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问题 单项选择题 A1/A2型题

关于肿瘤发病机制，下列不正确的是（）。

A.肿瘤的发生是一个长期的、分阶段的、多种基因突变积累的过程

B.从遗传角度来说，肿瘤是一种基因病

C.原癌基因的激活或肿瘤抑制基因的失活导致细胞的恶性转化

D.瘤细胞的多克隆性扩增形成肿瘤

E.肿瘤的发生是免疫监视功能丧失的结果

答案

参考答案：D

解析：引起遗传物质DNA损害的各种环境与遗传的致癌因子可能以协同或者序贯的方式，使细胞发生转化。被转化的细胞可先呈多克隆性增生，经过一个漫长的多阶段的演进过程，其中一个克隆可相对无限制地扩增（单克隆性），通过附加突变，选择性地形成具有不同特点的亚克隆，从而获得浸润和转移的能力，形成恶性肿瘤。

填空题



In the early 1970’s, Citibank of New York City became one of the first financial institutions to install ATM’s on a large scale. Since then, the (1) of automated teller machines has increased dramatically. At the time, the bank hoped (2) their operating costs by replacing human tellers with machines. Little did they (3) that the cash machines would become so successful. However, as more banks added (4) automated service through ATM’s, the machines mushroomed all over the world.
To use an ATM, all you need is a (5) issued by your bank. Your bank may also (6) through a credit card, such as MasterCard or Visa. To begin a (7) , you need to insert the card into an ATM and punch in a personal identification number on the (8) . The personal ID number may consist of (9) and can prevent anyone from using the card.
The ATM next flashes instructions on its (10) for carrying out transaction. To get cash, for example, you are instructed to (11) that indicate whether the money should be withdrawn from a checking or a savings account and the (12) . This request is then displayed on the screen. After you press a button to (13) that the information is correct, the ATM goes to (14) .
How safe, you may ask, is banking by ATM The (15) is meant to prevent anyone, no matter who you are, from using a cash card (16) . If you enter the wrong ID number for a card, a message on the screen will (17) . If you fail to produce the correct number for three times, most machines will (18) .As another precaution against (19) , the bank generally limits the amount that may be withdrawn by cash card (20) , say, to $ 200.
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单项选择题

资产配置因年龄而异，（）是典型的青年时期的资产配置。

A.20%现金+80%债券

B.50%股票+40%债券+10%现金

C.40%股票+40%债券+20%现金

D.80%股票+20%现金
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