问题 单项选择题 B1型题

测定尿5-羟色胺、醛固酮时尿液所用的防腐剂是()

A.中性甲醛

B.浓盐酸

C.冰乙酸

D.麝香草酚

E.甲苯

答案

参考答案:C

解析:甲苯可在尿液表面形成一层甲苯薄膜,阻止尿液中化学成分与空气接触,达到防腐结果。肾上腺素、儿茶酚胺在酸性环境中较稳定,加酸降低pH,是最好的保存方法。酸性环境中较稳定。

阅读理解

Pat O’Burke was a poor Irishman with a large family, and one morning, waking up very early from cold and hunger, he decided to go shooting in a wood near his cottage. The wood belonged to Lord Northwood, a rich gentleman, Pat had no right to go there, but in it there were swarms of rabbits and flocks of birds that were good to eat, and Pat determined to take the risk. Suddenly he saw the owner, with a group of friends, coming towards him in the wood. There was a look of anger on Lord Northwood's face as he caught sight of the gun in Pat's hands. Pat's heart sank with fear, but he saw there was no hope of escape, so he walked boldly (大胆) up to the group and said to Lord Northwood, “Good morning, sir, and what has brought you out so early this morning?” Lord Northwood, rather surprised, said he and his friends were taking a little exercise to get an appetite(食欲) for their breakfast. Then, looking at Pat with suspicion(怀疑), he said, “but why are you out so early in the morning?” “Well, sir” said Pat, “I just came out to see if I could get a breakfast for my appetite.” The whole crowed burst into laughter at Pat's ready wit(机智,风趣), and with a smile Lord Northwood walked on, leaving Pat to try his luck with the rabbits.

小题1:This is a story about _____.

A.a rich man who owned a big wood

B.a poor Irishman who lived all by himself

C.a clever man who tried to get something to eat

D.an Irish hunter with a large family小题2: There was a look of anger on Lord Northwood's face. Why?

A.He was not expecting Pat at this early hour.

B.He knew Pat was coming for shooting.

C.He didn't like the poor Irishman at all.

D.Pat had not told him he would come.小题3:Why was Lord Northwood surprised?

A.He had not expected such a bold question from Pat.

B.He wondered why Pat didn't run away.

C.Pat wasn't afraid of him.

D.Pat had a gun in his hands.小题4: What made the whole crowd burst into laughter?

A.Pat's funny looks

B.Pat's interesting remarks

C.Pat's quick and humorous response

D.Pat's promise to leave fight away小题5: Guess the meaning of the underlined word “right”.

A.对的

B.右边

C.正好

D.权利

选择题