甾体化合物依据什么位置取代基的不同将甾体类成分分类

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30242' and id < 2446419 and id<>'2446419' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30242' and id > 2446419 and id<>'2446419' order by id asc limit 5