The diseases have been categorized as patches (cause dead spots or patches in the lawn), rings (cause rings of dead or affected grass), or leaf blight (affect individual blades of grass, often over a wide area and no distinct patch or ring pattern may be noticeable).
PVR, abbreviation for pulmonary vascular resistance. To measure changes in blood vessel size or changes in gas volume in the lungs to assist in diagnosing diseases such as deep vein thrombosis (DVT), chronic obstructive pulmonary disease (COPD), and some peripheral vascular disorders. Veins, arteries, and lungs. None.
PERIVENTRICULAR LEUKOMALACIA. Periventricular leukomalacia (PVL) is a form of ischemic white matter damage, which affects premature infants especially ones with cardiorespiratory abnormalities and sepsis. It develops usually in the neonatal period but may also occur in utero and is frequent in mature infants with congenital heart disease.