泌 * * 感染最常见的致病菌是（）
A.绿脓杆菌
B.大肠杆菌
C.克霉伯杆菌
D.肠球菌
E.葡萄球菌
参考答案：B
A．悦耳动听的笛声不是靠管子里的空气振动产生的
B．激光准直打隧道是利用了光的反射
C．利用声传递能量清洗钟表等精密机械内的污垢
D．电影银幕较为粗糙，不是为了增加光的漫反射效果
The nurse is teaching a client recently diagnosed with myasthenia gravis. The nurse should teach the client that myasthenia gravis is caused by
A．genetic dysfunction.
B．upper and lower motor neuron lesions.
C．decreased conduction of impulses in an upper motor neuron lesion.
D．a lower motor neuron lesion.
