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【世界决定视界】【视界决定世界】 what you see forms what you'll be 欢迎打开“我与我们的世界”，从此，让我们一起纵览世界之风云变幻、洞察社会之脉搏律动、感受个体之生活命运、挖掘自然之点滴奥妙。 我与我们的世界，既是一个奋斗的世界，也是一个思考的世界。奋而不思则罔，思而不奋则殆。这个世界，你大，它就大；你小，它就小。 欢迎通过上方公众号名称，来挖掘本公众号与大家共享的往期文章，因为，每期都能让你“走近”不一样的世界、带给你不一样的精彩。 推荐将本公众号设为“置顶”或“星标”公众号，以确保第一时间收到最新消息。 本期导读：病毒学(Virology)，是以地球上最微小的非细胞生物病毒为研究对象的一门科学，作为地球生物圈中的一类生物因子，人类对病毒的本质及其生命规律的认识，也已经经历了一个世纪，病毒学获得了巨大的发展。 病毒学现已成为生命科学领域中一门重要的分支学科。病毒学研究的内容涉及病毒的类型、成分、结构、新陈代谢、生长繁殖、遗传、进化、分布等生命活动的各个方面，以及病毒与其他生物和环境的相互关系等。 病毒学研究与生命科学及生物技术密切相关，因为病毒是研究生命活动最简单的模型，为近代研究生物大分子结构及其功能、基因组高效表达与调控提供了有力工具，在人类认识生命现象的过程中提供了许多基本的信息。 同时，病毒一方面能够引起动物、植物及人类各种疾病，如艾滋病，对人类的生存至今仍是巨大的威胁；另一方面，它又可被用来消除害虫、用作外源基因的表达载体，可以为人类所利用。 病毒学涉及医学、兽医、环境、农业及工业等广阔领域，相应发展成噬菌体学、医学病毒学、兽医病毒学、环境病毒学、植物病毒学及昆虫病毒学等分支学科。病毒学已成为人们认识生命本质，发展国民经济和保证人畜健康而必须深入研究的重点学科。 医学病毒学是病毒学的一个重要分支，主要是从医学的角度来研究病毒特性，有时又叫医学分子病毒学。医学病毒学研究范围包括病毒本质，传播模式及致病机制，以及应用层面的药物及疫苗研究。它和分子生物学及药物学关系密切。 病毒是一类比较原始的、有生命特征的、能够自我复制和严格细胞内寄生的非细胞生物。其含义是随着人们对病毒本质认识的不断深入而不断加深，大慨经历过以下几个比较重要的阶段： 1.1892年Ivanofsky因发现烟草花叶病毒(TMV)时，称其为滤过性致病因子 2.1957年Lwoff.A因病毒复制周期的阐明以及一些病毒的细胞培养技术的建立，定义为一类具有严格细胞内寄生和潜在感染性的病原体，并且指出病毒只有一种核酸。 3.1978年luria和Darnell进一步确认了病毒只有一种核酸，能在活细胞复制产生子代病毒粒子。 4.1971年Dienner发现仅有小分子RNA的类病毒(viroid)、1981年在澳大利亚发现类病毒样的拟病毒(virusoid)(卫星病毒)和1982年由Prusiner发现由分子量约50KD构成的阮病毒(virinoorprion)。 同所有的生物一样，病毒是一类具有基因、复制、进化特点，并占据着特殊生态地位的生物实体。在细胞外环境中，以形态成熟的病毒体形式存在，具有一定的大小、形状、密度、沉降系数和化学组成，类似化学大分子；在细胞内环境中，则表现出生物体的基本特征(基因组的复制导致病毒的繁殖，随之出现遗传和变异等一系列典型的生命活动)。 不过，病毒也有其自身特性，包括： 1)不具有细胞结构---所以划分为非细胞生物，其它生物则以细胞作为基本构成单元。 2)病毒体只有一种类型的核酸。 3)特殊的繁殖方式，因绝大多数生物是通过构成机体的各种组分数量有序增加而生长，经过分裂方式完成繁殖。病毒则通过基因组的复制与表达完成新病毒粒子的合成。 4)缺乏完整的酶系统和能量合成系统，生物体的一切代谢活动都需要在酶的作用下进行，同时也需要一定的能量 5)绝对的细胞内寄生，在细胞外不表现出任何生命特征，它的一切生命活动都只有在其生活的寄主细胞内方能进行。这种寄生方式不同于某些微生物如麻风杆菌、立克次氏体、衣原体的寄生，它们主要是源于缺乏外源营养物质或外源的代谢中间体需要寄主提供。 由于病毒是目前已知结构最为简单的生命单位，基于它在细胞外的相对简单性和细胞内的病毒与宿主细胞之间相互作用的复杂性的突出特点，由此成为分子生物学研究复制、信息传递、突变以及其它分子生物学问题的理想对象。 利用分子生物学方法进行研究，其结果不仅促进了病毒学的研究，反过来对分子生物学的发展也起到巨大的推动作用。总之分子病毒学在各个自然科学交叉渗透、互为促进的今天，它的研究和发展无论是在阐明更多的现代生物学的重大课题方面；还是在促进生物技术发展方面都有十分重要的作用。 Coronavirus: How long does it take to recover? 新冠病毒：患上新冠后需要多长时间才能康复？ 小编注：译文部分仅供参考；下面共享的信息，摘自BBC官网2020年05月01日一篇报道；本公众号更多“全球疫情”、 “外媒”、 “国际时事”等相关优质文章，见文末往期精彩；本公众号共享资料下载方式，见文末注释部分。 More than one million people around the world are known to have recovered from coronavirus, according to Johns Hopkins University. But the road back to full health is not the same for everyone. Recovery time will depend on how sick you became in the first place. Some people will shrug off the illness quickly, but for others it could leave lasting problems. Age, gender and other health issues all increase the risk of becoming more seriously ill from Covid-19. The more invasive the treatment you receive, and the longer it is performed, the longer recovery is likely to take. What if I have only mild symptoms? 若只有轻微症状会怎样？ Most people who get Covid-19 will develop only the main symptoms - a cough or fever. But they could experience body aches, fatigue, sore throat and headache. The cough is initially dry, but some people will eventually start coughing up mucus containing dead lung cells killed by the virus. These symptoms are treated with bed rest, plenty of fluids and pain relief such as paracetamol. People with mild symptoms should make a good and speedy recovery. The fever should settle in less than a week, although the cough may linger. A World Health Organization (WHO) analysis of Chinese data says it takes two weeks on average to recover. What if I have more serious symptoms? 若有严重症状会怎样？ The disease can become much more serious for some. This tends to happen about seven to 10 days into the infection. The transformation can be sudden. Breathing becomes difficult and the lungs get inflamed. This is because although the body's immune system is trying to fight back - it's actually overreacting and the body experiences collateral damage. Some people will need to be in hospital for oxygen therapy. GP Sarah Jarvis says: 'The shortness of breath may take some considerable time to improve... the body is getting over scarring and inflammation.' She says it could take two to eight weeks to recover, with tiredness lingering. What if I need intensive care? 若需要特别护理会怎样？ The WHO estimates one person in 20 will need intensive care treatment, which can include being sedated and put on a ventilator. It will take time to recover from any spell in an intensive or critical care unit (ICU), no matter what the illness. Patients are moved to a regular ward before going home. Dr Alison Pittard, Dean of the Faculty of Intensive Care Medicine, says it can take 12 to 18 months to get back to normal after any spell in critical care. Spending a long time in a hospital bed leads to muscle mass loss. Patients will be weak and muscle will take time to build up again. Some people will need physiotherapy to walk again. Because of what the body goes through in ICU, there's also the possibility of delirium and psychological disorders. 'There does seem to be an added element with this disease - viral fatigue is definitely a huge factor,' says Paul Twose, critical care physiotherapist at Cardiff and Vale University Health Board. There have been reports from China and Italy of whole-body weakness, shortness of breath after any level of exertion, persistent coughing and irregular breathing. Plus needing a lot of sleep. 'We do know patients take a considerable period, potentially months, to recover.' But it is hard to generalise. Some people spend relatively short periods in critical care, while others are ventilated for weeks. Will coronavirus affect my healthlong-term? 新冠会影响长期健康不？ We don't know for sure as there is no long-term data, but we can look at other conditions. Acute respiratory distress syndrome (called Ards) develops in patients whose immune systems go into overdrive, causing damage to the lungs. 'There is really good data that, even five years down the line, people can have ongoing physical and psychological difficulties,' says Mr Twose. Dr James Gill, a GP and lecturer at Warwick Medical School, says people also need mental health support to improve recovery. 'You're finding breathing difficult, then the doctor says 'We need to put you on a ventilator. We need to put you to sleep. Do you want to say goodbye to your family?'. 'PTSD [post-traumatic stress disorder] in these most severe patients is not unsurprising. There will be significant psychological scars for many.' There remains the possibility that even some mild cases may leave patients with long-term health problems - such as fatigue. How many people have recovered? 有多少人已经从新冠中康复？ Getting an accurate figure is difficult. As of 1 May, Johns Hopkins University reported more than 1,021,000 people had recovered out of 3.2 million people known to have been infected around the world. A Covid-19 gives prostration of thanks on leaving hospital in Morocco But countries use different recording methods. Some are not publishing recovery figures and many mild infections will be missed. Mathematical models have estimated between 99-99.5% of people recover. Can I catch Covid-19 again? 得过新冠后还会再感染不？ There has been much speculation, but little evidence, on how durable any immunity is. If patients have successfully fought off the virus, they must have built up an immune response. Reports of patients being infected twice may just be down to tests incorrectly recording they were free of the virus. The immunity question is vital for understanding whether people can be reinfected and how effective any vaccine may be. |
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来自： Tomsp360lib > 《COVID-19》
