生态农业与乡村经济持续发展

生态农业与乡村经济持续发展张壬午,计文瑛,孙鸿良（天津农业部环境保护研究所,３００１９１）（中国农科院,北京１０００８１）ＥｃｏｌｏｇｉｃａｌＡｇｒｉｃｕｌｔｕｒｅａｎｄＳｕｓｔａｉｎａｂｌｅＤｅｖｅｌｏｐｍｅｎｔｏｆＲｕｒａｌＥｃｏｎｏｍｙ￥．ＺｈａｎｇＲｅｎｗｕ;ＪｉＷｅｎｙｉｎｇ（Ａｇｒｏ－ｅｎｖｉｒｏｎｍｅｎｔＰｒｏｔｅｃｌｉｏｎＩｎｓｔｉｔｕｔｅ,Ｔｉａｎｊｉｎ３００１９１）,ＳｕｎＨｏｎｇｌｉａｎｇ（ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＡｇｒｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｃｓ,Ｂｅｉｊｉｎｇ１０００８１）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（２）：１９—２０．ＴｈｉｓｐａｐｅｒｂｒｉｅｆｌｙｐｒｅｓｅｎｔｓｔｈｅｃｕｒｒｅｎｔｄｅｖｅｌｏｐｍｅｎｔｏｆｅｃｏｌｏｇｉｃａｌａｇｒｉｃｕｌｔｕｒｅｉｎＣｈｉｎａａｎｄｃｏｍｐａｒｅｓｗｉｔｈｔｈｅ＇＇ｓｕｓｔａｉｎａｂｌｅａｇｒｉｃｕｌｔｕｒｅａｎｄｒｕｒａｌｄｅｖｅｌｏｐｍｅｎｔ＇＇（ＳＡＲＤ）ｐｕｔｆｏｒｗａｒｄｂｙＦＡＯ,Ｃｈｉｎａ’ｓｓｕｓｔａｉｎａｂｌｅａ－ｇｒｉｃｕｌｔｕｒｅｉｓｎｏｔｏｎｌｙａｎｉｎｇｅｎｉｏｕｓ     

农业系统生产力（ASP）的量化及其现状分析

农业系统生产力（ＡＳＰ）的量化及其现状分析卢进登,韩纯儒（北京农业大学农学系,１０００９４）ＱｕａｎｔｉｆｉｃａｔｉｏｎｏｆＡｇｒｏｓｙｓｔｅｍＰｒｏｄｕｃｔｉｖｉｔｙ（ＡＳＰ）ａｎｄＡｎａｌｙｓｉｓｏｎｉｔｓＣｕｒｒｅｎｔＳｉｔｕａｔｉｏｎｉｎＣｂｉｎａ￥．ＬｕＪｉｎ－ｄｅｎｇ;ＨａｎＣｈｕｎｒｕ（ＢｅｉｊｉｎｇＡｇｒｉｃｕｌｔｕｒａｌＵｎｉｖｅｒｓｉｔｙｆＢｅｉｊｉｎｇ１０００９４）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（２）：２１－２２．ＢａｓｅｄｏｎａｂｒｉｅｆａｎａｌｙｓｉｓｏｎｔｈｅｆｏｒｍａｔｉｏｎｐｒｏｃｅｓｓｏｆＡＳＰ,ｉｔｓｃｏｎｃｅｐｔｉｓｄｅｓｃｒｉｂｅｄａｎｄａｎｉｎｔｅｇｒａｔｅｄｉｎｄｉ－ｃａｔｏｒｆｏｒｉｔｓｑｕａｎｔｉｆｉｃａｔｉｏｎ—ＡＳＰ２ｉｓｐｕｔｆｏｒｗａｒｄｓ．Ｆｒｏｍｔｈｏｓｅ,ｔｈｅＡＳＰｌｅｖｅｌｓｉｎｖａｒｉｏｕｓｒｅｇｉｏｎｓｏｆＣｈｉｎａａｒｅａｎａｌｙｚｅｄａｎｄ８ｌｅｖｅｌｓａｒｅｄｉｖｉｄｅｄｂｙｕｓｉｎｇ．Ｈｉｅｒａｒｃｈｉｃｃｌｕｓｔｅｒｉｎｇｍｅｔｈｏｄ．Ｉｔ’ｓ：ｃｌａｒｉｆｉｅｄｔｈａｔＡＳ－ＰＩｉｓａｍｏｒｅ     

