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1.
Summary As shown in preceding papers of the authors, the verification of anR-convergence order for sequences coupled by a system (1.1) of basic inequalities can be reduced to the positive solvability of system (3.3) of linear inequalities. Further, the bestR-order implied by (1.1) is equal to the minimal spectral radius of certain matrices composed from the exponents occuring in (1.1). Now, these results are proven in a unified and essentially simpler way. Moreover, they are somewhat extended in order to facilitate applications to concrete methods.  相似文献   
2.
Mirror-image oligonucleotide ligands (Spiegelmers) that bind to the pharmacologically relevant target gonadotropin-releasing hormone I (GnRH) with high affinity and high specificity have been identified using the Spiegelmer technology. GnRH is a decapeptide that plays an important role in mammalian reproduction and sexual maturation and is associated with several benign and malignant diseases. First, aptamers that bind to D-GnRH with dissociation constants of 50-100 nM were isolated out of RNA and DNA libraries. The respective enantiomers of the DNA and RNA aptamers were synthesized, and their binding to L-GnRH was shown. These Spiegelmers bind to L-GnRH with similar affinity to that of the corresponding aptamers that bind to D-GnRH. We further demonstrated dose-dependent inhibition of GnRH-induced Ca(2+) release in Chinese hamster ovary cells that were stably transfected with the human GnRH receptor.  相似文献   
3.
Zusammenfassung Es wird beschrieben, wie man unter Anwendung von radioaktiven Stoffen kinetische Untersuchungen an der Wackenroderschen Reaktion durchführen kann. Dabei geht man nach einer papierchromatographischen Methode zur Trennung von Polythionsäuren vor, indem man durch laufende Probenentnahme während des Reaktionsablaufes die jeweilige Zusammensetzung der Wackenroderschen Flüssigkeit festhält. Die auf diese Weise gewonnenen Papierchromatogramme werden durch einen Radiopapierchromatographen ausgewertet. Die Verfolgung der einzelnen Stadien dieses Prozesses ist nur möglich, weil es sich bei der Wackenroderschen Reaktion hauptsächlich um langsame Vorgänge nach Art der Verseifungsprozesse handelt und dürfte daher mit Erfolg auf analoge Systeme zu übertragen sein.  相似文献   
4.
The femtosecond dissociation of HCl after core excitation has been studied through the resonant Auger decay. The spectra contain contributions from decay occurring at both "molecular" and "atomic" internuclear distances. We have observed a new interference mechanism in these spectra: An atomic spectral line develops into a negative spectral contribution, a "hole," when detuning the excitation energy from the maximum of the Cl2p(-1)sigma(*) resonance. Resonant x-ray scattering theory quantitatively explains this behavior as due to a novel destructive continuum-continuum interference between molecular and atomic contributions to the Auger decay.  相似文献   
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New results are presented of an analysis of pictures taken during an exposure of Gargamelle to the CERN ν beam in 1975. In addition to three νμ+N→μ?+e++V0+ hadrons events previously reported, an excess is found of events of the type νμ+N→μ?+e++ hadrons without V0. An analysis of strange particle production in charged current events suggests a possible violation of the ΔS=ΔQ rule. Interpreted in terms of charm production, the data permit an estimate of branching ratios and production rate of charmed particles. A limit is also placed on charmed particle production by neutral currents.  相似文献   
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Using the Monte-Carlo-Method linear electron-photon showers in lead have been calculated for primary electron and photon energies of 100, 200 and 380 MeV. We find that, beyond the maximum, the slope of the shower curves depends on the primary energy as well as on the cut-off energy of the electron and photon spectra. This behaviour is in agreement with recent experimental data.  相似文献   
10.
A series of ruthenium(II) complexes with N-heterocyclic carbene (NHC) ligands of the general type (arene)(NHC)Ru(II)X2 (where X = halide) was prepared, characterized, and evaluated as antibacterial agents in comparison to the respective metal free benzimidazolium cations. The ruthenium(II) NHC complexes generally triggered stronger bacterial growth inhibition than the metal free benzimidazolium cations. The effects were much stronger against Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) than against Gram-negative bacteria (Escherichia coli, Acinetobacter baumannii, Pseudomonas aeruginosa), and all complexes were inactive against the fungus Candida albicans. Moderate inhibition of bacterial thioredoxin reductase was confirmed for selected complexes, indicating that inhibition of this enzyme might be a contributing factor to the antibacterial effects.  相似文献   
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