阅读理解

Directions: There are 4 passages followed by some questions or unfinished statements, you should answer the questions or decide on the best choice on the Answer Sheet.

Passage 3

There is a great deal of controversy within the medical profession regarding the use and value of the coronary bypass procedure, and for more than eight years the American Heart Association has discussed the question at its regular scientific sessions.

The bypass operation consists of open heart surgery in which the physician takes a vein from the patient’ s leg and implants it near the heart to construct a passage around the blockage in a clogged artery so that blood can flow freely by. The operation performed on about 100, 000 persons a year in the US and costs approximately $10, 000. The procedure is designed to relieve the pain of angina pectoris which occurs when the blood supply’ s obstructed and also to allow the patient more freedom of sustained activity.

In persons with advanced heart disease and blockage in several arteries, the bypass operation is considered by most doctors to be the preferable means of prolonging life. In the case of those with a less advanced disease, or where only one artery is involved, the advisability of the procedure is much more controversial. The operation doesn’ t cure the disease that caused the blocked artery in the first place. According to some studies, somewhere around half of the patients have another blocked artery within five years, and in some cases even within one year.

There is of course a mortality rate in any major operation which varies from physician to physician and hospital to hospital. The danger to the patient is greatly increased if he is in generally poor condition, very advanced in age, or suffering from some serious or debilitating illness. It is essential that the operation be performed by a skilled surgeon knowledgeable about this particular technique and in a hospital with the best possible facilities for his use.

问答题 What is a coronary bypass?

【正确答案】An operation to construct a passage around the blockage in a clogged artery.

【答案解析】根据第二段第一句话“The bypass operation consists of open heart surgery in which the physician takes a vein from the patient’ s leg and implants it near the heart to construct a passage around the blockage in a clogged artery so that blood can flow freely by. ” 我们可知搭桥手术是一项需要打开心脏的外科手术，医生从病人的腿部取出一根血管，再将其移植到心脏附近，于动脉堵塞处搭建一条通道，血液就可以自由流动了。

问答题 How does the medical profession regard the bypass operation?

【正确答案】Many doctors question the advisability of its use where only one artery is affected.

【答案解析】根据第三段第二句话“In the case of those with a less advanced disease, or where only one artery is involved,the advisability of the procedure is much more controversial. ” 有些心脏病没有那么严重，有些只有一条动脉堵塞，所以医生们认为这些情况下病人要不要手术是比较有争议的。

问答题 What are the usual results of the bypass operation?

【正确答案】The patient is relieved of pain.

【答案解析】根据第二段最后一句话“The procedure is designed to relieve the pain of angina pectoris which occurs when the blood supply’ s obstructed and also to allow the patient more freedom of sustained activity. ” 我们知道手术只能减轻供血不足导致的心绞痛，让病人可以多活动活动。

问答题 Under what conditions should the bypass operation be performed?

【正确答案】When the patients can be expected to show favorable results.

【答案解析】根据第三段，第三段讲的是不宜进行搭桥手术的情况，根据最后一句话“According to some studies, somewhere around half of the patients have another blocked artery within five years, and in some cases even within one year. ” 我们可知，必须得是在病人有望恢复的情况下，搭桥手术才可进行。

问答题 What can ensure the bypass operation?

【正确答案】A skilled surgeon knowledgeable about this particular technique and in a hospital with the best possible facilities for his use.

【答案解析】根据最后一段，我们可知，搭桥手术能否成功还要看病人的身体状态，但基本条件是医生得了解这种手术，而且医院的设备必须达到一定水平才行。