For several years, scientists have been testing a substance called interferon(干扰素), a potential wonder drug that is proving to b

admin2013-11-30  29

问题     For several years, scientists have been testing a substance called interferon(干扰素), a potential wonder drug that is proving to be effective in treating a variety of ailments, including virus infections, bacteria infections, and tumors. To date, the new drug has provoked no negative reaction of sufficient significance to discourage its use. But in spite of its success, last year only one gram was produced in the entire world.
    The reason for the scarcity lies in the structure of interferon. A species of specific protein, the interferon produced from one animal species cannot be used in treating another animal species. In other words, to treat human beings, only interferon produced by human beings may be used. The drug is produced by infecting white blood cells with a virus. Fortunately, it is so powerful that the amount given each patient per injection is very small.
    Unlike antibiotics, interferon does not attack germs directly. Instead, it makes unaffected cells resistant to infection, and prevents the multiplication of viruses within cells.
    As you might conclude, one of the most dramatic uses of interferon has been in the treatment of cancer. Dr. Hans Strander, research physician at Sweden’ s famous Karolinska Institute, has treated more than one hundred cancer patients with the new drug. Among a group of selected patients who has undergone surgical procedures for advanced cancer, half were given interferon. The survival rate over a three-year period was 70 percent among those who were treated with interferon as compared with only 10 to 30 percent among those who have received the conventional treatments.
    In the United States, a large-scale project supported by the American Cancer Society is now underway. If the experiment is successful, interferon could become one of the greatest medical discoveries of our time.
Which of the following is true of the results of Dr. Strander’ s experiments?

选项 A、Both interferon and conventional treatments should be used to ensure the survival of the patients.
B、At the end of three years, only ten to thirty percent of the patients who had not received interferon died.
C、Only the patients who received interferon survived.
D、Most of the patients who were treated with interferon survived.

答案D

解析 第四段,作者阐述了Dr.Hans Strander利用interferon治疗癌症患者这一事例,指出三年内接受该药物治疗的患者存活率达到70%以上,而接受传统治疗的患者存活率仅为10%至30%,选项B、C与这一意思相矛盾,不正确;本段只是为了说明interferon对于癌症的显著疗效,并未表达“interferon和传统疗法都应该应用”这层意思,因此选项A也不符合;只有选项D“接受interferon治疗的患者大部分都幸存下来”与原文意思一致。
转载请注明原文地址:https://jikaoti.com/ti/ZdNDFFFM
0

最新回复(0)