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Loss of lipid peroxidation as a histochemical marker for preneoplastic hepatocellular foci of rats
No full textSince it is known that tumor cell membranes have lost the capacity to undergo lipid peroxidation, it seemed of interest to investigate whether the toss of susceptibility to lipid peroxidation represents a tumoral marker appearing in preneoplastic cells together with the other known tumoral markers. A histochemical technique was developed to detect lipid peroxidation in individual cells of liver sections exposed to effective prooxidants. The technique was based on the detection of protein-bound aldehydes (alkenals) with the use of the Schiff's reagent. The latter reagent can also detect carbonyl function present in acyl residues of peroxidized phospholipids of cellular membranes. Liver preneoplastic foci were obtained in rats by the i.p. administration of diethyinitrosamine and of 2-acetylaminofluorene in the diet. Frozen sections of the liver, incubated in the presence of reduced nicotinamide adenine dinucleotide phosphate: iron revealed the presence of areas in which lipid peroxidation had not been induced (Schiff-negative areas). These areas corresponded strictly, in serial sections, to areas that were strongly positive to γ-glutamyltranspeptidase. © 1984, American Association for Cancer Research. All rights reserved
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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