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sarcoma

(Encyclopedia)sarcoma särkōˈmə [key], highly malignant tumor arising in connective- and muscle-cell tissue. It is the result of oncogenes (the cancer causing genes of some viruses) and proto-oncogenes (cancer c...

Hales, Stephen

(Encyclopedia)Hales, Stephen, 1677–1761, English physiologist and clergyman. From 1709 he was perpetual curate of Teddington. His experimental studies in animal and plant physiology contributed greatly to the pro...

lancelet

(Encyclopedia)lancelet, name for small, fishlike lower chordate (see Chordata), also called amphioxus; it shows many affinities with the vertebrates. There are about 30 lancelet species, most belonging to the genus...

fainting

(Encyclopedia)fainting or syncope sĭngˈkəpē [key], temporary loss of consciousness caused by an insufficient supply of oxygen to the brain. It can be concurrent with any serious disease or condition, such as he...

ephedrine

(Encyclopedia)ephedrine ĭfĕdˈrĭn, ĕfˈĭdrēnˌ [key], drug derived from plants of the genus Ephedra (see Pinophyta), most commonly used to prevent mild or moderate attacks of bronchial asthma. Unlike epinephr...

pancreas

(Encyclopedia)pancreas pănˈkrēəs [key], glandular organ that secretes digestive enzymes and hormones. In humans, the pancreas is a yellowish organ about 7 in. (17.8 cm) long and 1.5 in. (3.8 cm) wide. It lies b...

pharming

(Encyclopedia)pharming färˈmĭng [key], the use of genetically altered livestock, such as cows, goats, pigs, and chickens, to produce medically useful products. In pharming, researchers first create hybrid genes ...

bone

(Encyclopedia)CE5 Bone bone, hard tissue that forms the skeleton of the body in vertebrate animals. In the very young, the skeleton is composed largely of cartilage and is therefore pliable, reducing the incide...

athlete's heart

(Encyclopedia)athlete's heart, common term for an enlarged heart associated with repeated strenuous exercise. As a result of the increased workload required of it, the heart will increase physiologically by enlargi...

shape memory

(Encyclopedia)shape memory, property possessed by certain alloys that allows them to return, when heated, to their original shape after having been deformed. This effect results because, as the alloy is deformed, i...