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Georgi C, Hildebrandt A, Tuchscherer A, Oswald S, Lang H. Hexacarbonyl (Trimethylsilyl Ethyne) Dicobalt as MOCVD Precursor for Thin Cobalt Layer Formation. Z Anorg Allg Chem 2013. [DOI: 10.1002/zaac.201300292] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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77
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Gröer C, Brück S, Lai Y, Paulick A, Busemann A, Heidecke CD, Siegmund W, Oswald S. LC-MS/MS-based quantification of clinically relevant intestinal uptake and efflux transporter proteins. J Pharm Biomed Anal 2013; 85:253-61. [PMID: 23973632 DOI: 10.1016/j.jpba.2013.07.031] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 07/19/2013] [Accepted: 07/22/2013] [Indexed: 10/26/2022]
Abstract
Multidrug transporter proteins are crucial determinants in the pharmacokinetics of many drugs. To evaluate their impact on intestinal drug absorption, we developed and validated quantification methods for 10 uptake transporters (OATP1A2, OATP2B1, PEPT1, ASBT, OCT1, OCT3) and efflux transporters (ABCB1, ABCC2, ABCC3, ABCG2) that have been reported to be expressed and to be of clinical relevance in the human intestine. Quantification was performed by targeted liquid chromatography with tandem mass spectrometry (LC-MS/MS)-based quantification of proteospecific peptides after tryptic digestion using stable isotope labeled internal standard peptides. The chromatography of the respective peptides was performed by gradient elution using a reversed phase (C18) column (Kinetex(®), 100 × 3.0 mm, 2.6 μm) and 0.1% formic acid (FA) and acetonitrile with 0.1% FA as mobile phases at a flow rate of 0.5 ml/min. The MS/MS detection was done in the positive multiple reaction monitoring (MRM) mode by monitoring in each case three mass transitions for the transporter-derived peptides and the internal standard peptides. The assays were validated with respect to specificity, linearity (0.1-25 nM), within-day and between-day accuracy and precision as well as stability according to current bioanalytical guidelines. Finally, the developed methods were used to determine the transporter protein content in human intestinal tissue (jejunum and ileum). The methods were shown to possess sufficient specificity, sensitivity, accuracy, precision and stability to measure transporter proteins in the human intestine.
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Kalmar PI, Oswald S, Fuchsjäger MH. [Intramammary angiomatosis at a 53-year-old patient]. ROFO-FORTSCHR RONTG 2013; 185:1103-5. [PMID: 23904200 DOI: 10.1055/s-0033-1335837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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79
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Wolf-Brandstetter C, Oswald S, Bierbaum S, Wiesmann HP, Scharnweber D. Influence of pulse ratio on codeposition of copper species with calcium phosphate coatings on titanium by means of electrochemically assisted deposition. J Biomed Mater Res B Appl Biomater 2013; 102:160-72. [DOI: 10.1002/jbm.b.32992] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 05/08/2013] [Accepted: 05/26/2013] [Indexed: 12/19/2022]
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80
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Helth A, Gostin PF, Oswald S, Wendrock H, Wolff U, Hempel U, Arnhold S, Calin M, Eckert J, Gebert A. Chemical nanoroughening of Ti40Nb surfaces and its effect on human mesenchymal stromal cell response. J Biomed Mater Res B Appl Biomater 2013; 102:31-41. [PMID: 23846980 DOI: 10.1002/jbm.b.32976] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 03/27/2013] [Accepted: 04/21/2013] [Indexed: 12/25/2022]
Abstract
Samples of low modulus beta-type Ti40Nb and cp2-Ti were chemically treated with 98% H2 SO4 + 30% H2 O2 (vol. ratio 1:1) solution. Surface analytical studies conducted with HR-SEM, AFM, and XPS identified a characteristic nanoroughness of the alloy surface related with a network of nanopits of ∼25 nm diameter. This is very similar to that obtained for cp2-Ti. The treatment enhances the oxide layer growth compared to mechanically ground states and causes a strong enrichment of Nb2 O5 relative to TiO2 on the alloy surface. The in vitro analyses clearly indicated that the chemical treatment accelerates the adhesion and spreading of human mesenchymal stromal cells (hMSC), increases the metabolic activity, and the enzyme activity of tissue non-specific alkaline phosphatase (TNAP). Surface structures which were generated mimic the cytoplasmic projections of the cells on the nanoscale. Those effects are more pronounced for the Ti40Nb alloy than for cp2-Ti. The relation between alloy surface topography and chemistry and cell functions is discussed.
