真空采血器采血时，首先应采集（ ）。

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='30904' and id < 2486513 and id<>'2486513' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='30904' and id > 2486513 and id<>'2486513' order by id asc limit 5