Tympanic membrane retraction tensa. Tympanic membrane retraction is fairly common and has been observed in one quarter of a population of British school children. Retraction of both eardrums is less common than having a retraction in just one ear. It is more common in children with cleft palate. Tympanic membrane retraction also occurs in adults. Attempts have been made to categorise the extent of tympanic membrane retraction though the validity of these classifications is limited. The majority of tympanic membrane retractions do not cause any symptoms. Some cause hearing loss by restricting sound-induced vibrations of the eardrum. Permanent conductive hearing loss can be
Plasma membrane Ca2+ ATPase to involve the lymph nodes, and are more common among young women, which could help explain their worse prognosis compared with postmenopausal women. PMCAs were first discovered in the 1960s in the membranes of red blood cells. The presence of an ATPase was discovered in the membranes in 1961, and then in 1966 it was discovered that these ATPases pump Ca out of the cytosol. PMCA was first purified from red blood cell membranes in 1979. Plasma membrane Ca2+ ATPase The plasma membrane Ca ATPase (PMCA) is a transport protein in the plasma membrane of cells and functions to remove