Located along the southern part of the West Qinling orogenic belt,the Yangshan gold deposit is one of the largest in China.The major gold ores of Yangshan are disseminated in metasedimentary host rocks with minor nati...Located along the southern part of the West Qinling orogenic belt,the Yangshan gold deposit is one of the largest in China.The major gold ores of Yangshan are disseminated in metasedimentary host rocks with minor native gold amounts in stibnite-gold quartz veins.Pyrite and arsenopyrite are the major Au-bearing minerals.Hydrothermal muscovite from gold-bearing quartz veins was dated using the in situ Rb-Sr method to determine the formation age of the Yangshan gold deposit.The Rb-Sr isochron date of the muscovite yielded 210.1±5.6 Ma(MSWD=1.2).This date is near the lower end of the period of the mineralized granitic dykes(210.49-213.10 Ma).Two stages of gold enriching process are recognized in the gold-bearing pyrite:the first is incorporated with the Co,Cu,As,Ni enrichment;and the second is accompanied by Bi,Co,Ni,Pb,Cu,Sb concentration.The in-situ sulfur isotopic values of pyrites show a restrictedΔ34s range of-1.43‰to 2.86‰with a mean value of 0.43‰.Trace-element mapping and in-situ sulfur isotopic analysis of pyrite suggest that the sulfur deposits are likely derived from a magmatic source and likely assimilated by sulfur from the sedimentary bedrock.Thus,magmatism plays a critical role in the formation of the Yangshan gold deposit.展开更多
慢性乙型肝炎(chronic hepatitis B,CHB)是全球性的公共卫生问题,我国是CHB危害最为严重的国家之一。母婴传播是乙肝病毒(hepatitis B virus,HBV)感染的重要途径,治疗和阻断孕期HBV传播是降低HBV感染及CHB患病率的重要手段。本文从妊娠...慢性乙型肝炎(chronic hepatitis B,CHB)是全球性的公共卫生问题,我国是CHB危害最为严重的国家之一。母婴传播是乙肝病毒(hepatitis B virus,HBV)感染的重要途径,治疗和阻断孕期HBV传播是降低HBV感染及CHB患病率的重要手段。本文从妊娠期CHB的治疗现状入手,综述了国内外妊娠期CHB抗病毒治疗药物、治疗病毒载量阈值及治疗时机选择,并对妊娠期CHB的治疗新希望提出展望。展开更多
基金financially supported by China Geological Survey Project(Grant No.DD20220971)。
文摘Located along the southern part of the West Qinling orogenic belt,the Yangshan gold deposit is one of the largest in China.The major gold ores of Yangshan are disseminated in metasedimentary host rocks with minor native gold amounts in stibnite-gold quartz veins.Pyrite and arsenopyrite are the major Au-bearing minerals.Hydrothermal muscovite from gold-bearing quartz veins was dated using the in situ Rb-Sr method to determine the formation age of the Yangshan gold deposit.The Rb-Sr isochron date of the muscovite yielded 210.1±5.6 Ma(MSWD=1.2).This date is near the lower end of the period of the mineralized granitic dykes(210.49-213.10 Ma).Two stages of gold enriching process are recognized in the gold-bearing pyrite:the first is incorporated with the Co,Cu,As,Ni enrichment;and the second is accompanied by Bi,Co,Ni,Pb,Cu,Sb concentration.The in-situ sulfur isotopic values of pyrites show a restrictedΔ34s range of-1.43‰to 2.86‰with a mean value of 0.43‰.Trace-element mapping and in-situ sulfur isotopic analysis of pyrite suggest that the sulfur deposits are likely derived from a magmatic source and likely assimilated by sulfur from the sedimentary bedrock.Thus,magmatism plays a critical role in the formation of the Yangshan gold deposit.
文摘慢性乙型肝炎(chronic hepatitis B,CHB)是全球性的公共卫生问题,我国是CHB危害最为严重的国家之一。母婴传播是乙肝病毒(hepatitis B virus,HBV)感染的重要途径,治疗和阻断孕期HBV传播是降低HBV感染及CHB患病率的重要手段。本文从妊娠期CHB的治疗现状入手,综述了国内外妊娠期CHB抗病毒治疗药物、治疗病毒载量阈值及治疗时机选择,并对妊娠期CHB的治疗新希望提出展望。
