The electrophysiologic effects of n-acetylprocainamide (NAPA) and procainamide (PA) were compared in 14 chloralose-anesthetized dogs using intracardiac electrography and programmed stimulation. With five successive sequences of an intravenous bolus followed by a 45-minute infusion, plasma concentrations (Cp) ranged from 1.8 ± 0.1 to 32 ± 2 g/ml for PA and from 8.2 ± 0.3 to 125 i 7 ,ug/ml for NA...

PURPOSE To evaluate the static measurement of the accommodative stimulus-response curve with emoji symbols. METHODS The accommodative stimulus-response curve was measured in 18 subjects using a Hartmann-Shack sensor to obtain the objective accommodative response from the Zernike defocus term. Measurements were acquired at different accommodative demands, from 0 to 3 D with a step of 0.5 D. De...

A new procedure is provided for transferring analyte concentration values from a reference material to production calibrators. This method is robust to calibration curve-fitting errors and can be accomplished using only one instrument and one set of reagents. An easily implemented stochastic approximation algorithm iteratively finds the appropriate analyte level of a standard prepared from a re...

Yeast cells exposed to mercuric chloride suffer irreversible damage to the membrane, resulting in a loss of potassium and cellular anions to the medium. The maximal loss of K(+), but not the time course of K(+) loss is related to the mercury concentration, the relationship following a normal curve on a graph of log-concentration versus effect. It is concluded that the response is all or none fo...

Using 'classical' experimental protocols, a human phase-response curve (PRC) to a single 3-h bright light pulse has been established. When the light pulse was centred slightly before the time of body temperature minimum, the circadian system delayed, whilst a pulse slightly after the minimum advanced it. Maximum phase shifts were about 2 h. When light pulses over 3 successive cycles were used, ...