( )是生殖细胞的最初发源地，又是人胚最早的造血场所。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='31090' and id < 2499984 and id<>'2499984' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='31090' and id > 2499984 and id<>'2499984' order by id asc limit 5