Survival impact of postoperative radiotherapy in patients with olfactory neuroblastoma: 513 cases from the SEER database.

Pupose: To evaluate the impact of postoperative radiotherapy (PORT) on survival in olfactory neuroblastoma (ONB) patients with different tumor staging.

Material And Methods: Patients with ONB were selected in the Surveillance, Epidemiology and End Results (SEER) database from 2004-2016. Survival analyses were performed using Kaplan-Meier (K-M) method, Cox regression analysis, and competing risk model.

Repolarization interactions between cardiac segments of varying action potential duration.

We studied interactions between action potential duration (APD) disperse zones using a double compartment bath in which an APD lengthening solution (Ni++ 2 mmol/L, in Tyrode's solution) was added to one compartment (which contained a portion of the fiber labeled "segment A") followed by addition of an APD shortening solution (6 to 10 mmol/K+) to the other compartment ("segment B"). Standard microelectrode techniques were used in canine Purkinje fibers. With Ni++ in segment A, there was a dispersion in APD measured at both 50% (APD50) and 95% (APD95) of repolarization.

In vitro characteristics of repolarization abnormality--a possible cause of arrhythmias.

When membrane potential (Vm) remains at depolarized levels for prolonged intervals, quiescence and/or repetitive activations occur. In situ such events would be associated with arrhythmias. One way for such a state to occur is abnormal delay of repolarization leading to marked prolongation of action potential (AP) duration (APD).