• Specialty
  • Cardiology
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• General Medicine
  • Diabetes Related Terms
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  • Sample Reports - General Medicine
  • Sample Reports - Allergy / Immunology
  • Sample Reports - Endocrinology

• General Medicine Terms

- H -

• H2-blockers

Medicines that reduce the amount of acid the stomach produces by blocking histamine2, which signals the stomach to make acid.



• Hair cells

Sensory cells of the inner ear, which are topped with hair-like structures (stereocilia), which transform the mechanical energy of sound waves into nerve impulses.



• Halitosis

An oral health condition characterized by consistently odorous breath.



• Hallux rigidus

Loss of range of the movement of the metatarsophalangeal (MTP) joint of the first (great) toe.



• Hamstrings

Muscles located in the posterior compartment of the thigh.



• Haploid

A single set of chromosomes (half the full set of genetic material), present in the egg and sperm cells of animals and in the egg and pollen cells of plants. Human beings have 23 chromosomes in their reproductive cells. Compare diploid.



• Hardy-Weinberg Law

The concept that both gene frequencies and genotype frequencies will remain constant from generation to generation in an infinitely large, interbreeding population in which mating is at random and there is no selection, migration or mutation.



• Hay fever

See rhinitis.



• Headache, primary

Includes tension (muscular contraction), vascular (migraine), and cluster headaches not caused by other underlying medical conditions.



• Headache, secondary (TRACTION HEADACHES OR INFLAMMATORY HEADACHES)

Includes headaches that result from other medical conditions.



• Hearing

Series of events in which sound waves in the air are converted to electrical signals that are sent as nerve impulses to the brain where they are interpreted.



• Hearing aid

Electronic device that brings amplified sound to the ear.



• Hearing disorder

Disruption in the normal hearing process; sound waves are not converted to electrical signals and nerve impulses are not transmitted to the brain to be interpreted.



• Heart block

Interrupted electrical impulse to heart muscles.



• Heart valve prolapse

A condition of the heart valve in which it is partially open when it should be closed.



• Heartbeat

One complete contraction of the heart.



• Heart-lung machine

A machine that performs for the heart during open heart surgery.



• Heberden's nodes

Bony swellings around the margins of joints, associated with degenerative changes of arthritis.



• Hematologic

Having to do with the blood.



• Hematopathology

The study of blood, bone marrow and the organs and tissues that use blood cells to perform their functions.



• Hemoglobin

The red, oxygen-carrying protein found in red blood cells.



• Hemorrhage

The medical term for bleeding.



• Hemorrhoidectomy

The surgical removal of hemorrhoids.



• Hepatitis B Virus

A small DNA virus capable of causing both acute and chronic liver disease, possibly by eliciting tissue damage by the immune system. The virus may also be a risk factor for hepatic carcinoma. It is often transmitted through sexual activity or through exposure to contaminated blood.



• Hepatitis C Virus

An RNA virus related to the pestiviruses and flaviviruses. It is capable of causing both acute and chronic liver disease. As with hepatitis B, the liver damage resulting from this infection may be the result of immune reactivity against virus-infected liver cells.



• Hepatitis E

Virus spread mostly through unclean water. This type of hepatitis is common in developing countries and has not occurred in the United States.



• Hepatologist

Physician who specializes in liver diseases.



• Hepatology

Field of medicine concerned with the functions and disorders of the liver.



• Hereditary mutation

A gene change in the body's reproductive cells (egg or sperm) that becomes incorporated in the DNA of every cell in the body; also called germline mutation.



• Herpesvirus

A family of large DNA viruses that infect a wide range of animal species. Eight distinct types have been associated with a variety of human diseases.



• Heterogeneity

The production of identical or similar phenotypes by different genetic mechanisms.



• Heterozygosity

The presence of different alleles at one or more loci on homologous chromosomes.



• Heterozygote

Having two alleles that are different for a given gene.



• HGP

Human Genome Project.



• HHMI

Howard Hughes Medical Institute.



• High density lipoprotein (HDL)

The 'good' cholesterol that promotes breakdown and removal of cholesterol from the body.



• Hip

The region on each side of the pelvis that is made up of three sections: ilium, ischium, and pubis; the upper part of the femur (upper leg bone) fits into the hip via a ball-and-socket joint; the socket is a cup-shaped bone of the pelvis called the acetab



• Histamine

A chemical present in cells throughout the body that is released during an allergic reaction.