普通小麦基因组最可能的4个供体的ITS1和ITS2序列及其亲缘关系

对普通小麦（ＴｒｉｔｉｃｕｍａｅｓｔｉｖｕｍＬ．）基因组（ＡＡＢＢＤＤ）最可能的供体－Ｔ．ｕｒａｔｒｔｕＴｈｕｍ．（ＡＡ）、Ｔ．ｍｏｎｏｃｃｕｍｖａｒ．ｂｏｅｏｔｉｃｕｍ（Ｂｏｉｓｓ．）ＭＫ（ＡＡ）、ＡｅｇｉｌｏｐｓｓｐｅｌｔｏｉｄｅｓＴａｕｓｃｈ．和Ａｅ．ｔａｕｓｃｈｉｉ（Ｃｏｓｓ．（ＤＤ）的核糖体ＲＮＡ基因ＩＴＳ区进行了ＰＣＲ扩增和克隆,并测定了ＩＴＳ１和ＩＴＳ２的ＤＮＡ序列,讨论和纠正了前人     

最大概率原理在农田生态系统中的应用

最大概率原理在农田生态系统中的应用姚建民（山西省农科院农业资源综合考察研究所,太原０３０００６）马蓉丽（山西省农科院蔬菜研究所,太原０３０００６）ＡｐｐｌｉｃａｔｉｏｎｏｆＭａｘｉｍｕｍＰｒｏｂａｂｉｌｉｔｙＰｒｉｎｃｉｐｌｅｉｎＦａｒｍｌａｎｄＥｃｏｓｙｓｔｅｍ￥．ＹａｏＪｉａｎｍｉｎ（ＩｎｓｌｉｌｕｔｅｆｏｒＣｏｍ－ｐｒｅｈｅｎｓｉｖｅＳｕｒｖｅｙｏｆＡｇｒｉｃｕｌｔｕｒａｌＲｅｓｏｕｒｃｅｓ,ＳｈａｎｘｉＡｃａｄｅｍｙｏｆＡｇｒｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｅｓ,Ｔａｉｙｕａｎ０３０００６）,ＭａＲｏｎｇｌｉ（ＩｎｓｌｉｔｕｔｅｏｆＶｅｇｅｔａｂｌｅＲｅｓｅａｒｃｇｈ,ＳｈａｎｘｉＡｃａｄｅｍｙｏｆａｇｒｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｅｓ,Ｔａｉｙｕａｎ（０３０００６）．Ｃｈｉｎｅｓｅ,ＪｐｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（４）：５８－６０．Ｉｎｏｒｄｅｒｔｏｓｔｒｅｎｇｔｈｅｎｔｈｅｐｒａｃｔｉｃａｂｉｌｉｔｙｏｆｍａｘｉｍｕｍｐｒｏｂａｂｉｌｉｔｙｐｒｉｎｃｉｐｌｅ,ｔｈｉｓｐａｐｅｒｇｉｖｅｓｏｕｔｓｏｍｅｅｓ－ｓｅｎｔｉａｌｃｏｎｄｉｔｉｏｎｓｎｅｅｄｅｄｆｏｒａｐｐｌｙｉｎｇｔｈ     

