Dictionary of Tropical Medicine

Ulcer

A visible break in the body's surfaces; e.g. skin, gut, urinary tract, which is not caused by acute trauma.

ULV

(Ultra-low-volume) Application of concentrated insecticidal solutions sprayed sparsely over a large area in a vehicle or aeroplane at dosage rates of 740 ml to 1 litre per hectare for mosquito control. This technique produces very large droplets forming a fog or aerosol of concentrated insecticide.

Undifferentiated

A type of cancer in which the cells have become very primitive and do not look or behave like the cells from which they originated. Usually more malignant than a cancer which is highly differentiated. Anaplastic.

Urticaria

Local itching of the skin often results from an allergic reaction.