英语翻译以偶六级的英语水平,翻译这篇文章实在吃力,我涕泗横流的期待.由于原文太过庞大,在这里截取了最重要的几部分,虽然还

英语翻译
以偶六级的英语水平,翻译这篇文章实在吃力,我涕泗横流的期待.由于原文太过庞大,在这里截取了最重要的几部分,虽然还是有点多,但是能翻译多少是多少,有点翻译我就很满足了~讨论那部分太多,即使就说说每段大概意思也行!
一、标题：A live,impaired-fidelity coronavirus vaccine protects in an aged,immunocompromised mouse model of lethal disease
二、摘要：Live,attenuated RNA virus vaccines are efficacious but subject to reversion to virulence.Among RNA viruses,replication fidelity is recognized as a key determinant of virulence and escape from antiviral therapy; increased fidelity is attenuating for some viruses.Coronavirus (CoV) replication fidelity is approximately 20-fold greater than that of other RNA viruses and is mediated by a 3′5′ exonuclease (ExoN) activity that probably functions in RNA proofreading.In this study we demonstrate that engineered inactivation of severe acute respiratory syndrome (SARS)-CoV ExoN activity results in a stable mutator phenotype with profoundly decreased fidelity in vivo and attenuation of pathogenesis in young,aged and immunocompromised mice.The ExoN inactivation genotype and mutator phenotype are stable and do not revert to virulence,even after serial passage or long-term persistent infection in vivo.ExoN inactivation has potential for broad applications in the stable attenuation of CoVs and,perhaps,other RNA viruses.
千万千万不要有道的啊、百度翻译的啊、谷歌的啊等等翻译器的脑残翻译！

标题：一个活生生的,受损的高保真冠状病毒疫苗在保护致死性疾病的老年,免疫功能低下小鼠模型.
摘要:减毒活RNA病毒疫苗是有效的,但须回归毒性.其中RNA病毒,复制的保真度是公认的毒力和逃避抗病毒治疗的关键因素; 提高保真度衰减的一些病毒.冠状病毒（冠状病毒）的复制保真度大约是比其它RNA病毒的20倍更大,并且由3'→5'核酸外切酶（外显子）的活性介导的,在核糖核酸校对大概功能.在这项研究中,我们证明了严重急性呼吸道综合徵（SARS）冠状病毒外显子活动结果在一个稳定的突变表型与工程灭活深刻的年轻,老年人和免疫功能低下小鼠的保真度降低体内和衰减发病机制.外显子基因的失活和突变表型是稳定的,不会恢复到毒力,即使在体内连续传代或长期持续感染.外显子的失活具有潜力的冠状病毒的稳定衰减,也许还有其他的RNA病毒广泛的应用.
【你信不信这是我在google翻译上找到的.】
【我也不信】