引起肾素—血管紧张素—醛固酮系统激活的主要因素有()
A.肾灌注减低
B.血容量降低
C.利尿剂作用
D.精神紧张,寒冷
E.以上均不对
参考答案:A, B, C, D
George's Appliance Center sells big screen televisions. On a representative model, when the price was reduced from $ 2450 to $ 2275, monthly demand increased from 175 to 211 units. What is the price elasticity of demand()
A. -2.14.
B. -1.69.
C. -2.53.
女,16岁。近10个月来右上腹痛频繁伴黄疸,且逐渐加重,大便呈陶土色,消炎利胆治疗无好转。患儿生后6天曾行先天性胆总管囊肿十二指肠吻合术。
此合并症最公认的原因是().
A.结石
B.胰液逆流
C.胆汁淤积
D.吻合口狭窄
E.肝硬化