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Viral Hepatitis B: Seroprevalence and Genetic Diversity in Blood Donors North of Congo 被引量:1
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作者 Arnaud Mongo-Onkouo Amelia Dzia Lepfoundzou +9 位作者 Dinghat Ornela Marlyne Yvonne Ahoui Apendi Clausina Philestine Jile Florent Mimiesse Monamou Ngala Akoa Itoua-Ngaporo Rody Stéphane Ngami Mouakosso Marlyse Ngalessami Céline Sandra Adoua Deby Gassaye Blaise Irénée Atipo Ibara Jean-Rosaire Ibara 《Open Journal of Gastroenterology》 2019年第12期239-245,共7页
Introduction: Viral hepatitis B is the most formidable and confusing of all viral hepatitis, given its cirrhogenic and carcinogenic potential. The objective of the study is to characterize the molecular profile of hep... Introduction: Viral hepatitis B is the most formidable and confusing of all viral hepatitis, given its cirrhogenic and carcinogenic potential. The objective of the study is to characterize the molecular profile of hepatitis virus B in northern Congo. Materials and Methods: This was a descriptive and cross-sectional study that was carried out between January and September 2014, that is 9 months, in the establishments of the National Center for Blood Transfusion (CNTS) of the 4 departments of the north of the Congo. Epidemiological, serological and molecular variables (HBsAg, HBV DNA, genotypes and subtypes) were studied. The HBs antigen was searched by rapid test and confirmed by ELISA. For all positive donors, conventional and specific gene extraction and amplification techniques were performed for the identification of genotypes and subtypes from the serum. Results: A total of 892 donors were included. The average age was 35.36 ± 12.36 years with extremes ranging from 18 to 65 years old. The sex ratio (M/F) was 3.3. The prevalence of HBV was 8.6%. The viral DNA of HBV was amplified in 83.1%. Four genotypes were found: E (40.6%), A (3.1%), B (3.1%) and C (1.6%). Two cases of co-infection were identified: E/A (15.6%) and B/C (1.6%). Subgenotypes A1, B2 and C1 were highlighted. Conclusion: The prevalence of HBV is high, HBV infection remains a major public health problem for blood donors in Congo. Genotypes E, A, B, C as well as subtypes A1, B2, C1 have been identified in northern Congo. 展开更多
关键词 HBV Molecular BIODIVERSITY Subgenotypes north congo
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华北克拉通和巴西圣弗朗西斯科-刚果克拉通新元古代早期岩浆作用(ca.940~890Ma)序列与成因
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作者 苏向东 彭澎 《岩石学报》 SCIE EI CAS 北大核心 2025年第1期167-182,共16页
华北克拉通和巴西圣弗朗西斯科-刚果克拉通新元古代早期的岩墙和岩床及玄武岩(ca.940~890Ma)岩浆活动时间对比和古地磁研究结果表明,上述克拉通在新元古代可能相邻。这些阶段性岩浆作用的演化趋势和源区特征及其所反映的地质过程与构造... 华北克拉通和巴西圣弗朗西斯科-刚果克拉通新元古代早期的岩墙和岩床及玄武岩(ca.940~890Ma)岩浆活动时间对比和古地磁研究结果表明,上述克拉通在新元古代可能相邻。这些阶段性岩浆作用的演化趋势和源区特征及其所反映的地质过程与构造背景对进一步开展大陆重建有重要意义。本文系统总结和对比分析了两个克拉通新元古代镁铁质岩石的岩相学、地球化学和同位素年代学数据。研究发现,这些岩石大致可分为两类多期:(1)年龄较老(ca.940~920Ma)且演化的高Ti岩石(MgO<6.5%,TiO_(2)>2%),负Eu异常明显(Eu/Eu^(*)=0.7~1.0);(2)年龄较年轻(ca.915~890Ma)且较为原始的低Ti岩石(MgO>6.5%,TiO_(2)<2%),具有正Eu异常(Eu/Eu^(*)=1~1.2)或者没有Eu异常(Eu/Eu=1)。早期高Ti岩浆源区类似于EMⅠ型地幔端元(ε_(Nd)(t)=-8~+3),Sr-Nd同位素特征表明其可能是软流圈上涌熔融产生的岩浆与岩石圈地幔相互作用的结果;而晚期低Ti岩石Nd同位素与球粒陨石值类似(ε_(Nd)(t)=-2~+3),可能来源于软流圈地幔。这两类岩石在华北克拉通和巴西圣弗朗西斯科-刚果克拉通几乎同时出现,且可类比。岩浆演化趋势、微量元素和Sr-Nd同位素等特征及单斜辉石-熔体平衡深度计算表明,早期高Ti岩浆产生于大陆岩石圈破裂初期,经历了较高程度的结晶分异作用;而晚期低Ti岩浆的持续作用(~30Myr)可能与岩石圈破裂过程中不断增强的软流圈岩浆活动相关。该裂谷演化进程在Sr同位素特征变化上也有体现,即与早期高Ti岩石相比,晚期低Ti岩石的Sr同位素更为富集但Nd同位素保持不变,表明该类岩石的产生可能在大陆裂谷发育过程中受到海水蚀变的影响。以上证据表明,华北克拉通和巴西圣弗朗西斯科-刚果克拉通在新元古代早期具有可类比的岩石圈应力演化状态,且经历了相似的地幔地球化学动力学过程,支持两个克拉通在该时期相邻。 展开更多
关键词 华北克拉通 圣弗朗西斯科-刚果克拉通 新元古代 大火成岩省
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