Although "unipolar electrograms" recorded from the His-bundle position have been used to help position catheters for His-bundle ablation, the techniques used to record such electrograms have not been standardized. The effects of five anode locations (right chest wall, anterior chest wall, left chest wall, posterior chest wall, and inferior vena cava) on unipolar atrial, His bundle and ventricul...

BACKGROUND We evaluated the ability of electromechanical mapping of the left ventricle to distinguish between nonviable and viable myocardium in patients with ischemic cardiomyopathy. METHODS AND RESULTS Unipolar voltage amplitudes and local endocardial shortening were measured in 31 patients (mean+/-SD age, 62+/-8 years) with ischemic cardiomyopathy (ejection fraction, 30+/-9%). Dysfunctiona...

To study affect regulation in adults with unipolar (n=38) and bipolar (n=38) forms of childhood-onset depression (COD), as compared with adults with no history of psychiatric illness (n=60), we examined affective modulation of the startle eyeblink reflex. Participants were subjected to binaural bursts of white noise while viewing pictures designed to elicit pleasant, neutral, or unpleasant affe...

The cardiac pacemaker lead, the "Achilles heel" of pacing hardware, is a relatively fragile cable of insulated conductor wire implanted into the hostile environment of the human body [1]. The ideal pacing lead remains an elusive goal. Important lead characteristics include ease of surgical insertion with safe and reliable fixation in the myocardium and a high level of electrical performance [2]...

Hip replacement using hemiarthroplasty (HA) is a common surgical procedure in elderly patients with femoral neck fractures. However, questions remain regarding the choice of unipolar or bipolar HA. A meta-analysis of randomized, controlled trials (RCTs) was performed to determine whether bipolar HA was associated with lower rates of dislocation, reoperation, acetabular erosion, mortality, and g...

Kinetochore reorientation is the critical process ensuring normal chromosome distribution . Reorientation has been studied in living grasshopper spermatocytes, in which bivalents with both chromosomes oriented to the same pole (unipolar orientation) occur but are unstable : sooner or later one chromosome reorients, the stable, bipolar orientation results, and normal anaphase segregation to oppo...