Have you ever been swimming in a pond, stream, or lake and had a leech(水蛭) stick on you? You probably shouted and tried to force it away as fast as you could. But leeches aren’t really sick, and sometimes they can save lives.
In ancient Egypt and later medieval(中世紀(jì)) Europe, doctors put leeches on patients. They believed that the spineless wormlike living things can cure all kinds of illnesses by sucking(吮吸) a patient’s blood. In Europe and in the United States, millions of leeches were used throughout the 1800s. Doctors used leeches to treat a number of illnesses, from obesity to headaches. People soon learned that leeches could not cure most diseases and were not a good treatment for patients. However in 1985, a Harvard University doctor changed people’s thinking once again. He was trying to reattach(重新接上) a patient’s ear, which had been cut off. He had trouble reconnecting the veins because the patient’s blood kept clotting(凝). He used a leech to draw out the blood and saved the ear.
Since then, leeches have often been used in surgery where body parts are reattached. During surgery, a leech is placed on the area where the surgeon does not want the blood to pool and clot. Then the leech produces a thing that keeps the veins(靜脈) open and stops the blood from clotting. The leech sucks up excess blood, allowing fresh blood to flow, which helps the patient get well.
Some people are scared to death at the thought of having a blood sucking thing attached to them. But why not welcome a leech if it can save your life?
1.What is the passage mostly about?
A.Patient’s interest in leeches.
B.How and where leeches live.
C.The medical uses of leeches.
D.Leeches in ancient medicine.
2.When were leeches first used?
A.In medieval Europe.
B.In ancient Egypt.
C.In 1985 by a Harvard University doctor.
D.In the 1800s in Europe and in the United States.
3.When a leech is placed on a patient, which one happens first?
A.The leech produces a thing.
B.The patient’s veins open.
C.The patient’s blood flow faster
D.The leech sucks up excess blood.
4.Why did a doctor in 1985 decide to try using leeches?
A.He needed a way to close the wound.
B.He wanted to change people’s thought.
C.He believed in the mystery of nature.
D.He needed to keep blood from clotting