| 1. |
- Garte, S, et al.
(författare)
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Metabolic gene polymorphism frequencies in control populations
- 2001
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Ingår i: Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology. - 1055-9965. ; 10:12, s. 1239-1248
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Tidskriftsartikel (refereegranskat)
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| 2. |
- Rehkämper, Mark, et al.
(författare)
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Thallium isotope variations in seawater and hydrogenetic, diagenetic, and hydrothermal ferromanganese deposits
- 2002
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Ingår i: Earth and Planetary Science Letters. - 0012-821X .- 1385-013X. ; 197:1-2
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Tidskriftsartikel (refereegranskat)abstract
- Results are presented for the first in-depth investigation of Tl isotope variations in marine materials. The Tl isotopic measurements were conducted by multiple collector-inductively coupled plasma mass spectrometry for a comprehensive suite of hydrogenetic ferromanganese crusts, diagenetic Fe-Mn nodules, hydrothermal manganese deposits and seawater samples. The natural variability of Tl isotope compositions in these samples exceeds the analytical reproducibility (±0.05‰) by more than a factor of 40. Hydrogenetic Fe-Mn crusts have ε205Tl of +10 to +14, whereas seawater is characterized by values as low as -8 (ε205Tl represents the deviation of the 205Tl/203Tl ratio of a sample from the NIST SRM 997 Tl isotope standard in parts per 104). This 2‰ difference in isotope composition is thought to result from the isotope fractionation that accompanies the adsorption of Tl onto ferromanganese particles. An equilibrium fractionation factor of α1.0021 is calculated for this process. Ferromanganese nodules and hydrothermal manganese deposits have variable Tl isotope compositions that range between the values obtained for seawater and hydrogenetic Fe-Mn crusts. The variability in ε205Tl in diagenetic nodules appears to be caused by the adsorption of Tl from pore fluids, which act as a closed-system reservoir with a Tl isotope composition that is inferred to be similar to seawater. Nodules with ε205Tl values similar to seawater are found if the scavenging of Tl is nearly quantitative. Hydrothermal manganese deposits display a positive correlation between ε205Tl and Mn/Fe. This trend is thought to be due to the derivation of Tl from distinct hydrothermal sources. Deposits with low Mn/Fe ratios and low ε205Tl are produced by the adsorption of Tl from fluids that are sampled close to hydrothermal sources. Such fluids have low Mn/Fe ratios and relatively high temperatures, such that only minor isotope fractionation occurs during adsorption. Hydrothermal manganese deposits with high Mn/Fe and high ε205Tl are generated by scavenging of Tl from colder, more distal hydrothermal fluids. Under such conditions, adsorption is
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| 3. |
- van Kuilenburg, André B P, et al.
(författare)
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Novel disease-causing mutations in the dihydropyrimidine dehydrogenase gene interpreted by analysis of the three-dimensional protein structure
- 2002
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Ingår i: Biochemical Journal. - : Portland Press Ltd.. - 0264-6021 .- 1470-8728. ; 364:Pt 1, s. 157-163
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Tidskriftsartikel (refereegranskat)abstract
- Dihydropyrimidine dehydrogenase (DPD) deficiency is an autosomal recessive disease characterized by thymine-uraciluria in homozygous deficient patients. Cancer patients with a partial deficiency of DPD are at risk of developing severe life-threatening toxicities after the administration of 5-fluorouracil. Thus, identification of novel disease-causing mutations is of the utmost importance to allow screening of patients at risk. In eight patients presenting with a complete DPD deficiency, a considerable variation in the clinical presentation was noted. Whereas motor retardation was observed in all patients, no patients presented with convulsive disorders. In this group of patients, nine novel mutations were identified including one deletion of two nucleotides [1039-1042delTG] and eight missense mutations. Analysis of the crystal structure of pig DPD suggested that five out of eight amino acid exchanges present in these patients with a complete DPD deficiency, Pro86Leu, Ser201Arg, Ser492Leu, Asp949Val and His978Arg, interfered directly or indirectly with cofactor binding or electron transport. Furthermore, the mutations Ile560Ser and Tyr211Cys most likely affected the structural integrity of the DPD protein. Only the effect of the Ile370Val and a previously identified Cys29Arg mutation could not be readily explained by analysis of the three-dimensional structure of the DPD enzyme, suggesting that at least the latter might be a common polymorphism. Our data demonstrate for the first time the possible consequences of missense mutations in the DPD gene on the function and stability of the DPD enzyme.
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| 4. |
- Åmand, Lars-Erik, 1957, et al.
(författare)
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Co-Combustion of Dried Sewage Sludge and Coal The Fate of Heavy Metals
- 2001
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Ingår i: In Proceedings of the 16th International Conference on Fluidized Bed Combustion--FBC01, held in Reno, Nevada, USA, May 13-16, 2001.
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Konferensbidrag (refereegranskat)abstract
- The fate of some selected heavy metals has been investigated during co-combustion of sewage sludge and coal in two fluidised bed combustors: the 12MWth circulating fluidized bed (CFB) boiler at CTH and the laboratory scale unit at IVD. The total and species balances were, in general, fairly well closed, and the increased amounts of heavy metals originating from the input sludge were also found in the exit flows. Volatile species such as Hg and Cd are sensitive to the temperature conditions. Thus, almost no mercury was found in the bottom ash, and a cyclone at 350 °C captured little Hg in comparison to a cyclone and filters at 150 °C. The high particle loading in a CFB appears to contribute essentially to the reduction of the flue gas mercury concentration; the emission is reduced by orders of magnitude compared to a plant with low particle concentration. In most cases investigated the emissions of heavy metals were below the limits related to co-combustion set by the European Union.
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