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Sebastien Hascoet MD Alain Fraisse MD PhD Meyer Elbaz MD PhD 《Catheterization and cardiovascular interventions》2013,82(4):E598-E602
Percutaneous transcatheter closure of a patent foramen ovale (PFO) remains challenging when femoral venous approach is not available. We describe the successful closure of a PFO using the right internal jugular venous approach and a deflectable catheter delivery system in a patient with a PFO, recurrent stroke, and an inferior vena cava filter. © 2013 Wiley Periodicals, Inc. 相似文献
993.
S Fournier M Lepainteur N Kassis-Chikhani M Huang C Brun-Buisson V Jarlier;for the AP-HP Outbreaks Control Group 《Journal of travel medicine》2012,19(5):320-323
Assistance Publique-H?pitaux de Paris launched a specific strategy to survey and control the spread of emerging multidrug-resistant bacteria such as carbapenemase-producing Enterobacteria (CPE). Among the 63 CPE events that occurred between 2004 and 2011, 87% involved patients with a link with cross-border exchanges, justifying the recommendation to screen and isolate such patients. 相似文献
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Alison E. Murray Fabien Kenig Christian H. Fritsen Christopher P. McKay Kaelin M. Cawley Ross Edwards Emanuele Kuhn Diane M. McKnight Nathaniel E. Ostrom Vivian Peng Adrian Ponce John C. Priscu Vladimir Samarkin Ashley T. Townsend Protima Wagh Seth A. Young Pung To Yung Peter T. Doran 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(50):20626-20631
The permanent ice cover of Lake Vida (Antarctica) encapsulates an extreme cryogenic brine ecosystem (−13 °C; salinity, 200). This aphotic ecosystem is anoxic and consists of a slightly acidic (pH 6.2) sodium chloride-dominated brine. Expeditions in 2005 and 2010 were conducted to investigate the biogeochemistry of Lake Vida’s brine system. A phylogenetically diverse and metabolically active Bacteria dominated microbial assemblage was observed in the brine. These bacteria live under very high levels of reduced metals, ammonia, molecular hydrogen (H2), and dissolved organic carbon, as well as high concentrations of oxidized species of nitrogen (i.e., supersaturated nitrous oxide and ∼1 mmol⋅L−1 nitrate) and sulfur (as sulfate). The existence of this system, with active biota, and a suite of reduced as well as oxidized compounds, is unusual given the millennial scale of its isolation from external sources of energy. The geochemistry of the brine suggests that abiotic brine-rock reactions may occur in this system and that the rich sources of dissolved electron acceptors prevent sulfate reduction and methanogenesis from being energetically favorable. The discovery of this ecosystem and the in situ biotic and abiotic processes occurring at low temperature provides a tractable system to study habitability of isolated terrestrial cryoenvironments (e.g., permafrost cryopegs and subglacial ecosystems), and is a potential analog for habitats on other icy worlds where water-rock reactions may cooccur with saline deposits and subsurface oceans. 相似文献
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Laurent Gueudré Tomas Binder Christian Chmelik Florian Hibbe Douglas M. Ruthven J?rg K?rger 《Materials》2012,5(4):721-740
Because of the small particle size, orientation-dependent diffusion measurements in microporous materials remains a challenging task. We highlight here the potential of micro-imaging by interference microscopy in a case study with MFI-type crystals in which, although with different accuracies, transient concentration profiles in all three directions can be observed. The measurements, which were performed with “rounded-boat” shaped crystals, reproduce the evolution patterns of the guest profiles recorded in previous studies with the more common “coffin-shaped” MFI crystals. The uptake and release patterns through the four principal faces (which in the coffin-shaped crystals extend in the longitudinal direction) are essentially coincident and there is no perceptible mass transfer in the direction of the long axis. The surface resistances of the four crystal faces through which mass transfer occurs are relatively small and have only a minor effect on the mass transfer rate. As a result of the pore structure, diffusion in the crystallographic c direction (which corresponds to the direction of the long axis) is expected to be much slower than in the transverse directions. This could explain the very low rate of mass transfer observed in the direction of the long axis, but it is also possible that the small end faces of the crystal may have high surface resistance. It is not possible to distinguish unequivocally between these two possibilities. All guest molecules studied (methyl-butane, benzene and 4-methyl-2-pentyne) show the same orientation dependence of mass transfer. The long 4-methyl-2-pentyne molecules would be expected to propagate at very different rates through the straight and sinusoidal channels. The coinciding patterns for uptake through the mutually perpendicular crystal faces therefore provide clear evidence that both the coffin shaped crystals and the rounded-boat-shaped crystals considered in this study, must be intergrowths rather than pure single crystals. 相似文献
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