Large explosive volcanic eruptions generate extensive regional tephra deposits that provide favorable conditions for identifying the source of volcanoes, comparing the sedimentary strata of a region and determining th...Large explosive volcanic eruptions generate extensive regional tephra deposits that provide favorable conditions for identifying the source of volcanoes, comparing the sedimentary strata of a region and determining their ages. The tephra layer, referred to as B- Tm, generated by the Millennium eruption of Chang- baishan volcano, is widely distributed in Northeast China, Japan, D.P.R. Korea, and the nearby coastal area of Russia. It forms part of the widespread northeast Asian strata and is significant for establishing an isochronal stratigraphic framework. However, research on the temporal characterization and stratigraphic correlation of associated strata using this tephra layer is mainly concentrated in and near Japan. In northeastern China, this tephra layer is seldom seen and its application in stratigraphic correlations is even rarer. More importantly, the determination of accurate ages for both distal and proximal tephras has been debated, leading to controversy in discussions of its environmental impacts. Stratigraphic records from both distal and proximal Changbaishan ash show that this eruption generally occurred between 1,012 and 1,004 cal yr BP. Geochemical comparison between Changbaishan ash and the Quaternary widespread ash around Japan illustrates that Changbaishan ash is a continuous composition from rhyolitic to trachytic and its ratio of FeOT to CaO is usually greater than 4, which can be used as a distinguishing identifier among worldwide contemporary eruptions.展开更多
近年来,在细胞治疗和再生医学领域,自体或异体细胞移植治疗疾病正在成为现实.骨髓间充质干细胞具有分化成多种细胞的潜能,已被广泛用于各种疾病的研究和治疗.活体追踪移植细胞,检测移植细胞的生存及功能状态对于评价移植治疗效果至关重...近年来,在细胞治疗和再生医学领域,自体或异体细胞移植治疗疾病正在成为现实.骨髓间充质干细胞具有分化成多种细胞的潜能,已被广泛用于各种疾病的研究和治疗.活体追踪移植细胞,检测移植细胞的生存及功能状态对于评价移植治疗效果至关重要.目前,利用磁共振对比剂超顺磁性氧化铁颗粒(SPIO),活体追踪和监测标记细胞已被广泛用于动物实验研究和一些临床疾病诊断.但MRI信号不能显示移植细胞在体内的生物学特征.本研究中,对食蟹猴骨髓间充质干细胞体外标记Molday ION rhodamine-B^(TM)(MIRB),探讨MIRB标记后cMSCs的细胞生物学特性,以及脑内移植后的活体MRI影像学及组织学追踪.结果表明,MIRB具有生物组织相容性,能高效标记cMSCs,可用于体内多模式追踪移植细胞,为利用MIRB追踪和检测移植细胞,以及干细胞移植治疗机制的研究提供资料.展开更多
基金Acknowledgements The authors thank the anonymous reviewers and the editor for their helpful reviews and constructive suggestions which greatly improved the original manuscript. We also thank Drs. Z Guo, H He, X Chen and L Zhang for their help during the preparation of this manuscript. This work was supported by the National Natural Science Foundation of China （Grant Nos. 41272369, 40802038, and 41320104006）.
文摘Large explosive volcanic eruptions generate extensive regional tephra deposits that provide favorable conditions for identifying the source of volcanoes, comparing the sedimentary strata of a region and determining their ages. The tephra layer, referred to as B- Tm, generated by the Millennium eruption of Chang- baishan volcano, is widely distributed in Northeast China, Japan, D.P.R. Korea, and the nearby coastal area of Russia. It forms part of the widespread northeast Asian strata and is significant for establishing an isochronal stratigraphic framework. However, research on the temporal characterization and stratigraphic correlation of associated strata using this tephra layer is mainly concentrated in and near Japan. In northeastern China, this tephra layer is seldom seen and its application in stratigraphic correlations is even rarer. More importantly, the determination of accurate ages for both distal and proximal tephras has been debated, leading to controversy in discussions of its environmental impacts. Stratigraphic records from both distal and proximal Changbaishan ash show that this eruption generally occurred between 1,012 and 1,004 cal yr BP. Geochemical comparison between Changbaishan ash and the Quaternary widespread ash around Japan illustrates that Changbaishan ash is a continuous composition from rhyolitic to trachytic and its ratio of FeOT to CaO is usually greater than 4, which can be used as a distinguishing identifier among worldwide contemporary eruptions.
文摘近年来,在细胞治疗和再生医学领域,自体或异体细胞移植治疗疾病正在成为现实.骨髓间充质干细胞具有分化成多种细胞的潜能,已被广泛用于各种疾病的研究和治疗.活体追踪移植细胞,检测移植细胞的生存及功能状态对于评价移植治疗效果至关重要.目前,利用磁共振对比剂超顺磁性氧化铁颗粒(SPIO),活体追踪和监测标记细胞已被广泛用于动物实验研究和一些临床疾病诊断.但MRI信号不能显示移植细胞在体内的生物学特征.本研究中,对食蟹猴骨髓间充质干细胞体外标记Molday ION rhodamine-B^(TM)(MIRB),探讨MIRB标记后cMSCs的细胞生物学特性,以及脑内移植后的活体MRI影像学及组织学追踪.结果表明,MIRB具有生物组织相容性,能高效标记cMSCs,可用于体内多模式追踪移植细胞,为利用MIRB追踪和检测移植细胞,以及干细胞移植治疗机制的研究提供资料.
