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1.
Background and objective: Myocardial infarction (MI) is a common critical disease of the cardiovascular system. The process of MI is often accompanied by the excessive activation of cardiac sympathetic nerves, which leads to arrhythmia. Resiniferatoxin (RTX) is a transient receptor potential vanilloid 1 (TRPV1), involved in the cardiac sympathetic afferent reflex. However, whether RTX can reduce the occurrence of arrhythmia and exert a cardioprotective effect by inhibiting the sympathetic reflex during MI is still unknown. Methods: The left anterior descending artery of cardiac was clamped to construct a model of MI. RTX (50 μg/ml) was used by epicardial application in MI rats. Ventricular electrophysiologic properties were continuously monitored by a body surface ECG. Yrosine hydroxylase (TH) and growth associated protein 43 (GAP43) were detected by Immunofluorescence staining. Connexin43 and transforming growth factor beta receptor 1 (TGF-β1) were detected by western blot. Norepinephrine (NE) and BNP levels in blood and tissue were determined by ELISA. Cardiac function was assessed by echocardiography. Results: The ERP, APD90, QRS, QT and the Tend-Tpeak intervals in MI rats were all prolonged, but decreased after RTX treatment (n = 3, P<0.05). In contrast, the RR interval was shortened in the MI group, but prolonged in the MI+RTX group (n = 3, P<0.05). RTX treatment significantly reduced ventricular arrhythmias after MI. TH- and GAP43-positive nerve densities and TGF-β1, and cx-43 protein expression were up-regulated in the MI group compared to the sham group, and they were decreased in the MI+RTX group compared to the MI group (n = 3, P<0.05). RTX can decrease serum and tissue NE and BNP levels (n = 3, P<0.05). RTX pretreatment significantly decreased heart rate, HW/BW ratio and LVIDS, and increased LVEF andLVFS values (n = 3, P<0.05). Conclusion: RTX improved cardiac dysfunction, ventricular electrophysiologic properties, and sympathetic nerve remodeling in rats with MI by inhibiting the excessive cardiac sympathetic drive.  相似文献   
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We propose a high order finite difference linear scheme combined with a high order bound preserving maximum-principle-preserving (MPP) flux limiter to solve the incompressible flow system. For such problem with highly oscillatory structure but not strong shocks, our approach seems to be less dissipative and much less costly than a WENO type scheme, and has high resolution due to a Hermite reconstruction. Spurious numerical oscillations can be controlled by the weak MPP flux limiter. Numerical tests are performed for the Vlasov-Poisson system, the 2D guiding-center model and the incompressible Euler system. The comparison between the linear and WENO type schemes, with and without the MPP flux limiter, will demonstrate the good performance of our proposed approach.  相似文献   
3.
杜玫洁  黄素芳  熊杰  储备 《护理学杂志》2022,27(10):110-113
以过渡期护理内涵为基础对文献进行干预措施内容提取,以干预时间点为标准对ICU转科患者家属迁移应激的过渡期护理措施进行综述,护理干预措施包括干预前准备、转科前干预、转科中干预、转科后干预,并总结护理干预效果评价,以期为临床护理人员开展相关实践提供具体参考,推进以家庭为中心的护理工作,改善临床护理质量。  相似文献   
4.
自2019年12月新型冠状病毒感染暴发以来,我国政府采取了严格的防控措施,国内疫情已得到初步控制,但形势依然严峻,境外多个国家也相继出现疫情。根据世界卫生组织的报告:截至2020年3月5日,全球共报告95333例确诊病例(其中我国累计报告确诊病例80565例),85个国家有确诊病例报告,中国将面临输入性病例的传播风险,这为防治我国儿童的疾病疫情提出了新的挑战[1]。在这次疫情中,与成人病例相比,儿童病例相对较少、症状轻、预后较好。目前国内病例数据显示,18岁以下儿童占所有报告病例的2.4%,尚无死亡病例报告[2]。  相似文献   
5.
目的 评价碳离子和质子治疗胰腺癌(PaC)的安全性和有效性。方法 检索数据库纳入碳离子和质子治疗PaC的临床研究,检索时间为自建库至2019年6月。两位研究者独立筛选文献、提取资料。采用STATA 12.0和MetaAnalyst Beta 3.13软件进行Meta分析。结果 共纳入8篇文献,包含459例PaC患者。效应模型Meta分析显示,碳离子和质子治疗PaC的2、3、5级胃肠道溃疡发生率分别为7%、2%、0;2、3、4级厌食症发生率分别为6%、3%、0;1、2年总生存率(OS)分别为77%、45%;2年局部控制率为81%;1年无局部进展率为88%;1年局部复发率为15%。碳离子和质子治疗PaC的2、3、2~3级胃肠道溃疡发生率分别为6.8%、1.5%、9.2%和3.5%、8.3%、6.1%(均P>0.05);1、2年OS分别为77.1%、44.4%和77.6%、49.7%(P均>0.05)。结论 碳离子和质子治疗PaC安全有效,两者的安全性和有效性相似。  相似文献   
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Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases.  相似文献   
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Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.  相似文献   
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