问题 多项选择题

关于钾的代谢和异常,下列哪几项是正确的().

A.无论是细胞内还是细胞外,钾都是最主要的电解质

B.低钾血症时,ECG可出现T波倒置,ST段降低,Q-T间期延长和出现U波

C.静脉补钾时,输液中钾浓度应低于40mmol/L,输钾速度应小于20mmol/h

D.5%碳酸氢钠溶液可用来治疗高钾血症

E.诊断低钾血症时,ECG的变化是最主要的诊断依据

答案

参考答案:B, C, D

解析:钾是细胞内(而不是细胞外)最主要的电解质。当低钾血症达一定程度时,ECG可出现T波倒置、ST段降低,Q-T间期延.长和出现U波等典型的变化。补钾过快时,由于血清钾浓度可能短期内增高很多,有引起心脏停搏的危险,因此静脉补钾有浓度和速度的限制,一般钾浓度应低于40mmol/h,输钾量应小于20mmol/L。诊断低钾主要依靠病史和临床表现,ECG是辅助性诊断措施。高钾血症时应用5%碳酸氢钠溶液,利用其高渗性使血容量增加,从而使血钾稀释;利用其碱性促使H+-K+交换,K+移入细胞内;输入的Na+可使肾远曲小管的Na+-K+交换增加,使K+从尿中排出增加。血钾测定是低钾血症的主要诊断依据,ECG变化可作参考。

填空题
阅读理解

阅读理解。

     Question:What is more astonishing than a 60-ton whale on a

flatbed truck being driven down the street?

     Answer:A 60-ton whale on a flatbed truck exploding and rai-

ning blubber( fat of whales) all over the sidewalk.

    That's what happened in Taiwan recently,when a dead sperm

whale being shipped to the Halobios Research Centre for an autopsy

(尸体解剖) developed an extremely bad case of gas and blew up

before it reached its destination.

     The whale was found alive on a Taiwan beach last weekend,

and died shortly after it was discovered. Since the 56-foot whale was

the largest whale ever beached on Taiwan's shores,scientists wanted

to study it and perform an autopsy for educational purpose.

      Obviously,too much time passed between when the animal died

and the time it was set to be moved to the autopsy location,because

it had already started to go bad. When things rot,they give off gases

as a by-product. In the whale's case,the gases were trapped in its

belly. The pressure inside the rotting creature grew so much that it

popped like an over-filled balloon. Unfortunately,it was on a truck in

the middle of the city of Taiwan at the time ;cars and shops lining the

street were covered with whale bits and juices,much to their owners'

discouragement.

      According to news reports,traffic was tied up for hours while of

ficials tried to clean up the streets.

     Newspaper editors worldwide were probably smiling to them-

selves,since they had a ready-made headline; several reports about

the incident were titled " There  She  Blows ! " after the famous line

from the book Moby Dick.

1. The purpose of the question at the beginning of this news report  is to ___.

A. explain the reason

B. sell newspapers

C. attract readers

D. give an immediate answer

2. The whale's explosion was the result of___.     

A. pressure from gases building up in the creature as it began to rot

B. the long transport of the creature from the beach to the centre

C. the extremely busy traffic in the streets it passed by

D. the quick process of rotting of the animal

3. What is the correct order of the incidents?

        a. The whale was set to a flatbed truck.

        b. The whale was discovered.

        c. The whale exploded.

        d. The whale died.   

A. b;c;a;d                        

B. d;c;b;a

C. b;d;a;c                        

D. d;b;a;c

4. What do we know from the last paragraph?

A. Some newspaper editors were laughed at.

B. Moby Dick is the name of a woman writer.

C. All the newspapers reported the story under the same title.

D. The title" There She Blows ! " is taken from the book MobyDick.