Learn More
The short-term force-frequency characteristics of canine left ventricular myocardium were examined in both isolated and intact preparations by briefly pertubing the frequency of contraction with early extrasystoles. The maximum rate of rise of isometric tension (Fmas) of the isolated trabeculae carneae was potentiated by the introduction of extrasystoles.(More)
The aim of this study was to estimate the likely effect of reduced travel speeds on the incidence of pedestrian fatalities in Adelaide, Australia. The study was based on the results of detailed investigations of 176 fatal pedestrian crashes in the Adelaide area between 1983 and 1991. The method developed to estimate the effect of reduced travelling speed is(More)
The dynamic geometry of the left ventricle was assessed with the use of chronically implanted pulse-transit ultrasonic dimension transducers. The orientation of the transducers allowed the measurement of left ventricular minor and major axis diameters and equatorial wall thickness in the conscious dog. The left ventricle was modeled as a three-dimensional,(More)
The purpose of this study was to evaluate long-term survival benefits of bypass surgery and angioplasty versus medical therapy in 9263 patients at Duke University Medical Center between 1984 and 1990 with coronary artery disease confirmed by cardiac catheterization to involve one, two, or three vessels. Clinical data were prospectively entered into an(More)
Recent studies have improved our understanding of the diastolic mechnical properties of intact myocardium. In order to obtain meaningful data, pressures external to the heart should be measured, forces and dimensions should be properly normalized, and measurements should be obtained over a wide range of ventricular volumes. Diastolic filling appears to be a(More)
Seven children 1-6 years of age underwent aortic resection and re-anastomosis for coarctation of the thoracic aorta. The excised segments were 1-2 cm long and were dilated in vitro with a Grüntzig balloon catheter less than two hours after resection. A pressure of 4-8 atmospheres was used, and the inflated diameter of the balloon was twice the luminal(More)
trans-3'-Hydroxycotinine (THOC) has been recognized as the most abundant metabolite of nicotine. In an attempt to assess THOC and cotinine (COT) concentrations during nicotine transdermal therapy, we developed a new quantitative gas chromatography-mass spectrometry (GC-MS) method for simultaneous determination of total and free THOC and COT in human urine.(More)
Ventilation with positive end-expiratory pressure (PEEP) is associated with reduced cardiac output, but the mechanisms involved are controversial. Possible explanations include increased intrathoracic pressure, reflex changes in myocardial inotropism, pulmonary vascular obstruction and abnormal ventricular interaction. Three types of conscious canine(More)