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排序方式: 共有658条查询结果,搜索用时 421 毫秒
641.
Luis M. Molina Sungsik Lee Kristian Sell Giovanni Barcaro Alessandro Fortunelli Byeongdu Lee Soenke Seifert Randall E. Winans Jeffrey W. Elam Michael J. Pellin Ingo Barke Viola von Oeynhausen Yu Lei Randall J. Meyer Julio A. Alonso Arantxa Fraile Rodríguez Armin Kleibert Suzanne Giorgio Claude R. Henry Karl-Heinz Meiwes-Broer Stefan Vajda 《Catalysis Today》2011,160(1):965
642.
643.
Claudia Unterberger Florian Luber Anja Demmel Karola Grünwald Ingrid Huber Karl-Heinz Engel Ulrich Busch 《European Food Research and Technology》2014,239(4):559-566
People suffering from food allergy rely on correct food labelling as the ingestion of minimal amounts of the respective allergen can trigger severe allergenic reactions. Probes for the detection of DNA from allergenic fish, shellfish and cephalopod species in food using multiplex ligation-dependent probe amplification were developed. The specificity and the sensitivity of the detection system were investigated. The limit of detection was 20 mg kg?1 for scallop, fish and bivalve species and 100 mg kg?1 for cephalopod, gastropod and crustacean species using self-prepared sushi spiked with the analytes in different concentration levels. The analysis of 10 commercial food samples demonstrates the applicability of the developed method and its suitability for food quality control. Therefore, the method can be used to monitor the compliance with labelling rules regarding food allergens. 相似文献
644.
645.
L Bärfacker A Kuhl A Hillisch R Grosser S Figueroa-Pérez H Heckroth A Nitsche JK Ergüden H Gielen-Haertwig KH Schlemmer J Mittendorf H Paulsen J Platzek P Kolkhof 《ChemMedChem》2012,7(8):1385-1403
Aldosterone is a hormone that exerts manifold deleterious effects on the kidneys, blood vessels, and heart which can lead to pathophysiological consequences. Inhibition of the mineralocorticoid receptor (MR) is a proven therapeutic concept for the management of associated diseases. Use of the currently marketed MR antagonists spironolactone and eplerenone is restricted, however, due to a lack of selectivity in spironolactone and the lower potency and efficacy of eplerenone. Several pharmaceutical companies have implemented programs to identify drugs that overcome the known liabilities of steroidal MR antagonists. Herein we disclose an extended SAR exploration starting from cyano‐1,4‐dihydropyridines that were identified by high‐throughput screening. Our efforts led to the identification of a dihydronaphthyridine, BAY 94‐8862, which is a potent, selective, and orally available nonsteroidal MR antagonist currently under investigation in a clinical phase II trial. 相似文献
646.
Breitner D Turtiainen T Arvela H Vesterbacka P Johanson B Lehtonen M Hellmuth KH Szabó C 《The Science of the total environment》2008,405(1-3):129-139
In order to define the naturally-occurring radioactive materials that are the source of radon in natural environments, a comprehensive analytical (geochemical, physical and chemical) methodology was employed to study sand samples from the Hollola esker in the city of Hollola (Lahti area, Finland). Techniques such as gamma-spectrometry, emanation measurements, sequential chemical extraction, scanning electron microscopy (SEM), electron probe microanalyses (EPMA) and inductively-coupled plasma mass spectrometry (ICP-MS) were used to determine the potential source of radon. Monazite and xenotime, uranium- and thorium-bearing minerals and potential radon sources, occurred in significant amounts in the samples and were also the main reason for the distribution of uranium and thereby radium in separate grain-size fractions. Following deposition, the esker sand has been exposed to no significant weathering, and radium has not therefore been much separated from uranium. However, considering its non-compatibility with crystal lattices, it was recognized rather in easily leachable species (44% of the total (226)Ra) than uranium (21% of the total (238)U) in our analyses. The smallest grain-size fraction of the esker sand had a higher emanation power (0.24) than the other fractions (around 0.17). Due to the small relative proportion of this fraction, however, it contributed only slightly to the total emanation (4%). The emanation power of the leachable species was about three times higher (ca. 0.20) than that of the species tightly bound to the crystal lattice (ca. 0.07). 相似文献
647.
