如果模式只是BCNF,则R必是( ):反之,则( )成立。
参考答案:3NF 不一定
Some people try to knock me down, only______ me more determined to do better. [ ]
A. to make
B. makes
C. having made
D. made
男性患者,42岁。不规则低热3个月,厌食,体重下降5kg,右季肋下胀痛,巩膜轻度黄染,面部有3个蜘蛛痣,肝肋下3.5cm,质硬表面不平,脾肋下1cm,肝区可闻及血管杂音,血白细胞5.8×109/L,中性粒细胞0.64,谷丙转氨酶130U/L,碱性磷酸酶30U/L。经中西医治疗无效。应首先考虑的诊断是()
A.慢性活动性肝炎
B.原发性肝癌
C.门脉性肝硬化
D.肝脓肿
E.肝血管瘤