Glossary
H
heart-lung machine
A machine used to take over the functions of the heart and lungs during surgery. It allows a surgeon to carefully stop the heart while the vital organs continue to receive blood and oxygen.
heat exchangers
Devices that transfer heat between two physically separated fluids; generally consists of a cylindrical shell with longitudinal tubes; one fluid flows inside, the other outside. DAC.
heating systems
Assemblies of interrelated equipment designed to provide heat to buildings and other structures.
Helmholtz pendulum
myograph used to measure the velocity of nerve impulses
hepatitis B
Hepatitis B is a virus spread through the contact of bodily fluids. It is one hundred times more infectious than HIV, and can lead to severe liver damage, but there is an effective vaccine available.
herbal medicine
the use of plant or plant extracts for medicinal purposes in order to improve the body's natural functions and restore balance. Herbal medicines are given in many forms (liquids, infusions, tablets, topical preparations, etc.) and form part of an increasing number of complementary medical therapies
hereditary
Usually refers to a disease that is transmitted from parent to offspring.
heresy
An opposite view to the established or commonly held belief of a religion.
hermetic
A completely closed and airtight seal.
hernia
A small amount of an organ or tissue bulging through an abnormal opening in the skin.
high frequency apparatus
used to apply high frequency electric currents to the body for therapeutic reasons
hip bath
A portable bath in which a person sits immersed up to the hips.
histology
The study of the structure of tissues by means of special staining techniques combined with light and electron microscopy.
HIV
Human Immunodeficiency Virus (HIV) is a virus that weakens vital cells in the immune system, and leads to AIDS. There are two strands: HIV-1, which leads to immunity suppression; and HIV-2, which is not as potent and is only common in West Africa. HIV is spread through direct contact with bodily fluids.
HIV test
HIV tests are used to detect the presence of the human immunodeficiency virus in serum, saliva, or urine. There usually a window time of 22 days (average) between infection and the time that the test can detect infection. There are a wide variety of types of test.
Hodgkin's disease
A human cancerous disease of lymph tissue that appears to originate in a particular lymph node and later spreads through the lymphatic system, the network of capillary vessels in the human body. Symptoms include swelling of the lymph nodes, weight loss and fever. It occurs mostly in individuals between the ages of 15 and 35 and can be successfully treated. Lymph nodes are organs found throughout the body. They contain white blood cells and help the immune system to function correctly.
holism
The theory that parts of the body cannot be explained without reference to the whole body.
hormone
A substance produced in one part of the body which passes into the bloodstream and is then carried to other (distant) organs or tissues, where it acts to modify their structure or function
horn
A hard, projecting, and usually pointed organ, growing upon the heads of certain animals, especially. Of the ruminants, as cattle, goats, and the like. The hollow horns of the Ox family consist externally of true horn, and are never shed.
horn cup
cup drinking vessel made of animal horn