实体完整性规则是指关系的主键值不能为______。
参考答案:空值(或Null,或空)
阅读理解。
单词:abroad国外;sailor海员
1. lt was about 42 million Chinese people that went abroad in _____.
A. 2005
B. 2010
C. 2020
2. The number of in 2005 is _____ less than that in 2020.
A. 32 million
B. 69 million
C. 68 million
3. The number of _____ was the largest of all in 2010.
A. sailors
B. Chinese living abroad
C. students
4. Of the three, the number of the _____ going abroad is the smallest.
B. workers
C. Students
5. Which of the following is TRUE from the information above?
A. The number of Chinese living abroad is the largest.
B. The number of students is larger than that of workers.
C. The number of the Chinese workers in foreign countries is larger than that of sailors and others in 2010.
某化工厂男工,36岁。因厂内氯气缓冲罐爆炸,吸入氯气后频咳、流泪、胸闷、呼吸困难入院。体温37℃,脉搏102次/分,呼吸32次/分。体检:眼结膜充血,口唇发绀,咽红肿,咯白色血丝痰。两肺布满干性啰音,两肺底可闻及水泡音。实验室检查:末梢血白细胞数20×109/L,嗜中性粒细胞占84%。X线胸片示两肺中、下野有絮状阴影,边缘不清。
本病的诊断为()
A.急性支气管炎
B.急性化学性发绀
C.急性氯气中毒
D.急性肺水肿
E.亚急性氯气中毒