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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Marine biology 122 (1995), S. 1-11 
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cell growth of a coastal marine diatom, Phaeodactylum tricornutum (stock cultures), and two red tide marine flagellates, Heterosigma akashiwo and Gymnodinium mikimotoi (stock cultures), in the presence of soluble chelated Fe(III)-EDTA (1:2) and of four different phases of ferric oxide colloids were experimentally measured in culture experiments at 20°C under 3000 lux fluorescent light. Soluble Fe(III)-EDTA induced the maximal growth rates and cell yields. The short-term uptake rate of iron by H. akashiwo in Fe(III)-EDTA medium was about eight times faster than that in solid amorphous hydrous ferric oxide (Fe2O3·xH2O) medium. In culture experiments supplied with four different ferric oxide forms, the orders of cell yields are amorphous hydrous ferric oxide〉γ-FeOOH (lepidocrocite)〉Fe5O7(OH)·4H2O (hydrated ferric oxyhydroxide polymer 〉α-FeOOH (goethite). The specific growth rates (μ) at logarithmic growth phase in Fe(III)-EDTA, amorphous hydrous ferric oxide and γ-FeOOH media were significantly greater than those in Fe5O7 (OH)·4H2O and α-FeOOH media. The thermodynamically stable forms such as Fe5O7(OH)·4H2O and α-FeOOH supported a little or no phytoplankton growth. The iron solublities and/or proton-promoted iron dissolution rates of these colloidal ferric oxides in seawater at 20°C were determined by simple filtration techniques involving γ-activity measurements of 59Fe. The orders of solubilities and estimated dissolution rate constants of these ferric oxides in seawater were consistent with that of cell yields in the culture experiments. These results suggest that the availability of colloidal iron to provide a source of iron for phytoplankton is related to the thermodynamic stability and kinetic lability of the colloidal ferric oxide phases, which probably control the uptake rate of iron by phytoplankton.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Marine biology 123 (1995), S. 173-178 
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The bioavailability of iron in seawater filtered through a 0.025-μm filter was investigated using 59Fe-labeled iron uptake by the macroalga Laminaria japonica (Areschoug: Phaeophyta) (collected in the northern Japan Sea 1993) as an assay. About 80% of the iron in the 0.025-μm filtered coastal seawater was soluble and/or small colloidal organically bound iron, associated with natural organic ligands forming complexes with ferric ion. After decomposition of the organic matter by ultraviolet (UV) irradiation, 55% of the iron addition [or 0.6 nM, nearly the concentration of Fe(OH) 2 + in equilibrium with amorphous hydrous ferric oxide in seawater at pH 8.0] in the 0.025-μm filtered coastal seawater was taken up by the macroalga. Since the iron concentrations in the 0.025-μm filtered coastal seawater are 0.1 to 2.0 nM and only 0.6 nM of the iron is likely available to biota over 1 to 2 d, we suggest that only small amounts of bioavailable iron exist in coastal seawater not affected by inflow from land and that a significant fraction of dissolved (〈0.025 μ) iron occurs in forms, such as organic iron complexes, other than the simple hydroxo-complex species predicted by thermodynamic models.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cell growth of a coastal marine diatom, Chaetoceros sociale, in the presence of different premixed organic-Fe(III) complexes [EDTA-Fe(III) (100:1 and 2:1), citric-Fe(III) (100:1) and fulvic-Fe(III) (0.1, 0.2 and 1 ppm C)] and solid amorphous hydrous ferric oxide [am-Fe(III) or Fe(III) hydroxide] were experimentally measured in culture experiments at 10 °C under 3000 lux fluorescent light. Fulvic-Fe(III) (0.1 and 0.2 ppm C) and citric-Fe(III) (100:1) induced maximal cell yields of C. sociale. The order of cell yields was: fulvic-Fe(III) (0.1 and 0.2 ppm C) ≥ citric-Fe(III) (100:1) 〉 EDTA-Fe(III) (2:1) ≫ solid am-Fe(III) 〉 EDTA-Fe(III) (100:1) ≫ fulvic-Fe(III) (1 ppm C). The short-term iron uptake rates by C. sociale in fulvic-Fe(III) (0.1 and 0.2 ppm C) and citric-Fe(III) (100:1) media were about five to six times faster than those in EDTA-Fe(III) (100:1) and solid am-Fe(III) media. The dissociative precipitation rates of premixed organic-Fe(III) complexes in seawater at 10 °C were determined by simple filtration (0.025 μm) involving γ-activity measurements of 59Fe. The order of estimated initial Fe(III) dissociative precipitation rates of these organic-Fe(III) complexes in seawater were