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A sensitive and specific method for the determination of bencyclane in human plasma is presented. Bencyclane was extracted from human plasma with two 3-ml volumes of isooctane and was shaken for 10 min. The organic phase was separated and evaporated to dryness at 40 degrees C under a nitrogen stream. The residue was dissolved and an aliquot was injected into the gas chromatograph. The separation was performed with a DB-17 column with helium as the carrier gas. Nitrogen-selective detection was performed. The quantification was performed with the signal output. The limit of detection was 1 ng/ml. 相似文献
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Direct Synthesis of Orthometallated Ketones of the Type RCO(o-C6H4)Mn(CO)4?nLn (R = Alkyl and Aryl Groups, n = 0, 1, 2, L = Ligand) The starting materials of the type RMn(CO)5?nLn und (C6H5)2 Hg react to the products of the type RCO(o-C6H4)Mn(CO)4?nLn[n = 0, R = Ch3, C2H5, C3H7, C6H5,CH2; R = C6H5, n = 1, L = E(C6H5)3, E = P, As, Sb; R = C6H5, n = 2, L = P(OR′)3, R′ = C6H5, CH3, C2H5, C3H7]. Steps of their complex reaction pathway are proposed. These orthometallated substances have been characterized by means of 1H-n.m.r., i.r. and u.v. spectroscopic measurements. The determination of the molecular structure of the two compounds RCO(o-C6H4)Mn(CO)3L [R = C2H5, L = CO; R = C6H5, L = As(C6H5)3] show that both contain a planar heterocyclic five-membered ring of the type . 相似文献
5.
Julia Post Vanessa Kogel Anja Schaffrath Philipp Lohmann N. Jon Shah Karl-Josef Langen Dieter Willbold Antje Willuweit Janine Kutzsche 《Molecules (Basel, Switzerland)》2021,26(6)
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterised by selective neuronal death in the brain stem and spinal cord. The cause is unknown, but an increasing amount of evidence has firmly certified that neuroinflammation plays a key role in ALS pathogenesis. Neuroinflammation is a pathological hallmark of several neurodegenerative disorders and has been implicated as driver of disease progression. Here, we describe a treatment study demonstrating the therapeutic potential of a tandem version of the well-known all-d-peptide RD2 (RD2RD2) in a transgenic mouse model of ALS (SOD1*G93A). Mice were treated intraperitoneally for four weeks with RD2RD2 vs. placebo. SOD1*G93A mice were tested longitudinally during treatment in various behavioural and motor coordination tests. Brain and spinal cord samples were investigated immunohistochemically for gliosis and neurodegeneration. RD2RD2 treatment in SOD1*G93A mice resulted not only in a reduction of activated astrocytes and microglia in both the brain stem and lumbar spinal cord, but also in a rescue of neurons in the motor cortex. RD2RD2 treatment was able to slow progression of the disease phenotype, especially the motor deficits, to an extent that during the four weeks treatment duration, no significant progression was observed in any of the motor experiments. Based on the presented results, we conclude that RD2RD2 is a potential therapeutic candidate against ALS. 相似文献
6.
Eine Meßapparatur zur Untersuchung des Kriech- und Relaxationsverhaltens von Polymeren unter Torsion
Zusammenfassung Zur experimentellen Bestimmung der Kriechfunktion J(t) und der Relaxationsfunktion G(t) unter Torsionsbelastung der Probe wurde eine Meßapparatur entwickelt. Das mechanisch-elektrische Meßprinzip sowie eine Prozeßrechnerkopplung gestatten einen weitgehend automatischen Meßbetrieb. Änderungen an den physikalischen Versuchsbedingungen können rein Software-seitig durchgeführt werden.Das entsprechende Auswerteprogramm liefert neben numerischen Werten eine Zeichnung der entsprechenden Masterkurven, die mit Hilfe der WLF-Gleichung konstruiert werden.Messungen an kommerziellem PMMA zeigen einen Meßz bereich fürJ(t) von 10–9 bis 10–5 m2/N und für G(t) von 10° bis N 105
N/m2 ; das zugängliche Temperaturintervall liegt zwischen –180 °C und 200 °C. Damit ist der für die meisten Polymere erforderliche Bereich erfaßt.Mit 9 Abbildungenjetzt: KFA Jülich GmbH, Institut für Festkörperforschung (IFF). 相似文献
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Yu. Arestov A. Borovikov E. Kozlovsky A. Minaenko A. Moiseev C. Cochet D. Denegri C. Lewin M. A. Turluer U. Gensch H. J. Grabosch W. Lohmann J. MacNaughton France-USSR Collaboration CERN-USSR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1981,8(4):283-289
New data on the inclusive production of the non-strange resonances ?0(770), ω(783), ?(1020) andf(1270) inK ? p interactions at 32 GeV/c are presented. The inclusive production cross sections are equal to (4.32±0.72) mb, (3.7±1.4) mb, (0.65±0.10) mb and (0.91±0.35) mb respectively. Estimates of the topological cross sections are also obtained. The invariant and non-invariantx-distributions for the vector mesons ?0 and ? indicate the prevalence of forward resonance production in the c.m. system. For the tensorf-meson the rapidity andx-distributions are presented. Thet′-distributions for ?0, ?, andf have exponential slopes of 0.6±0.1 GeV?2, 1.2±0.2 GeV?2, and 0.8±0.5 GeV?2 respectively. The exponential slope ofp T 2 -distribution of thef-meson is equal to (2.3±0.5) GeV?2. 相似文献
8.