• Hives

See urticaria



• Homeobox

A short stretch of nucleotides whose base sequence is virtually identical in all the genes that contain it. It has been found in many organisms from fruit flies to human beings. In the fruit fly, a homeobox appears to determine when particular groups of genes are expressed during development.



• Homologies

Similarities in DNA or protein sequences between individuals of the same species or among different species.



• Homologous chromosomes

A pair of chromosomes containing the same linear gene sequences, each derived from one parent.



• Homozygote

Having identical alleles at one or more loci in homologous chromosome segments.



• Hormone replacement therapy (HRT)

Use of the female hormones estrogen and progestin (a synthetic form of progesterone) to replace those the body no longer produces after menopause.



• Hormone therapy

The use of hormones, medications, or surgery to suppress (block) or mimic hormones and alter the growth of hormone-sensitive cancer.



• Hormone therapy

Treatment that prevents certain cancer cells from getting the hormones they need to grow.



• Hormones

Chemical substances created by the body that control numerous body functions.



• Hormones

Chemicals produced by glands in the body. Hormones control the actions of certain cells or organs.



• Housekeeping genes

Those genes expressed in all cells because they provide functions needed for sustenance of all cell types.



• HUGO

Human Genome Organization.



• Human chorionic gonadotropin

Hormone produced by the placenta during early pregnancy



• Human gene therapy

Insertion of normal DNA directly into cells to correct a genetic defect.



• Human genome

The full collection of genes needed to produce a human being.



• Human Genome Initiative

Collective name for several projects begun in 1986 to (1) create an ordered set of DNA segments from known chromosomal locations, (2) develop new computational methods for analyzing genetic map and DNA sequence data, and (3) develop new techniques and instruments for detecting and analyzing DNA. This DOE initiative is now known as the Human Genome Program. The national effort, led by DOE and NIH (now including the National Human Genome Research Institute), is known as the Human Genome Project.



• Human Genome Project

An international research effort (led in the United States by the National Institutes of Health and the Department of Energy) aimed at identifying and ordering every base in the human genome.



• Human Herpesvirus 6

A virus of the herpesvirus beta-subfamily, discovered in 1985, that infects more than 95% of people by the age of 2 years. It has been causally associated with roseola, mononucleosis-like illness, inflammation of lymph glands. There is also suggestive evidence for a role in multiple sclerosis.



• Human papillomaviruses (HPVS)

A group of viruses that can cause warts. Some HPVs are sexually transmitted and cause wart-like growths on the genitals. HPV is a major risk factor for cervical cancer.



• Hyaloid canal

Narrow passageway that allows blood to flow through the eye.



• Hybridization

The process of joining two complementary strands of DNA or one each of DNA and RNA to form a double- stranded molecule.



• Hydrocortisone

A hormone secreted by the adrenal cortex which affects metabolism.



• Hydrogen breath test

Test for lactose intolerance that measures breath samples for too much hydrogen.



• Hydrotherapy

Use of water as a medical treatment



• Hyperextension

Active or passive force which takes the joint into extension, but beyond its normal physiological range.



• Hyperglycemia

High levels of glucose in the blood.



• Hyperopia

Farsightedness



• Hyperplasia, endometrial

Excessive growth of cells in the endometrium.



• Hyperthyroidism

A condition marked by excessive secretory activity of the thyroid gland.



• Hypertrophy

An increase in the size of tissue



• Hypogeusia

Diminished sensitivity to taste



• Hypomobility

A decrease in the normal range of joint movement.



• Hypoparathyroidism

A condition caused by the reduction or absence of secretions of the parathyroid gland.



• Hyposmia

Diminished sensitivity to smell



• Hypotension

Abnormally low blood pressure



• Hypothalamus

Small structure at the base of the brain that regulates many body functions, including appetite and body temperature.



• Hypothyroidism

Diminished production of thyroid hormone, leading to thyroid insufficiency.



• Hypoxia

Depletion of oxygen in the cells and tissues



• Hysteroscope

Visual examination of the canal of the cervix and the interior of the uterus using a viewing instrument (hysteroscope) inserted through the vagina.