Frequency tuning of mechanical responses in the mammalian cochlea

The search for mechanisms responsible for the high sensitivity and sharp frequency tuning of first-order auditory neurons has produced surprising results. The cochlea, the mammalian auditory receptor, responds to acoustic stimuli with a sharply frequency tuned, nonlinear vibration that enhances low level stimuli, but generates appreciable distortion. This highly sensitive mechanical response is achieved by an electro-mechanical feedback process in which outer hair cells reinforce cochlear motion at low stimulus intensities

Concentraciones falsamente elevadas de hemoglobina glicosilada en 2 pacientes diabéticos con hemoglobina fetal persistente / Falsely high levels of glycosilated hemoglobin in 2 diabetic patients with persistent fetal hemoglobin

Two diabetic patients with unusual high levels of glycosilated hemoglobin measured by ion exchange chromatography are described. Further studies revealed a persistence of fetal hemoglobin in both cases. This condition produces falsely high levels of glycosilated hemoglobin, when ion exchange chromatography is used. These cases may be overtreated with risk of hypoglycemia. Patients with inappropiate levels of glycosilated hemoglobin should be investigated for hemoglobinopathies