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531.
Carolin Curtze At L. Hof Helco G. van Keeken Jan P.K. Halbertsma Klaas Postema Bert Otten 《Journal of biomechanics》2009,42(11):1746-1753
A prosthetic foot is a key element of a prosthetic leg, literally forming the basis for a stable and efficient amputee gait. We determined the roll-over characteristics of a broad range of prosthetic feet and examined the effect of a variety of shoes on these characteristics. The body weight of a person acting on a prosthetic foot during roll-over was emulated by means of an inverted pendulum-like apparatus. Parameters measured were the effective radius of curvature, the forward travel of the center of pressure, and the instantaneous radius of curvature of the prosthetic feet. Finally, we discuss how these parameters relate to amputee gait. 相似文献
532.
Bruchpilot, a protein with homology to ELKS/CAST, is required for structural integrity and function of synaptic active zones in Drosophila 总被引:1,自引:0,他引:1
533.
Carolin Heggemann Carsten Budke Benjamin Schomburg Zsuzsa Majer Marco Wißbrock Thomas Koop Norbert Sewald 《Amino acids》2010,38(1):213-222
Antifreeze glycoproteins enable life at temperatures below the freezing point of physiological solutions. They usually consist
of the repetitive tripeptide unit (-Ala-Ala-Thr-) with the disaccharide α-d-galactosyl-(1–3)-β-N-acetyl-d-galactosamine attached to each hydroxyl group of threonine. Monoglycosylated analogues have been synthesized from the corresponding
monoglycosylated threonine building block by microwave-assisted solid phase peptide synthesis. This method allows the preparation
of analogues containing sequence variations which are not accessible by other synthetic methods. As antifreeze glycoproteins
consist of numerous isoforms they are difficult to obtain in pure form from natural sources. The synthetic peptides have been
structurally analyzed by CD and NMR spectroscopy in proton exchange experiments revealing a structure as flexible as reported
for the native peptides. Microphysical recrystallization tests show an ice structuring influence and ice growth inhibition
depending on the concentration, chain length and sequence of the peptides. 相似文献
534.
Lau C Borgmann S Maciejewska M Ngounou B Gründler P Schuhmann W 《Biosensors & bioelectronics》2007,22(12):3014-3020
Indirectly heated electrodes operating in a non-isothermal mode have been used as transducers for reagentless glucose biosensors. Pyrroloquinoline quinone-dependent soluble glucose dehydrogenase (PQQ-sGDH) was entrapped on the electrode surface within a redox hydrogel layer. Localized polymer film precipitation was invoked by electrochemically modulating the pH-value in the diffusion zone in front of the electrode. The resulting decrease in solubility of an anodic electrodeposition paint (EDP) functionalized with Osmium complexes leads to precipitation of the redox hydrogel concomitantly entrapping the enzyme. The resulting sensor architecture enables a fast electron transfer between enzyme and electrode surface. The glucose sensor was operated at pre-defined temperatures using a multiple current-pulse mode allowing reproducible indirect heating of the sensor. The sensor characteristics such as the apparent Michaelis constants K(M)(app) and maximum currents I(max)(app) were determined at different temperatures for the main substrate glucose as well as a potential interfering co-substrate maltose. The limit of detection increased with higher temperatures for both substrates (0.020 mM for glucose, and 0.023 mM for maltose at 48 degrees C). The substrate specificity of PQQ-sGDH is highly temperature dependent. Therefore, a mathematical model based on a multiple linear regression approach could be applied to discriminate between the current response for glucose and maltose. This allowed accurate determination of glucose in a concentration range of 0-0.1mM in the presence of unknown maltose concentrations ranging from 0 to 0.04 mM. 相似文献
535.
536.
Carolin Maria Throm Georg Wiora Carina Reble Johannes Schleusener Sabine Schanzer Hans Karrer Ludger Kolbe Georg Khazaka Martina C. Meinke Jürgen Lademann 《Journal of biophotonics》2021,14(2):e202000348
The sun protection factor (SPF) values are currently determined using an invasive procedure, in which the volunteers are irradiated with ultraviolet (UV) light. Non-invasive approaches based on hybrid diffuse reflectance spectroscopy (HDRS) have shown a good correlation with conventional SPF testing. Here, we present a novel compact and adjustable DRS test system. The in vivo measurements were performed using a multi-lambda-LED light source and an 84-channel imaging spectrograph with a fiber optic probe for detection. A transmission spectrum was calculated based on the reflectance measured with sunscreen and the reflectance measured without sunscreen. The preexposure in vitro spectrum was fitted to the in vivo spectrum. Each of the 11 test products was investigated on 10 volunteers. The SPF and UVA-PF values obtained by this new approach were compared with in vivo SPF results determined by certified test institutes. A correlation coefficient R2 = 0.86 for SPF, and R2 = 0.92 for UVA-PF were calculated. Having examined various approaches to apply the HDRS principle, the method we present was found to produce valid and reproducible results, suggesting that the multi-lambda-LED device is suitable for in-vivo SPF testing based on the HDRS principle as well as for in-vivo UVA-PF measurements. 相似文献
537.
538.
Peter S Klosterman Andrew V Uzilov Yuri R Bendaña Robert K Bradley Sharon Chao Carolin Kosiol Nick Goldman Ian Holmes 《BMC bioinformatics》2006,7(1):428-25