Glossary Index by Letter

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Bulging of tissue through an opening in a membrane, muscle or bone. A protrusion of an organ or part through connective tissue or through a wall of the cavity in which it is normally enclosed -- called also rupture. A brain herniation is the displacement of brain...


Composed of varied cell types. Made up of elements or ingredients that are not alike.


The Human Menopausal Gonadotropin Human Menopausal Gonadotropin; derived from the urine of post-menopausal women, hMG not only contains LH but also FSH.


Composed of identical cell types. Of uniform composition or structure.

Hormone (Adj. Hormonal)

A chemical "messenger" which is made and secreted by an endocrine gland and which targets one or more parts of the body, modifying its structure or changing the way it works. Hormones are chemical substances having a specific regulatory effect on the activity of a...

Hormone Replacement Therapy

The name given to a form of treatment in which missing or deficient hormones can be replaced, the body being encouraged to behave normally as if it were making the hormones naturally. Doses are designed to mimic normal blood levels and vary depending on the patient.


A condition marked by an excessive accumulation of fluid resulting in enlarging of the brain cavities and raised pressure within the skull; may also result in enlargement of the skull and wasting of the brain. The abnormal buildup of cerebrospinal fluid in the...


An increased number of smaller dosage treatments of radiation therapy. Radiation therapy that gives smaller doses (fractions) of radiation more often than standard radiation therapy so that the full treatment course can be given with fewer side effects. In...

Hypogonadism (Adj. Hypogonadal)

The inability of the gonads to function normally. Can be due to pituitary dysfunction or else dysfunction of the glands (ovaries and testicles).


Intracranial pressure, harmful when increased. Intracranial pressure monitoring is done using a device placed inside the head which senses the pressure inside the brain cavity and sends data to a recording device. There are three procedures to monitor intracranial...


Produced by the liver, formerly known as somatomedin-C, and is a marker of the amount of GH secreted over time.


Increased intracranial pressure. See ICP (intracranial pressure)


Interleukin-6. One of a group of related proteins made by leukocytes (white blood cells) and other cells in the body. IL-6 is made mainly by some T lymphocyte. It causes B lymphocytes to make more antibodies and also causes fever by affecting areas of the brain that...


Use of the body's immune system to fight tumors. See biological response modifier. Treatment to boost or restore the ability of the immune system to fight cancer, infections, and other diseases. Also used to lessen certain side effects that may be caused by some...

Implanted Port

A catheter connected to a quarter-sized disk that is surgically placed just below the skin in the chest or abdomen. The catheter tube is inserted into a large vein or artery directly into the bloodstream. Fluids, drugs, or blood products can be infused or blood drawn...


Refers to tumors that cannot be approached by surgical procedure. Tumors that are deep in the brain or beneath vital structures. Inaccessible tumors cannot be approached by standard surgical techniques.


Scientific/medical reason for performing a certain procedure. In medicine, a condition which makes a particular treatment or procedure advisable. A sign or a circumstance which points to or shows the cause, pathology, treatment, or outcome of an attack of disease.


Refers to a tumor that penetrates the normal, surrounding tissue. Tumor that has spread from where it started into surrounding, healthy tissue.

Informed Consent

The right to have information explained to you so that you fully understand and agree to the nature of the proposed treatment. Making a decision about participating in a research study involves understanding the potential risks and benefits as well as your rights and...

Interstitial Radiation Therapy

The implantation of radioactive seeds directly into a tumor. A type of radiation therapy in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a tumor. Also called implant radiation therapy, internal radiation...

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