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J W Kane

Publications and source records attributed to J W Kane.

5 recordsLinked to original sources

Method comparison--a different approach.

The commonly accepted method of analysing data from method comparison studies is regression analysis, a method which has limitations. This study illustrates the use of a graphical presentation of data, the difference plot, which can be used as an alternative to least squares regression analysis. The data from comparison studies performed on five methods were analysed both by Deming's regression analysis, with calculation of the correlation coefficient, and by the difference plot. The results show that in most cases much more relevant information was obtained from the difference plot.

Androstenedione

Difference between end-tidal and arterial PCO2 in exercise.

The relation between end-tidal carbon dioxide tension (PETCO2) measured by infrared analysis and arterial carbon dioxide tension (PaCO2) during exercise was systematically examined in five healthy adults at two power outputs (25 and 50% VO2max) and at three frequencies of breathing (15, 30, and 45 breaths/min). PETCO2-PaCO2 varied between -2.5 and +9.1 Torr, was inversely related to the frequency of breathing (r = 0.475), and directly related to tidal volume (VT; r = 0.791) and CO2 output (r = 0.627). An equation was obtained by multiple regression analysis, to predict PaCO2 from PETCO2: PaCO2 = 5.5 +0.90 PETCO2 -0.0021 VT (r = 0.915). The equation was applied to measurements of PETCO2 obtained in two previous studies in 10 subjects in which PaCO2 had been measured, and was found to predict PaCO2 to within 1.04 Torr (+/- SD) for PaCO2 between 25 and 58 Torr (n = 56; r = 0.962). The effect of the response characteristics of the CO2 analyzer on the measurement of PETCO2 was also systematically examined by comparison with a fast-responding respiratory mass spectrometer.

Adult

Use of sodium salicylate as a blocking agent for cortisol-binding-globulin in a radioimmunoassay for cortisol on unextracted plasma.

This report describes investigations into the use of sodium salicylate as a cortisol-binding-globulin blocking agent and the subsequent development of a radioimmunoassay for cortisol on unextracted plasma. Cortisol antiserum was raised against a cortisol 3-O-(carboxy-methyl) oxime-bovine serum albumin conjugate. A 125I-labelled cortisol-tyrosine methyl ester conjugate was also prepared for use in the assay. The radioimmunoassay developed involved no pre-treatment of extraction of the samples before analysis and was extremely simple to perform. Comparison with another radioimmunoassay for cortisol and with the Mattingly fluorimetric assay gave good correlation.

Anilino Naphthalenesulfonates

Determination of hemoglobin-oxygen affinity on micro samples.

The spectrophotometric determination of hemoglobin-oxygen dissociation on dilute red cell suspensions has been modified by the use of a bicarbonate buffer containing bovine serum albumin. The red cell suspension is equillibrated with known ratios of air and nitrogen and 5 per cent carbon dioxide at atmospheric pressure using two gas pumps. The method enables the hemoglobin-oxygen dissociation curve to be measured on 10 to 20 mul of whole blood, and has given values for the P50 (the oxygen tension at 50 per cent hemoglobin-oxygen saturation) of 25.9 plus or minus 1.5 S. D. which are comparable to the value of 26.0 plus or minus 1.0 S. D. obtained by the mixing technique and by other methods. The addition of bovine albumin (35 mg. per cent or greater) increased the P50 by 3 mm. Hg above that obtained with buffer alone. The P50 value has been compared in bis-Tris and phosphate buffers with and without albumin, and in bicarbonate buffers with the addition of approximately equimolar concentrations of either human or bovine serum albumin or polyvinyl-pyrrolidone (PVP), and buffer alone. The effect of albumin on the P50 value was most marked in bicarbonate buffer, and was statistically significantly greater in the presence of human or bovine albumin than in buffer alone or buffer plus PVP. The addition of albumin could not be explained through an alteration of cell shape or volume, but may be an influence on intracellular pH.

Adenosine Triphosphate