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91.
目的研究吸入性麻醉药七氟烷对发育期神经元的凋亡作用,并探究七氟烷对原代神经元线粒体功能的影响。方法体外培养原代神经元,并随机分为对照组和实验组,实验组用4.1%七氟烷处理6 h,western blot检测Cleaved caspase-3凋亡蛋白的变化,流式细胞术检测神经元的凋亡率,DCFH-DA法检测细胞中ROS含量的变化,并检测ATP水平的变化。结果与对照组相比,七氟烷组的凋亡蛋白Cleaved caspase-3上调(P<0.01),凋亡率增加(P<0.05),ROS生成增加(P<0.05)同时ATP生成减少(P<0.05)。结论七氟烷可以诱导原代神经元的凋亡,其作用机制可能是通过线粒体能量代谢和氧化应激水平改变引起。 相似文献
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Saúl Reveles‐Flix Rosalba Carren‐Npoles Susana Mendoza‐Elvira Víctor Quintero‐Ramírez Juvencio García‐Snchez Rebeca Martínez‐Bautista Manuel Saavedra‐Montaez Juan Joel Mosqueda Gualito Jos Ivan Snchez‐Betancourt 《Transboundary and Emerging Diseases》2020,67(2):1035-1041
As an emerging disease, the porcine epidemic diarrhoea virus has caused substantial economic losses to the pork industry in Mexico, leading to piglet mortality rates of up to 100%. For detection, sequencing and genetic characterization of the virus, 68 samples of one‐week‐old piglets from pork farms in 17 states of Mexico were analysed. In total, 53 samples were positive by real‐time RT‐PCR, confirming the presence of the virus in 15 states. Twenty‐eight samples from 10 states were amplified by endpoint RT‐PCR, and 20 sequences of the spike gene were obtained. A phylogenetic analysis based on the spike gene demonstrated that all Mexican strains are in Group II and are classified as non‐Indel‐S emerging variants. Three strains showed amino acid insertions: PEDv/MEX/GTO/LI‐DMZC15/2015 and PEDv/MEX/QRO/LI‐DMZC45/2016 showed one amino acid insertion (424Y425 and 447D448, respectively), and PEDv/MEX/QRO/LI‐DMZC49/2019 showed one and two amino acid insertions (422C423 and 537SQ538), with the second insertion in the COE region. These results provide evidence of the prevalence of emerging, non‐Indel‐S strains of the virus are currently circulating in Mexico during 2016–2018, when three of which have amino acid insertions: PEDv/MEX/GTO/IN‐DMZC15/2015 and PEDv/MEX/QRO/IN‐DMZC45/2016 have one amino acid insertion each (424Y425 and 447D448, respectively), and PEDv/MEX/QRO/IN‐DMZC49/2019 has one (422C423) and two amino acid insertions (537SQ538), the latter being in the COE region, which could generate new antigenic variants. 相似文献
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Appropriate hypothermic packaging techniques are an essential part of organ procurement. We present a case in which deviation from standard packaging practice may have caused sub‐zero storage temperatures during transport, resulting in a clinical picture resembling PNF. An 18‐month‐old male with alpha‐1‐antitrypsin deficiency underwent liver transplant from a size‐matched pediatric donor. Upon arrival at the recipient hospital, ice crystals were noted in the UW solution. The transplant proceeded uneventfully with short ischemia times. Surprisingly, transaminases, INR, and total bilirubin were markedly elevated in the postoperative period but returned to near normal by discharge. Follow‐up of over five yr has demonstrated normal liver function. Upon review, it was discovered that organ packaging during recovery included storage in the first bag with only 400 mL of UW solution, and pure ice in the second bag instead of slush. This suggests that the postoperative delayed graft function was related to sub‐zero storage of the graft during transport. This is the first report of sub‐zero cold injury, or frostbite, following inappropriate packaging of an otherwise healthy donor liver. The clinical picture closely resembled PNF, perhaps implicating this mechanism in other unexpected cases of graft non‐function. 相似文献
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电磁波目前广泛应用于无线通信、军事、医疗等领域,与此同时,电磁辐射的生物效应和对健康的影响也愈来愈受人们的重视。电磁辐射可引起机体多系统、多脏器的损伤,本文就电磁辐射的损伤机制及其对大脑、心脏、眼睛和血液等重要器官系统影响的研究进展作一综述。 相似文献