由2分子异戊二烯构成的成分是

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30288' and id < 2449079 and id<>'2449079' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30288' and id > 2449079 and id<>'2449079' order by id asc limit 5