声像图中，表现为很强回声，其后方留有 声影的是

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SQL Error: select id,body,options from ***_enewstiku where sourceid='31793' and id < 2541748 and id<>'2541748' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='31793' and id > 2541748 and id<>'2541748' order by id asc limit 5