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701.
The human monoclonal antibody MH-4H7 recognizes the lipopolysaccharide outer core region of some Pseudomonas aeruginosa strains and in of some Pseudomonas aeruginosa strains and in particular strongly binds to strains of Lányi serotype 04. In this paper, we report that this monoclonal antibody also reacts with Escherichia coli O26 LPS. However, our results suggest that the previous reported immunological cross reaction between P. aeruginosa 04 and E. coli O26 strains (which was observed by using antisera against heat-stable antigens) is not due to the similarity of the O-polysaccharides. 相似文献
702.
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705.
Sandrine Mathieu Jérémie Wirth François-Xavier Sauvage Jean-Paul Lepoutre Raymond Baumes Ziya Gunata 《Plant Cell, Tissue and Organ Culture》2009,97(2):203-213
A cell suspension culture of cv. Gamay was studied for its ability to metabolize two different C13-norisoprenoidic volatiles, β-ionone and dehydrovomifoliol, together with monoterpenes, geraniol and linalool, biogenetically
common pathways sharing compounds. β-Ionone was totally metabolized leading to fourteen norisoprenoidic volatiles oxygenated
mainly at carbons 3 or 4 of the cyclohexane ring or reduced at side chain. The biotransformation of dehydrovomifoliol was
at a lesser extent, giving rise to oxygenated and reduced derivatives. The norisoprenoidic metabolites were present both under
free and glycosylated forms. Geraniol and linalool were also metabolized, leading to several free and glycosylated compounds.
S. Mathieu, J. Wirth contributed equally to the work and should be considered joint first authors.
A short part of this paper was published at the proceedings of the 10th Weurman Flavour Research Symposium, Flavour Research
at the Dawn of the Twenty-first Century, J.-L.Le Quere, P.-X.Etievant, Editors; Lavoisier,2003/Intercept Ltd, 2003. 相似文献
706.
M. Sezik O. Ozkaya E. Arslanoglu A. Koker H. Cetin D. Ozbasar H. Kaya 《Journal of Experimental Animal Science》2007,43(4):301-307
We aimed to evaluate the effects of intra-amniotic surfactant administration on alveolar lecithin/sphingomyelin ratio, density of type II pneumocytes, and fetal lung function in preterm merino sheep. Pregnant ewes at 119 days gestation either received 200 mg intra-amniotic surfactant (n=4) or saline solution (n=4). After 24 h, the lambs were delivered by hysterotomy and mechanically ventilated. Lecithin/sphingomyelin ratios in alveolar fluid, inflating pressure–volume relationships, and type II pneumocyte counts in histological specimens were compared among the groups. All of the lambs completed the protocol. Mean lecithin/sphingomyelin ratio increased significantly in amniotic (p=0.03) and alveolar fluid (p=0.03) samples of surfactant-treated animals. Lung function in terms of pressure–volume curves did not differ between two groups. Type II pneumocyte density tended to be higher (p=0.057) after intra-amniotic surfactant administration. Single-dose treatment with intra-amniotic surfactant seems to improve amniotic and alveolar lecithin/sphingomyelin ratio questionably by increasing alveolar type II cells. Pressure–volume relationships from inflation of the lungs might be unaltered with intra-amniotic surfactant treatment. 相似文献
707.
708.
Doubled haploid plant production from unpollinated ovules of sugar beet (Beta vulgaris L.) 总被引:2,自引:0,他引:2
The effects of cold pretreatment, AgNO3 and activated charcoal on haploid plant production from unpollinated sugar beet ovules were investigated. Both cold pretreatment
and the addition of charcoal increased the frequency of embryo formation, whereas AgNO3 decreased or completely inhibited it. Colchicine (50, 100, 150 or 500 mg l–1) and trifluralin (1.7, 3.4 or 5.0 mg l–1) for 12, 24, 36 or 48 h were compared in agar-solidified, agarose-solidified or liquid media. Although colchicine gave a
higher doubling rate (25.3%) than trifluralin (18.2%), the difference was not significant. Both agents were more effective
when used in liquid (29.1%) than agarose-solidified medium (20.7%) and agar-solidified medium (15.4%). A treatment duration
of 48 h was significantly more effective (27.5%) than 12 h (13.6%) but it was not different from 24 h (16.3%) or 36 h (18.6%).
Received: 25 October 1999 / Revision received: 18 May 2000 / Accepted: 29 May 2000 相似文献
709.
Z. Kaya M. M. Sewell D. B. Neale 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(3-4):586-592
Quantitative trait loci (QTLs) for annual height- and diameter-increment growth were estimated in each of two three-generation
loblolly pine pedigrees. Annual height-increment was measured in three consecutive years in the BASE pedigree and in four consecutive years in the QTL pedigree. Annual diameter-increment was measured only in the QTL pedigree for two consecutive years. An interval mapping-approach was used to estimate the number of QTLs, the magnitude of
QTL effects, and their position on genetic linkage maps. Thirteen different height-increment and eight different diameter-increment
QTLs were detected, suggesting that the these traits are, at least in part, controlled by a few genes of large effect. Little
evidence was found for the expression of individual QTLs in multiple years or in multiple genetic backgrounds. These results
were discussed in terms of the power of the experiment and their consequences for marker-assisted breeding.
Received: 12 July 1998/Accepted: 5 August 1998 相似文献
710.
A hydroxy fatty-acid-combined taurine (lipotaurine) was found in the taurolipids fraction of Tetrahymena thermophila. Lipotaurine accounted for about 1.4% of the total taurolipids of the cells, and was composed of taurine and 7,13-dihydroxy-2-trans-octadecenoic acid. By nuclear magnetic resonance, mass and infrared spectrometries, the chemical structure of lipotaurine was identified as 2-(7,13-dihydroxy-2-trans-octadecenoylamino)ethanesulfonic acid. When cells of T. thermophila were incubated with the double-labeled lipotaurine which was biosynthesized from [2(n)-3H]taurine and [1-14C]stearic acid, both the radioactivities were detected in taurolipid A, B and C. Furthermore, the ratio of the radioactivities of 3H and 14C in the lysotaurolipids were the same as that of the lipotaurine. From these results, it is suggested that lipotaurine is an intermediate of taurolipid biosynthesis. 相似文献