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Kolbeck C, Niedermaier I, Deyko A, Lovelock KRJ, Taccardi N, Wei W, Wasserscheid P, Maier F, Steinrück HP. Influence of Substituents and Functional Groups on the Surface Composition of Ionic Liquids. Chemistry 2014; 20:3954-65. [DOI: 10.1002/chem.201304549] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Indexed: 11/10/2022]
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Rietzler F, Piermaier M, Deyko A, Steinrück HP, Maier F. Electrospray ionization deposition of ultrathin ionic liquid films: [C8C1Im]Cl and [C8C1Im][Tf2N] on Au(111). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:1063-1071. [PMID: 24405292 DOI: 10.1021/la404429q] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We introduce a new method for preparing ultrathin ionic liquid (IL) films on surfaces by means of electrospray ionization deposition (ESID) under ultraclean and well-defined ultra-high-vacuum (UHV) conditions. In contrast to physical vapor deposition (PVD) of ILs under UHV, ESID even allows deposition of ILs, which are prone to thermal decomposition. As proof of concept, we first investigated ultrathin [C8C1Im][Tf2N] (=1-methyl-3-octyl imidazolium bis(trifluoromethyl)imide) films on Au(111) by angle-resolved X-ray photoelectron spectroscopy (ARXPS). Films obtained by ESID are found to be virtually identical to films grown by standard PVD. Thereafter, ESID of [C8C1Im]Cl on Au(111) was studied as a first example of an IL that cannot be prepared as ultrathin film otherwise. [C8C1Im]Cl forms a wetting layer with a checkerboard arrangement with the cationic imidazolium ring and the chloride anion adsorbed next to each other on the substrate and the alkyl chain pointing toward vacuum. This arrangement within the wetting layer is similar to that observed for [C8C1Im][Tf2N], albeit with a higher degree of order of the alkyl chains. Further deposition of [C8C1Im]Cl leads to a pronounced island growth on top of the wetting layer, which is independently confirmed by ARXPS and atomic force microscopy. This behavior contrasts the growth behavior found for [C8C1Im][Tf2N], where layer-by-layer growth on top of the wetting layer is observed. The dramatic difference between both ILs is attributed to differences in the cation-anion interactions and in the degree of order in the wetting layer of the two ILs.
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Niedermaier I, Bahlmann M, Papp C, Kolbeck C, Wei W, Krick Calderón S, Grabau M, Schulz PS, Wasserscheid P, Steinrück HP, Maier F. Carbon Dioxide Capture by an Amine Functionalized Ionic Liquid: Fundamental Differences of Surface and Bulk Behavior. J Am Chem Soc 2013; 136:436-41. [DOI: 10.1021/ja410745a] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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79
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Brunner A, Groebner J, Umathum R, Maier F, Semmler W, Bock M. An MR-compatible stereoscopic in-room 3D display for MR-guided interventions. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2013; 27:277-82. [PMID: 24322339 DOI: 10.1007/s10334-013-0423-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 10/10/2013] [Accepted: 11/12/2013] [Indexed: 10/25/2022]
Abstract
BACKGROUND AND METHODS A commercial three-dimensional (3D) monitor was modified for use inside the scanner room to provide stereoscopic real-time visualization during magnetic resonance (MR)-guided interventions, and tested in a catheter-tracking phantom experiment at 1.5 T. Brightness, uniformity, radio frequency (RF) emissions and MR image interferences were measured. RESULTS AND DISCUSSION Due to modifications, the center luminance of the 3D monitor was reduced by 14%, and the addition of a Faraday shield further reduced the remaining luminance by 31%. RF emissions could be effectively shielded; only a minor signal-to-noise ratio (SNR) decrease of 4.6% was observed during imaging. During the tracking experiment, the 3D orientation of the catheter and vessel structures in the phantom could be visualized stereoscopically.