Olayide S. Lawal Jörg Storz Derek Lohmann Werner-Michael Kulicke 《European Polymer Journal》2009,45(12):3399-3408
Carboxymethyl cassava starch (CMS) was synthesized and its hydrogels were prepared by cross-linking it with di- or polyfunctional carboxylic acids using glutaric (CASXGLU), suberic (CASXSUB), pimelic (CASXPIM) and butanetetracarboxylic acids (CASBTC) as the cross-linkers. The characterization of the CMS showed that its degree of substitution was 0.86, average molar mass (Mw) was 5.6 × 106 g mol−1 and the 13C NMR showed strong peak at δ = 180.42 ppm which was assigned to the CO carbon in the carboxymethyl group. The absorption under load (AUL) and free swelling capacity (FSC) studies showed that the hydrogels have fast swelling properties and that they reached equilibrium after 1 h. Furthermore, all the hydrogels were sensitive to the increasing salt concentrations and pH of the medium. Both AUL and FSC reduced in saline solution while their values increased in alkaline buffer solutions. The result indicate that the difunctional carboxylic acids produced hydrogels with stronger material functions compared with the polyfunctional carboxylic acid and the order of increases in both AUL and FSC was CASXBTC, CASXPIM, CASXSUB and CASXGLU. 相似文献
9.
Dr. Nicolai Wagner Milena Schuhmacher Annett Lohmann Dr. André Nadler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(68):15483-15487
Photorelease of caged compounds is among the most powerful experimental approaches for studying cellular functions on fast timescales. However, its full potential has yet to be exploited, as the number of caged small molecules available for cell biological studies has been limited by synthetic challenges. Addressing this problem, a straightforward, one-step procedure for efficiently synthesizing caged compounds was developed. An in situ generated benzylic coumarin triflate reagent was used to specifically functionalize carboxylate and phosphate moieties in the presence of free hydroxy groups, generating various caged lipid metabolites, including a number of GPCR ligands. By combining the photo-caged ligands with the respective receptors, an easily implementable experimental platform for the optical control and analysis of GPCR-mediated signal transduction in living cells was developed. Ultimately, the described synthetic strategy allows rapid generation of photo-caged small molecules and thus greatly facilitates the analysis of their biological roles in live cell microscopy assays. 相似文献
10.
Bellm SM Builth-Williams JD Jones DB Chaluvadi H Madison DH Ning CG Wang F Ma XG Lohmann B Brunger MJ 《The Journal of chemical physics》2012,136(24):244301
Cross section data for electron scattering from DNA are important for modelling radiation damage in biological systems. Triply differential cross sections for the electron impact ionization of the highest occupied outer valence orbital of tetrahydrofurfuryl alcohol, which can be considered as an analogue to the deoxyribose backbone molecule in DNA, have been measured using the (e,2e) technique. The measurements have been performed with coplanar asymmetric kinematics at an incident electron energy of 250 eV, an ejected electron energy of 20 eV, and at scattered electron angles of -5°, -10°, and -15°. Experimental results are compared with corresponding theoretical calculations performed using the molecular 3-body distorted wave model. Some important differences are observed between the experiment and calculations. 相似文献