问题
单项选择题
硝苯地平抗心绞痛作用的主要机理是( )
A．降低心脏后负荷，减少心肌耗氧量
B．降低心脏前后负荷，减少心肌耗氧量
C．扩张冠状动脉，抑制心肌收缩，减少心肌耗氧量
D．减慢心率，减弱心肌收缩力，减少心肌耗氧量
E．降低血浆肾素活性，扩张周围血管，减少心肌耗氧量
答案
参考答案：C
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硝苯地平抗心绞痛作用的主要机理是( )
A．降低心脏后负荷，减少心肌耗氧量
B．降低心脏前后负荷，减少心肌耗氧量
C．扩张冠状动脉，抑制心肌收缩，减少心肌耗氧量
D．减慢心率，减弱心肌收缩力，减少心肌耗氧量
E．降低血浆肾素活性，扩张周围血管，减少心肌耗氧量
参考答案：C
| Questions 91-95 are based on the following passage. It is amazing how many people still say, "I never dream", for it is now decades since it was established that everyone has over a thousand dreams a year, however few of these nocturnal productions are remembered on waking. Even the most confined "non-dreamers" will remember dreams if woken up systematically during the Rapid Eye Movement (REM) periods. These are periods of light sleep during which the eyeballs move rapidly back and forth under the closed lids and the brain becomes highly activated, which happens three or four times every night of normal sleep. It is a very interesting question why some people remember dreams regularly—perhaps several a night on occasion—while others remember hardly any at all under normal conditions. In considering this, it is important to bear in mind that the dream tends to be an elusive phenomenon for all of us. We normally never recall a dream unless we awaken directly from it, and even then it has a tendency to fade quickly into oblivion. Given this general elusiveness of dreams, the basic factor that seems to determine whether a person remembers them or not is the same as that which determines all other memory, namely degree of interest. Dream researchers have made a broad classification of people into "recallers" —those who remember at least one dream a month—and "non-recallers", who remember fewer than this. Tests have shown that cool, analytical people with a very rational approach to their feelings tend to recall fewer dreams than those whose attitude to life is open and flexible. Engineers generally recall fewer dreams than artists. It is not surprising to discover that in western society, women normally recall more dreams than men, since women are traditionally allowed an instinctive, feeling approach to life. In modern urban-industrial culture, feeling and dreams tend to be treated as frivolities which must be firmly subordinated to the realities of life. We pay lip-service to the inner life of imagination as it expresses itself in the arts, but in practice relegate music, poetry, drama and painting to the level of spare-time activities, valued mainly for the extent to which they refresh us for a return to work. We discourage our children from paying much attention to anything that might detract from the serious business of studying for exams or making a living in the "real" world of industry and commerce. |
During REM periods, people ______.
A．dream less
B．wake up more easily
C．remember their dreams more clearly
D．experience discomfort