Sinusitis is an inflammation of the sinuses. It is often caused by bacterial (germ) infection. Sometimes, viruses and fungi (molds) cause it. People with weak immune systems are more likely to develop bacterial or fungal sinus infection. Some people with allergies can have allergic fungal sinus infection. Acute sinus infection lasts three to eight weeks. A sinus infection lasting longer than eight weeks is considered chronic.
Define Upper stage. Upper stage synonyms, Upper stage pronunciation, Upper stage translation, English dictionary definition of Upper stage. n. A rocket composed of two or more propulsion units that fire in succession. Also called step rocket . Noun 1. multistage rocket - a rocket having two or...
An upper gastrointestinal (GI) series (barium swallow), is a radiological test that is used to visualize the structures of the upper digestive system - the esophagus, stomach and duodenum. (If visualization of the remaining parts of the small intestine is necessary, a small bowel follow through can be added to the test.)