a test that uses ultrasound waves to create a moving picture of the heart

Identified in a variety of mostly animal proteins, epidermal growth factor (EGF) domains contain between 30 and 40 amino acids. To date their function remains a mystery. Many of the proteins containing an EGF domain require calcium for their biolo...

Of, relating to, or denoting glands that secrete hormones or other products directly into the blood: "the endocrine system".

branch of medicine that deals with the incidence, distribution, and control of diseases. Epidemiological studies deal with health-events, health-characteristics, or health-determinant patterns in a society.

Directly manipulate variables to study their effects; human experiments are usually performed as randomized trials. 

Determinants of some individuals in a population or study, that is studied as a predictor or cause of an outcome (e.g. a risk allele in an aetiologic study, or a drug in an experiment).