试述焊接区内氢气的来源？它有什么危害？如何控制？

阅读短文，判断正（T）误（F）。

     A city is a very big place. Sometimes it's a lonely place, too. There are thousands of people in a city, but

some of them don't have any friends. How about you? Do you have a lot of friends? If you don't, make friends

today. If you do, make another friend today. Pick a stranger at your job or school. Walk up to him or her and

say,"Hello. My name' s....What' s your name?" Start with a conversation(谈话). Smile, listen carefully, and

show interest in your new friend' s answers. Ask "Where are you from?" and "Do you like this city?" That' s

a good way to start.

( )1. A city is a very big and noisy and lonely place.                                                        

( )2. Everyone in the city has many friends.                                                                  

( )3. The paragraph tells us not to make friends in a city.                                                   

( )4. When you want to make friends with someone, please say at first, "What's your name?  

           How old are you?"

( )5. It's a good thing to make friends with others.                                                          

与结肠癌和直肠癌有关（）

A.EB病毒

B.人 * * 瘤病毒

C.人嗜FT淋巴细胞病毒

D.甲胎蛋白

E.癌胚抗原

患者，女性，65岁。上腹隐痛伴黏液血便半年。查体：上腹部可触及肿物。钡灌肠：横结肠近脾曲处充盈缺损。

该患者如需手术治疗，手术范围包括（）。

A.全结肠切除

B.病变肠管局部切除

C.横结肠、降结肠及其系膜，大网膜

D.横结肠及其系膜，部分升结肠和降结肠、大网膜

E.升结肠造口并横结肠、降结肠、直肠及其系膜切除

《中华人民共和国药品管理法》规定的药品是指用于（）

A.防病、治病的特殊商品

B.预防、治疗人的疾病的物质

C.预防、诊断人的疾病的物质

D.预防、治疗、诊断人的疾病的物质

E.预防、治疗、诊断人及动物疾病的物质

从所给的四个选项中，选择最合适的一个填入问号处，使之呈现一定的规律性：（）

A.A

B.B

C.C

D.D