搜题请搜索小程序“爱下问搜题”
问题 问答题 简答题

简述大气污染的定义及分类。

答案

参考答案：

（1）大气污染：指由于人类活动或自然过程使得某些物质进入大气中，呈现出足够的浓度，达到了足够的时间，并因此而危害了人类的舒适、健康和福利或危害了环境的现象。

（2）大气污染可分为：局部地区污染、地区性污染、广域污染、全球性大气污染。

单项选择题

Modern liberal opinion is sensitive to problems of restriction of freedom and abuse of power. (1) , many hold that a man can be injured only by violating his will, but this view is much too (2) . It fails to (3) the great dangers we shall face in the (4) of biomedical technology that stems from an excess of freedom, from the unrestrained (5) of will. In my view, our greatest problems will be voluntary self-degradation, or willing dehumanization, as is the unintended yet often inescapable consequence of sternly and successfully pursuing our humanization (6) .

Certain (7) and perfected medical technologies have already had some dehumanizing consequences. Improved methods of resuscitation have made (8) heroic effort to "save" the severely ill and injured. Yet these efforts are sometimes only partly successful: They may succeed in (9) individuals, but these individuals may have sever brain damage and be capable of only a less-than-human, vegetating (10) . Such patients have been (11) a death with dignity. Families are forced to bear the burden of a (12) "death watch".

(13) the ordinary methods of treating disease and prolonging life have changed the (14) in which men die. Fewer and fewer people die in the familiar surroundings of home or in the (15) of family and friends. This loneliness, (16) , is not confined to the dying patient in the hospital bed. As a group, the elderly are the most alienated members of our society: Not yet (17) the world of the dead, not deemed fit for the world of the living, they are shunted (18) . We have learned how to increase their years, (19) we have not learned how to help them enjoy their days. Yet we continue to bravely and feverishly push back the frontiers (20) death.

9（）

A.supporting

B.rescuing

C.replacing

D.retrieving
查看答案
单项选择题 共用题干题

遗传性疾病的基因诊断不能离开对遗传标记的合理运用。请回答下列问题。

以下不属于STR多态性检测最常用的方法是（）

A.PCR扩增、电泳分离

B.银染或荧光分析等位基因片段大小、分型

C.利用DNA测序仪直接进行序列分析

D.Taqman技术

E.STR复合扩增技术
查看答案