1 Red blood cells (RBCs) are also called erythrocytes. They make up almost half of blood. Red blood cells are filled with hemoglobin. That's a protein that picks up oxygen in the lungs and brings it to cells all around the body.  White blood cells (WBCs) are also called leukocytes.
Pain originating in the stomach or esophagus is often felt in the upper abdomen and can be due to heartburn, gastroesophageal reflux disease (GERD), or hiatal hernia (weakening in the diaphragm that allows the stomach to protrude into the chest). You may also have gastritis (inflammation of the stomach lining) or ulcers.
7 ways to calm your upset stomach. Healthbeat. Maybe you've just eaten, or finished a meal an hour or so ago â and now your stomach just doesn't feel right.. You feel bloated and uncomfortable. Or maybe it's more of a burning sensation. Maybe you feel queasy, or even throw up. You might say you have an upset stomach or indigestion. If there is no known medical cause for your symptoms, your doctor would call it dyspepsia or bad digestion.. Indigestion is real. The medical term for persistent upper abdominal pain or discomfort without an identifiable medical cause is functional dyspepsia.