Category: N

The outer surface of the occipital bone between the foramen magnum and superior nuchal fine.  

A placenta that does not shed the maternal portion.  

In the embryo, one of two horseshoe-shaped depressions on the ventrolateral surface of the head bounded by lateral and median nasal processes. It gives rise to nostrils and a portion of the nasal fossa.  

Circumscribed inflammation of cutaneous veins resulting in nodules that ulcerate.  

Pericarditis due to invasion of the pericardium by cancer.  

A hole through the nasal septum, usually the result of chronic inflammation caused by infection or repeated cocaine inhalation.  

Any peptide that stimulates the kidneys to excrete salt and water.  

The interval on the electrocardiogram that follows a premature atrial contraction (PAC). Because PACs reset the sinus pacemaker, the next sinus beat does not appear when it would have if there had been no extra beat.  

Paralysis caused by lesion of nuclei in the central nervous system.  

A form of paresthesia characterized by numbness, especially at night.