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Biomedical subjects

H Hutten

Publications and source records attributed to H Hutten.

At least 91 records · Page 5Linked to original sources
PubMed1975

[Validity of pH measurements by means of micro pH combination electrodes in blood and other biological fluids (author's transl)].

pH measurements in blood or in media containing either proteins or polypeptides and performed by means of micro pH combination electrodes type N 58 (Schott & Gen., Mainz) yield in a systematic error according to the regression line y = 1.135 chi - 0.842, in the range between pH 5.3 and 8.3. This deviation from the real pH value is independent of the protein concentration and amounts to 0.1-0.2 pH units in the physiological range. The error does not occur if the pH measurements are performed in media which are free of proteins and polypeptides, respectively. If the electrolyte solution within the reference electrode is replaced (NaCl solution instead of KCl solution) the error is distinctly reduced. For this reason, this deviation should be caused by the variation of the diffusion potential across the platinum junctions.

Diagnostic Errors↗
PubMed1975

Critical diffusion ranges for oxygen and glucose in tumor tissue considering Michaelis-Menten kinetics.

The supply conditions for O2 and glucose in tumor tissue distinctly deteriorate with increasing tumor mass. As a result retardation in growth, lysis and necrosis take place because critical diffusion ranges are partially surpassed in heavier tumors. Applying in vivo-data to a special analogue computer it is possible to investigate the supply conditions including the range of very low O2 tensions and glucose concentrations. Using a definite arrangement of blood vessels it can be shown that the supply conditions only for one of the limiting substrates, i.e. for O2, are better than assumed hitherto. However, even the more realistic model reveals that regional failure in glucose and O2 obligatorily occurs during tumor cell proliferation.

Animals↗