修理变压器分接开关时，空气相对湿度不大于75％，开关在空气中曝露时间不得超过（）小时

试述常见抗结核药物的药理作用。

可呈"哑铃"状生长的纵隔肿瘤是（）

A.胸腺瘤

B.气管囊肿

C.心包囊肿

D.神经源肿瘤

E.淋巴瘤

Questions 14-18

·Using the information in the text, complete each sentence 14-8 with an expression from the list below.
·For each sentence (14-18), mark one letter (A -G) on the Answer Sheet.
·Do not mark any letter twice.

• A. different colors
• B. hair follicles
• C. dietary fiber
• D. antioxidant activity
• E. their cholesterol
• F. hair loss
• G. free radicals

A common problem in the elderly is ______.

贫血患者，化验为小细胞正色素性贫血，伴有慢性下肢溃疡，血清铁700μg/L，总铁合力1900μg/L，骨髓外铁（++）。诊断应为（）

A.营养性巨幼细胞贫血

B.缺铁性贫血

C.失血性贫血

D.铁粒幼细胞性贫血

E.慢性感染性贫血

干酪样坏死是一种特殊的

A．液化性坏死

B．湿性坏疽

C．干性坏疽

D．气性坏疽

E．凝固性坏死