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Patrick J. Riss Dr. Fabian Debus Dr. René Hummerich Ulrich Schmidt Dr. Patrick Schloss Dr. Hartmut Lueddens Dr. Frank Roesch Dr. 《ChemMedChem》2009,4(9):1480-1487
N‐4‐Fluorobut‐2‐yn‐1‐yl‐2β‐carbomethoxy‐3β‐phenyltropane (PR04.MZ) has been developed as dopamine transporter (DAT) ligand for molecular imaging. It contains a terminally fluorinated, conformationally constrained nitrogen substituent that is well suited for the introduction of fluorine‐18. The present report describes the pharmacological characterisation of [18F]PR04.MZ. The ligand shows an IC50 value of 2 nM against human DAT, whereas the IC50 value against human serotonin transporter and human noradrenalin transporter are lower (110 nM and 22 nM , respectively). Furthermore, its ex vivo organ distribution, its binding profile in the rat brain and reversibility of binding were examined. A μPET study illuminates a fast kinetic profile and specific binding to rat DAT. 相似文献
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Imad Ibrahim Yang Zhang Alexey Popov Lothar Dunsch Bernd Büchner Gianaurelio Cuniberti Mark H Rümmeli 《Nanoscale research letters》2013,8(1):265
All-carbon single-walled carbon nanotubes (SWCNTs) were successfully synthesized, nucleated using a fullerene derivative. A systematic investigation into the initial preparation of C60 fullerenes as growth nucleators for the SWCNTs was conducted. Enhancement in the yield of the produced SWCNT has been achieved with exploring different dispersing media for the fullerenes, the period, and environment of the initial thermal treatment of the fullerenes in addition to the use of different fullerene-based structures. The systematic studies significantly advance our understanding of the growth of the all-carbon catalyst-free single-walled carbon nanotubes. Field-effect transistors were fabricated using the catalyst-free SWCNT and then electrically characterized, showing current capacity as high as the well-studied catalyst-assisted nanotubes. 相似文献
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Dr. phil. Andreas Walker Prof. Dr. theol. Christof Breitsameter 《Ethik in der Medizin》2013,25(4):301-313
Definition of the problem The present article considers discretions and decision-making processes of full-time hospice staff in ethically relevant situations. We explored by means of a qualitative study that we performed in three hospices in North Rhine—Westphalia how these processes and discretions in practice are specifically constructed. Arguments The medication during the prefinal phase, the use of terminal sedation, and the hydration and nutrition at the end of life resulted as the ethically relevant main areas of activity of the surveyed caregivers. Decisions within these fields are usually collectively taken. The individual discretion of caregivers concerns primarily the style of care and the time management related to the patient. Conclusion The arrangement of the discretions depends often less on a theoretical framework, as models or codes of ethics might suggest, but instead on an adjustment of claims of caregivers in practice, as models of bounded rationality suggest. Therefore, the team in a hospice has a self advisory and corrective function on ethical matters, which in the light of the individual dying of a patient are negotiated again and again. 相似文献
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Univ.-Prof. DI Dr. Helmut Habersack DI Marlene Haimann Ass. Prof. Dr. Sándor Baranya Prof. Dr. János Józsa Mag. Angelika Riegler Dr Christine Sindelar DI Marcel Liedermann Johanna Ficsor Gabriella Mohácsiné Simon HR DI Dr. Michael Hengl 《?sterreichische Wasser- und Abfallwirtschaft》2014,66(9-10):340-347
The multiple uses of the Danube River for navigation, hydropower production and as a drinking water supply influence its ecological quality. Flow restrictions due to regulation as well as impacts on the sediment regime such as retention in the catchment area and interruption of the sediment continuum result in changes of the hydromorphological structures and can produce major problems in the context of sediment management. In light of these facts, cross-border investigations of sediment transport at the Danube River are called for. As there are no uniform research approaches shared by Austria and Hungary, the EU-funded project SEDDON (Sediment Research and Management at the Danube River) aims to compare different monitoring and modeling techniques used to determine sediment transport, and to develop mutual solutions. Further, the laboratory equipment currently used for hydraulic model experiments is evaluated and a research channel with a free flowing discharge of up to 10 m3/s without pumping will be constructed, allowing large-scale joint laboratory tests concerning sediment to be performed. 相似文献
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DI Dr. Christoph Hauer H. Keckeis M. Tritthart M. Liedermann H. Habersack 《?sterreichische Wasser- und Abfallwirtschaft》2012,64(11-12):553-563
In light of the various anthropogenic pressures on our river systems (flood protection, navigation, recreational fisheries) and current legal requirements (European Water Framework Directive), the need for integrative evaluation tools has become increasingly apparent. The so-called habitat modeling approach addresses these integrative efforts to quantify the changing environment for target species (fish, macro-invertebrates), taking into account hydrological and/or morphological changes. Over the course of extensive monitoring on the Danube east of Vienna this specific evaluation tool has been adapted and improved to allow the assessment of river engineering measures in future, especially before their implementation and to determine their potential impacts on the ecological conditions. 相似文献