跪求1、“Effect of continuous aspiration of subglottic secretions on the prevention of ventilator-associated pneumonia in mechanically ventilated patients: a prospective, randomized, controlled clinical trial”，2、“Continuous aspiration of subglottic secretions in preventing ventilator-associated pneumonia”3、“Successful prevention of ventilator-associated pneumonia in an intensive care setting”，无限感激！！
