Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «H»:
Hobbit: Nickname for the Flores man (Homo floresiensis). Derived from the fictional race from J. R. R. Tolkien's Middle-earth universe which first appears in the book The Hobbit....
Hodgkin disease: A type of lymphoma, a cancer that develops in the lymph system, part of the body's immune system. Because there is lymph tissue in many parts of the body, Hodgkin disease can start in almost any part of the body. The cancer can spread to almost any organ or tissue in the body, inclu...
Hodgkin, Dorothy: British crystallographer and Nobel Prize winner (1910-1994).
Dorothy Crowfoot, as she was born, was educated at Somerville College, Oxford. After a brief period as a postgraduate student at Cambridge University, she returned to Oxford in 1934 and spent her entire academic career t...
Hogwarts headache: A generalized headache from spending many hours reading an unusually long volume such as one of J.K. Rowling's Harry Potter books. The pain resolves one to two days after the patient finishes the book.
The term was coined by Dr. Howard J. Bennett in a Letter to the Editor of The ...
Holandric inheritance: Inheritance of genes on the Y chromosome. Since only males normally have a Y chromosome, Y-linked genes can only be transmitted from father to son.
It has often been said that little is known about specific genes that might be Y-linked (holandric) in their inheritance. This is...
Hole, macular: A hole in the macula, the tiny oval area made up of millions of nerve cells located at the center of the retina responsible for sharp, central vision.
The eye contains a jelly-like substance called the vitreous. Shrinking of the vitreous usually causes the hole. As a person ages, the...
Holmes, Oliver Wendell, Sr.
Holmes, Oliver Wendell, Sr.: (1809-1894). Celebrated American physician and professor of medicine (anatomy and physiology) at Harvard, and of novels, verse, and essays, including medical essays. In one of them, Holmes wrote: "If every drug from the vegetable, animal, and mineral kingdom were to disa...
Holoprosencephaly: A relatively common birth defect of the brain, which often also affects facial features, causing closely spaced eyes, small head size, and sometimes clefts of the lip and roof of the mouth. Not all individuals with holoprosencephaly (HPE) are affected to the same degree, even in f...
Holt-Oram syndrome: A genetic syndrome characterized by the combination of heart disease and malformations of the upper limb. The heart defect is usually an atrial septal defect (ASD) and, less often, a ventricular septal defect (VSD), although other cardiovascular malformations have been reported. ...
Holter monitor: A type of portable heart monitor. The Holter monitor is a small portable electrocardiogram (ECG). The device is worn in a pouch around the neck or waist. It keeps a record of the heart rhythm, typically over a 24-hour period, while the patient keeps a diary recording their activities...
Homeobox gene: A gene containing a short DNA sequence of about 180 base pairs referred to as a homeobox. Homeobox genes encode proteins that bind and regulate the expression of DNA in multicellular organisms. Homeoboxes are present in the genomes of many organisms from fruit flies to humans, and the...
Homeopath: A person who practices homeopathy. ...
Homeopathic: Pertaining to homeopathy....
Homeopathic medicine: See: Homeopathy....
Homeopathy: A system of
therapy based on the concept that disease can be treated with drugs (in minute doses) thought capable of producing the same symptoms in healthy people as the disease itself.
Homeopathy was invented by the German physician Samuel Hahnemann (1755-1843) in the late 18th and ear...