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Krafft AJ, Zamecnik P, Maier F, de Oliveira A, Hallscheidt P, Schlemmer HP, Bock M. Passive marker tracking via phase-only cross correlation (POCC) for MR-guided needle interventions: Initial in vivo experience. Phys Med 2013; 29:607-14. [DOI: 10.1016/j.ejmp.2012.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 09/07/2012] [Accepted: 09/20/2012] [Indexed: 10/27/2022] Open
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81
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Yeniaras E, Fuentes DT, Fahrenholtz SJ, Weinberg JS, Maier F, Hazle JD, Stafford RJ. Design and initial evaluation of a treatment planning software system for MRI-guided laser ablation in the brain. Int J Comput Assist Radiol Surg 2013; 9:659-67. [PMID: 24091853 DOI: 10.1007/s11548-013-0948-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 09/14/2013] [Indexed: 11/28/2022]
Abstract
PURPOSE An open-source software system for planning magnetic resonance (MR)-guided laser-induced thermal therapy (MRgLITT) in brain is presented. The system was designed to provide a streamlined and operator-friendly graphical user interface (GUI) for simulating and visualizing potential outcomes of various treatment scenarios to aid in decisions on treatment approach or feasibility. METHODS A portable software module was developed on the 3D Slicer platform, an open-source medical imaging and visualization framework. The module introduces an interactive GUI for investigating different laser positions and power settings as well as the influence of patient-specific tissue properties for quickly creating and evaluating custom treatment options. It also provides a common treatment planning interface for use by both open-source and commercial finite element solvers. In this study, an open-source finite element solver for Pennes' bioheat equation is interfaced to the module to provide rapid 3D estimates of the steady-state temperature distribution and potential tissue damage in the presence of patient-specific tissue boundary conditions identified on segmented MR images. RESULTS The total time to initialize and simulate an MRgLITT procedure using the GUI was [Formula: see text]5 min. Each independent simulation took [Formula: see text]30 s, including the time to visualize the results fused with the planning MRI. For demonstration purposes, a simulated steady-state isotherm contour [Formula: see text] was correlated with MR temperature imaging (N = 5). The mean Hausdorff distance between simulated and actual contours was 2.0 mm [Formula: see text], whereas the mean Dice similarity coefficient was 0.93 [Formula: see text]. CONCLUSIONS We have designed, implemented, and conducted initial feasibility evaluations of a software tool for intuitive and rapid planning of MRgLITT in brain. The retrospective in vivo dataset presented herein illustrates the feasibility and potential of incorporating fast, image-based bioheat predictions into an interactive virtual planning environment for such procedures.
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Kolbeck C, Deyko A, Matsuda T, Kohler FTU, Wasserscheid P, Maier F, Steinrück HP. Temperature-Dependent Surface-Enrichment Effects of Imidazolium-Based Ionic Liquids. Chemphyschem 2013; 14:3726-30. [DOI: 10.1002/cphc.201300719] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Indexed: 11/09/2022]
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Zhang K, Maier F, Krafft AJ, Umathum R, Semmler W, Bock M. Tracking of an interventional catheter with a ferromagnetic tip using dual-echo projections. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2013; 234:176-183. [PMID: 23892103 DOI: 10.1016/j.jmr.2013.06.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 06/12/2013] [Accepted: 06/25/2013] [Indexed: 06/02/2023]
Abstract
Interventional devices with ferromagnetic components can be manipulated remotely using forces induced by the MRI gradients. To deflect the tip of an endovascular catheter, large ferromagnetic spheres of 2 mm diameter are required to exert sufficiently high magnetic forces; however, tracking of these devices is difficult due to the large image artifacts. In this study, a new dual-echo technique is proposed to improve the stability of localizing and tracking medical devices with ferromagnetic components. MR tracking methods with selective off-resonant excitation and phase compensation with a rephasing gradient can detect ferromagnetic spheres up to a diameter of 1 mm only. In this work, a dual-echo technique is used with two rephasing gradients to stabilize the off-set localization. With rephasing being applied in orthogonal directions, an SNR of 5 was achieved in the signal projections. Compared to a single-echo acquisition the dual-echo method reduces the position error in a phantom from 8 mm to 1.6 mm. In an in vivo study a tracking precision of 4 mm was measured without steering gradients at an image update rate of 2 images per second. Steering experiments were successfully performed with a prototype catheter with ferromagnetic sphere in an aorta phantom and in the vena cava of a pig.
