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81.
Heiner Gorrissen Alexander P. Tulloch Robert J. Cushley 《Chemistry and physics of lipids》1982,31(3):245-255
Aqueous dispersions of egg-phosphatidylcholine and egg-phosphatidylcholine/30 mol% cholesterol containing deuterated tripalmitin or triolein were studied at approx. 25°C by 2H-NMR. Incorporation of tripalmitin into egg-phosphatidylcholine bilayers was found to be less than 0.1 mol%, while the incorporation of trolein is approx. 2.5 mol% in the absence and approx. 0.7 mol% in the presence of cholesterol. The profile of order parameter versus chain position for deuterated triolein suggests that the oleoyl chains of the triacylglycerol have an average orientation such that the C2 chain segments and the segments in the vicinity of the C9–C10 double bond are tilted with respect to the bilayer normal, while all other segments are parallel to the bilayer normal. Longitudinal relaxation times were also determined and indicate that the acyl chains of triolein have a motional behaviour similar to that of phospholipid acyl chains in the bilayer. 相似文献
82.
83.
84.
Ulrike Willeke Volker Heeger Maria Meise Heiner Neuhann Ingrid Schindelmeiser Karin Vordemfelde Wolfgang Barz 《Phytochemistry》1979,18(1):105-110
In 50 cell suspension cultures of wide taxonomic origin, formation of trigonelline and nicotinic acid N-α-l-arabinoside from nicotinate was strictly alternative. The arabinoside was only found in cell cultures of the subclass Asteridae and in the higher orders of the subclasses Rosidae and Dilleniidae. Degradation of nicotinic acid could only be observed in cell cultures producing the arabinoside. Nicotinic acid degradation does not involve free 6-hydroxynicotinic acid. Cross feeding experiments with both conjugates and measurements of a nicotinic acid N-arabinoside: UDP-arabinosyltransferase support the hypothesis that metabolism of these two derivatives in cell cultures may be of chemosystematic value. Finally various discrepancies between plants and cell cultures with respect to nicotinate metabolism and to the natural occurrence of the two conjugates are discussed. 相似文献
85.
86.
Heiner Lehmann 《Plant biology (Stuttgart, Germany)》1971,84(10):615-627
In wachsenden Kulturen der blaugrünen Alge Microcystis aeruginosa nimmt die Anzahl der Gasvakuolen pro Zelle ab und erreicht bei einer Zellzahl von 1,2 × 107 pro ml eine Zahl von 4,5 × 103 Vakuolen pro Zelle. Die Gasvakuolen können in den Zellen durch Ultraschall zerstört werden, danach regenerieren sie. In beschallten Kulturen wurde die Zeitabhängigkeit der Gasvakuolenbildung untersucht, indem die Anzahl und die Größe der neugebildeten Vakuolen bestimmt wurde. Innerhalb der ersten halben Stunde nach Ultraschallbehandlung werden 120 Gasvakuolen pro Zelle gebildet, nach 24 Stunden enthält jede Zelle durchschnittlich 2300 Vakuolen. Die Größe der Gasvakuolen nimmt ebenfalls mit der Zeit zu. In der ersten halben Stunde erreichen die bis dahin isodiametrischen Vakuolen eine Größe von 70 nm, dann wachsen sie nur noch in die Länge und haben 24 Stunden nach Ultraschallbehandlung eine durchschnittliche Länge von 286 nm. Rifampin und Chloramphenicol bewirken eine teilweise Hemmung der Gasvakuolenbildung. DCMU und Hydroxylamin blockieren die Vakuolenbildung völlig. Auch im Dunkeln werden keine Gasvakuolen gebildet 相似文献
87.
mRNA extracted from polysomes of KB cells at late stages of productive infection with adenovirus type 2 was translated in a cell-free system derived from Krebs II ascites cells. Two of the polypeptides obtained in this reaction corresponded to the adenovirus core protein V and the precursor to core protein VII. The following criteria were used to establish identity between the in vitro products and the virion proteins: comigration during sodium dodecyl sulfatepolyacrylamide gel electrophoresis, cochromatography in sodium dodecyl sulfate-hydroxyapatite, specific immunoprecipitation of the precursor to core protein VII, and tryptic peptide analysis. 相似文献
88.
