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Summary The article surveys our knowledge of the normalizing factor, gained from its discovery a quarter of a century ago up to the present time, under the following headings: Discovery; Physiological properties; Isolation and characterization; Structure determination (Identity of the normalizing factor with nicotianamine); Chemical properties; Analysis; Synthesis; Occurrence and physiological role; Related compounds; Prospects. 相似文献
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Felis T Lohmann G Kuhnert H Lorenz SJ Scholz D Pätzold J Al-Rousan SA Al-Moghrabi SM 《Nature》2004,429(6988):164-168
The last interglacial period (about 125,000 years ago) is thought to have been at least as warm as the present climate. Owing to changes in the Earth's orbit around the Sun, it is thought that insolation in the Northern Hemisphere varied more strongly than today on seasonal timescales, which would have led to corresponding changes in the seasonal temperature cycle. Here we present seasonally resolved proxy records using corals from the northernmost Red Sea, which record climate during the last interglacial period, the late Holocene epoch and the present. We find an increased seasonality in the temperature recorded in the last interglacial coral. Today, climate in the northern Red Sea is sensitive to the North Atlantic Oscillation, a climate oscillation that strongly influences winter temperatures and precipitation in the North Atlantic region. From our coral records and simulations with a coupled atmosphere-ocean circulation model, we conclude that a tendency towards the high-index state of the North Atlantic Oscillation during the last interglacial period, which is consistent with European proxy records, contributed to the larger amplitude of the seasonal cycle in the Middle East. 相似文献
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The phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) mimicked the effects of isoprenaline on the force of contraction, the cAMP content and the slow Ca++ inward current (Isi) in isolated guinea pig papillary muscles. The results support the hypothesis that phosphodiesterase inhibitors and beta-adrenoceptor agonists exert their positive inotropic effects by increasing Isi via the common mediator cAMP. 相似文献
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Role of erythropoietin in adaptation to hypoxia 总被引:3,自引:0,他引:3
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Jakobsson M Scholz SW Scheet P Gibbs JR VanLiere JM Fung HC Szpiech ZA Degnan JH Wang K Guerreiro R Bras JM Schymick JC Hernandez DG Traynor BJ Simon-Sanchez J Matarin M Britton A van de Leemput J Rafferty I Bucan M Cann HM Hardy JA Rosenberg NA Singleton AB 《Nature》2008,451(7181):998-1003
Genome-wide patterns of variation across individuals provide a powerful source of data for uncovering the history of migration, range expansion, and adaptation of the human species. However, high-resolution surveys of variation in genotype, haplotype and copy number have generally focused on a small number of population groups. Here we report the analysis of high-quality genotypes at 525,910 single-nucleotide polymorphisms (SNPs) and 396 copy-number-variable loci in a worldwide sample of 29 populations. Analysis of SNP genotypes yields strongly supported fine-scale inferences about population structure. Increasing linkage disequilibrium is observed with increasing geographic distance from Africa, as expected under a serial founder effect for the out-of-Africa spread of human populations. New approaches for haplotype analysis produce inferences about population structure that complement results based on unphased SNPs. Despite a difference from SNPs in the frequency spectrum of the copy-number variants (CNVs) detected--including a comparatively large number of CNVs in previously unexamined populations from Oceania and the Americas--the global distribution of CNVs largely accords with population structure analyses for SNP data sets of similar size. Our results produce new inferences about inter-population variation, support the utility of CNVs in human population-genetic research, and serve as a genomic resource for human-genetic studies in diverse worldwide populations. 相似文献
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R. Brückner S. Gramann M. Nose W. Schmitz H. Scholz 《Cellular and molecular life sciences : CMLS》1985,41(6):732-734
Summary The phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) mimicked the effects of isoprenaline on the force of contraction, the cAMP content and the slow Ca++ inward current (Isi) in isolated guinea pig papillary muscles. The results support the hypothesis that phosphodiesterase inhibitors and -adrenoceptor agonists exert their positive inotropic effects by increasing Isi via the common mediator cAMP.Acknowledgment. This work was supported by the Deutsche Forschungsgemeinschaft. 相似文献
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Analytic and Dynamic Approach to Collaboration: A Transdisciplinary Case Study on Sustainable Landscape Development in a Swiss Prealpine Region 总被引:1,自引:0,他引:1
Michael Stauffacher Thomas Flüeler Pius Krütli Roland W. Scholz 《Systemic Practice and Action Research》2008,21(6):409-422
The involvement of stakeholders and the public in societal decision processes has lately received increased attention. We
suggest that appropriate and tailored techniques should be selected and integrated to provide the prerequisites for inclusive
involvement depending on the issue, type, goals and phase of the decision process in question, i.e. an analytic, systematic
and dynamic approach to collaboration. In a transdisciplinary case study design we integrate diverse analytical methods whereby
a process of mutual learning between science and people from outside academia is strived for. Our framework for collaboration
is illustrated by a case study on sustainable landscape development in the Swiss prealpine region of Appenzell Ausserrhoden.
相似文献
Michael StauffacherEmail: |
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H. Scholz 《Cellular and molecular life sciences : CMLS》1970,26(8):864-866
Summary In isolated, electrically driven, left guineapig atria, theophylline (5×10–4 g/ml) increased the rate of45Ca uptake and release without affecting the total myocardial Ca content and the amount of exchangeable cellular Ca. In sheep and calf heart preparations, theophylline (10–4–10–3 g/ml) increased Ca inward current during excitation (as examined indirectly by Ca dependent changes of membrane potential in TTX-containing solutions) as well as tension development. It is concluded that the positive inotropic effect of theophylline in mammalian hearts is due to an increase in Ca influx during the excitation process.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献