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101.
Christoph Seger Harald R?mpp Sonja Sturm Ernst Haslinger Peter C Schmidt Franz Hadacek 《European journal of pharmaceutical sciences》2004,21(4):453-463
Supercritical fluid extracts (carbon dioxide without modifiers) of St. John's Wort (Hypericum perforatum L., Clusiaceae) were analyzed by GC-MS, HPLC-DAD and HPLC-DAD-MS. Besides the dominating phloroglucinols hyperforin (36.5 +/- 1.1%) and adhyperforin (4.6 +/- 0.1%), the extracts mainly contained alkanes (predominantly nonacosane), fatty acids and wax esters. The apolar components tended to accumulate in a waxy phase resting a top of the hyperforin-enriched phase. No components of higher polarity like naphthodianthrones were found. A set of hyperforin oxidation products was detected and tentatively assigned using HPLC-MS. 相似文献
102.
Harald J J Moonen Edwin J C Moonen Lou Maas Jan W Dallinga Jos C S Kleinjans Theo M C M de Kok 《Food and chemical toxicology》2004,42(6):869-878
2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a mutagenic and carcinogenic heterocyclic amine formed during ordinary cooking, and is subsequently metabolically activated by cytochrome P4501A2 (CYP1A2) and N-acetyltransferase 2 (NAT2). Respective genes encoding for these enzymes, display polymorphic distribution in the human population and are thus believed to cause interindividual differences in cancer risk susceptibility. The present study investigated the influence of dietary exposure and CYP1A2 and NAT2 genotypes and phenotypes on differential urinary PhIP excretion levels in 71 human volunteers after consumption of either a high (7.4 ng/g) or low (1.7 ng/g) dose of PhIP. Urinary PhIP excretion levels were found to reflect recent dietary exposure levels, with average levels of 174% (high dose group) and 127% (low dose group), as compared to pre-feed levels. Urinary caffeine metabolite ratios were significantly different between the two NAT2 genotypes, whereas for CYP1A2, the apparent difference in metabolic ratios between the genotypes was statistically non-significant. Significant correlations were firstly found between the CYP1A2-164A-->C (CYP1A2*1F) polymorphism and differential urinary PhIP excretion levels. Although the found correlations are driven primarily by a small number of subjects possessing the homozygous variant constellation, the strong influence of this genotype indicates that the CYP1A2*1F polymorphism could play an important role in human cancer risk susceptibility. 相似文献
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Monatsschrift Kinderheilkunde - Bei kinderkardiologischen Patienten bzw. Kindern mit angeborenen Herzfehlern werden häufig diagnostische oder therapeutische Prozeduren durchgeführt, die... 相似文献
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Philipp Tschandl Hubert Pehamberger Harald Kittler 《Journal der Deutschen Dermatologischen Gesellschaft》2013,11(3):251-256
Background and objectives: The aim of this study is to show data regarding trends in the diagnosis of melanoma over the last ten years by looking at the University Clinic of Dermatology in Vienna as an example. Patients and methods: All excised melanocytic lesions from 1998 to 2008 were included. Results: The ratio of excisions of benign to malignant lesions fell from 7:1 (1998) to 4:1 (2008). The mean percentage of in situ melanomas was 39% in 1998 and did not change significantly over time and no change was seen in tumor thickness of invasive melanomas. The median invasion depth was 0.7 mm in 1998 and 0.65 mm in 2008. The absolute number of diagnosed melanomas did not change significantly over time. Conclusion: The proportion of in situ melanomas was consistently high. Tumor thickness stayed at a low level, whereas the number of excised benign melanocytic lesions decreased significantly. 相似文献
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Claudia Matschegewski Susanne Staehlke Harald Birkholz Regina Lange Ulrich Beck Konrad Engel J. Barbara Nebe 《Materials》2012,5(7):1176-1195
Microtexturing of implant surfaces is of major relevance in the endeavor to improve biorelevant implant designs. In order to elucidate the role of biomaterial’s topography on cell physiology, obtaining quantitative correlations between cellular behavior and distinct microarchitectural properties is in great demand. Until now, the microscopically observed reorganization of the cytoskeleton on structured biomaterials has been difficult to convert into data. We used geometrically microtextured silicon-titanium arrays as a model system. Samples were prepared by deep reactive-ion etching of silicon wafers, resulting in rectangular grooves (width and height: 2 µm) and cubic pillars (pillar dimensions: 2 × 2 × 5 and 5 × 5 × 5 µm); finally sputter-coated with 100 nm titanium. We focused on the morphometric analysis of MG-63 osteoblasts, including a quantification of the actin cytoskeleton. By means of our novel software FilaQuant, especially developed for automatic actin filament recognition, we were first able to quantify the alterations of the actin network dependent on the microtexture of a material surface. The cells’ actin fibers were significantly reduced in length on the pillared surfaces versus the grooved array (4–5 fold) and completely reorganized on the micropillars, but without altering the orientation of cells. Our morpho-functional approach opens new possibilities for the data correlation of cell-material interactions. 相似文献
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