呆小症的病因主要是缺少（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='27771' and id < 2283358 and id<>'2283358' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='27771' and id > 2283358 and id<>'2283358' order by id asc limit 5