乙胺丁醇治疗结核病时联合用药的主要目的是（） A.促进药物进入_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题单项选择题 A1/A2型题

乙胺丁醇治疗结核病时联合用药的主要目的是（）

A.促进药物进入细胞内

B.延长药物半衰期

C.延缓耐药性产生

D.扩大药物抗菌范围

E.减少不良反应

答案

参考答案：C

解析：乙胺丁醇可能通过与二价金属离子结合干扰细菌RNA的合成，另外可能抑制分枝菌酸渗入分枝杆菌细胞壁，使其生长受到抑制。单用可产生抗药性，但较慢，故应与其他抗结核药合用，它们之间无交叉抗药性。

计算题

如图所示，R₁＝10欧的电阻和滑动变阻器R₂串联，A、B接到电压为6伏的电路中。将滑动变阻器的滑片P移到a点，变阻器a点左侧电阻为R_a，R_a＝R₂/3。将量程为0.6安的电流表或量程为3伏的电压表接到电路中C处，电表的指针恰好指示满量程。

（1）接在C处的是________表。

（2）保持原电路不变，如果将C处的电表换成另一块电表，那么此刻电表的示数是多少?

（3）换成另一块电表后，若移动滑片P到某一点，使滑动变阻器消耗的电功率是0.8瓦，通过R₁的电流可能是多少?

完形填空

Yesterday was my stepmother’s birthday. I haven’t been home for a long time, so I wanted to stop by the house to 36 her on this special day. I have been 37
on a low income so I was afraid that I couldn’t afford the long 38 . Gas is so expensive nowadays! 39 , I filled my tank with gas and set off.
I 40 at a shopping mall and found a present. It was the 41 gift and I knew she would love it. 42 when I got to the cashier, my card was 43 !
I didn’t have enough money to 44 the gift!
So I thought about the 45 for a few minutes. I could put it back and get something 46 , but I knew there was 47 else in the store she would have liked as much. So, I transferred some money from my saving account and was able to buy the gift. It took a 48 part of my savings but I wanted her to have something special.
It turned out that she loved the gift and I 49 that even though I had spent almost all my money, my stepmother 50 the best. I was glad I gave her the best I could.
Before I 51 my parents’ house, my dad took me to one side and, with our secret handshake, he gave me some money. I hadn’t 52 anything to him about my financial 53 , but I guessed my dad just knew. When I got to the car, I saw the 54 he gave me was three times what I had spent on the gas and the gift! It shows that doing the right thing always comes with great 55 .