导体和电器的发热，主要由（  ）等多种因素引起。 

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69482' and id < 4500377 and id<>'4500377' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69482' and id > 4500377 and id<>'4500377' order by id asc limit 5