已知数列{an}的前n项和Sn=an2+bn(a、b∈R),且S25=100,则

题型:选择题

问题:

已知数列{an}的前n项和Sn=an2+bn(a、b∈R),且S25=100,则a12+a14等于(  )

A.16

B.8

C.4

D.不确定

考点:等差数列的定义及性质
题型:选择题

患者男性,70岁。双上肢震颤3年,行走困难1年就诊。既往有前列腺增生病史5年。查体:神清语利,高级智能正常,口唇及双上肢有静止性震颤,四肢肌张力高,四肢腱反射正常存在,四肢病理征阴性。行走呈慌张步态。

关于帕金森病下述描述正确的是()

A.黑质多巴胺能神经元变性缺失

B.乙酰胆碱能神经元变性缺失

C.路易小体形成

D.多巴胺含量降低

E.乙酰胆碱含量降低

F.脑基底节变性

题型:选择题

复合树脂充填时首选基底料

A.氧化锌丁香油水门汀

B.磷酸锌水门汀

C.玻璃离子水门汀

D.牙胶

E.护洞漆

题型:选择题

数据库三级模式体系结构的划分,有利于保持数据库的______。

A.数据独立性

B.数据安全性

C.结构规范化

D.操作可行性

题型:选择题
Several years ago I studied in a university in the biggest city in our country. It’s very beautiful, I could read lots of books there and I made lots of friends there. But it’s hot in  11 . So I usually returned to my hometown when my   12  began. It is not big, but it’s cool and quiet. I could   13  in the daytime and have a good sleep at night.
One day I had some problems to solve. But I didn’t take the   14  home. My father told me Charlie, one of my   15 , had a good library. I went to his house at once. We didn’t see each other after I   16  my middle school. At first he didn’t   17  me. He looked me up and down. And then he called out, “Oh, dear! It’s you, Fred! I haven’t seen you for a long time!”
Of course we were   18  to meet each other again and talked a lot about our schoolmates and   19 . We also talked about the interesting things at that time. Later on he showed me around his   20 . It wasn’t big but there were a lot of nice books in it. And the dictionaries I   21  were in it too. At last I said, “Can you   22  some dictionaries to me, please?”
“I’m sorry I don’t lend any books to others,” said the young man.
“Are you afraid I’ll   23  them?”
“No, I’m not. I’m afraid you won’t   24  them to me. Look! All the books in my library are not   25 , but borrowed!”
小题1:
A.springB.summerC.autumnD.winter
小题2:
A.birthdayB.SaturdayC.SundayD.holiday
小题3:
A.studyB.playC.restD.work
小题4:
A.booksB.notebooksC.dictionariesD.magazines
小题5:
A.brothersB.sistersC.neighborsD.classmates
小题6:
A.finishedB.heard ofC.looked atD.visited
小题7:
A.seeB.hearC.recognizeD.call
小题8:
A.angryB.happyC.worriedD.sad
小题9:
A.doctorsB.teachersC.workersD.drivers
小题10:
A.factoryB.officeC.libraryD.house
小题11:
A.neededB.readC.wroteD.liked
小题12:
A.passB.sendC.giveD.lend
小题13:
A.loseB.sellC.throwD.read
小题14:
A.payB.returnC.sendD.give
小题15:
A.foundB.givenC.wonD.bought
题型:选择题

仙鹤草除止血外,还能:
血余炭除收敛止血外,还能:

A.清热解毒

B.止痢杀虫

C.化瘀利尿

D.固精缩尿

E.涩肠止泻

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