问题 单项选择题

男,25岁,一年来牙龈逐渐肿大。检查发现:全口牙龈 * * 及龈缘肿,上下前牙明显。龈 * * 球状突起,前牙龈呈分叶状质地坚硬,略有弹性,呈粉红色,不出血,无疼痛,龈沟加深,有菌斑,无分泌,部分冠折断,已作根管治疗。

上述检查仍不能确诊,在用药史上还需了解的是()

A.全身用药

B.抗癫痫药物

C.非激素类药物

D.抗厌氧菌药物

E.局部用药

答案

参考答案:B

单项选择题
阅读理解

阅读理解

     Believe it or not, optical illusion(错觉) can cut highway crashes.

    Japan is a case in point. It has reduced automobile crashes on some roads by nearly 75 percent using

a simple optical illusion. But stripes, called chevrons(人字形), painted on the roads make drivers think

that they are driving faster than they really are, and thus drivers slow down.

     Now the American Automobile Association Foundation for Traffic Safety in Washington D.C. is

planning to repeat Japan's success. Starting next year, the foundation will paint chevrons and other

patterns of stripes on selected roads around the country to test how well the patterns reduce highway

crashes.

    Excessive (too great) speed plays a major role in as much as one fifth of all fatal traffic accidents,

according to the foundation. To help reduce those accidents, the foundation will conduct its tests in areas

where speed-related hazards (danger) are the greatest curves, exit slopes, traffic circles, and bridges.

    Some studies suggest that straight, horizontal bars painted across roads can initially cut the average

speed of drivers in half. However, traffic often returns to full speed within months as drivers become used

to seeing the painted bars.

     Chevrons, scientists say, not only give drivers the impression that they are driving faster than they

really are but also make a lane appear to be narrower. The result is a longer lasting reduction in highway

speed and the number of traffic accidents.

1. On roads painted with chevrons, drivers tend to feel that ________.

A. they should avoid driving fast.      

B. they are driving in the wrong lane

C. they should slow down their speed    

D. they are coming near to the speed limit

2. The advantage of chevrons over straight, horizontal bars is that the former ________.

A. can keep drivers awake          

B. can cut road accidents in half

C. will look more attractive          

D. will have a longer effect on drivers

3. What does the American Automobile Association Foundation for Traffic Safety do?

A. change the road signs across the country  

B. try out the Japanese method in certain areas

C. replace straight, horizontal bars with chevrons  

D. repeat the Japanese road patterns

4. What of the following is true about straight, horizontal bars painted across roads?

A. They are suitable only on broad roads.

B. They are falling out of use in the United States.

C. They cannot be used successfully to traffic circles.

D. They are ignored in a long period of time.

5. What's the best title of the passage?

A. a new pattern for painting highways    

B. a new way of highway speed control

C. a new way of training drivers            

D. a new type of optical illusion