In a previous paper [Opt. Commun.225, 19-30 (2003)] we presented a method to reconstruct two-dimensional complex amplitudes by using the ambiguity function of one-dimensional intensity scans, obtained from two optical setups involving cylindrical lenses. We demonstrate that the internal redundancy of the ambiguity function can be utilized to improve the efficiency of this method even further. We show that the phase reconstruction errors can be minimized with an appropriate algorithm, and we present experimental data that illustrate the efficient reconstruction of a two-dimensional phase element. 相似文献
648.
Karin Thurner Ebrahim Razzazi-Fazeli Karl-Heinz Wagner Ibrahim Elmadfa Wolfgang Luf 《European Food Research and Technology》2007,224(6):797-800
The effect of pan-frying on the formation of cholesterol oxidation products (COPs) in different processed meat samples (beef
patties, braised meat, and fillets of pork) was studied. Samples were pan-fried with or without addition of oil. Different
unsaturated oils (olive oil, corn oil or partly hydrogenated plant oil) were used throughout the study. After extraction,
seven toxicologically relevant COPs were analyzed using LC–MS. Prior to heat processing up to 6.7 mg COPs/kg extracted fat
could be detected in the raw material. Neither the cholestanetriol nor 25-hydroxycholesterol, which are the most cytotoxic
COPs in vitro, were detectable in any sample. Differences in the COPs contents were observed between beef (up to 16.5 mg/kg
extracted fat) and pork (up to 22.2 mg/kg extracted fat) samples. In prepared samples higher COPs content was noted compared
with raw samples. Generally, a certain order of COPs increase dependent on the plant oil used could be recognized: corn oil
< partially hydrogenated plant oil < olive oil. It appears that short heating time, mild heating conditions, and the use of
fresh and shortly stored raw materials keep COPs levels low. 相似文献
649.
Gustav Kloos 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1966,130(2):79-84
Zusammenfassung Die Zusammensetzung des Protein- bzw. Aminosäuregehalts von einem mit Trichloräthylen hergestellten Hopfenextrakt wurde mit Hilfe der Papier- und Säulen-chromatographie qualitativ und quantitativ untersucht. Vergleichsweise wurde auch die Zusammensetzung eines selbst hergestellten Auszuges aus gedarrtem Hopfen ermittelt. Zur Analyse wurden Auszüge mit Wasser, 1/15 m-Phosphatpuffer von pH 5,6 und ungehopfter Bierwürze bei 80°C hergestellt. Die qualitative Zusammensetzung der ninhydrinpositiven Verbindungen nach papierchromatographischer Auftrennung zeigte eine weitgehende Übereinstimmung der untersuchten Proben, wobei Asparagin als stärkste Komponente vertreten war. In den wäßrigen Auszügen wurden die freien Aminosäuren, die 40% des Gesamtstickstoffs der Trockensubstanz ausmachen, quantitativ bestimmt. Als wesentlicher Unterschied ergab sich dabei, daß freies Asparagin im Hopfenauszug in dreifacher Konzentration gegenüber dem Hopfenextraktauszug auftrat. 21 Aminosäuren konnten identifiziert werden, von denen Methionin und Cystin nur in Spuren nachweisbar waren. Nach Hydrolyse mit 6 n-HCI wurden Bausteinanalysen des Gesamtproteins der wäßrigen Lösungen mit Hilfe eines automatischen Aminosäureanalysators durchgeführt. Die toxische Verbindung S-(Dichlorvinyl)-l-cystein konnte in keinem der Auszüge des mit Trichloräthylen hergestellten Hopfenextrakts bzw. in deren Hydrolysaten nachgewiesen werden. 相似文献
650.
Anja Demmel Christine Hupfer Ulrich Busch Karl-Heinz Engel 《European Food Research and Technology》2012,235(1):61-66
In the European Union, labelling of the 14 food allergens listed in Annex IIIa of Directive 2000/13/EC is mandatory. The implementation of upper limits for these allergens is under discussion. Therefore, quantitative analytical methods will be needed to verify compliance with regulatory requirements and to provide an improved basis for the legal assessment of allergen labelling. In this study, the lupine flour content in wheat flours was determined using real-time PCR and statice seeds as internal standard material. The method proved to be applicable to the quantification of lupine contents from 1 to 10?mg/kg, which is in the range relevant for allergic consumers. 相似文献