向心球轴承装配,当内圈与轴配合较紧,外圈与壳体较松时,应先将轴承装在()。
A.轴上
B.壳体孔中
C.同时装入
D.随意
参考答案:A
It is known to all that nothing is much precious than time. A famous saying goes, “Time is money”, which shows that time is invaluable. When time is gone, it will never return back. But it is pity that some people didn’t make full use of their time. They spend a lot of time sleep, chatting or playing computer game. They don’t realize that wasting time is actual equal to killing themselves. We always regret not having made great achievements. However, to be successful, they should first form the habit of being on time. Don’t put down what can be done today until tomorrow. Being lazy will eventually lead to failure.
病历摘要:中央型肺癌患者,男性,53岁。咳嗽,咳痰2月余,痰中间或带血丝。患者有吸烟史20余年,每天20支。查体.右下肺呼吸音减弱,可闻及湿啰音。心脏无异常。行胸部平片检查。
3、鉴别诊断有哪些?