1,721,002 research outputs found
Quantification and localization of galactose-specific binding sites in rat liver during postnatal development.
Preclustered receptor arrangement is a prerequisite for galactose-specific clearance of large particulate ligands in rat liver
Preclustered receptor arrangement is a prerequisite for galactose-specific clearance of large particulate ligands in rat liver.
Quantification and localization of galactose-specific binding sites in rat liver during postnatal development
Independent modulation of galactose-specific receptor expression in rat liver cells
The expression of galactose-specific receptors on liver cells from rats at the end of pregnancy and from estrogen-treated animals was studied. The number and distribution of binding sites were estimated on hepatocytes and Kupffer and endothelial cells in vitro as well as in situ by means of protein-gold complexes. Hepatocytes and endothelial cells from pregnant rats showed an increased binding activity of at least three times for hepatocytes and one and a half times for endothelial cells with respect to normal rat livers. The increase in the hepatocyte receptor expression was paralleled by an increase in the level of its specific messenger RNA (mRNA). On Kupffer cells, a decreased number of binding sites, at least three times less than control values, was measured. The correlation between the altered hormonal level during pregnancy and the expression of galactose binding sites was examined in hepatocytes and Kupffer cells isolated from virgin rats treated with the synthetic estrogen diethylstilbesterol. In estrogen-treated rats both the binding sites and the specific mRNA of hepatocytes increased as compared with vehicle-treated or untreated animals. In contrast, in Kupffer cells both the estrogen treatment as well as vehicle-only injection led to a significant reduction in the expression of binding sites as compared with virgin untreated animals. To establish whether the decrease of galactose binding sites in Kupffer cells was related to the activation of macrophages or to the removal of plasma membrane caused by enhanced nonspecific phagocytosis, in situ binding experiments were performed after lipopolysaccharide (LPS)-stimulation or latex-bead phagocytosis. Nonspecific phagocytosis does not affect the binding activity, which instead appears strongly reduced after LPS injection. These findings suggest an independent response of galactose-specific receptor expression systems in the different types of liver cells to modulating agents
Biological Stimulation of the Human Skin Applying HealthPromoting Light and Plasma Sources
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
Autoimmune reactions against liver cells by syngeneic neuraminidase-treated lymphocytes.
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