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Abnormal accumulation ofα-synuclein contributes to the formation of Lewy bodies in the substantia nigra,which is considered the typical pathological hallmark of Parkinson's disease.Recent research indicates that angiotensin-(1-7)plays a crucial role in several neurodegenerative disorders,including Parkinson's disease,but the underlying mechanisms remain elusive.In this study,we used intraperitoneal administration of rotenone to male Sprague-Dawley rats for 4 weeks to establish a Parkinson's disease model.We investigated whether angiotensin-(1-7)is neuroprotective in this model by continuous administration of angiotensin-(1-7)into the right substantia nigra for 4 weeks.We found that angiotensin-(1-7)infusion relieved characteristic parkinsonian behaviors and reducedα-synuclein aggregation in the substantia nigra.Primary dopaminergic neurons were extracted from newborn Sprague-Dawley rat substantia nigras and treated with rotenone,angiotensin-(1-7),and/or the Mas receptor blocker A-779 for 24 hours.After binding to the Mas receptor,angiotensin-(1-7)attenuated apoptosis andα-synuclein aggregation in rotenone-treated cells.Primary dopaminergic neurons were also treated with angiotensin-(1-7)and/or the autophagy inhibitor 3-methyladenine for 24 hours.Angiotensin-(1-7)increasedα-synuclein removal and increased the autophagy of rotenone-treated cells.We conclude that angiotensin-(1-7)reducesα-synuclein aggregation by alleviating autophagy dysfunction in Parkinson's disease.Therefore,the angiotensin-(1-7)/Mas receptor axis plays an important role in the pathogenesis of Parkinson's disease and angiotensin-(1-7)has potential therapeutic value for Parkinson's disease.All experiments were approved by the Biological Research Ethics Committee of Nanjing First Hospital(approval No.DWSY-2000932)in January 2020.  相似文献   
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目的探讨经单根冠状动脉和冠状静脉窦(CS)顺行性/逆行性同时心肌灌注(SARC)的效果。方法将离体猪心分别经左前降支(LAD)、左回旋支(LCX)或右冠状动脉(RCA)中的1支和CS行SARC,再依次向动、静脉灌注通路内注入磁共振造影剂[钆喷替酸葡甲胺(Gd-DTPA)]。应用磁共振成像(MRI)检测心肌内造影剂的分布以及对非灌注冠状动脉回流液进行分析,评估心肌灌注效果。结果SARC期间经单根冠状动脉注入Gd-DTPA不但使其支配区域磁共振信号增强,而且其余2根非灌注冠状动脉的支配区域信号也增强(包括右心室游离壁);而SARC期间经CS注入Gd-DTPA只引起非灌注冠状动脉支配区变亮,灌注冠状动脉的支配区和右心室游离壁的信号强度无改变。SARC期间非灌注冠状动脉收集的回流液速度分别为:LAD 10.5~17.7ml/min,LCX 9.7~15.2ml/min,RCA 4.7~7.8ml/min。结论经单根冠状动脉和CS同时灌注可以提供全面均匀的心肌灌注,足以防止非灌注冠状动脉支配区发生心肌缺血损伤。  相似文献   
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通过对小鼠注射过量的甲状腺素使之成为甲亢模型。采用特异结合蛋白的饱和分析法测定小鼠体内各组织器官中CAMP的含量。结果表明甲亢型小鼠各组织器官中的CAMP水平上升,与对照组比较均有显著性差异。由此证明甲状腺素具有增加生物组织器官中CAMP的作用。  相似文献   
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Comparative studies are made on the relative percentages of amino acid content and LDH isozyme by electrophoresis and Slab-PAGE in adult worms of Ascaris lumbricoides, Ascaris suum and Toxocara canis. The results show that there are remarkable differences of Arg and His of 17 amino acids bet. ween Toxocara canis and human intestinal ascaris, human biliary ascaris and pig ascaris; there are also obvious differences of band positions of LDH isozyme electrophoretic patterns and band position and amount of slab-PAGE patterns among them, whereas no marked differences are found in these three indices in human intestinal ascaris, human biliary ascaris and pig ascaris.  相似文献   
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The authentic sequence of rotavirus SA11 nonstructural protein NSP4   总被引:2,自引:0,他引:2  
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Normal intraocular pressure (IOP) glaucoma is a clinical condition characterized by pathologic optic nerve excavation and visual field impairment, defined as optic neuropathy with certain features of a disease known as glaucoma. Glaucomatous optic nerve lesion is characterized by optic disk excavation or depression, however, this feature may greatly vary. The level of IOP is considered only one of the multiple risk factors involved in the disease development. In normal IOP glaucoma, papillary lesions and visual field impairments may differ from those occurring in primary open-angle glaucoma. In modern ophthalmology, the terminology has been modified, so the term low IOP glaucoma has been replaced by the term normal IOP glaucoma. It is now believed that various factors play a role in the development of glaucomatous optic neuropathy in normal IOP glaucoma and show variable interference depending on IOP level. Additional studies are needed to define these interactions and their impact on the mechanism of glaucomatous excavation. This will hopefully pave the way to new therapeutic approaches and help in clinical decisions concerning the prognosis and treatment of individual patients.  相似文献   
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The upper lid position is abnormal if it exposes a white band of sclera between the lid margin and the upper corneal limbus while the retracted lower lid lies below the inferior corneal margin and is tethered to the orbital margin. Lid retraction is a sign of many congenital and acquired diseases and is characterised by multifactorial etiology. The aim of this study was to discuss the etiology of lid retraction divided into four categories: neurogenic, myogenic, mechanical and miscellaneous, what suggests a successful differential diagnostic and therapeutic approach.  相似文献   
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