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Modern scientists divide the process of dying into two stages—clinical or
(emporary 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 (hat 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(新成代谢) , 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 an 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.
26. This passage focuses on_______.
A. the difference between biological and clinical death.
B. the process of dying
C. prolonging the period of clinical death
D. the nature of clinical death
27. The best statement of the main idea of this passage is that_______.
A. modem scientists divide the process of dying into clinical and
biological death
B. biological death occurs when vital organs have suffered permanent
damage
C. scientists have found a way to prolong the period of clinical death
D. cooling delays the processes leading to biological death
28. One characteristic of clinical death is______.
A. lasting damage to the lungs B. destruction of the tissues
C. temporary non-functioning of the heartD. that the organism cannot be
revived
29. According to the passage, cooling an organism_______.
A. speeds up the body's metabolism B. slows disintegration of body
tissues
C. prevents damage to organs D. revives damaged organs
30. One possible benefit of the experiment discussed in the passage
is______.
A. less crowded cities B. victory over death
C. protection against fatal injury D. fewer deaths from heart attacks
答案：26. C 27. C 28. C 29. B 30. D
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发表于 2016-7-11 18:45:56