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81
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Oswald S, Karsunke XYZ, Dietrich R, Märtlbauer E, Niessner R, Knopp D. Automated regenerable microarray-based immunoassay for rapid parallel quantification of mycotoxins in cereals. Anal Bioanal Chem 2013; 405:6405-15. [PMID: 23620369 DOI: 10.1007/s00216-013-6920-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 03/01/2013] [Accepted: 03/14/2013] [Indexed: 11/30/2022]
Abstract
An automated flow-through multi-mycotoxin immunoassay using the stand-alone Munich Chip Reader 3 platform and reusable biochips was developed and evaluated. This technology combines a unique microarray, prepared by covalent immobilization of target analytes or derivatives on diamino-poly(ethylene glycol) functionalized glass slides, with a dedicated chemiluminescence readout by a CCD camera. In a first stage, we aimed for the parallel detection of aflatoxins, ochratoxin A, deoxynivalenol, and fumonisins in cereal samples in a competitive indirect immunoassay format. The method combines sample extraction with methanol/water (80:20, v/v), extract filtration and dilution, and immunodetection using horseradish peroxidase-labeled anti-mouse IgG antibodies. The total analysis time, including extraction, extract dilution, measurement, and surface regeneration, was 19 min. The prepared microarray chip was reusable for at least 50 times. Oat extract revealed itself as a representative sample matrix for preparation of mycotoxin standards and determination of different types of cereals such as oat, wheat, rye, and maize polenta at relevant concentrations according to the European Commission regulation. The recovery rates of fortified samples in different matrices, with 55-80 and 58-79%, were lower for the better water-soluble fumonisin B1 and deoxynivalenol and with 127-132 and 82-120% higher for the more unpolar aflatoxins and ochratoxin A, respectively. Finally, the results of wheat samples which were naturally contaminated with deoxynivalenol were critically compared in an interlaboratory comparison with data obtained from microtiter plate ELISA, aokinmycontrol® method, and liquid chromatography-mass spectrometry and found to be in good agreement.
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82
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Deng J, Ji H, Yan C, Zhang J, Si W, Baunack S, Oswald S, Mei Y, Schmidt OG. Naturally Rolled-Up C/Si/C Trilayer Nanomembranes as Stable Anodes for Lithium-Ion Batteries with Remarkable Cycling Performance. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201208357] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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83
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Deng J, Ji H, Yan C, Zhang J, Si W, Baunack S, Oswald S, Mei Y, Schmidt OG. Naturally Rolled-Up C/Si/C Trilayer Nanomembranes as Stable Anodes for Lithium-Ion Batteries with Remarkable Cycling Performance. Angew Chem Int Ed Engl 2013; 52:2326-30. [DOI: 10.1002/anie.201208357] [Citation(s) in RCA: 173] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 11/28/2012] [Indexed: 11/08/2022]
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84
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Makharza S, Cirillo G, Bachmatiuk A, Vittorio O, Mendes RG, Oswald S, Hampel S, Rümmeli MH. Size-dependent nanographene oxide as a platform for efficient carboplatin release. J Mater Chem B 2013; 1:6107-6114. [DOI: 10.1039/c3tb21090a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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85
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Leistner K, Lange N, Hänisch J, Oswald S, Scheiba F, Fähler S, Schlörb H, Schultz L. Electrode processes and in situ magnetic measurements of FePt films in a LiPF6 based electrolyte. Electrochim Acta 2012. [DOI: 10.1016/j.electacta.2012.07.055] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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86
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Wolf-Brandstetter C, Hempel U, Clyens S, Gandhi AA, Korostynska O, Oswald S, Tofail SAM, Theilgaard N, Wiesmann HP, Scharnweber D. The impact of heat treatment on interactions of contact-poled biphasic calcium phosphates with proteins and cells. Acta Biomater 2012; 8:3468-77. [PMID: 22613184 DOI: 10.1016/j.actbio.2012.05.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 05/03/2012] [Accepted: 05/07/2012] [Indexed: 01/20/2023]
Abstract
A number of studies have reported improved bone integration for calcium phosphate based materials electrically "poled" by an external electric field prior to implantation. In our study we investigated the effects of electrical polarization of a biphasic ceramic composed of 80% hydroxyapatite and 20% β-tricalcium phosphate. As contact poling involves elevated temperatures as a prerequisite for inducing charge, we used two reference types: samples without any heat treatment and poling, and samples with no poling but heat treatment identical to that of the poled samples. All heat-treated samples (poled or unpoled) showed an improved wettability, which was attributed to a reduced hydrocarbon contamination. Heat treatment alone provoked an accelerated spreading of osteoblast-like cells, whereas on poled samples a retarded cell spreading was observed. While proliferation and several differentiation markers were not influenced by either heat treatment or poling, the release of proinflammatory cytokines interleukin-6 and -8 was significantly reduced for all heat-treated samples, irrespective of additional electrical poling. The study demonstrated that the behaviour of cells in contact with poled biphasic ceramics was influenced by two parameters: heating and charge. Our data revealed that heating of the calcium phosphate ceramics had a much more pronounced effect on cell behaviour than charge.
