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81.
Incorporation of isolated chromosomes and induction of hypoxanthine phosphoribosyltransferase in Chinese hamster cells. 总被引:1,自引:0,他引:1
Evidence is presented for the uptake of radioactive-labeled isolated Chinese hamster chromosomes following incubation with Chinese hamster cells. Metaphases were found which contained radioactive labeled chromosomes in a very low frequency, and in some of the labeled chromosomes only one chromatid was labeled. Incubation of hypoxanthine phosphoribosyltransferas (HPRT)-deficient Chinese hamster cells with chromosomes isolated from HPRT+ Chinese hamster or human cells resulted in the appearance of HPRT+ cells. Clones derived from these cells were isolated in HAT medium. Cells in mitosis during incubation with the chromosomes yielded thr-e times more HPRT+ clones than did cells in interphase. The intraspecies combination involving recipient cells and chromosomes from Chinese hamster origin yielded significantly higher numbers of HPRT+ clones than did the interspecies system using human chromsomes and Chinese hamster recipient cells (5 X 10(-5) and 6 X 10(-6) respectively). Electrophoresis of HPRT from Chinese hamster cells treated with human chromosomes revealed the pattern of the human enzyme. 相似文献
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Heidi Hrabetz Horst Thiermann Norbert Felgenhauer Thomas Zilker Bernhard Haller Jörg Nährig Bernd Saugel Florian Eyer 《Chemico-biological interactions》2013
Organophosphate (OP) poisoning is still associated with high morbidity and mortality rates, both in resource-poor settings and in well-developed countries. Despite numerous publications dealing with this particular poison, detailed clinical data on more severe overdoses with these agents are relatively sparsely reported. A retrospective study was consequently conducted on 33 patients with OP poisoning admitted to our intensive care unit (ICU) to provide additional data on clinical features. We included moderate to severe poisonings between 2000 and 2012 who required admission to ICU. 相似文献
84.
Isabel Rathmann Mona Frster Melih Yüksel Lucas Horst Gabriela Petrungaro Tobias Bollenbach Berenike Maier 《The ISME journal》2023,17(1):130
Bacterial transformation, a common mechanism of horizontal gene transfer, can speed up adaptive evolution. How its costs and benefits depend on the growth environment is poorly understood. Here, we characterize the distributions of fitness effects (DFE) of transformation in different conditions and test whether they predict in which condition transformation is beneficial. To determine the DFEs, we generate hybrid libraries between the recipient Bacillus subtilis and different donor species and measure the selection coefficient of each hybrid strain. In complex medium, the donor Bacillus vallismortis confers larger fitness effects than the more closely related donor Bacillus spizizenii. For both donors, the DFEs show strong effect beneficial transfers, indicating potential for fast adaptive evolution. While some transfers of B. vallismortis DNA show pleiotropic effects, various transfers are beneficial only under a single growth condition, indicating that the recipient can benefit from a variety of donor genes to adapt to varying growth conditions. We scrutinize the predictive value of the DFEs by laboratory evolution under different growth conditions and show that the DFEs correctly predict the condition at which transformation confers a benefit. We conclude that transformation has a strong potential for speeding up adaptation to varying environments by profiting from a gene pool shared between closely related species.Subject terms: Molecular evolution, Bacterial genetics 相似文献
85.
Ohne ZusammenfassungMit 4 Textabbildungen 相似文献
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88.
Ulrich Horst 《Pal?ontologische Zeitschrift》1961,35(3-4):235-241
89.
Horst Tiemann 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1960,30(5):202-205
Zusammenfassung Zur Genomverdoppelung bei Gramineen wurden vergleichsweise verschiedene Methoden angewandt. Die Colchicinmethoden ergaben einen größeren Anteil polyploider Pflanzen als die mit Acenaphthen.Mit 7 Abbildungen 相似文献
90.
Horst Drawert 《Protoplasma》1938,29(1):206-227
Ohne Zusammenfassung 相似文献