问题 单项选择题

下述肝脂肪变性的原因描述中,哪项是错误的(注:该题的设计不够严谨)

A.化学毒物使脂蛋白合成障碍,导致肝脂肪变性

B.糖尿病时,脂肪酸入肝过多,导致肝脂肪变性

C.缺氧时可导致肝脂肪变性

D.食入脂肪过多导致肝脂肪变性

E.白喉杆菌外毒素影响脂肪酸代谢导致肝脂肪变性

答案

参考答案:D

解析: 单纯的食入脂肪过多不会导致肝脂肪变性(该题的设计不够严谨)。因为正常的肝脏有能力将进入肝脏的乳糜微粒合成为脂蛋白,并输送到脂库中储存。而任何干扰或破坏肝细胞脂肪代谢的因素均能引起脂肪变性。酒精等化学毒物能使脂蛋白或组成脂蛋白的磷脂、蛋白质合成障碍,脂肪不能运输入血,而在细胞内堆积。缺氧除影响脂蛋白各种成分的合成外,还影响脂肪酸的氧化,减少脂肪细胞内脂肪的消耗,可引起脂肪沉积。糖尿病时对糖的利用障碍,因而脂库动员出现大量脂肪,其中大部分以脂肪酸的形式进入肝脏,导致肝细胞脂肪合成增加,超过其氧化、利用和合成脂蛋白并排泌出细胞的能力。而白喉外毒素能干扰脂肪酸的氧化过程,均能导致肝细胞脂肪变性。

完形填空

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项,选项中有两项为多

余选项。

In times of economic downturn, many people start to look for ways to reduce their household budget and save extra cash. Living a thrifty (节俭的) lifestyle does not have to mean doing nothing.   小题1:   Here are some tips.

Track your spending for at least 2 weeks. You won’t really know how to live a thriftier lifestyle until you know where your money is going. Write down every time you spend money and take a look at it at the end of the month.  小题2:

Search the Internet when you have to buy something. Because of the easy access to information, you can compare prices from more stores in less time.

 小题3: Combining producers’ coupons (优惠券) with store discounts can lead to major savings.

Turn off the lights and other electronics in your home when you are not using them. 小题4:   Leaving electronics on can use a tremendous amount of extra energy, costing you money.

 小题5:  When you do have to go out, look for available deals and discounts. If you are a frequent restaurant diner, consider purchasing a guide book for local restaurants, which will help you save money.

A.Eat at home as often as possible.

B.You probably don’t really need 500 channels.

C.If you really can’t live without it, call the company.

D.Open a window and let in the natural light instead.E. In this way, you will see obvious ways to reduce the small daily expenses.

F. So check your local stores as well as online providers to find the best price.

G. Instead, making small changes will allow you to save money and still enjoy yourself.

判断题