《英语流行话题阅读:语境识词3500》Unit 16 什么是癌症?

　　Unit 16
What Is Cancer?
As you probably know from the appeals being made for funds to fight cancer, and from all the research that is being down on this subject -- cancer is a great threat to the health and life of mankind. We will only discuss cancer in general terms, so you can have a general idea of what happens in a body that has cancer.
A cancer is a continuous growth in the body which does not follow the normal growth pattern. The cells forming the cancer spread through the body to parts which may be far from the spot where the cancer began. Unless it is removed or destroyed, the cancer can lead to the death of the person.
Cells in the body are growing all the time. As they wear out and disappear, their places are taken by new cells of exactly the same kind. But cancer cells look and act differently from normal body cells. They look like the young cells of the part of the body where they started -- but different enough to be recognized as cancer when seen through a microscope.
When these cancer cells divide and increase in number, they don't change into the fully¹ grown form and then stop reproducing². Instead, they remain young cells and continue to increase in number until they are harmful.
As cancer cells grow, they do not remain in one spot, but separate and move in among the normal cells. They may become so numerous that the normal cells in this part of the body cannot  continue to work or even remain alive. When the cancer gets into the blood, it is carried to distant parts of the body. There it may grow to form large masses which interfere³ with the activities of the normal cells.
Unless the growth and spread of the cancer is stopped, the patient will die. That is why it is important to have periodic⁴ examinations to detect and treat cancer before it has spread too far.
Cancers are not spread from man to man by contact. No drug has been found that cures completely and is useful for all kinds of cancer. One of medicine's greatest goals is to understand fully the nature and cause of cancer, and to find a way to prevent and cure it.

1 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

2 reproducing   

复制( reproduce的现在分词 )； 重现； 再版； 生殖

参考例句：

• Mind has become self-reproducing through man's capacity to transmit experience and its products cumulatively. 通过传递生活经验和积累创造的产品，人类的智慧在不断地进行着自我丰富。
• Spores form a lipid membrane during the process of reproducing. 孢于在生殖过程中形成类脂膜。 来自英汉非文学 - 生命科学 - 预防生物武器

3 interfere   

v.(in)干涉，干预；(with)妨碍，打扰

参考例句：

• If we interfere, it may do more harm than good.如果我们干预的话，可能弊多利少。
• When others interfere in the affair,it always makes troubles. 别人一卷入这一事件，棘手的事情就来了。

4 periodic   

adj.周期的，定期的，时而发生的

参考例句：

• Long long ago,we knew the periodic motion of a planet.很久以前，我们就知道行星的周期运动。
• These arrangements are subject to periodic reviews.这几项安排每隔一定时间须予复查。