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971.
Schmidt HL Rossmann A Voerkelius S Schnitzler WH Georgi M Grassmann J Zimmermann G Winkler R 《Isotopes in environmental and health studies》2005,41(3):223-228
Multielement isotope ratio analysis was checked for its suitability as a means for the discrimination between agricultural products from integrated/conventional or organic production, respectively. Differences were mainly found for delta15N-values. Paprika and tomatoes from organic production in greenhouses showed delta15N-values above+7 per thousand, whereas corresponding products from conventional cultivation had delta15N-values near 0 per thousand. Lettuce, onions, cabbage and Chinese cabbage from field production had delta15N-values in the range of+5 to+6 and+5.5 to+7.5 per thousand, respectively (conventional and organic production); these overlapping differences do not permit a reliable discrimination. The same is true for wheat, showing average delta15N-values of+2.3+/-1.0 and+3.6+/-1.6 per thousand, respectively. The unexpected relative high 15N-enrichments of vegetables from integrated production are discussed as originating, at least partially, from 15N-enrichment in the soil by NH3 evaporation and denitrification. 相似文献
972.
Andersen ML Ruhwald M Thorn M Pedersen AE Mathiassen S Buus S Claesson MH 《Journal of immune based therapies and vaccines》2003,1(1):1
Thirteen H-2b-binding peptides derived from six potentially overexpressed proteins in p53-/- thymoma (SM7) cells were studied for immunogenecity and vaccine-induced prevention of tumor growth in mice inoculated with SM7 tumor cells. Six of the peptides generated specific CTL responses after immunization, but only two of these peptides (RAD23-31 and RAD24-31) were capable of generating a weak vaccination-induced protection against adoptive tumor growth. SM7 inoculated mice treated with a blocking antibody against the inhibitory T cell signal transducing molecule CTLA4 appeared to delay tumor take, suggesting that SM7 thymoma cells are recognized by the adaptive immune system of the host. However, prophylactic vaccination with RAD23-31 and RAD24-31 peptides combined with anti-CTLA4 Ab treatment and did not improve tumor resistance. Our data would indicate that vaccination with immunogenic peptides derived from potentially overexpressed tumor proteins, as identified by mRNA expression profiling of p53-/- thymoma cells, at best results in a weak tumor protection thus questioning this way of detection of new tumor rejection epitopes. 相似文献
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977.
Susanne Beer 《manuscripta mathematica》1969,1(2):201-209
Let k be a field which is locally compact with respect to a valuation ||, let X denote the subset X={ k, ||1}. This paper is concerned with sequences of elements of X with respect to the theory of uniform distribution. Let DN() denote the discrepancy of the sequence =(xn). It is proved that for archimedian valuations with a certain constant for every sequence . In the non-archimedian case there exist sequences with
. 相似文献
978.
Ohne Zusammenfassung
Determination of platinum and biological trace elements in efficiency studies on pt-containing cancer drugs by activation analysis相似文献
979.
Susanne C. Brenner 《Numerische Mathematik》1996,72(4):419-447
Summary.
A two-level additive Schwarz preconditioner is
developed for the
systems resulting from the discretizations of
the plate bending problem by the Morley finite element, the
Fraeijs de Veubeke finite element, the Zienkiewicz finite
element and the Adini
finite element. The condition numbers of the preconditioned
systems are shown
to be bounded independent of mesh sizes and the number of
subdomains in the
case of a generous overlap.
Received
February 1, 1994 / Revised version received October 24, 1994 相似文献
980.
Susanne Danz 《代数通讯》2013,41(12):4521-4539