有这样一种假说:冬眠是一种高度发达的机能.冬眠的哺乳动物虽然与人类一样都是温血动物,

题型:单项选择题

问题:

有这样一种假说:冬眠是一种高度发达的机能.冬眠的哺乳动物虽然与人类一样都是温血动物,但是它们在更宽范围的调节性上获得了进化,例如在体温调节上,就要比非冬眠动物强. 传统的研究认为,哺乳动物冬眠的奥秘在于心脏.无论冬眠动物,还是非冬眠动物,甚至人类,其心脏工作的原理是相同的.当钙离子流进心脏的细胞时,就引起心脏收缩;当钙离子随即排出细胞时,心脏又开始舒张.但是随着温度的降低,非冬眠动物的心脏细胞排除钙离子的能力明显降低,从而使心脏的舒张越来越困难,最后导致死亡;而此时冬眠动物的心脏细胞则完全与此相反.因此心脏细胞调节钙离子浓度的机制,是冬眠时心脏正常活动的关键所在.后来的研究证实,心脏细胞的这种变化还不是冬眠的根本原因,科学家们推测冬眠最终是由动物体内的遗传基因控制的.然而,人们却一直没有发现这种遗传基因.直到最近,日本科学家发现,在美洲松鼠等冬眠动物的血液中存在一种特殊的蛋白质HP.HP只能在冬眠动物身上找到,并与冬眠同步出现.这表明,HP在冬眠中具有重要的作用.那么,在人类身上也能找到类似冬眠的现象吗人类也可能冬眠吗答案是肯定的.人类在睡眠时也有体温降低、心跳放慢的现象,这在性质上与冬眠相似.而身体硕大的熊的冬眠,为实现人类的冬眠提供了可能.如果以HP为线索,也许能重新认识熊的冬眠.一旦控制熊冬眠的遗传基因得以破译,人的冬眠就不是不可能了.这样,人类就能把自己的代谢控制到最低极限,从而有利于癌症等疾病的长期治疗、未来的宇宙旅行等.

文中认为“HP在冬眠中具有重要的作用”,下列不能作为这一观点的根据的一项是______.

A.科学家们推测冬眠最终是由冬眠动物体内的遗传基因控制的

B.HP是在冬眠动物的血液中新发现的一种特殊的蛋白质

C.HP不能在非冬眠动物体内找到,而它的出现周期又跟冬眠动物的冬眠周期相同

D.在发现HP之前,人们一直没有发现动物体内控制冬眠的遗传基因

考点:在职联考GCT(语文)GCT(语文)37
题型:单项选择题

阅读理解。

     It was a cold and rainy afternoon in winter. Mr. Green was going to leave his office. He worked all day,

so he was very tired. He went out of the building and took out his key. When he reached "his car", he took

out a key to open the door. The door didn't open. It was very dark and he couldn't see clearly. He tried some

other cars, but none of them was his. Finally he reported to the police. But when he reached home, he found

his car was in front of his house. He didn't drive his car to work that morning.

1. The weather on that day was ______.

A. hot and rainy

B. cold and rainy

C. windy

D. fine

2. Mr. Green left his office ______. 

A. early

B. after a day's work

C. at half past three

D. after he found his car

3. He couldn't open the car door because ______.

A. he couldn't find his car key

B. it was very dark

C. he was too tired

D. his car was not here at all

4. Finally he ______.

A. asked the police to help him

B. didn't found his car

C. opened the car door

D. saw a policeman and he helped Mr. Green

5. Where did he find his car?

A. At the police station.

B. In the street.

C. At home.

D. He never found it.

题型:单项选择题

男性,38岁。4年前反复多次输血,近半年主诉乏力、低热、口腔及黏膜皮肤溃疡、平日易感冒,考虑为输血传播性疾病。首先要想到的是()。

A.艾滋病

B.肝炎

C.疟疾

D.梅毒

E.巨细胞病毒感染

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对于大学生来说,自觉把马克思主义作为自己行动的指南,就要做到()

A.坚持以阶级斗争为纲

B.在思想上自觉地坚持以马克思主义为指导,确立马克思主义的坚定信念,树立和坚定 * * 主义的远大理想

C.不断提高运用马克思主义立场、观点和方法分析、解决问题的能力,自觉辨别和抵制各种不良思想文化的影响

D.严格按照马克思主义的观点去做

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某学校在市绩效方案出台后,仍然违反有关规定滥发津贴、补贴、奖金等,按照《中 * * 党纪律处分条例》对直接责任者和领导责任者,情节严重的,给予()处分。

A.严重警告

B.撤销党内职务

C.留党察看

D.开除党籍

题型:单项选择题

下列药物中,可增强双香豆素类抗凝剂抗凝作用的是()

A.保泰松

B.甲硝唑

C.西咪替丁

D.广谱抗生素

E.巴比妥类药物

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