均相酶免疫测定主要用于（）。 A.细菌抗原测定 B.药物和小分子物质测定 C.病毒抗

Have you had a headache during a test Have you ever been so worried about something that you have a headache or even can’t sleep at night If so, then you know what stress is. Stress is what you feel when you are worried about something. This worry in your mind can make your body feel bad. You may feel angry, sad, scared, or afraid—all of which can give you a stomachache or a headache.
However, there are different kinds of stress. Some kinds of stress are good and others are bad. Good stress might happen when you’re called to answer questions in class or when you have to give a speech. This kind of stress can help you to get things better done. For example, you may do a better job on your test if the stress pushes you to prepare better before the test.
On the other hand, bad stress can happen if stress lasts too long. You may not feel well if your parents are fighting, if a family member is sick, if you’re having problems at school, or if anything else makes you unhappy every day. That kind of stress isn’t going to help you. And it can actually make you sick.
The best way to fight stress is to have a balanced life. Make sure you keep your SELF in mind: Sleep, Exercise, Leisure(休闲), and Food. If you get enough sleep and eat properly, and if you exercise and leave time for fun, you’ll probably feel less stressed.

操作系统的功能是 (4) 。

A．把源程序转换为目标代码
B．管理计算机系统中的软、硬件资源
C．负责存取数据库中的各种数据
D．负责文字格式编排和数据计算

系统性红斑狼疮患者可出现的自身抗体有（）

A.RF

B.抗SSA抗体

C.抗SSB抗体

D.抗RNP抗体

E.抗中性粒细胞胞浆抗体

钟表式千分表测杆轴线与被测工件表面必须______，否则会产生测量误差。

A．水平

B．垂直

C．倾斜

主人亲自驾车时，上座是（），专职司机开单位车，（）是上座。