构成红细胞A型主要的两种亚型是()A．A1和A3 B．A1和A2 C．Ax和Am D

如图所示，有两个不计质量的活塞M、N将两部分理想气体封闭在绝热气缸内，温度均是27⁰C．M活塞是导热的，N活塞是绝热的，均可沿气缸无摩擦地滑动，已知活塞的横截面积均为S=2cm²，初始时M活塞相对于底部的高度为Ｈ=27cm，N活塞相对于底部的高度为h=18cm．现将一质量为m=400g的小物体放在M活塞的上表面上，活塞下降．已知大气压强为p₀=1.0×10⁵Pa,

①求下部分气体的压强多大；

②现通过加热丝对下部分气体进行缓慢加热，使下部分气体的温度变为127⁰C，求稳定后活塞M、N距离底部的高度．

在我国，慢性二尖瓣关闭不全的最常见病因是

A．风湿性心脏病

B．结缔组织病

C．感染性心内膜炎

D．二尖瓣黏液样变性

E．二尖瓣先天异常

下列不属于13%低税率范围的是( )。

A．面皮
B．电子光盘
C．林苗栽植机械
D．农机备件

签约电话银行的对公客户使用电话银行可以办理（）

A.行内转账

B.转单位定期存款

C.余额查询

D.历史交易查询

Attempts to understand the relationship between social behavior and health have their origin in history. Dubos (1969) suggested that primitive humans were closer to the animals (1) they, too, relied’upon their instincts to stay healthy. Yet some primitive humans (2) a cause and effect relationship between doing certain things and alleviating (3) of a disease or (4) the condition of a wound. (5) there was so much that primitive humans did not (6) the functioning of the body, magic became an integral component ofthe beliefs about the causes and cures of heath (7) Therefore it is not (8) that early humans thought that illness was caused (9) evil spirit. Primitive medicines made from vegetables or animals were invariably used in combination with some form of ritual to (10) harmful spirit from a diseased body.

One of the. earliest (11) in the Western world to formulate principles of health care based upon rational thought and (12) of supernatural phenomena is found in the work of the Greek physician Hippocrates. The writing (13) to him has provided a number of principles underiying modern medical practice. One of his most famous (14) , the Hippocratic Oath, is the foundation of contemporary medical ethics.

Hippocrates also argued that medical knowledge should be derived from a (15) of the natural science and the logic of cause and effect relationships. In this (16) thesis, On Air, Water, and Places, Hippocrates pointed out that human well-being is (17) by the totality of environmental (18) : living habits or lifestyle, climate, geography of the land, and the quality of air, and food. (19) enough, concerns about our health and the quality of air, water, and places are (20) very much written in twentieth century.

4（）

A.arranging

B.adjusting

C.developing

D.improving