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1. This communication reports the action of bovine thrombin on ovine, bovine and human growth hormones. Thrombin cleavage was shown to be restricted to a single homologous peptide bond in all three growth hormones (at sequence positions 133--134 of the ovine and bovine hormones). 2. Ovine growth hormone was the most sensitive to the action of thrombin, bovine growth hormone was attacked to a relatively less extent, and human growth hormone was the most resistant to the enzyme. 3. After reduction and carbamidomethylation of the disulfide bonds in thrombin modified ovine growth hormone, the two fragments (residues 1--133 and 134--191) were isolated. The large NH2-terminal thrombin fragment of the hormone (residues 1--133) was found to be inactive in the rat tibia test, whereas a tryptic fragment (residues 96--133) isolated in an independent way gave measurable responses. 相似文献
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Zusammenfassung An zwei Stämmen Azotobacter chroococcum Beij. wurden in Montmorillonit als Bodenmodell Atmungsmessungen unter Röntgenbestrahlung durchgeführt. Durch die Bestrahlung wurde bei beiden Stämmen die Atmungsintensität erniedrigt. Aus dem Beginn der Atmungsdepression nach Einsetzen der Bestrahlung lassen sich Rückschlüsse auf die Strahlenresistenz der verschiedenen Stämme ziehen. Die Strahlenresistenz der beiden untersuchten Bakterien-Stämme war im Montmorillonit im Vergleich zu Suspensionen wesentlich erhöht. 相似文献
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Hermann Cuntz Friedrich Forstner Bettina Schnell Georg Ammer Shamprasad Varija Raghu Alexander Borst 《PloS one》2013,8(8)
Important brain functions need to be conserved throughout organisms of extremely varying sizes. Here we study the scaling properties of an essential component of computation in the brain: the single neuron. We compare morphology and signal propagation of a uniquely identifiable interneuron, the HS cell, in the blowfly (Calliphora) with its exact counterpart in the fruit fly (Drosophila) which is about four times smaller in each dimension. Anatomical features of the HS cell scale isometrically and minimise wiring costs but, by themselves, do not scale to preserve the electrotonic behaviour. However, the membrane properties are set to conserve dendritic as well as axonal delays and attenuation as well as dendritic integration of visual information. In conclusion, the electrotonic structure of a neuron, the HS cell in this case, is surprisingly stable over a wide range of morphological scales. 相似文献
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Eliana Cordero Jan Rüger Dominik Marti Abdullah S. Mondol Thomas Hasselager Karin Mogensen Gregers G. Hermann Jürgen Popp Iwan W. Schie 《Journal of biophotonics》2020,13(2)
Existing approaches for early‐stage bladder tumor diagnosis largely depend on invasive and time‐consuming procedures, resulting in hospitalization, bleeding, bladder perforation, infection and other health risks for the patient. The reduction of current risk factors, while maintaining or even improving the diagnostic precision, is an underlying factor in clinical instrumentation research. For example, for clinic surveillance of patients with a history of noninvasive bladder tumors real‐time tumor diagnosis can enable immediate laser‐based removal of tumors using flexible cystoscopes in the outpatient clinic. Therefore, novel diagnostic modalities are required that can provide real‐time in vivo tumor diagnosis. Raman spectroscopy provides biochemical information of tissue samples ex vivo and in vivo and without the need for complicated sample preparation and staining procedures. For the past decade there has been a rise in applications to diagnose and characterize early cancer in different organs, such as in head and neck, colon and stomach, but also different pathologies, for example, inflammation and atherosclerotic plaques. Bladder pathology has also been studied but only with little attention to aspects that can influence the diagnosis, such as tissue heterogeneity, data preprocessing and model development. The present study presents a clinical investigative study on bladder biopsies to characterize the tumor grading ex vivo, using a compact fiber probe‐based imaging Raman system, as a crucial step towards in vivo Raman endoscopy. Furthermore, this study presents an evaluation of the tissue heterogeneity of highly fluorescent bladder tissues, and the multivariate statistical analysis for discrimination between nontumor tissue, and low‐ and high‐grade tumor. 相似文献
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Hermann Grote 《Journal of Ornithology》1923,71(2-3):366-369
Ohne Zusammenfassung 相似文献
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Hermann Desselberger 《Journal of Ornithology》1930,78(3):328-376
Ohne Zusammenfassung 相似文献
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