阿司匹林引起胃黏膜出血的原因除外()
A.直接刺激胃黏膜
B.促进胃黏膜局部PG生物转化
C.抑制血小板聚集
D.抑制凝血酶原的形成
E.刺激胃酸的分泌
参考答案:B
西北干旱、半干旱区东西差异的主要成因是 ( )
A.热量条件
B.干湿程度
C.地貌类型
D.植被类型
In Copenhagen,the UN climate conference grew more tense and divisive asthe developing countries
didn't trust the promises made by the industrial countries to_____ greenhouse gas emission (排放) . [ ]
A. cut out
B. cut down
C. cut off
D. cut up