问题 单项选择题

动脉法数字减影血管造影不具有的特点是()

A.密度分辨率高,2%~3%的碘浓度即可使血管显影

B.减去了与靶血管重叠的其他组织和血管影像

C.弥补了静脉数字减影空间分辨率低的缺点

D.使用各种图像处理技术,可提供较多的血管生理病理信息,方便诊断和治疗

E.可避免呼吸、吞咽、肠胃蠕动、心血管搏动的影响

答案

参考答案:E

选择题
单项选择题

The first and most important agents of socialization are the people who care for infants. In the earliest months, messages from nurturers constitute the child’s basic understanding of the world around it. This is the infant’s first introduction to the language that shapes perception and elicits emotion.
Another powerful source of information and socialization is the friendship of peers. Peers are equals that one can deal with on the same level as oneself, whereas parents are superiors. The heavy emotional overlay of family relationships makes some kinds of learning difficult.
Much formal socialization is placed in the hands of professionals. Teachers from kindergarten on are specifically designated agents of socialization. Ideally, a teacher is one who has both knowledge and the skills to present it. During the course of teaching their subjects, classroom instructors provide role models and attempt to convey the excitement of learning itself.
In earlier times, parents, friends and teachers would comprise the list of primary childhood socializers. Children’s books, comics and magazines might also have been mentioned as sources of information on norms and role models. Today one must add three powerful indirect or non-personal socialization agents: radio, movies and television. Many people learn about politics, form a vision of well-being, and develop attitudes towards others from what they see on the screen and hear through the speakers.

In this passage, agents of socialization refer to ______.

A.the media

B.individuals

C.all channels

D.organizations