只见于RNA而不见于DNA的碱基是

试卷相关题目

SQL Error: select id,body,options from ***_enewstiku where sourceid='30288' and id < 2449034 and id<>'2449034' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30288' and id > 2449034 and id<>'2449034' order by id asc limit 5