静脉曲张性外痔最常合并的疾病是()
A.直肠息肉
B.肛裂
C.肛 * * 肥大
D.内痔
E.血栓性外痔
参考答案:D
动脑筋,看看下面的对话对不对,对的在括号里打“√”,错的打“×”。
( ) 1. A: Do you have a library?
B: Yes, it is.
( ) 2. A: Welcome to our school!
B: Thank you.
( ) 3. A: Your school is beautiful!
B: Oh, no.
( ) 4. A: I have a new classroom.
B: Really? Let's have a look!
( ) 5. A: Look, that is a canteen.
B: I like chicken.
分辨两种组织间最小密度差异的能力()
A.体素和像素
B.密度分辨率
C.空间分辨率
D.伪影
E.部分容积效应