脊髓灰质炎患者出现肢体肌肉萎缩的原因
A.肌肉失去运动功能所致
B.因肌肉瘫痪使供血减少所致
C.肌肉受到病毒的侵害
D.失去了运动神经的营养作用
参考答案:D
When using the lifeboat compass,you must be careful to().
A.set it on the centerline of the boat
B.apply the correction for compass error
C.keep metal objects away from it
D.All of the above
打击专利垄断的法律武器是强制许可。