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问题 单项选择题 A1型题

在分子流行病学研究中，暴露标志和效应标志是结合疾病的不同阶段和研究需要确定的；根据研究目的不同，许多情况下，一项生物标志（）

A.作为暴露标志就不能作为效应标志

B.作为效应标志就不能作为暴露标志

C.有时作为效应标志，有时也可作为暴露标志

D.可以同时既是暴露标志又是效应标志

E.只是作为暴露标志

答案

参考答案：C

解析：本题考点为充分理解暴露发病连续带模型的含义。根据暴露发病连续带模型，暴露和效应是相对的。因此很多情况下，一项生物标志在某个研究中可能是效应标志，而在下一级效应标志的影响因素研究中，它有可能作为暴露标志。

单项选择题

In the United States, the first day nursery was opened in 1854. Nurseries were established in various areas during the (91) half of the 19th century; most of (92) were charitable. Both in Europe and in the U. S. , the day-nursery movement received great (93) during the First World War, when (94) of manpower caused the industrial employment of unprecedented numbers of women. In some European countries nurseries were established (95) in munitions (军火)plants, under direct government sponsorship. (96) the number of nurseries in the U.S. also rose (97) , this rise was accomplished without government aid of any kind. During the years following the First World War, (98) , Federal, State, and local governments gradually began to exercise a measure of control (99) the day nurseries by (100) them and by inspecting and regulating the conditions within the nurseries.
The (101) of the Second World War was quickly followed by an increase in the number of day nurseries in almost all countries, as women were (102) called upon to replace men in the factories. On this (103) the U. S. government immediately came to the support of the nursery schools, (104) $6,000,000 in July, 1942, for a nursery school program for the children of working mothers. Many States and local communities (105) this Federal aid. By the end of the war, in August, 1945, more than 100,000 children were being cared (106) in day-care centers receiving Federal (107) Soon afterward, the Federal government (108) cut down its expenditures for this purpose and later (109) them, causing a sharp drop in the number of nursery schools in operation. However, the expectation that most employed mothers would leave their (110) at the end of the war was only partly fulfilled.

A．unanimously

B．sharply

C．predominantly

D．militantly
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单项选择题

肾上腺素中检查酮体的方法为( )。

A．薄层色谱法
B．红外分光光度法
C．高效液相色谱法
D．目视比色法
E．紫外分光光度法
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