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Niedermaier I, Taccardi N, Wasserscheid P, Maier F, Steinrück HP. Probing a Gas/Liquid Acid-Base Reaction by X-ray Photoelectron Spectroscopy. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201304115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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85
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Niedermaier I, Taccardi N, Wasserscheid P, Maier F, Steinrück HP. Probing a Gas/Liquid Acid-Base Reaction by X-ray Photoelectron Spectroscopy. Angew Chem Int Ed Engl 2013; 52:8904-7. [DOI: 10.1002/anie.201304115] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Indexed: 11/07/2022]
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86
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Dextraze K, Stafford R, Maier F. SU-E-J-59: Visualizing Target Coverage by Iceball During MRI-Guided Cryoablation. Med Phys 2013. [DOI: 10.1118/1.4814271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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87
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Fahrenholtz S, Stafford R, Maier F, Hazle J, Fuentes D. WE-C-116-10: Univariate, Multivariate, and Nonlinear Uncertainty Quantification for Magnetic Resonance-Guided Laser Induced Thermal Therapy. Med Phys 2013. [DOI: 10.1118/1.4815572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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88
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Fahrenholtz SJ, Stafford RJ, Maier F, Hazle JD, Fuentes D. Generalised polynomial chaos-based uncertainty quantification for planning MRgLITT procedures. Int J Hyperthermia 2013; 29:324-35. [PMID: 23692295 DOI: 10.3109/02656736.2013.798036] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE A generalised polynomial chaos (gPC) method is used to incorporate constitutive parameter uncertainties within the Pennes representation of bioheat transfer phenomena. The stochastic temperature predictions of the mathematical model are critically evaluated against MR thermometry data for planning MR-guided laser-induced thermal therapies (MRgLITT). METHODS The Pennes bioheat transfer model coupled with a diffusion theory approximation of laser tissue interaction was implemented as the underlying deterministic kernel. A probabilistic sensitivity study was used to identify parameters that provide the most variance in temperature output. Confidence intervals of the temperature predictions are compared to MR temperature imaging (MRTI) obtained during phantom and in vivo canine (n = 4) MRgLITT experiments. The gPC predictions were quantitatively compared to MRTI data using probabilistic linear and temporal profiles as well as 2-D 60 °C isotherms. RESULTS Optical parameters provided the highest variance in the model output (peak standard deviation: anisotropy 3.51 °C, absorption 2.94 °C, scattering 1.84 °C, conductivity 1.43 °C, and perfusion 0.94 °C). Further, within the statistical sense considered, a non-linear model of the temperature and damage-dependent perfusion, absorption, and scattering is captured within the confidence intervals of the linear gPC method. Multivariate stochastic model predictions using parameters with the dominant sensitivities show good agreement with experimental MRTI data. CONCLUSIONS Given parameter uncertainties and mathematical modelling approximations of the Pennes bioheat model, the statistical framework demonstrates conservative estimates of the therapeutic heating and has potential for use as a computational prediction tool for thermal therapy planning.
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Krafft AJ, Rauschenberg J, Maier F, Jenne JW, Bock M. Crushed rephased orthogonal slice selection (CROSS) for simultaneous acquisition of two orthogonal proton resonance frequency temperature maps. J Magn Reson Imaging 2013; 38:1510-20. [DOI: 10.1002/jmri.24118] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 02/15/2013] [Indexed: 01/05/2023] Open
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Schmidt M, Cubillas AM, Taccardi N, Euser TG, Cremer T, Maier F, Steinrück HP, Russell PSJ, Wasserscheid P, Etzold BJM. Cover Picture: Chemical and (Photo)-Catalytical Transformations in Photonic Crystal Fibers (ChemCatChem 3/2013). ChemCatChem 2013. [DOI: 10.1002/cctc.201390006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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91
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Henn P, D'Andrea A, Claussen M, Ehlken N, Maier F, Naeije R, Nagel C, Prange F, Weidenhammer J, Fischer C, Bossone E, Grünig E. Referenzwerte und beeinflussende Faktoren für die rechtsatriale Größe bei gesunden Erwachsenen bestimmt durch zweidimensionale Echokardiografie. Pneumologie 2013. [DOI: 10.1055/s-0033-1334607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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92
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Schmidt M, Cubillas AM, Taccardi N, Euser TG, Cremer T, Maier F, Steinrück HP, Russell PSJ, Wasserscheid P, Etzold BJM. Chemical and (Photo)-Catalytical Transformations in Photonic Crystal Fibers. ChemCatChem 2013. [DOI: 10.1002/cctc.201200676] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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93
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Uhl B, Cremer T, Roos M, Maier F, Steinrück HP, Behm RJ. At the ionic liquid|metal interface: structure formation and temperature dependent behavior of an ionic liquid adlayer on Au(111). Phys Chem Chem Phys 2013; 15:17295-302. [DOI: 10.1039/c3cp52184b] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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94
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Pedersini P, Maier F, Alessandro G, Maion M, Romano A. [Refractory industrial production, chemical composition, synthesis processes and hygienical aspects in worker health protection]. GIORNALE ITALIANO DI MEDICINA DEL LAVORO ED ERGONOMIA 2012; 34:229-235. [PMID: 23213794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The importance of the refractories sintering and manufacture can be better understood considering that the worldwide refractories consumption is about 2,3 kg per year/human being. The RHI Group, world leader in the refractories production, is present in Italy with the production of refractories for the steel and glass sectors in two important industrial sites, in Marone (Brescia) and in San Vito al Tagliamento (Pordenone) respectively. Describes origin, structure and characteristics of the different refractory materials, with particular focus on the different production technologies used in the manufacture of basic refractories (dolomite refractories) and mixed based on alumina, zirconia and silica. We describe the main hygienistics aspects relevant for the protection to the exposure of the workers involved in described production processes. In the production of dolomite refractories, we present the actions that have been implemented in order to reduce the exposure to the Polycyclic Aromatic Hydrocarbons (PAHs). In this process, we report the results of a decade of exposure's monitoring to polycyclic aromatic hydrocarbons in a group of refractory workers.
