They have already been placed on reduced-volume nasogastric (NG) feeds but continue to have a severe work of breathing with an FiO2 of 40%. You feel they are a candidate for high-flow nasal cannula support. The senior nurse asks you if you want to start at 15L flow. You recall being...
郑某，男,50岁。受凉后突起寒战、高热、胸痛伴咳嗽1天。病人既往无慢性呼吸系统疾病及糖尿病病史，吸烟30余年，每天约20支，已戒烟2年，长期酗酒,10年前诊断为慢性肾炎，长期服用糖皮质激素治疗。痰涂片可见革兰染色阴性细菌。临床初步判断为肺炎。
质点做直线运动的v-t图象如图所示，表示质点不是做匀速直线运动的是（ ）