女性，67岁，双膝痛多年，行走困难。双膝内翻，屈伸受限。X线片示关节边缘广泛骨赘形成，有数个游离体，内侧关节间隙消失。治疗首选
A. 适当休息，少走路，保护患肢
B. 关节清理术
C. 关节融合术
D. 人工关节置换术
使胰蛋白酶原活化的最主要物质是
A. 盐酸
B. 肠致活酶
C. 胰蛋白酶本身
D. 糜蛋白酶
安静时运动神经末梢的囊泡
A. 不释放ACh
B. 有少数囊泡随机释放
C. 有少数囊泡依次轮流随机释放
D. 每秒钟约有200～300个囊泡释放
What is the author's attitude toward changes brought on by technological innovation
A. He is excited about them.
B. He is disturbed by them.
C. He questions their usefulness.
D. He accepts them as natural.
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