受精卵着床必须具备的条件是

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SQL Error: select id,body,options from ***_enewstiku where sourceid='31465' and id < 2521372 and id<>'2521372' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='31465' and id > 2521372 and id<>'2521372' order by id asc limit 5