下列哪些细胞间相互作用受MHC－Ⅱ分子限制（） A.NK细胞杀伤肿瘤细胞 B.APC

短文填空，在短文的空格内填入适当的词，使其内容通顺，每空格限填一词，词首字母已给。

    Last Sunday the Browns went to the park. They got home very late. Father opened the front door

and they both went into the house. It was very d  1   so Mother turned on the light. On the way to their

bedroom, Mother said, "John, l   2   ! I can hear someone in the bedroom.

    They stood quietly outside the bedroom door. They could hear some v   3   in the room.

    "You’re right," Father said. "There are two men in it. They are talking."Then he shouted, "Who is

there?" But n  4   answered. Father opened the door quickly and turned on the light. The room was

e   5  . Then Father found something and laughed. The radio was still on! "I f   6   to turn it off this

morning,"Father said. Then he turned it off.

答案：1. d________  2.1________  3. v________

            4. n________  5. e________  6. f________

阅读短文，根据其内容回答问题。

Have you heard the expression “You are what you eat”? Well, do you like who you are? If not, break some bad eating habits and feel better about yourself.

Bad habit 1:

Many people often eat packaged ( =" in" small bags) foods at their work places, such as frozen dumplings, rice rolls and instant noodles (方便面), which have lots of fat and calories (热量).

The solution (解答): Read the instructions to find the healthiest foods that are low in salt and high in fiber (纤维). Also check to make sure they have ingredients (混合物) such as vegetables and grains (粮食). When possible, use packaged foods as part of a “home-cooked” meal. For example, frozen dumplings with fresh vegetables are better than dumplings alone.

Bad habit 2:

People without breakfast don’t have enough energy they need to get through the morning. Eating breakfast improves your attention, memory and feelings.

The solution: Always keep a kind of quick foods like yogurt (酸奶). Or have a standing order at a breakfast place.

Bad habit 3:

It takes your body at least 20 minutes to “tell” your brain that you are full, so fast eaters usually eat more than people who eat slowly.

The solution: Try to slow down. Try eating at least some of your meals without TV, hand phones or computers. Use a plate or bowl when you eat.

Bad habit 4:

Healthy snacks (小吃) between meals are fine. But when you snack instead of having real meals, you will not eat your meals regularly. And snack foods such as chips and sweets aren’t very healthy. That makes it easy to overeat.

The solution: To get more energy, allow yourself two healthy snacks a day. Choose snacks that will make you feel full. Try fruit, yogurt or nuts.

As we all know, bad habits can be broken. Take the first step toward a healthier eating habit — start following these tips today! 

小题1:Is the passage about eating habits?     

小题2:What are the healthiest packaged foods?   

小题3:How long does it take your body to tell your brain that you are full? 

小题4:How can you eat snacks healthily? 

小题5:What are the bad eating habits mentioned in the passage?

体积为10dm³，密度为0.4×10³kg/m³的木块，当它漂浮在水面时，它所受到的浮力等于（　　）

A．4 N

B．10 N

C．39.2 N

D．98 N

通道保护倒换和复用段保护倒换的时间均应该小于（）。

A.10ms

B.50ms

C.5ms

D.20ms

如行T管造影无异常发现，T管应如何处置

A．即刻拔除
B．开放T管引流24小时拔除
C．开放T管引流24小时，试夹管2～3天，仍无症状才可拔管
D．开放T管引流1周，试夹管1周，无症状拔管
E．保留T管6周以上