Wiebke Garrels Ayan Mukherjee Stephanie Holler Nicole Cleve Thirumala R. Talluri Brigitte Barg-Kues Mike Diederich Peter Köhler Björn Petersen Andrea Lucas-Hahn Heiner Niemann Zsuzsanna Izsvák Zoltán Ivics Wilfried A. Kues 《Transgenic research》2016,25(1):63-70
Recently, we established the Sleeping Beauty transposon system for germ line competent transgenesis in the pig. Here, we extend this approach to re-target a transposon-tagged locus for a site-specific gene knock-in, and generated a syngeneic cohort of piglets carrying either the original transposon or the re-targeted event. A Cre-loxP-mediated cassette exchange of the tagging transposon with a different reporter gene was performed, followed by flow cytometric sorting and somatic cell nuclear transfer of recombined cells. In parallel, the original cells were employed in somatic cell nuclear transfer to generate clone siblings, thereby resulting in a clone cohort of piglets carrying different reporter transposons at an identical chromosomal location. Importantly, this strategy supersedes the need for an antibiotic selection marker. This approach expands the arsenal of genome engineering technologies in domestic animals, and will facilitate the development of large animal models for human diseases. Potentially, the syngeneic cohort of pigs will be instrumental for vital tracking of transplanted cells in pre-clinical assessments of novel cell therapies. 相似文献
89.
Authors index 总被引:1,自引:0,他引:1
Lehmann Johannes Weigl Doris Peter Inka Droppelmann Klaus Gebauer Gerhard Goldbach Heiner Zech Wolfgang 《Plant and Soil》1999,210(2):249-262
In a runoff irrigation system in Northern Kenya, we studied the nutrient interactions of sole cropped and alley cropped Sorghum
bicolor (L.) Moench and Acacia saligna (Labill.) H.L. Wendl. The trees were pruned once before the cropping season and the
biomass was used as fodder for animals. The nutrient contents in leaf tissue, soil and soil solution were monitored and the
uptake of applied tracers (15N, Sr) was followed. The grain yield of alley cropped sorghum was similar to or slightly higher than in monoculture and did
not decrease near the tree-crop interface. Foliar N and Ca contents of the crop were higher in the agroforestry combination
than in monoculture, corresponding to higher soil N and Ca contents. Soil solution and soil mineral N dynamics indicate an
increase of N under the tree row and unused soil N at the topsoil in the alley of the sole cropped trees as well as below
60 cm depth in the crop monoculture. The N use efficiency of the tree+crop combination was higher than the sole cropped trees
or crops. Competition was observed for Zn and Mn of both tree and crop whereas for Ca only the tree contents decreased. P,
K, Mg and Fe dynamics were not affected by alley cropping at our site. The lower uptake of applied Sr by trees in alley cropping
compared to those of the monoculture stand suggested a lower competitiveness of the acacia than sorghum, which did not show
lower Sr contents when intercropped. The study showed the usefulness of combining soil and plant analyses together with tracer
techniques identifying nutrient competition, nutrient transfer processes and the complementary use of soil nutrients, as the
main features of the tree-crop combination.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
90.
Priya A. Debisarun Katharina L. Gssling Ozlem Bulut Gizem Kilic Martijn Zoodsma Zhaoli Liu Marina Oldenburg Nadine Rüchel Bowen Zhang Cheng-Jian Xu Patrick Struycken Valerie A. C. M. Koeken Jorge Domínguez-Andrs Simone J. C. F. M. Moorlag Esther Taks Philipp N. Ostermann Lisa Müller Heiner Schaal Ortwin Adams Arndt Borkhardt Jaap ten Oever Reinout van Crevel Yang Li Mihai G. Netea 《PLoS pathogens》2021,17(10)