Part A
Directions: Read the following four texts. Answer the questions below each text by choosing A, B, C or D . Mark your answers on ANSWER SHEET 1.
Botany, the study of plants, occupies a peculiar position in the history of human knowledge. For many thousands of years it was the one field of awareness about which humans had anything more than the vaguest of insights. It is impossible to know today just what our Stone Age ancestors knew about plants, but from what we can observe of preindustrial societies that still exist, a detailed learning of plants and their properties must be extremely ancient. This is logical. Plants are the basis of the food pyramid for all living things, even for other plants. They have always been enormously important to the welfare of people, not only for food, but also for clothing, weapons, tools, dyes, medicines, shelter, and a great many other purposes. Tribes living today in the jungles of the Amazon recognize literally hundreds of plants and know many properties of each. To them botany, as such, has no name and is probably not even recognized as a special branch of "knowledge" at all.
Unfortunately, the more industrialized we become, the farther away we move from direct contact with plants, and the less distinct our knowledge of botany grows. Yet everyone comes unconsciously on an amazing amount of botanical knowledge, and few people will fail to recognize a rose, an apple, or an orchid. When our Neolithic ancestors, living in the Middle East about 10,000 years ago, discovered that certain grasses could be harvested and their seeds planted for richer yields the next season, the first great step in a new association of plants and humans was taken. Grains were discovered and from them flowed the marvel of agriculture: cultivated crops. From then on, humans would increasingly take their living from the controlled production of a few plants, rather than getting a little here and a little there from many varieties that grew wild—and the accumulated knowledge of tens of thousands of years of experience and intimacy with plants in the wild would begin to fade away.
Which of the following assumptions about early humans is expressed in the passage?
A.They probably had extensive knowledge of plants.
B.They thought there was no need to cultivate crops.
C.They did not enjoy the study of botany.
D.They placed great importance on the ownership of property.
第1題
避免超聲入射角對血流成像影響的方法是
A、高頻超聲
B、減低檢測深度
C、低頻超聲
D、能量多普勒成像
E、高脈沖重復(fù)頻率技術(shù)
第2題
速度型彩色多普勒成像的優(yōu)點是
A、超聲入射角不影響成像
B、二維超聲圖像質(zhì)量不受影響
C、奈奎斯特(Nyquist)極限不影響成像
D、可顯示血流空間分布
E、成像幀頻不受檢測深度的影響
第3題
對速度型彩色多普勒技術(shù)特點,錯誤的是
A、用彩色表示血流方向
B、成像不受超聲入射角影響
C、產(chǎn)生信號混迭
D、彩色的明亮度與流速相關(guān)
E、不能測量峰值速度
第4題
增大脈沖波多普勒檢測血流速度范圍的方法是
A、減小超聲入射角
B、降低超聲頻率
C、增大增益調(diào)節(jié)
D、提高超聲頻率
E、減低發(fā)射超聲脈沖重復(fù)頻率
第5題
彩色多普勒能量圖的技術(shù)特點不包括
A、血流成像不受超聲入射角的影響
B、彩色信號表示血流方向
C、高速血流成像時不出現(xiàn)彩色信號混疊
D、彩色信號的明亮與暗淡不標(biāo)志流速的快慢
E、顯示低流速、低流量的血流
第6題
測量角膜厚度用以下哪種超聲檢測最好
A.M型超聲
B.彩色多普勒血流顯像
C.超聲顯微鏡
D.B型超聲
E.多普勒能量圖
第7題
A.M型超聲
B.頻譜多普勒
C.彩色多普勒
D.組織多普勒
E.斑點追蹤顯像
第8題
A.超聲諧波成像技術(shù)
B.三維超聲成像技術(shù)
C.超聲彈力成像技術(shù)
D.超聲速度向量成像技術(shù)
E.超聲彩色多普勒血流成像技術(shù)
第9題
A.從彩色信號的顏色可判斷是動脈或靜脈
B.血流成像不受超聲入射角的影響
C.高速血流成像時易出現(xiàn)彩色信號折返
D.只能用于顯示極低速的血流
E.血流速度過高時不出現(xiàn)彩色信號折返
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