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Dr. Franz Schötz 《Planta》1958,52(4):351-392
Ohne ZusammenfassungMit 25 TextabbildungenAls Habilitationsschrift bei der Naturwissenschaftlichen Fakultät der Universität München eingereicht. 相似文献
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Caroline S. Pace Franz M. Matschinsky 《Biochimica et Biophysica Acta (BBA)/General Subjects》1974,354(2):188-193
Cytochalasin B was found to inhibit both glucose-induced spike activity and glucose utilization in isolated rat pancreatic islets under conditions previously shown to increase insulin release (Lacy, P.E., Klein N.J. and Fink. C.J. (1973) Endocrinology 92, 1458–1468). However, cytochalasin B did not prevent the depolarization of islet cells caused by high glucose. The results indicate that neither glycolysis nor spike activity are necessary events leading to insulin release. 相似文献
997.
Characterization of mode II-wear particles and cytokine response in a human macrophage-like cell culture. 总被引:1,自引:0,他引:1
Olaf Rolf Bernd Baumann Thomas Sterner Norbert Schütze Franz Jakob Jochen Eulert Christof Paul Rader 《Biomedizinische Technik》2005,50(1-2):25-29
Informations about wear particles in metallosis (mode II wear) and their effects in vitro and in vivo are limited. The aim of this study was to characterize wear particles obtained intraoperatively and to analyse their effects on cytokine response in an established human macrophage-like cell culture model. METHOD: Wear particles were obtained intraoperatively from four patients with metallosis resulting from CrCoMo/PE/TiAIV-implants (mode II wear) (3 knee, 1 hip prosthesis). After purification, particles were characterized regarding to their composition and size (particle size analyser, electron microscopy, edx-analysis, histological slices). The effects of particles on the release of cytokines (PDGF, IL-1beta, IL-8, TNF alpha) were determined in an established human macrophage-like cell culture system by ELISA-assays. RESULTS: The metal wear particles consisted of TiAIV with a mean size of 0.1 +/- 0.15 microm, independent of the prosthesis location. CrCoMo particles could not be detected. In the cell culture model 1456 x 10(8) particles per 1 x 10(6) macrophages released maximum amounts of TNFalpha (8-fold) and IL-8 and IL-1beta (5-fold) while the survival rate of the cells was more than 90 percent. A particle-dependent increase of PDGF-levels could not be detected. CONCLUSION: As already shown for mode I wear particles (contact between primary bearing surfaces), also mode II wear particles cause release of bone resorbing cytokines in a macrophage-like cell culture model. Because their local and systemic effects in vivo are still not completely understood, we recommend a complete removal of wear particles in cases of metallosis to avoid possible immunological reactions of the body as well as periprosthetic osteolysis. 相似文献
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Fifty-one amphibian breeding sites in northern Wisconsin were sampled in two surveys, in 1986 and 1987, to determine the chemical conditions and amphibian inhabitants present. All twenty-one ponds in 1986 and twenty-eight in 1987 were mildly acidic and sensitive to acidification. The pH levels encountered were generally not toxic to the resident amphibians, and may have been related to levels of phenolics in some cases. Soil type and forest canopy coverage appeared to influence the chemistry of these ponds and a direct relationship of amphibian species richness with pond size was found. Only larger ponds were long-lived enough for metamorphosis of amphibian larvae, suggesting an importance for recruitment. They were also the most sensitive ponds and the only ones to enter the chronically toxic pH range for ambystomatid salamanders, possibly placing them at risk to future acid inputs. 相似文献
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