下肢静脉曲张患者术后早期活动是为了预防（ ）。

试卷相关题目

SQL Error: select id,body,options from ***_enewstiku where sourceid='30909' and id < 2487268 and id<>'2487268' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30909' and id > 2487268 and id<>'2487268' order by id asc limit 5