搜题请搜索小程序“爱下问搜题”
问题 单项选择题

女，29岁，肥胖、头痛伴痛经1年。查体：BP180/110mmHg，向心性肥胖，满月脸，皮肤薄，有痤疮，腹壁有宽大紫纹，下肢胫前可凹性水肿。为明确库欣综合征，拟检查（）

A.血浆皮质醇

B.尿游离皮质醇

C.血皮质醇昼夜节律

D.小剂量地塞米松抑制试验

E.大剂量地塞米松抑制试验

答案

参考答案：D

解析：库欣综合征患者血浆皮质醇水平增高且昼夜节律消失，小剂量地塞米松抑制试验未过夜地塞米松抑制试验，增高的皮质醇不被抑制是库欣综合征必需的确诊试验。

单项选择题 B1型题

老视（）。

A.当眼调节静止时，平行光线经眼的屈光系统后聚焦在视网膜上

B.当眼调节静止时，平行光线经眼的屈光系统后聚焦在视网膜前

C.当眼调节静止时，平行光线经眼的屈光系统后聚焦在视网膜后

D.眼球在不同子午线上屈光力不同，形成两条焦线

E.眼的功能调节力下降
查看答案
填空题

The central problem of economics is to satisfy the people’s and nation’s wants. The problem we are faced with is that our (1) , here identified as money, are (2) . The only way we can resolve our (3) is to make choices. After looking at our resources, we must examine our list of (4) and identify the things we need (5) , those we can postpone, and (6) we cannot afford. As individuals, we face the central problem involved in economics — deciding just how to allocate our limited resources to provide ourselves with the greatest (7) of our wants.
Nations face the same problem. As a country’s population (8) , the need for more goods and services grows (9) . Resources necessary to production may increase, but there are (10) enough resources to satisfy the total desires of a (11) . Whether the budget meeting is taking place in the family living-room, in the conference room of the corporation (12) of directors, or in the chamber of the House of Representatives in Washington, the basic problem still exists. We need to find (13) of allocating limited resources in order to satisfy unlimited wants.
A short time ago, economists divided goods into two categories, free and economic. The former, like air and water, were in (14) abundance that economists had no concern about (15) of scarcity and what to do about it. Today many of these "free goods" are in (16) very expensive to use. Pollution has made clean air and water expensive for producers who have to filter their waste products, for consumers who ultimately pay for the producers’ extra costs, and (17) tax-payers who pay for the government’s involvement in cleaning the environment.
In the 1990s, almost all goods are (18) . Only by effort and money can they be (19) in the form people wish.
Meeting the needs of people and the demands from resources available leads to the basic activity of production. In trying to (20) unlimited wants from limited economic goods, production leads to new problems in economics.
查看答案