Files stored in the UPD format are more commonly known as program update information files. These .upd files are text documents, and its content can be viewed by any text editing or word processing application. Users of Microsoft Windows-based systems can use the Microsoft Notepad application to open and edit these .upd text documents.
Croup (acute laryngotracheobronchitis) on X-ray with steeple sign. Croup, also called acute laryngotracheobronchitis is caused by viral infection of the upper airway usually parainfluenza virus or respiratory syncytial virus (RSV).
National Health System U.K.: Supraventricular tachycardia (SVT) -- Causes. Mount Sinai Hospital: Paroxysmal Supraventricular Tachycardia. American Heart Association: Tachycardia/Fast Heart Rate. Uptodate.com: Epidemiology of and risk factors for atrial fibrillation, Arrhythmias in COPD, Arrhythmias following cardiac transplantation.