Kids Research Express

Geriatrics, specialized branch of medicine that deals with the diseases of older persons and their therapy. The study of the aging process itself is called gerontology . Increased interest in geriatrics is due largely to the greater number of older persons in society, which is in turn a result of social and medical changes that have extended the life expectancy in the United States from an average of 47 years in 1900 to 76.3 years in 2000. The elderly population is expected to increase rapidly over the next 30 years, with the number of persons over 85 growing most rapidly. In 1975 the U.S. Congress established the National Institute on Aging (NIA) to sponsor research on aging and on therapy for the problems of older persons. In 1978 the Institute of Medicine of the National Academy of Sciences issued a report recommending greater integration of knowledge on aging and geriatrics into the curriculum of medical schools. Some physicians have advocated establishing special geriatric care un

Pulmonary Diseases, diseases affecting the lungs. Though the mouth, nose, and throat help filter and clean the air we breathe, the lungs are subject to inhaled pathogens, such as bacteria and viruses, as well as such toxic substances as cigarette smoke or air pollution. For information on: • bacterial and viral diseases affecting the lungs, see Influenza ; Legionnaires' Disease ; Pneumonia ; Tuberculosis • lung problems caused by environmental factors, see Altitude Sickness ; Bronchitis ; Emphysema • pulmonary problems due to allergy or other causes, see Bronchial Asthma ; Croup • congenital pulmonary diseases, see Cystic Fibrosis ; Heart: Congenital Diseases • areas where climate is beneficial to sufferers, see Adirondack Mountains

Hematology, medical specialty concerned with the study of blood and blood-forming tissues. Physicians in this field are known as hematologists. They study, diagnose, and treat blood disorders such as leukemia , anemia , and hemophilia , as well as diseases of the organs that produce blood, including the lymph nodes, bone marrow, and spleen. Hematologists use laboratory-based blood tests to diagnose a variety of disorders. Of particular importance are blood tests that provide information about the cellular components of a patient's blood. The most common test, called a complete blood count (CBC), indicates the number of red blood cells, white blood cells, and platelets in a given unit of blood. Hematologists also examine blood samples under a microscope to identify abnormal blood cells and diagnose blood diseases. In addition to testing for blood diseases, hematologists may also be called on to diagnose other types of disorders, such as hepatitis C, a chronic liver disease that is

Gastroenterology, medical specialty that focuses on the human digestive system and the diseases that affect it. Specialists in the field, called gastroenterologists, study and treat disorders of the esophagus, stomach, small and large intestines, and colon—collectively called the gastrointestinal tract—as well as disorders of the liver, gallbladder, and other organs involved in digestion. Among the most common conditions that gastroenterologists care for are disorders of the stomach , the organ that receives, stores, and partially digests food in the early steps of human digestion. Gastritis, for example, is an inflammation of the stomach lining that often results in abdominal pain, nausea, and vomiting. Gastritis may be caused by the bacterium Helicobacter pylori, viral infections, stress, allergies, and reactions to alcohol, aspirin, or other substances. A gastroenterologist must identify the causative agent in order to treat this inflammation. Gastroenterologists also specialize i

Internal Medicine, nonsurgical medical specialty concerned with diseases of internal organs in adults. Physicians who specialize in the field, known as internists, are skilled in disease prevention and in managing complex disorders of the body. Internists may be either generalists or specialists. General internists typically act as personal physicians, developing long-term relationships with patients. Internists give patients regular physical examinations, offer preventive care, diagnose and treat most nonsurgical illnesses, and refer serious or unusual cases to an appropriate specialist. If a patient complains of persistent stomach problems, for example, a general internist might refer the patient to a gastroenterologist, an internist who specializes in disorders of the digestive system. Within the field of internal medicine, nine subspecialties are recognized: cardiology , the treatment of diseases of the heart and blood vessels; endocrinology , the study of glands and other structur

Coma, in medicine, state of unconsciousness in which a person is unresponsive to external stimuli. In the deepest coma, spontaneous respiration ceases, and a mechanical respirator must be used (see Artificial Respiration ). Coma may last for a few days or, in rare cases, for years, usually progressing after the first month to a persistent vegetative state. Coma in which electrical activity can no longer be detected in the brain is called brain-death syndrome (see Death and Dying ). Coma results from decreased metabolic activity in the brain, which may be caused by cerebral hemorrhage, inflammation of the brain due to meningitis or encephalitis , drug overdose, oxygen deprivation (as in cardiac arrest), or abnormal metabolism. Among the conditions that can cause metabolism abnormalities are diabetic ketoacidosis, in which the blood is too acidic; a high blood level of ammonia, which often follows liver damage caused by alcohol ; or uremia , in which damaged kidneys cannot process the t

Asthma, disorder of the respiratory system in which the passages that enable air to pass into and out of the lungs periodically narrow, causing coughing, wheezing, and shortness of breath. This narrowing is typically temporary and reversible, but in severe attacks, asthma may result in death. Asthma most commonly refers to bronchial asthma, an inflammation of the airways, but the term is also used to refer to cardiac asthma, which develops when fluid builds up in the lungs as a complication of heart failure. This article focuses on bronchial asthma. Asthma attacks occur when the bronchi and bronchioles become inflamed, reducing the space through which air can travel through the lungs. This causes the asthmatic to work harder to move air in and out of the lungs. Asthma attacks usually begin with mild chest pressure and a dry cough. As an attack intensifies, wheezing develops and increases in pitch; breathing becomes difficult; and coughing produces thick, stringy mucus. As the airway