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71.
JR Kirsch A Bhardwaj LJ Martin DF Hanley RJ Traystman 《Canadian Metallurgical Quarterly》1997,28(11):2259-64; discussion 2264-5
BACKGROUND AND PURPOSE: We attempted to determine whether N-nitro-L-arginine methyl ester (L-NAME) would improve neurological outcome and whether L-arginine (L-ARG) would worsen neurological outcome after transient global ischemia. METHODS: Halothane-anesthetized cats (n = 6 for each group) were treated with intravenous saline, L-NAME (5 mg/kg or 10 mg/kg), or L-arginine (300 mg/kg) 30 minutes before 10 minutes of ischemia (temporary ligation of the left subclavian and brachiocephalic arteries with hemorrhagic hypotension to 50 mm Hg). At 30 minutes of reperfusion, cats in the L-ARG group were administered an additional 300 mg/kg dose of intravenous L-arginine. RESULTS: Time (mean +/- SE) to isoelectric electroencephalography was similar among groups (saline, 26 +/- 11 seconds; L-NAME-5, 15 +/- 4 seconds; L-NAME-10, 36 +/- 27 seconds; and L-ARG, 22 +/- 7 seconds). At 72 hours, reperfusion pathological injury was severe and neurological deficit score (mean, range) was similar among groups (saline, 38[11 to 70]; L-NAME-5, 52 [40 to 73]; L-NAME-10, 47 [23 to 70]; and L-ARG, 40 [0 to 79]). CONCLUSIONS: Nitric oxide is not important in the mechanism of brain injury after global ischemia in cats. 相似文献
72.
Ralf Bandorf Dr. Wolfgang Diehl Dipl.‐Ing Ulrike Heckmann Dipl.‐Phys. Simone Kondruweit Dr. Andreas Pflug Dr. Harald Holeczek Dipl.‐Ing. Martin Metzner Dr. Udo Klotzbach Dr. Andreas Leson Dr. Otmar Zimmer Dr. 《真空研究与实践》2008,20(5):14-19
Propositions and Trends – With Functional Surfaces into the Future Functional surfaces are the key to innovative products. Already today the properties, lifetime, and costs for most industrial and consumer products are determined by functionalised surfaces. Three Fraunhofer Institutes supported by the BMBF investigated the actual state of the art of production technology regarding functional surfaces, their future perspectives and the research and development demand. The results are published in the study “Production technology for the generation of functional surfaces” available at info@ist.‐ fraunhofer.de and the essentials are summarised in this article. 相似文献
73.
74.
There is an advantage for users of electrospray and nanospray mass spectrometry to have an understanding of the processes involved in the conversion of the ions present in the solution to ions in the gas phase. The following processes are considered: Creation of charge droplets at the capillary tip; Electrical potentials required and possibility of gas discharges; Evolution of charged droplets, due to solvent evaporation and Coulomb explosions, to very small droplets that are the precursors of the gas phase ions; Production of gas phase ions from these droplets via the Ion Evaporation and Charge residue models; Analytical uses of ESIMS of small ions, qualitative and quantitative analysis; Effects of the ESI mechanism on the analysis of proteins and protein complexes; Determination of stability constants of protein complexes; Role of additives such as ammonium acetate on the observed mass spectra. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 28:898–917, 2009 相似文献
75.
Prof. Dr. Udo Gamer 《Forschung im Ingenieurwesen》1987,53(4):118-120
Zusammenfassung Gegenstand der Untersuchung ist die Spannungsverteilung in der unendlichen elastisch-plastischen Scheibe, die durch die Druckbelastung
einer kreisf?rmigen Bohrung hervorgerufen wird. Der Rechnung liegt die Trescasche Flie?bedingung, die zugeordnete Flie?regel
sowie lineare isotrope Verfestigung zugrunde. Bestimmt werden ferner die Restspannungen und die Aufweitung der Bohrung. 相似文献
76.
