- D -
Daily Value (DV): A dietary reference term that appears on food labels indicating
acceptable levels of nutrients and minerals consumed as part of a healthy diet.
Values are often expressed as percentages of a 2,000-calorie per day diet.
Deep Vein Thrombosis (DVT): The formation of a blood clot in a deep vein, generally in the lower
extremities. DVT can cause serious problems if it breaks loose and travels
through the bloodstream to the lung. Symptoms of DVT include swelling, pain
when walking or flexing the foot and sometimes redness in one leg.
Dehydration: Excessive loss of fluid from the body.
Diabetes: Refers to diabetes mellitus or, less
often, to diabetes insipidus. Diabetes mellitus and diabetes insipidus share
the name "diabetes" because they are both conditions characterized by
excessive urination (polyuria). The diabetes mellitus is condition or disease
in which the body is unable to appropriately control blood sugar (glucose)
levels. This may be caused by failure of the pancreas to produce adequate
amounts of insulin.
Diabetes mellitus: Better known just as
"diabetes" -- a chronic disease associated with abnormally high
levels of the sugar glucose in the blood. Diabetes is due to one of two
mechanisms:
(1) Inadequate production of insulin (which is made by the pancreas and lowers blood glucose) or
(2) Inadequate sensitivity of cells to the action of insulin. The two main types of diabetes correspond to these two mechanisms and are called insulin dependent (type 1) and non-insulin dependent (type 2) diabetes. In type 1 diabetes there is no insulin or not enough of it. In type 2 diabetes, there is generally enough insulin but the cells upon it should act are not normally sensitive to its action.
(1) Inadequate production of insulin (which is made by the pancreas and lowers blood glucose) or
(2) Inadequate sensitivity of cells to the action of insulin. The two main types of diabetes correspond to these two mechanisms and are called insulin dependent (type 1) and non-insulin dependent (type 2) diabetes. In type 1 diabetes there is no insulin or not enough of it. In type 2 diabetes, there is generally enough insulin but the cells upon it should act are not normally sensitive to its action.
Diagnosis: 1 The nature of a
disease; the identification of an illness. 2 A conclusion or
decision reached by diagnosis. The diagnosis is rabies. 3 The
identification of any problem. The diagnosis was a plugged IV.
Diaphragm: A
dome shaped muscle that separates the lungs and heart from the abdomen. This
muscle assists in breathing.
Diarrhea: A common condition that involves
unusually frequent and liquid bowel movements. The opposite of constipation.
There are many infectious and noninfectious causes of diarrhea. Persistent
diarrhea is both uncomfortable and dangerous to the health because it can
indicate an underlying infection and may mean that the body is not able to
absorb some nutrients due to a problem in the bowels. Treatment includes
drinking plenty of fluids to prevent dehydration and taking over-the-counter
remedies. People with diarrhea that persists for more than a couple days,
particularly small children or elderly people, should seek medical attention.
Dietitian: A dietitian is a health professional who
is trained to give people advice about what they eat.
Digestive system:
The system by which ingested food is acted upon by physical and chemical
means to provide the body with absorbable nutrients and to excrete waste
products; in mammals the system includes the alimentary canal extending
from the mouth to the anus, and the hormones and enzymes assisting in
digestion.
Dilatation or Dilation: The process of enlargement or expansion.
Diploid: Normal amount of DNA in a cell.
Distal: The more (or most) distant of two (or
more) things. For example, the distal end of the femur (the thigh bone) is the
end down by the knee; the end more distant from the torso. The distal bile duct
is the far end of the cystic duct, the end away from the gallbladder. And the
distal lymph node in a chain of nodes is the most distant one. The opposite of
distal is proximal.
Distal Pancreatectomy: Surgical removal of part of body and entire tail of pancreas.
Diuretic: A
substance that promotes increased urine excretion.
DNA (deoxyribonucleic acid): The part of every cell that carries all genetic information.
Dosage: A
determined amount of a prescribed drug.
Dosimetrist: A
person who plans and calculates the proper radiation dose for treatment.
Double-Blind Trial: A clinical trial in which neither the medical staff nor the trial
participant knows which therapy the participant is receiving. The participant
may receive the standard treatment or the experimental treatment. This prevents
bias on behalf of doctors and participants.
Doubling time: Time it takes the cell population to
double in number.
Duct: A walled passageway, such as a lymph duct,
that carries fluid from one place to another. Also known as a ductus.
Dumping: A
condition in which there is rapid emptying of the stomach shortly after eating.
It may be characterized by flushed skin, weakness, dizziness, abdominal pain,
nausea, vomiting and/or diarrhea.
Duodenum: The first part of the small intestine.
The duodenum is a common site for peptic ulcer formation. The duodenum extends
from the pylorus at the bottom of the stomach to the jejunum, the second part
of the small intestine.
Dysplasia: Abnormal cells that are not cancer.
