在相同管电压及照射野下,散射线含有率随被照体厚度的增加而大幅度增加。在20cm×20

题型:单项选择题 A3/A4型题

问题:

在相同管电压及照射野下,散射线含有率随被照体厚度的增加而大幅度增加。在20cm×20cm照射野,体模15cm厚度的散射线比体模5cm厚度时增加了一倍。射线含有率随管电压的升高而加大。但在(80~90)kV以上时,散射线含有率趋向平稳。当照射野增大时,散射线含有率大幅度上升。 关于散射线,叙述错误的是()

A.随管电压增大而加大

B.与被照体厚度有关

C.照射野大,散射线多

D.主要来源于康普顿效应

E.对照片密度对比度无影响

考点:医技考试放射技士专业知识2016年放射医学技术士专业知识考前冲刺五
题型:单项选择题 A3/A4型题

目前我们所使用的能源中,不可再生能源的是(  )

A.太阳能

B.水能

C.风能

D.化石能源

题型:单项选择题 A3/A4型题

患者女,47岁,因“反复头痛、呕吐3d”入院。额部痛,用力、咳嗽、弯腰时加重;呕吐呈喷射性。眼底检查:视盘隆起、充血,边缘模糊不清,中央凹陷消失,静脉怒张。

下列检查中首选()。

A.颅脑MRI

B.颅脑CT

C.颅脑X线片

D.腰椎穿刺

E.脑血管造影

题型:单项选择题 A3/A4型题

回答有关生物学问题:

(1)种庄稼要施肥,种草养花需要施肥.在农业生产中施肥时应当注意哪些问题?

______.

(2)春夏时节,有些植物的花并不结果,如黄瓜、南瓜等的花多半都不会结果.请解释这种现象______.

(3)在热带雨林中,有些树木茎干上往往许多毛茸茸的根,这些根暴露在空气中,叫做气生根.这种根的作用是______.

(4)绿色植物光合作用在维持碳---氧平衡方面起重要作用.在我国北方到了冬季许多树的叶子都掉光了,光合作用能力大大降低.但生活在北方的人们没有感觉到缺氧,请解释.

______.

(5)农民把准备移栽的植物幼苗总是带一个土坨,且剪掉部分叶片,这样做的目的是______.

题型:单项选择题 A3/A4型题

根据我国《行政复议法》的规定,在城市规划实施管理中,当事人对城市规划行政主管部门的某些行政行为提出申请复议的,行政复议机关应当在自受理申请之日起的()做出复议决定。

A.十五天内

B.三十天内

C.四十五天内

D.六十天内

题型:单项选择题 A3/A4型题

Many things make people think artists are weird—the odd hours, the nonconformity, the clove cigarettes. However, the weirdest may be this: artists’ only jobs are to explore emotions, and yet they choose to focus on the ones that feel lousy. This wasn’t always so. The earliest forms of art, like painting and music, are those best suited for expressing joy. But somewhere in the 19th century, more artists began seeing happiness as insipid, phony or, worst of all, boring. In the 20th century, classical music became more atonal, visual art more unsettling.

Sure, there have been exceptions, but it would not be a stretch to say that for the past century or so, serious art has been at war with happiness. In 1824, Beethoven completed his " Ode to Joy " . In 1962, novelist Anthony Burgess used it in A Clockwork Orange as the favorite music of his ultra-violent antihero.

You could argue that art became more skeptical of happiness because modem times have seen such misery. But the reason may actually be just the opposite: there is too much happiness in the world today.

In the West, before mass communication and literacy, the most powerful mass medium was the church, which reminded worshippers that their souls were in peril and that they would someday be meat for worms. Today the messages that the average Westerner is bombarded with are not religious but commercial, and relentlessly happy. Since these messages have an agenda—to pry our wallets from our pockets—they make the very idea of happiness seem bogus. " Celebrate! " commanded the ads for the arthritis drug Celebrex, before we found out it could increase the risk of heart attack.

What we forget—what our economy depends on us forgetting—is that happiness is more than pleasure without pain. The things that bring the greatest joy carry the greatest potential for loss and disappointment. Today, surrounded by promises of easy happiness, we need someone to tell us that it is OK not to be happy, that sadness makes happiness deeper. As the wine connoisseur movie Sideways tells us, it is the kiss of decay and mortality that makes grape juice into Pinot Noir. We need art to tell us, as religion once did, that you will die, that everything ends, and that happiness comes not in denying this but in living with it. It’s a message even more bitter than a clove cigarette, yet, somehow, is a breath of fresh air.

How could the economy depend on our forgetting things()

A. The economy would no/be boosted if everybody was satisfied

B. There are many new products designed for the forgetful

C. We pay heavily for forgetting things easily

D. People will spend more money if we believe in easy happiness

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