血中Hb含量低于多少时，即使重度缺氧，亦难发现发绀

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SQL Error: select id,body,options from ***_enewstiku where sourceid='28168' and id < 2307027 and id<>'2307027' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='28168' and id > 2307027 and id<>'2307027' order by id asc limit 5