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Taccardi N, Niedermaier I, Maier F, Steinrück H, Wasserscheid P. Cyclic Thiouronium Ionic Liquids: Physicochemical Properties and their Electronic Structure Probed by X‐Ray Induced Photoelectron Spectroscopy. Chemistry 2012; 18:8288-91. [DOI: 10.1002/chem.201200971] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Indexed: 11/06/2022]
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96
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Niedermaier I, Kolbeck C, Taccardi N, Schulz PS, Li J, Drewello T, Wasserscheid P, Steinrück HP, Maier F. Inside Cover: Organic Reactions in Ionic Liquids Studied by in Situ XPS (ChemPhysChem 7/2012). Chemphyschem 2012. [DOI: 10.1002/cphc.201290030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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97
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Brunner A, Maier F, Krafft AJ, Semmler W, Bock M. Two eyes see more than one: double echo stereoscopic MRA for rapid 3D visualization of vascular structures. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2012; 25:411-8. [PMID: 22476546 DOI: 10.1007/s10334-012-0313-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Revised: 02/09/2012] [Accepted: 03/01/2012] [Indexed: 11/28/2022]
Abstract
OBJECT A three-dimensional (3D) visualization of the target region during intravascular interventions in real-time is challenging since the acquisition of a time-consuming 3D dataset is required. In this work, a novel stereoscopic double echo sequence for achieving 3D depth perception by sampling only two oblique projection images is presented. MATERIALS AND METHODS A double echo (DE) FLASH pulse sequence was developed to acquire continuously stereoscopic image pairs of the vascular target anatomy. Stereo image data were displayed on a stereoscopic 3D LCD monitor in real time after image reconstruction. Phantom experiments followed by a depth perception test were performed to assess the usability of the stereo image pairs for 3D visualization. In an animal experiment the sequence was tested in vivo and was compared with a slower interleaved (IL) sequence variant. RESULTS In the phantom experiments an SNR difference of 6 % between left and right image was found which did not influence the depth perception. The DE acquisition was superior to the IL sequence (SNR(DE) = 10.3, 2.3 images/s over SNR(IL) = 7.1, 1.7 images/s), and during contrast enhancement the abdominal arterial vasculature was clearly perceived as a 3D structure. CONCLUSION A novel stereoscopic DE pulse sequence can be utilized for the fast 3D stereoscopic visualization of vascular structures in real-time.
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Kolbeck C, Niedermaier I, Taccardi N, Schulz PS, Maier F, Wasserscheid P, Steinrück HP. Inside Back Cover: Monitoring of Liquid-Phase Organic Reactions by Photoelectron Spectroscopy (Angew. Chem. Int. Ed. 11/2012). Angew Chem Int Ed Engl 2012. [DOI: 10.1002/anie.201108841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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99
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Maier F, Lichtblau M, Ehlken N, Fischer C, Becker-Grünig T, Blank N, Fiehn C, Grünig E. Training als Zusatztherapie bei Patienten mit Kollagenose assoziierter pulmonaler Hypertonie. Pneumologie 2012. [DOI: 10.1055/s-0032-1302772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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100
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Eggers C, Pedrosa DJ, Kahraman D, Maier F, Lewis C, Fink GR, Schmidt M, Timmermann L. Serial dopamine-transporter imaging of Parkinson's disease: faster progression of clinical and in-vivo patterns in akinetic-rigid patients. KLIN NEUROPHYSIOL 2012. [DOI: 10.1055/s-0032-1301622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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