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BackgroundLow-frequency stimulation (LFS, <5 Hz) has been proposed as an alternative option for the treatment of epilepsy. The stimulation pole, anode and cathode, may make different contributions to the anti-epileptic effect of LFS.ObjectiveTo determine whether electrode polarity influences the anti-epileptic effect of LFS at the kindling focus in amygdaloid kindling rats.MethodsThe effect of bipolar and monopolar (or unipolar) LFS at the amygdala in different polarity directions on amygdaloid kindling acquisition, kindled seizures and electroencephalogram (EEG) were tested.ResultsBipolar LFS in the same direction of polarity as the kindling stimulation but not in the reverse direction retarded kindling acquisition. Anodal rather than cathodal monopolar LFS attenuated kindling acquisition and kindled seizures. Bipolar LFS showed a stronger anti-epileptic effect than monopolar LFS. Furthermore, anodal LFS (both bipolar and monopolar) decreased, while cathodal LFS increased the power of the EEG from the amygdala; the main changes in power were in the delta (0.5–4 Hz) band, which was specifically increased during kindling acquisition.ConclusionsOur results provide the first evidence that the effect of LFS at the kindling focus on amygdaloid kindling in rats is polarity-dependent, and this may be due to the different effects of anodal and cathodal LFS on the activity in the amygdala, especially on the delta band activity. So, It is likely that the electrode polarity, especially that for anodal current, is a key factor affecting the clinical effects of LFS on epilepsy.  相似文献   
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 目的 探讨淫羊藿甙对骨形态发生蛋白细胞信号通路Smad1、Smad5和Smad4表达的调节作用及促进成骨细胞增殖与分化的机制。方法 在体外分别用含淫羊藿甙0、10-9、10-8 和10-7 mol/L的条件培养液干预MC3T3-E1细胞。给药后第1天、2天和3天,分别应用四甲基噻唑蓝法绘制细胞生长曲线并计算细胞群体倍增时间,用速率分光光度法测定碱性磷酸酶含量,用RT-PCR和Western blot技术检测Smad1、Smad5、Smad4及骨钙素、Runx2、骨形态发生蛋白-2、骨保护素mRNA的表达,于细胞生长的第21天观察钙结节数量。结果 淫羊藿甙含量为10-8 mol/L时,MC3T3-E1细胞增殖能力最强,碱性磷酸酶活性和钙结节数量明显增加;淫羊藿甙作用细胞第1天、2天和3天时,10-8 mol/L组细胞Smad1、Smad5和Smad4 mRNA的表达量始终保持较高水平,第3天时10-9 mol/L和10-7 mol/L组表达明显减少;第2天时,10-8 mol/L组细胞Runx2、骨形态发生蛋白-2、骨保护素mRNA和骨钙素、Smad1、Smad5和Smad4蛋白表达明显增加。结论 淫羊藿甙通过直接刺激 MC3T3-E1细胞的骨形态发生蛋白-2、Runx2、Smad1、Smad5和Smad4的表达,且以表达水平同步增高的方式促进其成骨性分化。  相似文献   
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Aims: To determine the immediate and long‐term results of endoscopic drainage and necrosectomy for symptomatic pancreatic fluid collections. Methods: The data of 80 patients with symptomatic pancreatic fluid collections (mean diameter: 11.7 cm, range 3–20; pseudocysts: 24/80, abscess: 20/80, infected walled‐off necrosis: 36/80) referred for endoscopic management from October 1997 to March 2008 were analyzed retrospectively. Results: Endoscopic drainage techniques included endoscopic ultrasound (EUS)‐guided aspiration (2/80), EUS‐guided transenteric drainage (70/80) and non‐EUS‐guided drainage across a spontaneous transenteric fistula (8/80). Endoscopic necrosectomy was carried out in 49/80 (abscesses: 14/20; infected necrosis: 35/36). Procedural complications were bleeding (12/80), perforation (7/80), portal air embolism (1/80) and Ogilvie Syndrome (1/80). Initial technical success was achieved in 78/80 (97.5%) and clinical resolution of the collections was achieved endoscopically in 67/80 (83.8%), with surgery required in 13/80 (perforation: four; endoscopically inaccessible areas: two; inadequate drainage: seven). Within 6 months five patients required surgery due to recurrent fluid collections; over a mean follow up of 31 months, surgery was required in four more patients due to recurrent collections as a consequence of underlying pancreatic duct abnormalities that could not be treated endoscopically. The long‐term success of endoscopic treatment was 58/80 (72.5%). Conclusions: Endoscopic drainage of symptomatic pancreatic fluid collections is safe and effective, with excellent immediate and long‐term results. Endoscopic necrosectomy has a risk of serious complications. The underlying pancreatic duct abnormalities must be addressed to prevent recurrence of fluid collections.  相似文献   
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ObjectiveThis study was performed to determine the prevalence of chronic kidney disease (CKD) as well as its association with mid-term prognosis in patients with stable premature coronary artery disease (CAD) in a Chinese population.MethodsFive hundred and twelve patients from Jiangsu Province, China with stable, premature CAD were enrolled using an estimated glomerular filtration rate (eGFR) to determine the presence of CKD. The patients were then monitored over a two-year follow up during which major adverse cardiac events (MACEs) were recorded and analyzed.ResultsOne hundred and eighty-three patients (35.74%) were determined to have CKD. Having CKD was associated with a higher ratio of type 2 diabetes mellitus, multi-vessel disease, higher levels of fasting blood sugar and lower levels of left ventricular ejection fraction (all P < 0.05). Patients with CKD had significantly higher incidences of composite MACEs than the non-CKD group at the end of the two- (45.35% vs 30.72%, P = 0.001) but not one-year follow up (30.64% vs 25.32%, P = 0.209). Furthermore, as eGFR decreased, more MACEs occurred (all P < 0.05). Multivariate analysis confirmed that both CKD (P < 0.001) and multi-vessel disease (P < 0.001) are independent risk factors for MACEs.ConclusionChinese patients diagnosed with stable, premature CAD and CKD have more risk factors and worse two-year outcomes than those with only CAD.  相似文献   
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Background and Aim: Previous studies investigating the association between the glutathione S‐transferase Tl (GSTT1) null genotype and colorectal cancer (CRC) risk in the Asian population have reported controversial results. Thus, a meta‐analysis was performed to clarify the effect of the GSTT1 null genotype on CRC risk in the Asian population. Methods: A comprehensive study was conducted, and 12 case‐control studies were finally included, involving a total of 4517 CRC cases and 6607 controls. Subgroup analyses were performed by the sample size. Results: A meta‐analysis of all 12 studies showed that the GSTT1 null genotype was significantly associated with an increased CRC risk in the Asian population (odds ratio [OR] = 1.10, 95% confidence interval [CI] = 1.02–1.19, the P‐value of the OR [POR] = 0.02, the value of the heterogeneity analysis [I2] = 42%). A more obvious association was observed after the heterogeneity was eliminated by excluding one study (OR = 1.15, 95% CI: 1.06–1.25, POR = 0.001, I2 = 0%). This association was further identified by both subgroup analyses and a sensitivity analysis. Conclusions: This meta‐analysis suggests that the GSTT1 null genotype contributes to an increased colorectal cancer risk in the Asian population.  相似文献   
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