下面关于微处理器的叙述中,不正确的是________。A.微处理器通常以单片集成电路

题型:单项选择题

问题:

下面关于微处理器的叙述中,不正确的是________。

A.微处理器通常以单片集成电路制成

B.它至少具有运算和控制功能,但不具备存储功能

C.Pentium是目前PC机中使用最广泛的一种微处理器

D.Intel公司是国际上研制、生产微处理器最有名的公司

考点:计算机等级考试网络技术三级网络技术笔试72
题型:单项选择题

肺心病与慢性支气管炎、肺气肿的临床征象有很多相似点,但不同点是肺心病具有()

A.呼吸困难、发绀

B.严重肺气肿的体征

C.肺动脉高压和右心室增大的征象

D.血气分析PaO2<60mmHg,PaCO2>50mmHg

E.X线检查显示双肺纹理增多,肺野透亮度增加

题型:单项选择题

阅读理解。

     I'm a skeptic (怀疑论者) when it comes to the benefits of taking vitamins and other supplements. We

swallow far more than any other country- yet we're not the healthiest folks by far, nor do we live the longest.

     There's more bad news for vitamins this week: Turns out that taking folic acid (叶酸) and vitamin B12

supplements doesn't prevent heart attacks or death, according to a major new study in the Journal of the

American Medical Association. It was hoped they would, since the vitamins do reduce levels of homocysteine (高半胱氨酸), an amino acid (氨基酸) that is higher in the blood of people who have a higher risk of heart

disease. In fact, homocysteine was reduced 30 percent after one year of treatment in the participants who

took both vitamins. But in the following three years, just as many vitamin takers died as those who didn't take

the vitamins. Even worse, the study was stopped early because another similar study suggested that there may

be an increased risk of cancer from taking B vitamins.

      I had been taking a health-food store monster multivitamin (综合维生素剂) for months. Coincidentally, I

had been experiencing some strange numbness in my legs that was starting to scare me. I remember sitting in

a long meeting with my ankles crossed, and when I tried to stand up I crumpled on the floor and hit my chin

on the glass coffee table because my leg had gone completely numb and worthless. As I sat there and shook

my leg, I got that"pins and needles" feeling and soon was OK. But it scared me enough to make an appointment with a neurologist, who suggested an MRI to rule out stroke, or a brain tumor(肿).

     While I'll never know for sure if the vitamins caused my problem, many, many studies have reminded us

that pill forms of vitamins and minerals don't provide the same benefit as getting them from food. There's a lot

we don't know about how the human body works. Until we know more, I'm getting most of my vitamins from

the farmer's market.

1. What can we know from the last paragraph?

A. The writer is getting most of pill forms of vitamins from the markets.

B. The writer continues to take vitamins in great quantities.

C. The writer is getting vitamins from food, which can provide more benefits.

D. The writer will never take pill forms of vitamins and minerals.

2. Why do people take folic acid and vitamin B12 supplements?

A. They want to stop heart attacks or live longer.

B. They want to live longer.

C. They want to increase risk of cancer.

D. They want to experience some strange numbness.

3. Which of the following is not true according to the passage?

A. It was the multivitamin he took that caused the writer to get the "pins and needles" feeling.

B. Taking more vitamins will not make a man healthier or live longer.

C. The vitamins can reduce levels of homocysteine in our body.

D. The less homocysteine in our blood, the less chance we'll have heart attacks.

4. The best title of the passage can be ______.

A. Vitamins: Benefit Us a Lot

B. Vitamins: No Help for Your Heart

C. Vitamins: Bad for the Brain, Too

D. Some Bad News About Vitamins.

题型:单项选择题

铰链四杆机构的压力角是指在不计算摩擦情况下连杆作用于()上的力与该力作用点速度所夹的锐角。

A.主动件

B.从动件

C.机架

D.连架杆

题型:单项选择题

影响龋病流行的最主要因素之一是()

A.钙磷摄入的比例与摄入量

B.就诊的医疗级别与次数

C.钙的摄入量与摄入频率

D.糖的摄入量与摄入频率

E.刷牙的时间与频率

题型:单项选择题

下列疾病出现发热,不属于感染性的是()

A.肺脓肿

B.大叶性肺炎

C.流行性脑脊髓膜炎

D.伤寒

E.风湿热

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