辽宁省灾害区划初探

辽宁省灾害区划初探尹功成,梁文举（辽宁省农业区划研究所,沈阳１１００３１）（中国科学院沈阳应用生态研究所,１１００１５）ＡｎＡｐｐｒｏａｃｈｔｏＣａｌａｍｉｔｙＤｉｖｉｓｉｏｎｉｎｇｏｆＬｉａｏｎｉｎｇＰｒｏｖｉｎｃｅ￥．ＹｉｎＧｏｎｇｃｈｅｎｇ（ＬｉａｏｎｉｎｇＩｎｓｌｉｔｕｔｅｏｆＡｇｒｉ－ｃｕｌｔｕｒａｌＤｉｖｉｓｉｏｎｉｎｇ,Ｓｈｅｎｙａｎｇ１１００３１）,ＬｉａｎｇＷｅｎｊｕ（ＩｎｓｌｉｌｕｔｅｏｆＡｐｐｌｉｅｄＥｃｏｌｏｇｙ,ＡｃａｄｅｍｉａＳｉｎｉｃａ,Ｓｈｅｎｙａｎｇ１１００１５）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（４）：６１－６５．ＮａｔｕｒａｌｃａｌａｍｉｔｉｅｓｏｃｃｕｒｗｈｅｎｖａｒｉＯｕｓｎａｔｕｒａｌｐｈｅｎｏｍｎａｅｎｄａｎｇｅｒｌｉｆｅ,ｍｉｎｄｓａｎｄｐｒｏｐｅｒｔｉｅｓ,ｂｕｔｓｏｍｅｐｏｔｅｎｔｉａｌｅｎｖｉｒｏｎｍｅｎｔａｌｄｉｓａｓｔｅｒｓｓｕｃｈａｓｒｎａｎ－ｍａｄｅａｎｄａｎｔｈｒｏｐｏｇｅｎｏｕｓｎａｔｕｒａｌｄｉｓａｓｔｅｒｓｄｅｖｅｌｏｐｓｌｏｗ－ｌｙａｎｄｐｒｏｆｏｕｎｄｌｙ,ｗｈｌｃｈａｒｅｕｎｏｂｖｉｏｕｓａｎｄｎｏｔｒ     

新疆农业绿洲生态建设的探讨

新疆农业绿洲生态建设的探讨夏爱林（新疆农业科学院土壤肥料研究所,乌鲁木齐８３００００）ＡｎＡｐｐｒｏａｃｈｔｏｔｈｅＥｃｏｌｏｇｉｃａｌＣｏｎｓｔｒｕｃｔｉｏｎｏｆＡｇｒｉｃｕｌｔｕｒａｌＯａｓｃｓｉｎＸｉｎｊｉａｎｇ￥ＸｉａＡｉｌｉｎ（ＩｎｓｔｉｔｕｔｅｏｆＳｏｉｌａｎｄＦｅｒｔｉｌｉｚｅｒｓ,ＸｉｎｊｉａｎｇＡｃａｄｅｍｙｏｆＡｇｒｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｅｓ,Ｕｒｏｍｑｉ８３００００）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏ－ｇｙ,１９９３,１２（１）：６７－７０。Ｃｏｍｐａｒｅｄｗｉｔｈｏｔｈｅｒａｒｉｄａｒｅａｓｏｆｔｈｅｗｏｒｌｄ,ｔｈｅａｇｒｉｃｕｌｔｕｒａｌｏａｓｅｓｉｎＸｉｎｊｉａｎｇｐｏｓｓｅｓｓｔｈｅｆｏｌｌｏｗｉｎｇｃｈａｒａｃｔｅｒｓ：１．ｔｈｅｙａｒｅｄｅｓｅｒｔａｎｄｉｒｒｉｇａｔｅｄ,ａｎｄｗａｔｅｒｉｓｔｈｅｍａｉｎｆａｃｔｏｒｆｏｒｔｈｅｉｒｓｕｂｓｉｓｔｅｎｃｅａｎｄｄｅｖｅｌ－ｏｐｒｎｅｎｔ,２．ｔｈｅｒｅａｒｅａｂｕｎｄａｎｔｌｉｇｈｔ,ｈｅａｔａｎｄｗａｔｅｒｒｅｓｏｕｒｃｅｓａｎｄｇｒｅａｔｐｏｔｅｎｔｉａｌｆｏｒｉｎｃｒｅａｓｉｎｇｔｈｅｉｒｐｒｏｄ     

