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.
Posterior vitreous detachment (PVD) is a change in your eye which does not normally cause sight loss. It is very common and most of us will develop it at some point in our lives. Although it can cause some frustrating symptoms, PVD doesn't cause pain, harm your eye, or change the way your eye works.