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2019年12月以来,湖北省武汉市部分医院陆续发现了多例不明原因肺炎病例,现已证实为新型冠状病毒肺炎(Coronavirus disease 2019,COVID-19)。全国各地采取了前所未有的措施,大力开展疾病救治和防疫工作。本文收集中国国家卫生健康委员会公布的官方统计数据预测疫情走向。传统SEIR模型中仅考虑病例和处于潜伏期的感染者,病例具有传染性而潜伏者无传染性;事实上,新冠肺炎确诊患者在医院中隔离无法对外界易感人群造成感染,有研究表明处于潜伏期的感染者可能具有传染性。因此,本研究提出了改进的传染病传播模型—ISEIR,将患者分为未收治的发病患者(具有传染性)和已收治的确诊患者(不考虑传染性),并考虑处于潜伏期的感染者具有传染性;以历史数据动态拟合模型参数,来摆脱固定参数的局限性。在数据预处理中根据每日有效再生数的概率分布将2020年2月12至14日这三天的临床诊断数据进行预处理,摊入到前期数据中。疫情分成全国(湖北省外)和湖北省两大区域分别进行探讨,通过新模型ISEIR预测今后疫情的进一步发展,并计算每日的有效再生数变化。结果显示,湖北省的有效再生数从3.108逐渐降低,20... 相似文献
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新型冠状病毒肺炎(Coronavirus Disease 2019,COVID 19)是指2019新型冠状病毒(Severe Acute Respiratory Syndrome Coronavirus 2,SARS CoV 2)感染导致的肺炎。截至2020年5月21日已造成全球超过496万人感染、30万人以上死亡。宏基因组下一代测序(metagenomic next generation sequencing,mNGS)技术是在发现和检测新冠肺炎中发挥重要作用的技术。本文介绍了mNGS在新冠肺炎疫情中的作用及核心技术特点,并为mNGS在抗击全球疫情中的应用做出技术性归纳总结。 相似文献
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针对新型冠状病毒肆虐以及暂无特效药物治疗的情况,多地已开展间充质干细胞(MSCs)在新型冠状病毒感染重症救治方面的临床研究,在规范应用的前提下,经过严格的临床检验后,对若干重型患者进行治疗并取得了一定效果。MSCs能抑制免疫系统过度激活,通过改善微环境促进内源性修复、抑制肺部炎症的进展达到缓解呼吸窘迫症状的目的。本文就新型冠状病毒免疫损伤的发生机制、治疗现状以及MSCs在治疗新型冠状病毒感染的潜在治疗机制作一介绍。 相似文献
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2019年末在武汉出现新型冠状病毒肺炎(Coronavirus disease 2019,COVID-19)患者,此后两个月疫情进入暴发期。为了科学有效地对疫情发展趋势进行预判,本研究根据国家及各地方卫生健康委员会公布的官方数据建立了COVID-19确诊、死亡及治愈病例的Logistic分段模型。模型预计全国累计确诊病例将达到81 370～102 800人,累计死亡病例将达到3 177～3 960人,最终病死率约为3.9%。在现有的医疗条件和诊断标准下,预计到2020年5月上旬,全国确诊病例(除死亡外)将全部治愈出院。此模型能较好地拟合和预测COVID-19疫情的不同传播阶段和发展趋势,将为疫情防控提供科学依据。 相似文献
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新型冠状病毒肺炎目前已进入全球大流行状态,多个国家出现疫情爆发。美国疾病管制局期刊《新兴传染病》发表的关于新型冠状病毒的最新研究结论显示,新型冠状病毒基本传染数R0的中位数高达5.7,这意味着在未来较长时间内新型冠状病毒可能会在人群中持续传播并发生变异。在这一背景下,如何监视病毒的变异,对于冠状病毒的研究和药物研发具有重要意义。本文基于来自GISAID的病毒基因组序列数据,设计和实现了新型冠状病毒变异时空分析系统。该系统可对来自不同国家和地区的新型冠状病毒序列数进行统计,对病毒序列在不同时间、不同空间内的变异情况进行分析和可视化,同时还支持不同序列之间的差异比对。该系统可为新型冠状病毒肺炎的研究和政府的疾病控制机构的决策提供支持。 相似文献
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Jiamnin Liu Fan Lu Yinghua Chen Edward Plow Jun Qin 《The Journal of biological chemistry》2022,298(3)
Coronavirus disease 2019 (COVID-19) is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It is broadly accepted that SARS-CoV-2 utilizes its spike protein to recognize the extracellular domain of angiotensin-converting enzyme 2 (ACE2) to enter cells for viral infection. However, other mechanisms of SARS-CoV-2 cell entry may occur. We show quantitatively that the SARS-CoV-2 spike protein also binds to the extracellular domain of broadly expressed integrin α5β1 with an affinity comparable to that of SARS-CoV-2 binding to ACE2. More importantly, we provide direct evidence that such binding promotes the internalization of SARS-CoV-2 into non-ACE2 cells in a manner critically dependent upon the activation of the integrin. Our data demonstrate an alternative pathway for the cell entry of SARS-CoV-2, suggesting that upon initial ACE2-mediated invasion of the virus in the respiratory system, which is known to trigger an immune response and secretion of cytokines to activate integrin, the integrin-mediated cell invasion of SARS-CoV-2 into the respiratory system and other organs becomes effective, thereby promoting further infection and progression of COVID-19. 相似文献
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May A. Alsayb Ali Dakhilallah D. Alsamiri Hatem Q. Makhdoom Turki Alwasaidi Haitham Mohammed Osman Waleed H. Mahallawi 《Saudi Journal of Biological Sciences》2021,28(7):4010-4015
By the beginning of 2021, the battle against coronavirus disease 2019 (COVID-19) remains ongoing. Investigating the adaptive immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, in patients who have recovered from this disease could contribute to our understanding of the natural host immune response. We enrolled 38 participants in this study. 