( )既可以分离蛋白质，又可以测定相对分子质量。

试卷相关题目

SQL Error: select id,body,options from ***_enewstiku where sourceid='29807' and id < 2419221 and id<>'2419221' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29807' and id > 2419221 and id<>'2419221' order by id asc limit 5