Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 36 to 42.
Jonas Salk is the American physician and medical researcher who developed the first safe and effective vaccine for poliomyelitis. Salk received his M.D. in 1939 from New York University College of Medicine, where he worked with Thomas Francis Jr., who was studying how to develop vaccines from killed viruses. Salk joined Francis in 1942 at the University of Michigan School of Public Health and became part of a group that was working to develop a vaccine against influenza.
In 1947, Salk became associate professor of bacteriology and head of the Virus Research Laboratory at the University of Pittsburgh School of Medicine, where he began research on poliomyelitis. Working with scientists from other universities in a program to classify the various strains of the polio virus, Salk corroboratedother studies in identifying three separate strains. He then demonstrated that killed virus of each of the three, although incapable of producing the disease, could induce antibody formation in monkeys.
In 1952, he conducted field tests of his killed-virus vaccine, first on children who had recovered from polio and then on subjects who had not had the disease. The results of both tests showed that the children’s antibody levels rose significantly and no subjects contracted polio from the vaccine. His findings were published the following year in the Journal of the American Medical Association. In 1954, a mass field trial was held, and the vaccine, injected by needle, was found to safely reduce the incidence of polio. On April 12,1955, the vaccine was released for use in the United States. Salk served successively as professor of bacteriology, preventive medicine, and experimental medicine at Pittsburgh, and in 1963, he became fellow and director of the Institute for Biological Studies in San Diego, California, later called the Salk Institute. Among many other honors, he was awarded the Presidential Medal of Freedom in 1977.
What is the main idea of the passage?
A. How Jonas Salk trained to be a physician and medical researcher
B. How the medical research of Jonas Salk led to the development of the polio vaccine
D.How Salk was promoted to important positions at the University of Pennsylvania
C.How Salk and his colleagues learned to kill viruses
Giải bởi Vietjack
Chọn đáp án B
Ý chính của bài đọc là gì?
A. Jonas Salk được đào tạo để trở thành một bác sĩ và nhà nghiên cứu y học như thế nào
B. Nghiên cứu y học của Jonas Salk đã dẫn đến sự phát triển của vắc xin bại liệt như thế nào
C. Salk và các đồng nghiệp của anh ấy học cách tiêu diệt virus như thế nào
D. Salk được thăng chức vào các vị trí quan trọng tại Đại học Pennsylvania như thế nào
Thông tin trong bài: "Jonas Salk is the American physician and medical researcher who developed the first safe and effective vaccine for poliomyelitis." (Jonas Salk là bác sĩ và nhà nghiên cứu y học người Mỹ, người đã phát triển loại vắc-xin đầu tiên an toàn và hiệu quả cho bệnh bại liệt.)
- "In 1947, Salk became associate professor of bacteriology and head of the Virus Research Laboratory at the University of Pittsburgh School of Medicine, where he began research on poliomyelitis." (Năm 1947, Salk trở thành phó giáo sư vi khuẩn học và là người đứng đầu Phòng thí nghiệm Nghiên cứu Virus tại Trường Đại học Y Pittsburgh, nơi ông bắt đầu nghiên cứu về bệnh bại liệt.)
- "On April 12,1955, the vaccine was released for use in the United States." (Vào ngày 12 tháng 4 năm 1955, vắc-xin đã được được đưa vào sử dụng tại Mỹ.)
Instant messaging enables you to get (26) ____________touch with somebody immediately and talk in real time to that person in a (27) ____________artificial while seemingly urgent way.
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions.
You needn't hurry because there is a delay of about two hours.
A. There is a delay of about two hours and therefore you mustn't hurry.
C. It is not necessary for you to hurry because there is a delay of about two hours.
D. You mustn't hurry because there is a delay of about two hours.
What do bank tellers do?
A. They are in charge of the bank branch
B. They help the customers
D. They protect the money
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.
You'd better take the keys. It’s possible I'll come home late.
A. You'd better take the keys as I possibly come home late.
B. You'd better take the keys in case I come home late.
C. I'll probably come home late so that you'd better take the keys.
Mark the letter A, B, C, or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions.
All of the following statements about the killed virus vaccine are true EXCEPT____________.
A. it did not induce antibody formation in monkeys
B. it had three strains that scientists worked with
D. it helped monkeys form antibodies
If you're angry with one another (or even if you're not), you may end (28) ____________typing something that you might not have said if you had a little longer to think it through.
Mark the letter A, B, C, or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions.
