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问题 单项选择题

下列有关生物技术和生物工程的叙述，正确的是（）

A.制作果醋时，必须向发酵装置不断补充氧气

B.固定化酵母细胞用CaCl2溶液作载体

C.在进行植物组织培养和动物细胞培养时，细胞都必须先进行脱分化

D.基因表达载体中的复制原点处比较容易打开双链，是因为它位于基因的首端，是RNA聚合酶识别和结合的部位

答案

参考答案：A

单项选择题

某妇，32岁，第二胎，妊娠34周出现皮肤瘙痒、巩膜发黄两周，无其他不适，血压16/12kPa，以往有同样发作史，产后黄疸自行消退；化验SG-PT140单位。若要明确是否为妊娠期肝内胆汁瘀积综合征，下列检查中应首选何项

A．血清总胆红素＋1分钟胆红素

B．血清胆固醇

C．血清胆酸

D．尿胆素

E．麝香草酚浊度试验
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单项选择题

Comparisons were drawn between the development of television in the 20th century and the diffusion of printing in the 15th and 16th centuries. Yet much had happened (91) . As was discussed before, it was not (92) the 19th century that the newspaper became the dominant pree-leetronie (93) , following in the wake of the pamphlet and the book and in the (94) of the periodical. It was during the same time that the communications revolution (95) up, beginning with transport, the railway, and leading (96) through the telegraph, the telephone, radio, and motion pictures (97) the 20th-eentury world of the motor ear and the airplane. Not everyone sees that process in (98) . It is important to do so.
It is generally recognized, (99) , that the introduction of the computer in the early 20th century, (100) by the invention of the integrated circuit during the 1960s, radically changed the process, (101) its impact on the media was not immediately (102) . As time went by, computers became smaller and more powerful, and they became "personal" too, as well as (103) , with display becoming sharper and storage (104) increasing. They were thought of, like people, (105) generations, with the distance between generations much (106)
It was within the computer age that the term" information society" began to be widely used to describe the (107) within which we now live. The communications revolution has (108) both work and leisure and how we think and feel both about place and time, but there have been (109) views about its economic, political, social and cultural implications. "Benefits" have been weighed (110) "harmful" outcomes. And generalizations have proved difficult.

A．ability

B．capability

C．capacity

D．faculty
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