尿素是第一个人工合成的有机物，下列关于尿素的叙述不正确的是  

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='21779' and id < 1897114 and id<>'1897114' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='21779' and id > 1897114 and id<>'1897114' order by id asc limit 5