Modern scientists divide the process of dying into two stages-clinical or te

游客2023-07-18  8

问题     Modern scientists divide the process of dying into two stages-clinical or temporary death and biological death. Clinical death occurs when the vital organs, such as the heart or lungs, have ceased to function, but have not suffered permanent damage. The organism can still be revived (复活). Biological death occurs when changes in the organism lead to the disintegration (解体) of vital cells and tissues. Death is then irreversible and final.
    Scientists have been seeking a way to prolong the period of clinical death so that the organism can be revived before biological death occurs. The best method developed so far involves cooling of the organism, combined with narcotic(麻醉的) sleep. By slowing down the body’s metabolism(新陈代谢), cooling delays the processes leading to biological death.
    To illustrate how this works, scientists performed an experiment on a six-year-old female monkey called Keta. The scientists put Keta to sleep with a narcotic. Then they surrounded her body with ice-bags and began checking her body temperature. When it had dropped to 28 degrees the scientists began draining blood from its body. The monkey’s blood pressure decreased and an hour later both the heart and breathing stopped; clinical death set in. For twenty minutes Keta remained in this state. Her temperature dropped to 22 degrees. At this point the scientists pumped blood into its body in the direction of the heart and started artificial breathing. After two minutes the monkey’s heart became active once more. After fifteen minutes, spontaneous breathing began, and after four hours Keta opened her eyes and lifted her head. After six hours, when the scientists tried to give her a penicillin injection, Keta seized the syringe and ran with it around the room. Her behavior differed little from that of a healthy animal. [br] One possible benefit of the experiment discussed in the passage is______.

选项 A、less crowded cities
B、victory over death
C、protection against fatal injury
D、fewer deaths from heart attacks

答案 D

解析 可定位在第3段的具体实验过程,一只6岁大的母猴被麻醉,继而用冰袋冷却其躯体,体温降到28度时开始抽血,在临床死亡阶段又为它输血并做人工呼吸,并成功救活这只猴子,题干问:“这个实验可能产生的益处在于……”,选项A为“减少城市拥挤”,这能通过减少人口实现,而实验目的在于“救人于临床死亡阶段”而非“减少人口”,故不正确;选项B为“战胜死亡”,目前还没有任何医学科技宣称能做到这一点,也不正确;选项C为“保护人们免受致命伤害”,文中并未提及;选项D为“减少心脏病发病死亡人数”,而心脏的功能与实验中的抽血和输血相一致,故选项D为正确答案。
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