问题 问答题 简答题

白假丝酵母菌的微生物学检验方法有哪些?

答案

参考答案:

(1)直接检查:①直接显微镜检查:取标本直接涂片,革兰氏染色后镜检,见到革兰阳性(着色不均匀)、圆形或卵圆形菌体或孢子及假菌丝,可确认为假丝酵母菌感染。②抗原检测:取病人血清作ELISA、免疫印迹法等检测自假丝酵母菌抗原。③核酸检测:用PCR法将白假丝酵母菌DNA分子扩增后以分子探针检测,具有较好的敏感性和特异性。

(2)分离培养与鉴定:将标本接种在沙保弱培养基上,25℃或37℃培养1~4d后,培养基表面可出现奶油色类酵母型菌落。镜检可见假菌丝和芽生孢子。

(3)其他方法:①芽管形成试验:将待测菌株接种于0.2~0.5ml人或动物血清中,37℃孵育1.5~4小时,显微镜下观察有芽管形成。白假丝酵母菌可形成芽管,但并非所有的白假丝酵母菌都形成芽管,其他假丝酵母菌一般不形成芽管。②厚膜孢子形成试验:将假丝酵母菌接种于玉米粉培养基25℃孵育1~2d后,仅白假丝酵母菌在菌丝顶端、侧缘或中间形成厚膜孢子。③糖同化或发酵试验:不同的假丝酵母菌对糖类的发酵和同化能力是不同的。常用葡萄糖、麦芽糖、蔗糖、乳糖进行发酵试验,用葡萄糖、麦芽糖、蔗糖、乳糖、半乳糖进行同化试验。④现在临床用商品化的产色培养基可快速鉴定白假丝酵母菌和其他假丝酵母菌。⑤动物试验:将假丝酵母菌悬液注射1ml于家兔耳静脉或注射0.2ml于小白鼠尾静脉,观察5~7d,注意动物是否死亡。剖检时如发现脏器有多种小脓肿,即为白假丝酵母菌感染,其他假丝酵母菌对动物无致病性。

阅读理解

In high school I joined the girl athletic club. At our first track meet, I entered for the long jump, but was made an alternate(替补)for the 50 yard dash. I didn’t like it, since I was better at long distance, but they assured me I would never have to run; they just ran out of alternate.

As I walked up to the start line, I saw my Dad on the sidelines. He was watching. Position, ready, set and off went the starting gun. Believe it or not, I closed my eyes and ran like I’d never run before.

I knew I didn’t have a chance of winning. But I started to hear cheering and thought for a minute, was it possible? I opened my eyes and to my disappointment, everyone else was crossing the finish line, inches away from each other and I was only half the distance.

That moment felt like days. I felt so stupid. I just wanted to melt into the ground and disappeared. Worse than that, my Dad was watching and then I felt ashamed. I kept running hard as I could, crying all the way towards the finish line. It seemed no one noticed me as I crossed the finish line. I saw my Dad standing there looking at me. I was ashamed to look at him. He walked over to me and said, “I’m so proud of you.” I was surprised, “For what? Everyone else finished before I even got halfway. I looked like a fool.” “Because you didn’t give up, not even when you realized what had happened. You gave it your all and finished.” I laughed and cried at the same time.

I find I can face what seems impossible, even alone and afraid, and, that winning does not always come in as you expect. I give my best effort to all I do, win or lose. I don’t give up in the middle of anything.

小题1:The author meant to compete in        .

A.the 50 yard dash

B.the long jump

C.the long-distance run

D.the high jump小题2:When the author heard cheering, she thought        .

A.she had the chance to win the game

B.she left others inches away halfway

C.other competitors were encouraging her

D.somebody had won the game小题3:What happened after the author crossed the finish line?

A.She cried at the sight of her father.

B.Everyone cheered her for her success.

C.Her farther came up and comforted her.

D.She felt ashamed to meet her classmates.小题4:What lesson can we learn form the author’s experience?

A.What seems impossible always becomes possible.

B.Don’t lose heart halfway whatever you do.

C.Success will come as long as you expect it.

D.Try to do everything until you win in the end.

单项选择题