7 healthy participants and 31 COVID-19 patients who had recovered from COVID-19 and categorized them into 3 groups according to their previous clinical presentations: 10 moderate, 9 mild, and 12 asymptomatic. Flow cytometry analysis of peripheral lymphocyte counts in recovered patients showed significantly increased levels of CD4+ T cells in patients with a history of mild and moderate COVID-19 symptoms compared with those healthy individuals (p < 0.05 and p < 0.0001 respectively). whereas no significant difference was observed in the CD8+ T cell percentage in COVID-19-recovered patients compared with healthy individuals. Our study demonstrated that antibodies against the SARS-CoV-2 spike protein (anti-S) IgG antibody production could be observed in all recovered COVID-19 patients, regardless of whether they were asymptomatic (p < 0.05)or presented with mild (p < 0.0001) or moderate symptoms (p < 0.01). Anti-S IgG antibodies could be detected in participants up to 90 days post-infection. In conclusion, the lymphocyte levels in recovered patients were associated with the clinical presentation of the disease, and further analysis is required to investigate relationships between different clinical presentations and lymphocyte activation and function. 相似文献
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BackgroundWe examined the number of lung cancers diagnosed, the quality of care and the socio-economic and clinical characteristics among patients with lung cancer during the COVID-19 pandemic compared to previous years.MethodsWe included all patients ≥ 18 years old diagnosed with lung cancer from 01 January 2018 to 31 August 2021 as registered in the Danish Lung Cancer Registry. Using a generalised linear model, we estimated prevalence ratios (PR) and 95% confidence intervals (CI) of the associations between the pandemic and socioeconomic and clinical factors, and indicators of quality.ResultsWe included 18,113 patients with lung cancer (82.0% non-small cell lung cancer (NSCLC)), which was similar to the preceding years, although a decline in NSCLC cases occurred during the first lockdown period in 2020. No difference in distribution of income or educational level was observed. No difference was observed in the quality of treatment – as measured by curative intent, proportion of patients resected or who died within 90 days of diagnosis.ConclusionUsing nationwide population-based data, our study reassuringly shows no adverse effects of the COVID-19 pandemic on the diagnosis, socio-economic characteristics nor quality of treatment of lung cancer, as compared to the preceding years. 相似文献
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2020年春天,全球进入对抗新型冠状病毒(Severe Acute Respiratory Syndrome Coronavirus 2,SARS-CoV-2)感染引起的\"新冠\"肺炎(Coronavirus Disease,COVID-19)疫情的斗争中。为了适应全民抗\"疫\"的新形势,引导学生理性地、科学地认识此次病毒疫情,\"病毒生物学\"课程的教学从内容到形式也进行了同步设计与微调。除了将教学模式由线下教学变成线上直播,本课程结合疫情发展情况在学期初进行COVID-19的专题讲座,以及通过\"COVID-19-5 min\"形式每次上课进行疫情周报解读,分析国内外疫情并传授病毒流行病学相关知识。另外,对\"病毒生物学\"的教学计划和教学内容做了适当微调,更多关注病毒性传染疾病发展和相关科学研究的进展。通过对在线教学从教学模式、教学过程和教学内容的设计和调整,强化教学效果的反馈和改善,引导学生不信谣、不传谣,帮助学生加强对新型冠状病毒(SARS-CoV-2)及疫情的科学认识。通过教学内容和教学形式的调整以及病毒疫情相关知识点的强化,激发了生物学专业学生对病毒学、流行病学及公共卫生健康等问题的关注。 相似文献
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DD(35)E motif in catalytic core domain (CCD) of integrase (IN) is extremely involved in retroviral integration step. Here, nine single residue mutants of feline foamy virus (FFV) IN were generated to study their effects on IN activities and on viral replication. As expected, mutations in the highly conserved D107, D164, and E200 residues abolished all IN catalytic activities (3′-end processing, strand transfer, and disintegration) as well as viral infectivity by blocking viral DNA integration into cellular DNA. However, Q165, Y191, and S195 mutants, which are located closely to DDE motif were observed to have diverse levels of enzymatic activities, compared to those of the wild type IN. Their mutant viruses produced by one-cycle transfection showed different infectivity on their natural host cells. Therefore, it is likely that effects of single residue mutation at DDE motif is critical on viral replication depending on the position of the residues. 相似文献
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Revisiting Metchnikoff''s work in light of the COVID-19 pandemic illustrates how much this amazing scientist was a polymath, and one could speculate how much he would have been fascinated and most interested in following the course of the pandemic. Since he coined the word “gerontology”, he would have been intrigued by the high mortality among the elderly, and by the concepts of immunosenescence and inflammaging that characterize the SARS-CoV-2 infection. While Metchnikoff''s work is mainly associated with the discovery of the phagocytes and the birth of cellular innate immunity, he regularly invited his closest collaborators to investigate humoral immunity, and it was in his laboratory that Jules Bordet made his major discovery of the complement system. While Metchnikoff and his team investigated many infectious diseases, he also contributed to studies linked to vaccination, such as those on typhoid fever performed in chimpanzees, illustrating that non-human primates can provide animal models which are potentially helpful for understanding the pathophysiology of the COVID-19 virus. In the present review, we illustrate how much his own work and the investigations of his trainees were pertinent to this new disease. 相似文献
