Two groups of scientists demonstrated last week for the first time that the

游客2023-09-01  24

问题     Two groups of scientists demonstrated last week for the first time that the body launches a massive, effective counter-attack on the virus soon after infection of HIV begins. If doctors can figure out how to reproduce that early, powerful immune response, they might be able to develop better treatments to (47)______ stages of the disease. The researchers should be (48)______—and more than a bit of luck. After all, to study someone at the beginning of a relatively (49)______ phase of the HIV infection, they had to find people who did not yet realize they had contracted the virus. It (50)______ that at least a third of HIV-infected people develop a fever or a severe sore throat within a few weeks to months after first (51)______. Such signs, which usually clear up in their own, can easily be (52)______ as a bad flu. In order to identify seven young men suffering from a primary HIV infection, the researchers took this project by (53)______ in hospital emergency rooms and talking to colleagues.
    Using advanced laboratory tests that had been developed only in the past few years, both sets of scientists discovered an (54)______ growth of virus in the men’s blood streams. Each liter of the men’s blood contained as many as 10 million infectious viruses.
    Within days after the virus burst, the researchers measured a rapid increase in the bloodstream of the number of anti-HIV antibodies(抗体). These Y-shaped bits of protein sought out the virus and targeted it for (55)______. Once the antibody attack reached full scale in the seven test subjects, the level of HIV in the bloodstream dropped (56)______. In the majority of cases, the researchers could detect little or no virus two to three weeks later. In other words, the normal immune system can shut down the AIDS virus. Now researchers must figure out exactly how the body puts together this early effective defense and how the virus manages, years later, to avoid it.

                  Word Bank:
A. destruction                 I. abruptly
B. interrupt                   J. segregation
C. impair                      K. testifies
D. residing                    L. lively
E. misdiagnosed                M. explosive
F. exemplified                 N. silent
G. persistent                  O. exhausting
H. exposure
[br]

选项

答案 A

解析 此处应填名词.本句的主语Y-shaped bits of protein指的就是上句中的antibodies。通过下句中的Once the antibody attack reached…,the level of HIV in the bloodstream dropped可知,Y-shaped bits of protein的作用就是搜出HIV病毒并将其设为目标杀死,故A. destruction“破坏,毁灭”符合题意。J. segregation“隔离”与下句中的内容矛盾:只将病毒隔离起来是不能减少病毒数目的。
转载请注明原文地址:https://tihaiku.com/zcyy/2975189.html
最新回复(0)