【单选题】下列对胆道感染的概述,不正确的是
B.
包括急性胆囊炎、慢性胆囊炎、急性胆管炎、急性化脓胆管炎
C.
致病菌为金黄色葡萄球菌、溶血性链球菌、肺炎双球菌
D.
易形成结石,阻塞胆总管80%~90%合并感染
E.
重症感染可并发胆囊穿孔、胆道出血、肝脓肿、中毒性休克
【单选题】Which of the following must be true if the short-run average total cost curve is declining?
A.
Marginal cost is less than average total cost.
B.
Marginal cost is less than average variable cost.
C.
Marginal cost is greater than average total cost.
D.
Marginal cost equals average total cost.
【判断题】If the marginal cost of producing the tenth unit of output is $3, and if the average total cost of producing the tenth unit of output is $2, then at ten units of output, average total cost is rising.
【判断题】If the price of a good rises above the minimum average total cost of production, positive economic profits will cause new firms to enter the market, which drives the price back down to the minimum ave...
【单选题】有关医院感染预防和控制的概念错误的是( )
E.
体温计用消毒液浸泡,血压计及听诊器可用熏蒸箱消毒
【单选题】关于医院感染预防与控制概念的叙述错误的是
【单选题】If marginal cost is below average total cost, then average total cost
D.
may rise or fall depending on the size of fixed costs.
【判断题】某市养鱼利用水面 2.2 万公顷,垂钓水面 8000 公顷,垂钓单位面积利润比一般养殖高 5 — 6 倍。这说明休闲农业最重要的功能是生产功能。( )
【判断题】光电二极管工作时一般处于反向工作状态,它的反向电流会随光照强度的增加而减小。
【单选题】有关医院内感染预防与控制的概念,错误的是