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Muhammed Emin Düz Mustafa Arslan Elif E. Menek Burak Yasin Avci 《Journal of Medical Biochemistry》2023,42(1):138
BackgroundCOVID-19 covers a broad clinical spectrum, threatening global health. Although several studies have investigated various prognostic biochemical and hematological parameters, they generally lack specificity and are insufficient for decision-making. Beyond the neonatal period, NRBCs (nucleated red blood cells) in peripheral blood is rare and often associated with malignant neoplasms, bone marrow diseases, and other severe disorders such as sepsis and hypoxia. Therefore, we investigated if NRBCs can predict mortality in hypoxic ICU (Intensive Care Unit) patients of COVID-19.MethodsSeventy-one unvaccinated RT-PCR confirmed COVID-19 ICU patients was divided into those who survived (n=35, mean age=58) and died (n=36, mean age=75). Venous blood samples were collected in K3 EDTA tubes and analyzed on a Sysmex XN-1000 hematology analyzer with semiconductor laser flow cytometry and nucleic acid fluorescence staining method for NRBC analysis. NRBC numbers and percentages of the patients were compared on the first and seventh days of admission to the ICU. Results are reported as a proportion of NRBCs per 100 WBCs NRBCs/100 WBC (NRBC% and as absolute NRBC count (NRBC #, × 109/L).ResultsNRBC 7th-day count and % values were statistically higher in non-survival ones. The sensitivity for 7th day NRBC value <0.01 (negative) was 86.11%, the specificity was 48.57%, for <0.02; 75.00%, and 77.14%, for <0.03; 61.11%, and 94.60%.ConclusionsIn conclusion, our results indicate that NRBC elevation (>0.01) significantly predicts mortality in ICU hospitalized patients due to COVID-19. Worse, a high mortality rate is expected, especially with NRBC values of >0.03. 相似文献
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自2019年底以来,全球范围内爆发了新型冠状病毒SARS-CoV-2引起的COVID-19大流行。SARS-CoV-2与蝙蝠来源的严重急性呼吸综合征(SARS)样冠状病毒高度同源,且穿山甲等野生动物中也鉴定出了同源性高的SARS样冠状病毒,提示SARS-CoV-2的源头与野生动物有关,野生动物资源利用与保护相关的生物安全问题凸显。在此背景下,本文介绍了常见的人畜共患病毒,提出了人类在利用野生生物资源时如何预防此类病毒的建议和思考。呼吁全社会应高度重视野生动物资源生物安全问题,形成\"动物的健康即人类的健康、坚决不吃野味\"的全民共识。 相似文献
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There are no egalitarians in a pandemic. The scale of the challenge for health systems and public policy means that there is an ineluctable need to prioritize the needs of the many. It is impossible to treat all citizens equally, and a failure to carefully consider the consequences of actions could lead to massive preventable loss of life. In a pandemic there is a strong ethical need to consider how to do most good overall. Utilitarianism is an influential moral theory that states that the right action is the action that is expected to produce the greatest good. It offers clear operationalizable principles. In this paper we provide a summary of how utilitarianism could inform two challenging questions that have been important in the early phase of the pandemic: (a) Triage: which patients should receive access to a ventilator if there is overwhelming demand outstripping supply? (b) Lockdown: how should countries decide when to implement stringent social restrictions, balancing preventing deaths from COVID-19 with causing deaths and reductions in well-being from other causes? Our aim is not to argue that utilitarianism is the only relevant ethical theory, or in favour of a purely utilitarian approach. However, clearly considering which options will do the most good overall will help societies identify and consider the necessary cost of other values. Societies may choose either to embrace or not to embrace the utilitarian course, but with a clear understanding of the values involved and the price they are willing to pay. 相似文献