为γ-氨基丁酸的环状衍生物，可促进乙酰胆碱合成的改善脑功能药物是
A．盐酸多奈哌齐
B．利斯的明
C．吡拉西坦
D．石杉碱甲
E．氢溴酸加兰他敏
参考答案：C
解析： 本题考查改善脑功能的药物。 吡拉西坦属广氨基丁酸的环状衍生物。本药的确切机制尚不清楚，且多有争议。但它能促进脑内二磷酸腺苷(ADP)转化为三磷酸腺苷(ATP)，使脑内能量供应状况改善，还能影响胆碱能神经元的兴奋传递，促进乙酰胆碱合成。可改善轻度及中度老年痴呆者的认知能力，但对重度痴呆者无效。还可用于治疗脑外伤所致记忆障碍及弱智儿童。
用方框中所给词语的适当形式填空，使文章完整、通顺。（每词限用一次）
Before you are allowed to have a full license, you have to take a driving test. You can take a test in your 小题5: car, but it has to be fit for the road. In the test you have to drive round for about half an hour and then 小题6: a few questions. If you don't pass the test, you are allowed to take it again a few weeks 小题7: if you want to. In 1970 a woman passed her 小题8: test after 212 driving lessons. When you've passed your test, you don't have to take it again, and you are allowed to go on driving as long as you like. Britain's小题9: driver was a man who drove in 1974 at the age of 100. Before 1904 everyone was allowed to drive, even children. Then from 1904 car drivers had to have a license. But they didn't have to take a test小题10: 1935. On the early days of car driving, before 1878, cars weren't allowed to go faster than four miles an hour, and someone had to lead the car with a red flag. |