急性感染性多发性神经根炎患儿,双下肢能在床面上活动,可克服地心引力,但不能抵抗阻力,患儿的肌力是()
A.0级
B.1级
C.2级
D.3级
E.4级
参考答案:D
The London 2012 Olympic Games marks the third time that London ______ the right to host the modern Olympics.
A.had had
B.has
C.had
D.has had
灰级窗,是只将灰度值落在一定范围内的目标进行(),就好像开窗观察只落在视野内的目标内容一样。