供应直肠上部的血管起自
A. 肠系膜上动脉
B. 肠系膜下动脉
C. 髂内动脉
D. 髂外动脉
E. 阴部内动脉
第四心音
A. 标志心室收缩的开始
B. 与心房收缩有关
C. 标志心室舒张的开始
D. 似第二心音之回声
E. 似第一心音之回声
F. 下列各心音的临床意义是
Passage OneQuestions 11 to 13 are based on the passage you have just heard.
A. On the second Sunday in May.
B. On the third Sunday in May.
C. On the second Sunday in June.
D. On the third Sunday in June.
The publishing house has brought out an (entire) ______ new edition of the dictionary.
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