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141.
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Stuart A. Steinberg 《代数通讯》2013,41(10):3455-3473
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Gerhard Friedrich Thorsten Rose Alexander Wawkuschewski Sabine Kafert-Kasting Britta Laube Lubomir Arseniev Klaus Rissler 《Chromatographia》2008,67(1-2):31-39
In a recently published paper development of a sensitive automated “on-line” solid-phase extraction (SPE)/RP-HPLC assay for
6β-hydroxytestosterone (6β-OHT) with corticosterone as the internal standard (IS) was reported and its potential for quantification
of various testosterone metabolites in culture media reflecting metabolic activity of cultured human and animal hepatocytes
demonstrated [1]. In this following contribution the technique has been extended to determination of another five testosterone metabolites
in cultured rat hepatocytes using an identical “on-line” SPE/RP-HPLC procedure and detection by tandem MS-MS with an atmospheric
pressure chemical ionization (APCI) source in the selected reaction monitoring (SRM) mode as that described in [1]. All six testosterone metabolites, namely 2α-OHT, 2β-OHT, 6α-OHT, 6β-OHT, 7α-OHT and 16α-OHT, could be sufficiently separated
from each other and thus an unequivocal assignment to the individual structures was achieved. Validation data are presented
specifying the limits of quantitation as well as the mean values of the coefficients of variation (CV) for the target analytes
and the accuracy obtained at five different days. Regio- and stereoselective testosterone hydroxylation by rat hepatocytes
was measured in a long-term culture system with and without exposure to rifampicin as an inducer of liver CYP 3A4 activity.
In addition, testosterone hydroxylation was analyzed in cultures of cryopreserved hepatocytes that had been stored at −196 °C.
The rat hepatocytes were cultured after thawing for up to 11 days and induction of testosterone hydroxylase activity could
be demonstrated in cultures which underwent a new cryopreservation protocol.
This paper is dedicated to Professor Hinrich Cramer on the occasion of his 75th birthday. 相似文献
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Steinberg B.D. Carlson D.L. Lee W. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1989,77(5):663-669
Localized RCS measurements are presented for the Boeing 727 and the Lockheed L-1011 aircraft. The measurements were made at X-band from a few degrees aft of broadside. The elevation angle was approximately 30°. Four data sets, each of 128 pulses, were obtained from each airplane examined. The data presented are composites of measurements of five Boeing 727s and three L-1011s 相似文献
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L. H. Rogers G. W. Standen L. Kovach R. A. Steinberg und A. J. Lindsey 《Fresenius' Journal of Analytical Chemistry》1943,126(2):76-79
Ohne Zusammenfassung 相似文献
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