问题 单项选择题 B型题

可在原核细胞中表达,在人体内穿透力强的是()。

A.抗体融合蛋白

B.双特异性抗体

C.人源化抗体

D.小分子抗体

E.抗体库技术

答案

参考答案:D

解析:人源化抗体、小分子抗体、抗体融合蛋白、双特异性抗体及抗体库技术均为基因工程抗体技术。人源化抗体保留了亲本鼠单克隆抗体的亲和力和特异性,降低了异源性,有利于人体应用。小分子抗体的分子量小,可在大肠杆菌等原核细胞表达,在人体内穿透力强,有利于疾病的治疗。抗体融合蛋白将抗体分子片段与其他蛋白融合,可将生物活性物质导向靶细胞特定部位,所谓"生物导弹"。双特异性抗体能同时结合两种抗原,因而可介导标记物与靶抗原结合或效应因子定位于靶细胞,在免疫学检测中可简化操作步骤,提高检验质量。

选择题
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     In recent years many countries have been faced with the problem of how to make their workers more

productive. Some experts believe that the answer is to make jobs more varied. Do more varied jobs lead

to greater productivity? There is something to suggest that while variety certainly makes the worker's life

more enjoyable, it does not make him work harder. So variety is not important.

     Other experts feel that giving the worker freedom to do his job in his own way is important and there

is no doubt that this is true. The problem is that this kind of freedom cannot easily be given in the modern

factory with its complicated machinery which must be used in a fixed way. Thus while freedom of choice

may be important, there is very little that can be done to achieve this.

     Another important consideration is how much each worker contributes to the product he is making. In

most factories the worker sees only one small part of the product. Some car factories are said to be

experimenting with having many small production lines rather than a large one, so that each worker

contributes more to the production of the cars on his line. It would seem then that the degree of workers'

contribution is important.

     To what extent does more money lead to greater productivity? The workers themselves cartainly think

this is important, but perhaps they want more money only because the work they do is so boring. Money

just lets them enjoy their spare time more. A similar argument may explain demands for shorter working

hours. Perhaps if companies succeed in making workers' jobs more interesting, they will neither want

more money, nor will shorter working hours be so important to them.

1. Which of the following things will not increase productivity?

A. Making jobs more varied.

B. Giving workers freedom to do their jobs in their own way.

C. Increasing workers' contribution to production.

D. Longer working hours.

2. The last sentence in this passage means that if companies manage to make workers'jobs more

interesting, ________.

A. they will want more money

B. they will demand shorter working hours

C. more money and shorter working hours are important

D. more money and shorter working hours will not be so important to them

3. In this passage, the writer tells us________.

A. how to make workers more productive

B. possible factors leading to greater productivity

C. more money leads to greater productivity

D. how to make workers' jobs more interesting