical activity was recorded from serosal electrodes and a miniature intraluminal balloon. Thirty minutes after injection of ASA (30, 60 and 100 mg/kg intravenous) significant and dose-dependent increases in the percentage of slow waves with action potentials were observed when compared with saline-injected animals. The onset of action potentials correlated with phasic increases in intraluminal pressure, indicating the onset of circular muscle contractions. Injection of 15 mg/kg ASA, sodium salicylate (100 mg/kg intravenous) or saline had no effect on baseline action potential activity. Prostaglandin E 2 (PGE 2)(5 and 10 g/kg intravenous) significantly increased slow-wave frequency and decreased ASA-induced action potential activity. This study demonstrates that (1) ASA, but not sodium salicylate, stimulates phasic ileal action potential and contractile activity and (2) in ASA-treated animals, PGE 2 produces differential effects on in vivoslow-wave frequency and action potential activity.  相似文献   
5.
利用表面肌电信号评价肌肉疲劳的方法   总被引:7,自引:0,他引:7  
表面肌电信号分析是评价局部肌肉疲劳有效的工具。过去由于受信号处理技术的限制,对肌肉疲劳的评价仅局限于等长、恒力收缩。由于适合于非平稳信号分析的频谱估计技术的发展,使得动态收缩条件下的肌肉疲劳评价得以实现,在工效学、康复医学和运动医学等方面开启了新的应用领域。本文论述了利用表面肌电信号评价肌肉疲劳,特别是在肌肉动态收缩期间评价肌肉疲劳的方法,为进一步探讨肌肉疲劳的发生机制提供理论依据。  相似文献   
6.
  1. The effects induced by 5-hydroxytryptamine (5-HT) on gastrointestinal myoelectric activity in conscious sheep were recorded through electrodes chronically implanted and analysed by computer. The 5-HT receptors and the cholinergic neuronal pathways involved in these actions were investigated.
  2. The intravenous (i.v.) administration of 5-HT (2, 4 and 8 μg kg−1 min−1, 5 min) induced an antral inhibition concomitant with a duodenal activity front that migrated to the jejunum, followed by a period of intestinal inactivity. This myoelectric pattern closely resembled that observed in the phases III and I of the migrating myoelectric complex (MMC) in sheep. The 0.5 μg kg−1 min−1 dose evoked the same pattern in only two out of the six animals used. Likewise, the 1 μg kg−1 min−1 dose similarly affected four of the six animals. In addition, a transient stimulation was observed in the antrum and jejunum when the two highest doses were used.
  3. The 5-HT1 antagonist, methiothepin (0.1 mg kg−1), the 5-HT2 antagonists, ritanserin (0.1 mg  kg−1) and ketanserin (0.3 mg  kg−1), the 5-HT3 antagonists, granisetron (0.2 mg kg−1) and ondansetron (0.5 mg kg−1), as well as the 5-HT4 antagonist, GR113808 (0.2 mg kg−1), did not modify the spontaneous gastrointestinal myoelectric activity. However, the cholinoceptor antagonists, atropine (0.2 mg kg−1) and hexamethonium (2 mg kg−1), inhibited gastrointestinal activity.
  4. When these antagonists were injected i.v. 10 min before 5-HT (2 or 4 μg kg−1 min−1, 5 min), only GR113808, atropine and hexamethonium were able to modify the 5-HT-induced actions, all of them being completely blocked by the three antagonists.
  5. Our data show that 5-HT initiates a MMC-like pattern in the gastrointestinal area in sheep through 5-HT4 receptors. Furthermore, these actions are mediated by cholinergic neural pathways involving muscarinic and nicotinic receptors. However, our results do not indicate a role for either 5-HT1, 5-HT2 or 5-HT3 receptors in the 5-HT-induced effects.
  相似文献   
7.
大黄对淤胆型大鼠胃肠消化间期MMC的影响及利胆机制探讨   总被引:2,自引:0,他引:2  
目的 从胃肠电生理探讨大黄治疗胆汁淤积的机制.方法 在大鼠的胃窦、十二指肠及空肠埋置3对银丝电极,采用α-异硫氰酸萘酯建立大鼠急性肝内胆汁淤积模型.观察大黄对胃肠消化间期移行性复合肌电活动(MMC)及胃肠组织中一氧化氮合酶(NOS)表达的影响.结果 模型组早期MMC节律完全消失,随后逐渐恢复,但恢复时间较正常组晚且周期明显延长,胃肠NOS的表达明显增多.大黄组MMC节律恢复时间较模型组早,周期无明显改变,胃肠NOS的表达也比模型组显著减少(P<0.05).结论 大黄通过增加胆汁排泌,促进胆汁淤积大鼠胃肠MMC的恢复,从而达到清热解毒、利胆退黄的效应.  相似文献   
8.
