链霉素的主要不良反应是（）
A.耳毒性
B.肾毒性
C.再生障碍性贫血
D.二重感染
E.耐药
参考答案：B
36. People are deeply struck by Forrest Gump because of his unselfish _______ to helping others.
A．devotion
B．invitation
C．expression
D．Protection
液压支架的初撑力由哪些因素决定？
