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The Discovery of Penicillin (青霉素) In the autumn of 1928, a Scottish scientist Alexander Fleming was searching for a substance that would kill fatal germs(细菌). On his desk were small plates containing the germs. (51) evening, he forgot to cover one of the plates. When he arrived the next morning, he found a spot of green mould(霉菌)in one plate. This is not strange because the room was rather damp(潮湿) ,with (52) one window. But Fleming did not throw out the spoiled plate, be cause something unusual caught (53) attention. On the uncovered plate, near the green mould, the germs (54) . That meant that the mould had killed the germs there. Fleming watched the mould grow (55) several days. As the green mould spread, it killed more and (56) germs. Fleming began to study the mysterious mould. It grew and grew. Then he noticed tiny drops of liquid on the suce of the mould. Perhaps this was the chemical that was destroying the germs. Fleming drew off the liquid, drop by drop. He put this liquid in a test tube, and it (57) the germs in the tube. He called the (58) penicillin. Fleming published his finding in a British medical journal (59) 1929. But for ten years, while he continued to experiment with penicillin, his discovery was largely ignored near the medical world. Then in 1938 a team of British scientists happened to (60) about Fleming’s findings in an old medical journal. They made further (61) with the drug. They tested it on animals and then (62) human beings. In 1941, it was declared safe for use on humans. Soon penicillin was produced in large quantity and was used to (63) many infections(感染). Penicillin is a very powerful drug. () can treat many kinds of infections. However, it has some bad effects. Sometimes it causes a skin problem or a light fever. And it can be fatal for people (65) are allergic(过敏性的)to it. That is why before you take a penicillin shot, the doctor gives you a test shot first.