已知a、b互为相反数，c、d互为倒数，则代数式3（a+b）-cd的值为（ ） A

根据我国食物与营养发展的指导思想，食物与营养发展的重点领域不能放在（）。

A.大豆产业

B.奶类产业

C.酒类产业

D.食品加工业

男性患者，胃溃疡病史7年，近日腹痛规律性消失，3h前突发上腹部剧烈腹痛，深呼吸时疼痛加重，诊断为急性弥漫性腹膜炎，该患者不可能有以下哪种体征

A．腹肌紧张
B．腹部压痛
C．反跳痛
D．肝浊音界扩大
E．腹式呼吸明显减弱

以下决定进入壁垒高度的主要因素不包括（）。

A.产品差异

B.产品的转换成本

C.政府政策

D.现有产品的成本优势

What of the following is true of Lesley a. He was charged of committing fraud and is under a probe led by some officials. b. Some officials cooperated with the prosecutors to force him to plead guilty. c. He was charged of taking bribes as an official. d. Some officials are involved in the corruption scandal that is being investigated with the help of him.

全身麻醉最基本的特征是

A．反射抑制
B．中枢神经系统受抑制
C．疼痛消失
D．肌肉松弛
E．呼吸功能消失