制约课程的三大因素是________、________和________。
参考答案:知识;社会;儿童
It's a nice day. Let's go out and walk the dog, _____?
A. shall we
B. will you
C. don't we
D. do you
关于抑制磁化率伪影的对策中,错误的是()
A.做好匀场,磁场越均匀,磁化率伪影越轻
B.增加矩阵
C.减少磁化率差
D.增加TE
E.去除受检者体内或体表的金属异物