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S Johnsen

Publications and source records attributed to S Johnsen.

42 records · Page 3Linked to original sources
PubMed1974

HeLa cell plasma membranes. I. 5'-Nucleotidase and ouabain-sensitive ATPase as markers for plasma membranes.

A method for the preparation of HeLa cell plasma membrane ghosts is described. The purity of the plasma membrane fraction was examined by phase contrast and electron microscopy, by chemical analysis, and by assay of marker enzymes. Data on the composition of the plasma membrane fraction are given. It was observed that the distribution pattern of 5'-nucleotidase activity among the subcellular fractions differed from that of ouabain-sensitive ATPase. In addition, the specific activity of 5'-nucleotidase did not follow the distribution of the membrane ghosts. Thus, this enzyme would seem unsuitable as a plasma membrane marker. A complete balance sheet for marker enzyme activities during the fractionation is necessary for the calculation of increase in specific activity because the activities of both 5'-nucleotidase and ouabain-sensitive ATPase might change during the fractionation procedures.

Adenosine Triphosphatases↗
PubMedDate not supplied

Mondini cochlea in Pendred's syndrome. A histological study.

In the past the Mondini malformation of the cochlea has been described histologically on the basis of findings in one temporal bone from a patient with confirmed Pendred's syndrome. The present study presents the histological examination of six temporal bones from 5 patients with confirmed Pendred syndrome. The characteristic Mondini cochlea was found in all preparations. It is concluded that the inner ear malformation in Pendred's syndrome is more in accordance with Mondini's original description than in other syndromes in which a Mondini-like cochlea has been described.

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