关于神经胶质囊肿的表述正确的是（）
A.神经胶质囊肿是由胚胎时进化成白质的神经管成分发育障碍所致的先天性病变
B.囊肿可见于颅内任何部位，以额叶最常见，发病率极低
C.神经胶质囊肿被覆柱状上皮细胞或脉络丛细胞
D.CT检查呈脑脊液样密度或信号，增强后无强化
E.需与血管周围间隙扩大、脑囊虫病、脑穿通畸形囊肿和蛛网膜囊肿相鉴别
参考答案：A, B, C, D, E
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| A middle-aged woman in an old dress stepped hesitantly without an appointment into the president of Harvard University's outer office. The secretary could immediately _1_ that such a hick(乡下人) had no 2 at Harvard. "I want to see the president", she said softly. "He'll be_3_ all day," the secretary snapped. "I'll wait, " the woman replied. For hours, the secretary _4_her, hoping that she would finally become _5 and go away. She didn't. And the secretary finally had to disturb the president. The president _6_ appeared toward her. The woman told him, "I had a son that _7_ Harvard for one year but was accidentally killed. And I would like to put up a _8 for him, somewhere on campus". The president wasn't 9 but annoyed. "Madam," he said, "We can't put up a _10_ for every person who attended Harvard and _11_. If we did, this place would look like a cemetery(墓地)". "Oh, no," the woman explained 12 ," I don't want to erect a statue. I would like to give a building to Harvard." 13 at the old dress, the president _14 , "A building! Do you have any 15 idea how much a building costs? We have over eight million dollars in the physical(物质的) costs at Harvard". For a moment the woman was _16_. The president was pleased. He could get rid of her now. "Is that all it costs to start a _17_?" and then the woman asked quietly._18_ that Mrs. Leland Stanford walked away, traveling to Palo Alto, California where she _19_ the university that bears her _20_, a memorial to her son that Harvard no longer cared about. | ||||
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