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87
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Tuchscherer A, Georgi C, Roth N, Schaarschmidt D, Rüffer T, Waechtler T, Schulz SE, Oswald S, Gessner T, Lang H. Ruthenocenes and Half‐Open Ruthenocenes: Synthesis, Characterization, and Their Use as CVD Precursors for Ruthenium Thin Film Deposition. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200601] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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88
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de Clippel F, Dusselier M, Van Rompaey R, Vanelderen P, Dijkmans J, Makshina E, Giebeler L, Oswald S, Baron GV, Denayer JFM, Pescarmona PP, Jacobs PA, Sels BF. Fast and Selective Sugar Conversion to Alkyl Lactate and Lactic Acid with Bifunctional Carbon–Silica Catalysts. J Am Chem Soc 2012; 134:10089-101. [DOI: 10.1021/ja301678w] [Citation(s) in RCA: 295] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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89
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Meyer zu Schwabedissen HE, Oswald S, Bresser C, Nassif A, Modess C, Desta Z, Ogburn ET, Marinova M, Lütjohann D, Spielhagen C, Nauck M, Kroemer HK, Siegmund W. Compartment-specific gene regulation of the CAR inducer efavirenz in vivo. Clin Pharmacol Ther 2012; 92:103-11. [PMID: 22588604 DOI: 10.1038/clpt.2012.34] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Nuclear receptors such as the constitutive androstane receptor (CAR) are central factors that link drug exposure to the activities of drug metabolism and elimination. In order to determine the in vivo effects of efavirenz, a CAR activator, the expression of target genes was determined in duodenal biopsies obtained from 12 healthy volunteers before treatment and after 10 days of treatment with efavirenz; concomitant administration of the cholesterol inhibitor ezetimibe produced no significant difference. However, in in vitro studies, efavirenz significantly increased CYP2B6 expression in several cell types, suggesting that the drug transactivates CAR. This hypothesis is supported by our findings that there is significant induction of CAR target genes in in vivo peripheral blood mononuclear cells (PBMCs) isolated from healthy volunteers treated with multiple doses of efavirenz. The impact of efavirenz on hepatic metabolism in vivo was confirmed by significant changes in plasma 4β-hydroxycholesterol and bilirubin levels and the area under the curve (AUC) of efavirenz. Induction of CYP2B6 mRNA expression correlated with the decrease in the AUC of efavirenz (r = 0.61; P = 0.036). Taken together, our results provide evidence that efavirenz exerts compartment-specific inductive capacity in vivo.
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90
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Oswald S, Oswald F. Improved ARXPS data interpretation using near-surface measuring angles. SURF INTERFACE ANAL 2012. [DOI: 10.1002/sia.4863] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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91
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Dimesso L, Förster C, Jaegermann W, Khanderi JP, Tempel H, Popp A, Engstler J, Schneider JJ, Sarapulova A, Mikhailova D, Schmitt LA, Oswald S, Ehrenberg H. Developments in nanostructured LiMPO4 (M = Fe, Co, Ni, Mn) composites based on three dimensional carbon architecture. Chem Soc Rev 2012; 41:5068-80. [DOI: 10.1039/c2cs15320c] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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92
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Iselt D, Gaitzsch U, Oswald S, Fähler S, Schultz L, Schlörb H. Electrodeposition and characterization of Fe80Ga20 alloy films. Electrochim Acta 2011. [DOI: 10.1016/j.electacta.2011.03.046] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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93
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Oswald S, Nassif A, Modess C, Keiser M, Ulrich A, Runge D, Hanke U, Lütjohann D, Engel A, Weitschies W, Siegmund W. Drug Interactions Between the Immunosuppressant Tacrolimus and the Cholesterol Absorption Inhibitor Ezetimibe in Healthy Volunteers. Clin Pharmacol Ther 2011; 89:524-8. [DOI: 10.1038/clpt.2011.4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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94
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Alyoshin VA, Romanova IP, Mikhailova D, Oswald S, Senyshyn A, Ehrenberg H. Oxygen Nonstoichiometry of Tetragonal La2−xSrxCuO4−δ (x = 0.15−1.2) and in Situ XPS Studies at Elevated Temperatures. J Phys Chem A 2010; 114:13362-9. [DOI: 10.1021/jp108648e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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95
