相对于非关系模型,关系数据模型的缺点之一就是( )。 A.数据独立性高 B.存取

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问题:

相对于非关系模型,关系数据模型的缺点之一就是( )。

A.数据独立性高
B.存取路径对用户透明,需进行查询优化
C.数据结构简单
D.有严格的数学基础

考点:内科主治医师内科专业实践能力三级信息管理技术笔试
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肺癌术后放射治疗适应证为()。

A.术后肿瘤残留者

B.手术标本切缘阳性

C.术后病理证实有肺门或纵隔淋巴结转移而清扫不彻底者

D.术中没有行区域淋巴结清扫

E.以上都是

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长25cm的玻璃管,两端开口,竖直插在水银槽内,露在槽内水银面外玻璃管的长度为13cm.现将上端管口封闭,然后将玻璃管竖直向上全部提出水银柱面外,若温度保持不变,大气压强为75cmHg,则存在管内的水银柱的长度为多长?

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发电机三相定子绕组,一般为星形连接,这主要是为了消除()。

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在起RBS6900设备时,若RUS的FAULT红灯和OPERATEONAL绿灯交替快闪,这表示()

A.光纤没接好

B.正在对该RRUS装载软件

C.RRUS没有收到时钟信号

D.RRUS坏了

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For many people today, reading is no longer relaxation. To keep up their work they must read letters, reports, trade publications, interoffice communications, not to mention newspapers and magazines: a never ending flood of words. In (1) a job or advancing in one, the ability to read and comprehend (2) can mean the difference between success and failure. Yet the unfortunate fact is that most of us are (3) readers. Most of us develop poor reading (4) at an early age, and never get over them. The main deficiency (5) in the actual stuff of language itself—words. Taken individually, words have (6) meaning until they are strung together into phrases, sentences and paragraphs. (7) , however, the untrained reader does not read groups of words. He laboriously reads one word at a time, often regressing to (8) words or passages. Regression, the tendency to look back over (9) you have just read, is a common bad habit in reading. Another habit which (10) down the speed of reading is vocalization—sounding each word either orally or mentally as (11) reads.
To overcome these bad habits, some reading clinics use a device called an (12) , which moves a bar(or curtain) down the page at a predetermined speed. The bar is set at a slightly faster rate (13) the reader finds comfortable, in order to "stretch" him. The accelerator forces the reader to read fast, (14) word by word reading, regression and subvocalization practically impossible. At first (15) is sacrificed for speed. But when you learn to read ideas and concepts, you will not only read faster, (16) your comprehension will improve. Many people have found (17) reading skill drastically improved after some training. (18) Charlie Au, a business manager, for instance. His reading rate was a reasonably good 172words a minute (19) the training; now it is an excellent 1,378 words a minute. He is delighted that how he can (20) a lot more reading material in a short period of time.

A.but
B.nor
C.or
D.for

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