The walls of blood vessels exert resistance to the flow of blood and this rises as the diameters of the vessels diminish. This in turn leads to a rise in blood pressure: the phenomenon may be physiological or pathological.

the extent of the body's IMMUNITY – an indication of its ability to withstand disease. 3) the development in a bacterium (see BACTERIA) of resistance to the effects on it of ANTIBIOTICS.

blocking-off from a person's consciousness of repressed emotions and memories. A psychoanalyst helps the patient to break this resistance and bring the repressed material out into the open. (See also REPRESSED MEMORY THERAPY.)