Category: Hg-Hx

A repeatedly elevated blood pressure exceeding 140 over 90 mmHg. Chronic high blood pressure can stealthily cause blood vessel changes in the back of the eye (retina), abnormal thickening of the heart muscle, kidney failure, and brain damage. No specific cause for high blood pressure is found in 95 percent of patients. Treatment for high blood pressure involves…

Altitude sickness occurs at high altitude. So what is high altitude? Altitude is defined on the following scale: Most people can go up to 8,000 feet (2,438 meters) with minimal effects. If you have been at that altitude before and had no problems, you can probably return to that altitude without problems if (and only if) you…

A hiccup is an extraordinary type of respiratory movement involving a sudden inspiration (intake of air) due to an involuntary contraction of the diaphragm accompanied by closure of the glottis (the vocal apparatus of the larynx). The abrupt inspiration is the result of a sudden contraction of the diaphragm. Closure of the glottis then halts the incoming air. The column…

Hiccups happen when the diaphragm, the muscle that separates the chest from the abdomen, suddenly contracts. When that happens, air is taken in, and then the voice box closes shut, which is what causes the “hic” sound. There are different types of hiccups, named after how long they last: A “regular” bout of hiccups can last up to 48…

An opening, as in the diaphragm. When there is an unusually wide opening in the diaphragm, there can be a hiatus (or hiatal) hernia. In Latin an hiatus is “an opening, gaping mouth, or chasm.” It is derived from the verb “hiare” meaning “to gape or yawn.” Therefore, a “hiatus” is a gaping opening in anything, such as the opening…

Pertaining to an hiatus, an opening. An hiatal hernia occurs when a part of the stomach protrudes through the diaphragm at the opening where the esophagus normally passes through the diaphragm. “Hiatus” in Latin means an opening.

The gene encoding an enzyme called homogentisate 1,2-dioxygenase (also known as homogentisate oxidase). HGD is located on chromosome 3 in region 3q21-q23. Homogentisate oxidase is active chiefly in the liver and kidneys. It is needed to break down the amino acids phenylalanine and tyrosine. Previous steps convert these two amino acids into a molecule called homogentisic acid. Homogentisate oxidase adds two…

Symbol for the metallic element mercury. The abbreviation “mm Hg” means millimeters of mercury, the height of a column of mercury, as in a blood pressure reading. Mercury is poisonous to people.