封头可分为凸形封头、椭圆形封头和碟形封头。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='24912' and id < 2125296 and id<>'2125296' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='24912' and id > 2125296 and id<>'2125296' order by id asc limit 5