青霉素、头孢菌素、万古霉素、杆菌肽与下列哪种抗生素合用时具有协调作用
A．四环素
B．红霉素
C．林可霉素
D．庆大霉素
E．氯霉素
参考答案：D
伸直型肱骨髁上骨折，常见的并发症是
A．脂肪栓塞
B．肱骨下端缺血性坏死
C．血管神经损伤
D．损伤性休克
E．骨折延迟愈合
—What do you think of your math teacher?
—He looks serious, but he can make his classes ________. [ ]
A. boring
B. quiet
C. tiring
D. lively
