韧皮部中的物质可以双向运输。（   ）

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='2629' and id < 197520 and id<>'197520' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='2629' and id > 197520 and id<>'197520' order by id asc limit 5