nearly consistent with those of cell yields in the culture experiments and short-term iron uptake rates by C. sociale [except for fulvic-Fe(III) (1 ppm C) medium]. In fulvic-Fe(III) (0.1 and 0.2 ppm C), citric-Fe(III) (100:1) and EDTA-Fe(III) (2:1) media, the concentrations of dissolved organic-Fe(III) complexes in initial culture experiments are prone to supersaturate under the culture conditions. The supersaturated dissolved organic-Fe(III) complex in seawater supplies biologically available inorganic Fe(III) species in culture media through its dissociation at high pH and high levels of seawater cations. Therefore, the natural dissolved organic-Fe(III) complexes supplied by riverine input may play an important role in supplying bioavailable iron in estuarine mixing system and coastal waters.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Current Opinion in Structural Biology 1 (1991), S. 384-393 
    ISSN: 0959-440X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Journal of Fermentation and Bioengineering 69 (1990), S. 373 
    ISSN: 0922-338X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Clinica Chimica Acta 151 (1985), S. 17-22 
    ISSN: 0009-8981
    Keywords: Detergent ; Human thyroid peroxidase ; Membrane bound enzyme ; Membrane solubilization ; Trypsin
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Analytica Chimica Acta 271 (1993), S. 25-29 
    ISSN: 0003-2670
    Keywords: Fluorimetry ; Gluconic acid ; Liquid chromatography ; Sea water, Sugar acids ; Waters
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Biochemical and Biophysical Research Communications 164 (1989), S. 1268-1273 
    ISSN: 0006-291X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    Histopathology 46 (2005), S. 0 
    ISSN: 1365-2559
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Aims:  S100 calcium-binding proteins are known to play multiple roles in carcinoma development. In this study, we focused on two kinds of these proteins, S100A2 and S100A6, and investigated their expression in thyroid neoplasms.Methods and results:  We investigated S100A2 and S100A6 expression in 141 thyroid neoplasms by immunohistochemistry. S100A2 was not expressed in normal follicles or follicular tumours, with one exception. Although 89.5% of papillary carcinoma were positive for S100A2, the expression was heterogeneous except in two cases. In anaplastic carcinoma, 78.5% of cases expressed S100A2 diffusely, while the remaining cases were negative. In normal follicles, S100A6 expression was always low, while 8.3% of follicular adenomas and 39.5% of follicular carcinomas showed increased expression. In papillary carcinomas, S100A6 expression was increased in 75% of cases, but in anaplastic carcinomas it was decreased, with only 14.3% showing high expression.Conclusions:  The expression patterns of S100A2 and S100A6 in thyroid neoplasms are unique compared with those of other carcinomas, suggesting that: (i) S100A2 and S100A6 contribute to certain events in papillary carcinoma progression, and (ii) S100A2 expression is one of the biological characteristics of anaplastic carcinoma.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Histopathology 20 (1992), S. 0 
    ISSN: 1365-2559
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Piriform sinus fistulae are an underlying abnormality common in patients with acute suppurative thyroiditis. The fistulae arise from the hypopharynx, and end in or adjacent to the thyroid lobe. These congenital fistulae seem to be remnants of one of the pharyngeal pouches in embryonic development, but their exact origin is still controversial. Resected specimens of the thyroid glands and fistulae from 15 patients were examined immunohistochemically with rabbit antisera to human calcitonin and thyroglobulin. The fistulae were lined by squamous, columnar or ciliated epithelium, and sometimes formed branches in the thyroid lobe. Near the branches solid cell nests existed. Mucous glands, follicular structures and thymic tissue were found in the fistula. The follicular structures stained for thyroglobulin. Immunostaining for calcitonin revealed aggregates of many C cells in the thyroid near the fistula. A few calcitonin-positive cells were also found in the fistula. These findings, along with the anatomical relation of the fistulae to major structures of the neck, strongly suggest that the fistulae are remnants related to the ultimobranchial body, and that the fistulae trace the migration route of the ultimobranchial body to the thyroid gland.
    Type of Medium: Electronic Resource
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