低钾血症的病人，补钾后病情仍无改善时，应首先考虑缺乏（）
A.镁
B.磷
C.钠
D.氯
E.钙
参考答案：A
It is not rare in ________ that people in ________ fifties are going to university for further education.[ ]
A. 90s; the
B. the 90s; /
C. 90s; their
D. the 90s; their
确定缺铁性贫血，下列哪项检查意义最大（）
A.血清铁减低
B.血清总铁结合力增高
C.骨髓细胞外铁缺乏
D.骨髓铁粒幼红细胞减少
E.转铁蛋白饱和度减低
