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11.
Klaus Schmidt und Eberhard Hantge 《Journal of Ornithology》1954,95(1-2):130-173
Ohne ZusammenfassungMrs. Margaret M. Nice gewidmet zum 70. Geburtstag am 6. Dezember 1953In verkürzter Form vorgetragen vonK. Schmidt auf der 67. Tagung der D. O.-G. am 16. August 1953 in Köln. — 291. Ringfundmitteilung der Vogelwarte Radolfzell. 相似文献
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Siegfried Huneck Klaus Schreiber Hans Dieter Grimmecke 《Journal of Plant Growth Regulation》1984,3(1-3):75-84
Seventy-two Schiffs bases, 44 corresponding secondary amines, and 12 N-acetylated compounds were tested on their growth activity. Eighty-one compounds were active as growth inhibitors in at least one of three bioassays. 相似文献
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Spinal muscular atrophy (SMA) is the most common genetic disease that causes infant mortality. Its treatment and prevention represent the paradigmatic example of the ethical dilemmas of 21st-century medicine. New therapies (nusinersen and AVXS-101) hold the promise of being able to treat, but not cure, the condition. Alternatively, genomic analysis could identify carriers, and carriers could be offered in vitro fertilization and preimplantation genetic diagnosis. In the future, gene editing could prevent the condition at the embryonic stage. How should these different options be evaluated and compared within a health system? In this paper, we discuss the ethical considerations that bear on the question of how to prioritize the different treatments and preventive options for SMA, at a policy level. We argue that despite the tremendous value of what we call ‘ex-post’ approaches to treating SMA (such as using pharmacological agents or gene therapy), there is a moral imperative to pursue ‘ex-ante’ interventions (such as carrier screening in combination with prenatal testing and preimplantation genetic diagnosis, or gene editing) to reduce the incidence of SMA. There are moral reasons relating to autonomy, beneficence and justice to prioritize ex-ante methods over ex-post methods. 相似文献
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Klaus Napp-Zinn 《Plant Systematics and Evolution》1951,98(1-2):142-170
Ohne Zusammenfassung 相似文献
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The polypeptide composition of the large and small subunits of Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase) from Arabidopsis thaliana, A. suecica and Cardaminopsis arenosa have been studied by IEF (isoelectric focusing) analysis. The putative recent alopolyploid origin of A. suecica is supported. The chloroplast encoded large subunits served to identify solely A. thaliana as the maternal parent whereas the nuclear encoded small subunits indicate C. arenosa as the paternal species. 相似文献
19.
The inactivation of Bacillus subtilis spores during long-term exposure (up to several months) to extreme dryness (especially vacuum) is strain-dependent, through only to a small degree. During a first phase (lasting about four days) monolayers of spores lose about 20% of their viability, regardless of the strain studied. During this phase loss in viability can be equally attributed both to damages of hydrophobic structures (membranes and proteins) and DNA. During a second phase lasting for the remaining time of experimental observation (weeks, months and years) the loss in viability is slowed. A viability of 55% to 75% (depending on the strain) is attained after a total exposure of 36 days. The loss in viability during the second phase can be correlated with the occurrence of DNA double strand breaks. Also covalent DNA-protein cross-links are formed by vacuum exposure. If the protein moiety of these cross-links is degraded by proteinase K-treatment in vitro additional DNA double strand breaks result. The data are also discussed with respect to survival on Mars and in near Earth orbits. 相似文献