Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «G»:
G: G stands for guanine, one member of the
base pair G-C (guanine-cytosine) in the DNA. The other base pair in
the DNA is A-T (adenine-thymine).
Each base pair forms a "rung of the DNA ladder." A DNA nucleotide is made of a molecule of sugar, a molecule of phosphoric acid, and a molecule called a ...
G (drug caution code)
G (drug caution code): Abbreviation on a medication that stands for "glaucoma" and indicates the medication can cause problems for a person with this eye disorder. Further, a person with glaucoma might see the generic "C" code on a prescription bottle or vial if the medication might raise the pressu...
g (gram): Symbol for gram, a
unit of measurement of weight and mass in the metric system. In weight, a gram
is equal to a thousandth of a kilogram. In mass, a gram is equal to a thousandth
of a liter (one cubic centimeter) of water at 4 degrees centigrade.
The word "gram" comes from the Late Lati...
G protein: These molecules have
been described as "biological traffic lights." Located
inside the cell, G proteins are able respond to signals
outside the cell -- light, smell, hormones -- and translate
(transduce) these signals into action within the cell.
Alfred G. Gilman and Martin Rodbell ...
G-CSF: Granulocyte colony-stimulating factor. A colony-stimulating factor that stimulates the production of neutrophils (a type of white blood cell). G-CSF is a cytokine that belongs to the family of drugs called hematopoietic (blood-forming) agents. Also called filgrastim....
G6PD deficiency: Deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD), the most common enzyme defect of medical importance. About 10 percent of American black males have G6PD deficiency, as do a lesser percent of black females. G6PD deficiency is also increased in frequency in people of...
GAD: Generalized anxiety disorder....
Gage, Phineas: The most famous patient to have survived severe damage to the brain and the first from whom something was learned about the relation between personality and the function of the front parts (the frontal lobes) of the brain.
During work on a railroad in 1848, an unplanned explosion prop...
Gain-of-function mutation: A mutation that confers new or enhanced activity on a protein. Loss-of-function mutations, which are more common, result in reduced or abolished protein function....
Gait: A manner of walking. Observation of the gait can provide clues to a number of diagnoses including Parkinson disease, cerebral palsy, congenital dislocation of the hip, and stroke....
Gait, steppage: See Steppage gait....
Galactorrhea: The spontaneous flow of milk from the nipple at any time other than during nursing.
Galactorrhea can be due to "normal" factors such as an unrecognized pregnancy, trauma, surgery, overexercise or one of a number of drugs (including amphetamine, cimetidine, female hormone replacement th...
Galactose: A sugar contained in milk. Galactose makes up half of the sugar called lactose that is found in milk. Lactose is called a disaccharide, the prefix "di" meaning 2, since lactose is made up of two sugars, galactose and glucose, bound together.
Galactose is metabolized (used) through the ac...
Galactosemia: A genetic metabolic disease in which there is a defect in the body's ability to use the sugar galactose. In classic galactosemia, the basic defect is a deficiency of the enzyme known as GALT (galactose-1-phosphate uridyl transferase). This causes an accumulation of galactose 1-phospha...
Galen: Greek physician and philosopher (born about 129 AD, died about 210 AD) known among other things for his discovery of blood in human arteries and for his dissection of the human cranial nerves, the nerves that supply key areas of the head, face, and upper chest.
The son of Nicon, a well-to-do ...