题目内容
2.How can you find out what is going on inside a person's body without opening the patient's body up?Regular X rays can show a lot.CAT scans can show even more.They can give a complete view of body organs.What is a CAT scan?CAT stands for a kind of machine.It is a special X-ray machine that gets a 360-degree picture of a small area of a patient's body.
Doctors use X rays to study and determine diseases and injuries within the body,X rays can find a foreign object inside the body or take pictures of some inside organs to be X-rayed.
A CAT scanner,however,uses a group of X rays to give a cross-sectional(横截面)view of a specific part of the body.A fine group of X rays is scanned across the body and around the patient from many different directions.A computer studies the information from each direction and produces a clear cross-sectional picture on a screen.This picture is then photographed for later use.Several cross sections,taken one after another,can give clear"photos"of the entire body or of any body organs.The latest CAT scanners can even give clear pictures of active,moving organs,just as a fast-action camera can"stop the action",giving clear pictures of what appears unclear to the eye.And because of the 360-degree pictures,CAT scans show clear and complete views of organs in a manner that was once only shown during operation or examination of a dead patient.
Frequent appearance before X rays can cause skin burns,cancer or other damage to the body.Yet CAT scans actually don't cause the patient to more radiation than regular X rays do.CAT scans can also be done without getting something harmful into the patient,so they are less risky than regular X rays.
CAT scans provide exact,detailed information.They can quickly find such a thing as bleeding inside the brain.They are helping to save lives.
46.What is NOT true of a CAT scan?C
A.It is safer than regular X rays.
B.It makes use of computer techniques.
C.It can stop the action of an organ for a short time.
D.It gives clear pictures of active,moving body parts.
47.The underlined words"a foreign object"(Para 3)most probably refer to.D
A.a badly injured part inside the body
B.a new thing that is unknown to the doctor
C.a strange organ that has grown in the body
D.an object that gets inside the body by chance
48.What is the special use of the latest CAT scanners?A
A.It provides clear photos of moving organs.
B.It can take 3-dimension(三维)pictures of inside organs.
C.It won't cause serious skin burns,cancer or other damage to the body.
D.It helps to find out what is going on inside a person's body without opening it up.
49.We can infer from this passage that.A
A.patients in front of CAT may suffer from a bit of radiation
B.doctors need no opening-up of the body with CAT scanners
C.CAT scanners are more expensive than regular X-ray machines
D.CAT scanners can take photos of either the whole body or a part of it
50.The best title of this passage might be.B
A.the Newest Medical Invention
B.New X-ray Machine to Save Lives
C.How to Avoid the Damage of X Rays
D.Advantages and Disadvantages of CAT Scanners.
分析 这篇文章主要是介绍A CAT scanner的原理,优点以及在拯救生命方面的重大意义.
解答 46.C47.D48.A49.A50.B
46:C 细节认定题. 根据倒数第二段第二句话可知A项正确;根据第四段的A computer studies the information from each direction and produces a clear cross-sectional picture on a screen.可知B项正确;根据第四段中的The latest CAT scanners can even give clear pictures of active,moving organs,just as a fast-action camera can"stop the action",giving clear pictures of what appears unclear to the eye.可知C项错误,D项正确,故答案为C项.
47:D 推测词义题.画线词所在处是说医生可以利用X-rays找到患者体内的异物,故此题选D项.
48:A 细节认定题. 根据第四段中的"The latest CAT scanners can even give clear pictures of active,moving organs"可知选A项.
49:A 推理判断题. 根据倒数第二段中的Yet CAT scans actually don't cause the patient to more radiation than regular X-rays do.可以推出答案为A项.
50:B 标题选择题. 根据全文内容可知,本文主要介绍新型X-rays仪器在医学上的应用与优点,故选B项.
点评 阅读理解题测试考生在阅读基础上的逻辑推理能力,要求考生根据文章所述事件的逻辑关系,对未说明的趋势或结局作出合理的推断;或根据作者所阐述的观点理论,对文章未涉及的现象、事例给以解释.考生首先要仔细阅读短文,完整了解信息,准确把握作者观点.