输卵管妊娠需与哪些疾病鉴别A．黄体囊肿破裂 B．急性阑尾炎 C．早期流产 D．盆腔炎

An agreement was made in June when both sides met for the first time in 21 years, ______ by another meeting for further cooperation.

A．following

B．to follow

C．having followed

D．followed

以下接近50g的物体可能是[ ]

A．一粒细砂子　　

B．一只鸡蛋 　　

C．一头大象　　

D．一只母鸡

久泻或佝偻病的患儿脱水及酸中毒纠正后出现惊厥，多考虑为

A．低钾血症
B．低血糖症
C．低钙血症
D．低氯血症
E．低镁血症

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