顺式己烯雌酚没有雌激素活性的原因是（  ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='24971' and id < 2127410 and id<>'2127410' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='24971' and id > 2127410 and id<>'2127410' order by id asc limit 5