引起婴儿期佝偻病的主要原因是-我要搜题网

[单项选择]The United Nations, an accepted authority on population levels and trends, estimates that the world population reached 5.3 billion in 1990, and is increasing annually by more than 90 million persons. The rate of increase, 1.7 percent per year, has fallen below the peak rate of 2 percent per year attained by 1970. However, absolute yearly increments are not expected to start declining until after the year 2000.
Estimates of world population before 1900 are based on fragmentary (不全的；不完整的) data, but scholars agree that average population growth approached approximately 0.002 percent per year. Growth was delayed and influenced by climate, food supply, disease, and war.
Starting in the 17th century, great advances in scientific knowledge, agriculture, industry, medicine, and social organization made possible substantial increases in population. Inanimate (无生命的) energy gradually replaced human and animal labor. People slowly acquired the knowledge and means to control disease. All
A. Life expectancy at birth in most developing countries increased over 61.
B. Birth rate will be very high.
C. Death rate will be very low.
D. Life expectancy at birth in most developed countries increased over 61.

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[多选题]司钻上提方钻杆过程中,应观察( ),防止意外情况发生。
A.指重表;
B.悬吊系统运行情况;
C.遇卡情况;
D.井漏情况。

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[单项选择]《素问·脉要精微论》认为脉应“中权”的季节是（）。
A. 春
B. 夏
C. 秋
D. 冬
E. 长春

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[单项选择]男性，19岁。被汽车撞伤左上腹5小时，伤后逐渐出现全腹疼痛。查体：血压95/60mmHg，神志清楚，左上腹压痛、反跳痛，移动性浊音（±），腹穿（-），以下处理最不恰当的是（）。
A. 给予哌替啶止痛
B. 继续观察
C. 静脉输液
D. 再次腹腔穿刺
E. B超

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[简答题]简述桥面防水层常见的病害及处置措施？

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[判断题]客车标记速度分为100km/h、120km/h、140km/h三个等级。
A.正确
B.错误

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[单项选择]

One day while a girl was walking in the woods she found two starving songbirds. She took them home and put them in a small (31) . She cared for them and felt great love for them.
Once the (32) and stronger of the two birds flew from the cage. Therefore, (33) he flew close, she grasped him (34) . She felt glad, but suddenly she felt the bird go limp. She opened her hand and (35) in horror at the dead bird.
She noticed the other bird moving back and forth on the edge of the cage. She could feel his great need for (36) . She lifted him from the cage and (37) him softly into the air. The bird circled once, twice, three times.
The girl watched delightedly at the bird’ s enjoyment. Her heart was no longer (38) with her loss. Suddenly the bird flew closer and (39) softly on her shoulder. It sang the sweetest melody that she had ever heard.
The fastest way to (40) love is to hold o
A. weaker
B. taller
C. larger
D. shorter