先导通道的形成是以（）的出现为特征。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='32664' and id < 2597750 and id<>'2597750' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='32664' and id > 2597750 and id<>'2597750' order by id asc limit 5