真桑钝绥螨对柑桔全爪螨不同螨态的选择性

真桑钝绥螨对柑桔全爪螨不同螨态的选择性蒲天胜,曾涛,韦德卫（广西农科院植物保护研究所,南宁５３０００７）ＳｅｌｅｃｔｉｖｅＰｒｅｄａｃｉｔｙｏｆＡｍｂｌｙｓｅｉｕｓｍａｋｕｗａｔｏＶａｒｉｏｕｓＭｉｔｅＦｏｒｍｓｏｆＰａｎａｎｙｃｈｕｓｃｉｔｒｉ￥ＰｕＴｉａｎｓｈｅｎｇ;ＺｅｎｇＴａｏ;ＷｅｉＤｅｗｅｉ（ＩｎｓｔｉｔｕｔｅｏｆＰｌａｎｔＰｒｏｌｅｃｔｉｏｎ,ＧｕａｎｇｘｉＡｃａｄｅｍｙｏｆＡｇｒｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｅｓ）．ＣｈｉｎｅｓｅＪｏｕｒ－ｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（１）：３３－３４。ＴｈｅｓｅｌｅｃｔｉｖｅｐｒｅｄａｃｉｔｙｏｆｆｅｍａｌｅａｄｕｌｔｏｆＡ．ｍａｋｕｗａｔｏｃｉｔｒｕｓｍｉｔｅｓｉｓｓｉｍｕｌａｔｅｄｉｎｃｏｍｐａｒｉｓｏｎｗｉｔｈｓｐｅｃｉｅｓｏｆＡｎｉｃｈｏｌｓｉ．Ａ．ｍａｋｕｗａｓｈｏｗｓａｎｅｇａｔｉｖｅｐｒｅｆｅｒｅｎｃｅｔｏｔｈｅａｄｕｌｔｏｆＰ．ｃｉｔｒｉ,ｂｕｔＡ．ｎｉｃｈｏｌｓｉｓｈｏｗｓｎｏｓｅｌｅｃｔｉｖｉｔｙａｎｄｓｗｉｔｃｈｉｎｇ．Ｉｎｍｕｌｔｉ－ｆｏｒｍｃｏｅｘｉｓｔｅｎｔｓｙｓｔｅｍｏｆｍｉｔｅｓ,ｔｈｅｆｕｎｃｔｉｏｎａｌｒｅｓ     

生物固氮─—生态农业的一个重要启动因素

生物固氮─—生态农业的一个重要启动因素陈士平（辽宁省农业科学院土壤肥料研究所,沈阳１１０１６１）ＢｉｏｌｏｇｉｃａｌＮｉｔｒｏｇｅｎＦｉｘａｔｉｏｎ—ＡｎＩｍｐｏｒｔａｎｔＲｕｎｎｉｎｇＦａｃｔｏｒｏｆＥｃｏｌｏｇｉｃａｌＡｇｒｉｃｕｌｔｕｒｅ￥．ＣｈｅｎＳｈｉｐｉｎｇ（ＳｏｉｌａｎｄＦｅｒｔｉｌｉｚｅｒＩｎｓｔｉｌｕｔｅ,ＬｉａｏｎｉｎｇＡｃａｄｅｍｙｏｆＡｇｒｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｅｓ,Ｓｈｅｎｙａｎｇ１１０１６１）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（２）：３１—３３．ＬｅｇｕｍｉｎｏｕｓｇｒｅｅｎｍａｎｕｒｅｃｒｏｐｓｓｕｃｈａｓｓｗｅｅｔｃｌｏｖｅｒａｎｄＡｓｔｒａｇａｌｕｓｈｕａｎｇｈｅｅｎｓｉｓ,ｃａｎｐｒｏｖｉｄｅｄｅｆｉｎｉｔｅａｍｏｕｎｔｏｆｂｉｏｌｏｇｉｃａｌｌｙｆｉｘｅｄ－ＮｔｏｍａｋｅＮ－ｂｕｄｇｅｔｂａｌａｎｃｅ,ｐｒｏｍｏｔｅｓｏｉｌｐｈｙｓｉｃａｌａｎｄｃｈｅｍｉｃａｌｐｒｏｐｅｒ－ｔｉｅｓ,ｒｅｄｕｃｅｓｏｉｌａｎｄｗａｔｅｒｅｒｏｓｉｏｎ,ａｎｄｔｈｕｓ,ｉｎｃｒｅａｓｅｐｅｒｕｎｉｔａｒｅａｙｉｅｌｄａｎｄｔｏｔａｌｏｕｔｐｕｔｗｈｅ     