B.L. Kirsch X. Chen E.K. Richman V. Gupta S.H. Tolbert 《Advanced functional materials》2005,15(8):1319-1327
We examine the effects of controlling nanoscale architecture on the tensile properties of honeycomb‐structured silica/polymer composite films. The hexagonal films are produced using evaporation‐induced self‐assembly and uniaxially strained using a home‐built tensile testing apparatus. Significant differences in the yield strain, failure strain, and tensile moduli between the axes parallel and perpendicular to the film‐deposition direction are observed for the thinnest films examined and are attributed to anisotropy in the film nanostructure that is further characterized with transmission electron microscopy and atomic force microscopy. For properly oriented composites, these films have tensile moduli comparable to the Young's modulus of bulk silica but exhibit failure strains that are about an order of magnitude larger than those seen in typical bulk‐silica systems. The yielding and failure processes are explored using X‐ray diffraction and optical microscopy and are characterized by irreversible changes in the nanoscale architecture. We show that tuning the nanoscale architecture can provide control over the tensile properties of composites, allowing for materials with combinations of stiffness and elasticity unachievable in the analogous bulk systems. 相似文献
77.
Olbrich Robert; Kirsch Peter; Pfeiffer Heiderose; Mussgay Lutz 《Canadian Metallurgical Quarterly》2001,110(1):142
In this study, the authors aimed to identify patterns of autonomic dysfunction and neurocognitive deficit recovery. The authors performed laboratory assessments on 66 patients with schizophrenia immediately after an acute psychotic episode and 6, 12, and 18 months later. Shortly after the psychotic episode, the patients displayed cardiovascular hyperarousal at rest, cardiovascular and electrodermal hyporeactivity during 2 Continuous Performance Tasks (CPTs) and deficits in 2 behavioral CPT measures (i.e., reaction time and omission error rate) compared with 29 normal controls. In the subsequent postpsychotic course, changes indicative of a process of recovery occurred in all measurement areas, although with regard to autonomic hyporeactivity amelioration was limited to a subgroup of schizophrenics with complete and persistent symptomatic remission. Neurocognitive improvement in CPTs did not appear to depend on unimpaired autonomic reactivity mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Udo Hahn 《国际智能系统杂志》1989,4(3):345-393
Semantically driven natural language parsers have found wide-spread application as a text processing methodology for knowledge-based information retrieval systems. It is argued that this parsing technique particularly corresponds to the requirements inherent to large-scale text analysis. Unfortunately, this approach suffers from several shortcomings which demand a thorough reformulation of its paradigm. Incorporating principles from conceptual analysis and word expert parsing in a model of lexically distributed text parsing, the focus of the modifications proposed in this article, is on a clean declarative separation of linguistio and other knowledge representation levels, abstraction mechanisms leading to a small collection of specification primitives for the parser, and an attempt to incorporate linguistic generalizations and modularization principles into the design of a semantic text grammar. A sample parse illustrates the operation and linguistic coverage of a lexically distributed text parser based on these theoretical considerations with respect to the semantic analysis of noun groups, simple assertional sentences, nominal anaphora, and textual ellipsis. 相似文献
79.
Cover Picture: Selective Inhibitors of the Protein Tyrosine Phosphatase SHP2 Block Cellular Motility and Growth of Cancer Cells in vitro and in vivo (ChemMedChem 5/2015)
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80.
Ulf Jenk Udo Zimmermann Uli Uhlig Ralph Schöpke Michael Paul 《Mine Water and the Environment》2014,33(1):39-47
Within the WISMUT environmental remediation programme, the rehabilitation of the former uranium mine at Königstein is a very special case due to its use of underground leaching and its location near the Elbe River. The mine water is acidic, oxidizing, and polluted with uranium and other contaminants, and must be pumped to the surface and treated. In-situ water treatment approaches have been investigated to optimise further flooding and shorten the period of conventional water treatment. In 2010/2011, a field-scale experiment was carried out: about 120 t of alkalinity were successfully injected into the partially flooded mine. Tracer signals and geochemical reactions achieved general expectations. Based on the results, a site-specific technology concept was developed to flood the mine to its natural decant level. 相似文献