枳实对大鼠小肠电活动影响的下丘脑作用机制研究   总被引:1,自引:0,他引:1  
目的观察枳实对在体大鼠小肠电活动的影响,探讨其作用与下丘脑内脑肠肽胆囊收缩素(CCK)、生长抑素(SS)的相关性。方法采用消化道腔外电极记录法观察枳实组与生理盐水组移行性综合肌电(MMC)周期时程、活动期/周期比例、活动期每分钟快波数的变化;采用免疫组织化学法结合显微图像定量分析扫描系统检测下丘脑背内侧核(DMH)、腹内侧核(VMH)、下丘脑外侧区(LHA)CCK的相对含量,以及下丘脑VMH、LHA、室旁核(PVN)SS的相对含量。结果枳实组与生理盐水组比较MMC周期缩短、活动期/周期比例增大、活动期每分钟快波数增加,差异有显著性;与生理盐水组及空白对照组比较枳实组DMH、VMH、LHA的CCK阳性神经元表达降低;VMH、LHA、PVN的SS阳性神经元表达增高,与生理盐水组及空白对照组比较差异有显著性。结论枳实对大鼠小肠电活动有兴奋作用,这种兴奋作用可能与下丘脑内的CCK、SS有关。  相似文献   
9.
Rikkunshi-to (TJ-43), a gastroprotective herbal medicine, has been used for the symptomatic relief of adult patients with dyspepsia. However, its mechanism has yet to be fully elucidated. The aim of this study is to evaluate the effect of TJ-43 on the gastric myoelectric activity in post-operative dyspeptic patients, whose symptoms persisted for over 1 year after gastrointestinal surgery. Electrogastrography (EGG) recordings were performed to calculate the biomechanical parameters on the dominant peak frequency (DPF). Eight pediatric patients with dyspeptic symptoms after gastrointestinal surgery were examined and six age-matched children without any dyspeptic symptoms were used as controls, and they were compared with nine age-matched children without any dyspeptic symptoms after gastrointestinal surgery as subcontrols. All patients exhibited symptomatic relief after the administration of TJ-43, and the mean symptom score decreased significantly after the treatment of TJ-43 over a 1-month period (P<0.0001). The variability index (VI) and the percentage of normal waves (PNW) were calculated as irregularity parameters of DPF. The power ratio (PR) was calculated as a parameter of the gastric contractile activity. There were no significant differences in the VI and PNW between the controls and patients during the postprandial state after therapy, even though significant differences existed regarding those parameters between the controls and patients before the therapy. There were no significant differences in the DPF, VI, and PNW between the controls and subcontrols. Furthermore, PR exhibited a significant increase after therapy (P<0.05). However, there was a significant difference in the PR between the controls and subcontrols (P<0.05). Postprandial dip was observed in all control subjects, eight patients in the subcontrols, and two patients after administration of TJ-43, respectively. An abnormal gastric electrical activity therefore seems to be an important factor in the pathophysiology of post-operative dyspeptic children. The coordinating and stimulating effect of TJ-43 on the gastric myoelectric activity therefore seems to play an important role in the reduction of dyspeptic symptoms.  相似文献   
10.
Background Abnormalities in gastrointestinal motility have been reported in adult patients with advanced liver disease. However, there have so far been no reports on the gastric myoelectric activity in post-operative patients with biliary atresia (BA).Aim The purpose of this study was to evaluate the gastric myoelectric activity in post-operative patients with BA in relation to liver fibrosis.Patients and methods Twenty-one post-operative patients with BA, consisting of 6 boys and 15 girls with a mean age of 8.0 years and 6 healthy children (control group) were included in the study. The gastric myoelectric activity was measured by electrogastrography (EGG). The patients with BA were divided into two groups according to the serum hyaluronic acid (HA) level as a marker of liver fibrosis: the fibrotic group (FG, n=11), HA>50 ng/ml and the non-fibrotic group (NF, n=10), HA 50 ng/ml. All recorded data were spectrally analyzed and any parameters related to changes in the dominant peak frequency (DPF) and its power were investigated. Furthermore, the gastrointestinal symptom scores (GSS) were calculated in patients with dyspeptic symptoms according to the degree of advanced liver fibrosis.Results The results showed that 1) the postprandial DPF in the FG tended to be higher than that in the NFG (p=0.051), 2) the postprandial variability index of the DPF in the FG and NFG were significantly higher than those in the controls (p<0.05), and 3) the preprandial percentage of normal waves (PNW) in the FG tended to be lower than that in the controls (p=0.089). The postprandial PNWs in the FG and NFG were significantly lower than those in the controls (p<0.05). Especially, the postprandial PNW in the FG was significantly lower than that in the NFG (p<0.05). 4) The power ratio in the FG and NFG were significantly lower than those in the controls (p<0.05), and 5) the GSSs in the FG were significantly higher than those in the NFG (p<0.05).Conclusions The gastric myoelectric activity appeared to be disturbed in BA patients associated with portal hypertension and neurohormonal changes due to liver fibrosis.  相似文献   
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