Dictionary

parthenogenesis Development of a germ cell without fertilization. A form of nonsexual reproduction.

Parry disease See goiter, toxic multinodular.

parrot fever See psittacosis.

paroxysmal atrial tachycardia Bouts of rapid, regular heart beating that originate in the upper chamber of the heart (atrium). Abbreviated PAT. PAT is caused by abnormalities in the atrioventricular (AV) node that lead to rapid firing of electrical impulses from the atrium that bypass the AV node under certain conditions, including excess alcohol consumption, stress,…

parotitis Inflammation of the parotid glands, a classic feature of mumps.

parotid gland One of the largest of the three major salivary glands. The parotid glands are located on the sides of the face in front of the ear, below the level of the ear, and behind the jawbone. See also parotitis.

paronychia Inflammation of the folds of tissue surrounding the nail due to infection. The infection may be bacterial (most commonly, Staphylococcus aureus or Streptococcus) or fungal.

Parkinson’s disease A slowly progressive neurologic disease that is characterized by a fixed inexpressive face, tremor at rest, slowing of voluntary movements, gait with short accelerating steps, peculiar posture and muscle weakness (caused by degeneration of an area of the brain called the basal ganglia), and low production of the neurotransmitter dopamine. Most patients are…

parietal pericardium The outer layer of the pericardium. See also pericardium.

parietal lobes A pair of lobes in the cerebral hemisphere of the brain that are involved in sensation, perception, memory, and integrating sensory input, primarily visual input.

parietal bone The bone on the side of the upper skull.

paresthesia An abnormal sensation of the body, such as numbness, tingling, or burning.