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Arlt M, Haase D, Hampel S, Oswald S, Bachmatiuk A, Klingeler R, Schulze R, Ritschel M, Leonhardt A, Fuessel S, Büchner B, Kraemer K, Wirth MP. Delivery of carboplatin by carbon-based nanocontainers mediates increased cancer cell death. NANOTECHNOLOGY 2010; 21:335101. [PMID: 20657048 DOI: 10.1088/0957-4484/21/33/335101] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Since the activity of several conventional anticancer drugs is restricted by resistance mechanisms and dose-limiting side-effects, the design of nanocarriers seems to be an efficient and promising approach for drug delivery. Their chemical and mechanical stability and their possible multifunctionality render tubular nanomaterials, such as carbon nanotubes (CNTs) and carbon nanofibres (CNFs), promising delivery agents for anticancer drugs. The goal of the present study was to investigate CNTs and CNFs in order to deliver carboplatin in vitro. No significant intrinsic toxicity of unloaded materials was found, confirming their biocompatibility. Carboplatin was loaded onto CNTs and CNFs, revealing a loading yield of 0.20 mg (CNT-CP) and 0.13 mg (CNF-CP) platinum per milligram of material. The platinum release depended on the carrier material. Whereas CNF-CP marginally released the drug, CNT-CP functioned as a drug depot, constantly releasing up to 68% within 14 days. The cytotoxicity of CNT-CP and CNF-CP in urological tumour cell lines was dependent on the drug release. CNT-CP was identified to be more effective than CNF-CP concerning the impairment of proliferation and clonogenic survival of tumour cells. Moreover, carboplatin, which was delivered by CNT-CP, exhibited a higher anticancer activity than free carboplatin.
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Dunsch L, Yang S, Zhang L, Svitova A, Oswald S, Popov AA. Metal sulfide in a C82 fullerene cage: a new form of endohedral clusterfullerenes. J Am Chem Soc 2010; 132:5413-21. [PMID: 20345137 DOI: 10.1021/ja909580j] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The row of endohedral fullerenes is extended by a new type of sulfur-containing clusterfullerenes: the metal sulfide (M(2)S) has been stabilized within a fullerene cage for the first time. The new sulfur-containing clusterfullerenes M(2)S@C(82)-C(3v)(8) have been isolated for a variety of metals (M = Sc, Y, Dy, and Lu). The UV-vis-NIR, electrochemical, and FTIR spectroscopic characterization and extended DFT calculations point to a close similarity of the M(2)S@C(82) cage isomeric and electronic structure to that of the carbide clusterfullerenes M(2)C(2)@C(2n). The bonding in M(2)S@C(82) is studied in detail by molecular orbital analysis as well as with the use of quantum theory of atom-in-molecules (QTAIM) and electron localization function (ELF) approaches. The metal sulfide cluster formally transfers four electrons to the carbon cage, and metal-sulfur and metal-carbon cage bonds with a high degree of covalency are formed. Molecular dynamics simulations show that Sc(2)S cluster exhibits an almost free rotation around the C(3) axis of the carbon cage, resulting thus in a single line (45)Sc NMR spectrum.
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97
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Ney S, Raabe C, Breuer U, Laage-Gaupp A, Michaellis U, Oswald S, Schäfer J, Schäfer K, Stein S, Kuhnke N, Berweck S, Mall V, Staudt M. Beeinflusst die kortikospinale (Re)Organisation bei unilateraler Zerebralparese das Ansprechen auf Constraint-Induced Movement Therapy? PHYSIOSCIENCE 2010. [DOI: 10.1055/s-0029-1245405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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98
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Oswald S, Nikolowski K, Ehrenberg H. XPS investigations of valence changes during cycling of LiCrMnO4-based cathodes in Li-ion batteries. SURF INTERFACE ANAL 2010. [DOI: 10.1002/sia.3296] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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99
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Meißner T, Kühnel D, Busch W, Oswald S, Richter V, Michaelis A, Schirmer K, Potthoff A. Physical-chemical characterization of tungsten carbide nanoparticles as a basis for toxicological investigations. Nanotoxicology 2010; 4:196-206. [DOI: 10.3109/17435391003605455] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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100
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Oswald S. Growth studies of Ti-based films deposited on Si and SiO2 using angle-resolved XPS. SURF INTERFACE ANAL 2010. [DOI: 10.1002/sia.3208] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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