持续农业是生态农业的继续与发展

持续农业是生态农业的继续与发展袁从,赵强基（江苏省农业科学院,南京２１００１４）ＳｕｓｔａｉｎａｂｌｅＡｇｒｉｃｕｌｔｕｒｅ—ＴｈｅＣｏｎｔｉｎｕａｔｉｏｎａｎｄＤｅｖｅｌｏｐｍｅｎｔｏｆＥｃｏｌｏｇｉｃａｌＡｇｒｉｃｕｌｔｕｒｅ．￥ＹｕａｎＣｏｎｇｙｉ;ＺｈａｏＱｉａｎｇｊｉ（ＪｉａｎｇｓｕＡｃａｄｅｎｚｙｏｆＡｇｒｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｅｓ,Ｎａｎｊｉｎｇ２１００１４）．ＣｈｉｎｅｓｅＪｏｕｍａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（２）：１３－１５．Ｉｎｌｉｇｈｔｏｆｔｈｅｃｏｎｄｉｔｉｏｎｏｆｏｕｒｃｏｕｎｔｒｙ,ｔｈｉｓｐａｐｅｒｉｎｔｒｏｄｕｃｅｓｔｈｅｃｏｎｃｅｐｔｓａｎｄｃｏｎｔｅｎｔｓｏｆｓｕｓｔａｉｎａｂｌｅａ－ｇｒｉｃｕｌｔｕｒｅａｎｄｉｔｓｑｕａｎｔｉｔａｔｉｖｅｅｖａｌｕａｔｉｏｎｉｎｄｉｃｅｓ──ｓｕｓｔａｉｎａｂｉｌｉｔｙ,ｓｔａｂｉｌｉｔｙ,ｅｑｕａｌｉｔｙａｎｄｈａｒｍｏｎｉｔｙ（ｄｉ－ｖｅｒｓｉｔｙ）．Ｓｉｍｐｌｉｆｉｅｄｓｙｓｔｅｍｉｎｐｕｔ—ｏｕｔｐｕｔｅｑｕｉｌｉｂｒｉｕｍｉｓｕｓｅｄｔｏｅｓｔｉｍａｔｅｔｈｅｄｙｎａｍｉｃｓｏｆｓｏｉｌｆｅｒｔｉｌｉｔｙ．Ｐ     

沟稃草属研究札记

本文对沟稃草属Ａｎｉｓｅｂｙｔｒｏｎ Ｍｅｒｒｉｌｌ的系统分类进行了初步的整理与修订。认为Ａｕｌａｃｏｌｅｐｉｓ Ｈａｃｋｅｌ（１９０７）（Ｎｅｏａｕｌａｃｏｌｅｐｉｓ Ｓ．Ｒａｕｓｃｈｅｒｔ（１９８２）ｐｒｏ ｎｏｍ．ｎｏｖ．Ａｕｌａｃｄｅｐｉｓ）ｎｏｎ Ｃ．ｖ．Ｅｉｔｉｎｇｓｈａｕｓｅｎ（１８９３）、Ａｎｉｓｅｌｙｔｒｏｎ Ｍｅｒｒｉｌｌ（１９１０）与Ａｎｉｓａｃｈｎｅ Ｋｅｎｇ（１９５８）是     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细