代数式(2x3－3x2y－2xy2)－(x3－2xy2+y3)+(-x3+3x2

关于肺棘球蚴病的诊断依据的各项哪一项不正确（）

A.病人有绦虫病史

B.X线胸片可见肺内有密度均匀、边界清楚的圆形阴影

C.超声显示肺内有囊性病变

D.Casoni试验阳性

E.有牧羊犬接触史

补全对话。

Tom: I heard that it was your grandpa's seventieth birthday yesterday. You went to his home with your mother.

Tim: Yes. To my surprise, I saw great changes in my grandpa's family.

Tom: Really? What happened in your grandpa's family?

Tim:    1   . But now he has become better and better because of giving up smoking.

Tom: Oh? You should feel very happy. What about his house?

Tim:    2   . But now it is used to build a rearing pond.

Tom: How is the' pond?

Tim: The pond is nice and deep.  3      .

Tom : Anything else?

Tim:   4  , but now they were cut down, and they're used for making things.

Tom: What great changes! You should be proud of these changes.

Tim : Yeah.

A. Behind his house there used to be some old trees

B. Many kinds of fish are living in it

C. My grandpa used to feel weak

D. There used to be a pool with nothing in it in front of his house

1.          2.            3.          4.        

年轻恒牙牙根形成在萌出后的（）。

A.8～11月

B.1～1年半

C.1～2年半

D.3～5年

E.5年半～6年

女，4岁，半年来多次发现尿色混如米汤，尿常规镜检红细胞8～10/HP，其父亲有肾结石病史。

进一步确诊，哪项检查更有诊断价值（）

A.静脉肾盂造影

B.中段尿培养、计数和药敏试验

C.肾脏CT

D.逆行造影

E.尿钙/尿肌酐比值及24小时尿钙定量

在有2个出口的同一巷道内，最多只允许两组巷道维护人员相向维修作业，两组之间的距离不小于（）m。

A、5

B、10

C、15

D、20