“People were dying and we didn’t know why,” Cornman told me. “We didn’t understand the physics of why the planes were crashing.” The deadly gusts were thought to be blowing in from the ocean or from thunderstorms outside the airports. But the danger turned out to be right above them. In the late seventies, researchers at NCAR and the University of Chicago discovered that the crashes were caused by microbursts—sudden, violent downdrafts. In a microburst, a storm cloud dumps cool air and rain straight down, like water from a broken awning. The air spreads horizontally after it lands, so the pilot thinks he’s flying into a headwind at first. He lifts the plane’s nose slightly and decreases the engines’ thrust. Then the downdraft hits, followed by a vicious tailwind, sending the aircraft to the ground.
蔗糖溶液作为一种易获取、价格低的甜味液体,几十年来已在新生儿临床实践中被用于针刺前的镇痛处理,即在操作前数分钟滴入口腔以起到安抚与止痛作用,但针对特定操作(如静脉采血)的证据一直相对有限,临床应用也存在明显不一致。本次考科蓝团队对相关研究进行系统梳理,试图为这一做法提供更坚实的科学依据,并推动在新生儿病房中形成更加统一的标准化流程。
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