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91.
Martin Heller Anett Stcker Rudolf Kawalla Nora Leuning Kay Hameyer Xuefei Wei Gerhard Hirt Lucas Bhm Wolfram Volk Sandra Korte-Kerzel 《Materials》2022,15(1)
Non-oriented (NO) electrical steel sheets find their application in rotating electrical machines, ranging from generators for wind turbines to motors for the transportation sector and small motors for kitchen appliances. With the current trend of moving away from fossil fuel-based energy conversion towards an electricity-based one, these machines become more and more important and, as a consequence, the leverage effect in saving energy by improving efficiency is huge. It is already well established that different applications of an electrical machine have individual requirements for the properties of the NO electrical steel sheets, which in turn result from the microstructures and textures thereof. However, designing and producing tailor-made NO electrical steel sheet is still challenging, because the complex interdependence between processing steps, the different phenomena taking place and the resulting material properties are still not sufficiently understood. This work shows how established, as well as advanced and newly developed characterization methods, can be used to unfold these intricate connections. In this context, the respective characterization methods are explained and applied to NO electrical steel as well as to the typical processing steps. In addition, several experimental results are reviewed to show the strengths of the different methods, as well as their (dis)advantages, typical applications and obtainable data. 相似文献
92.
Monika Günther Hans-Dieter Haubeck Eddy Van De Leur Jrg Blser Sven Bender Ines Gütgemann Dagmar-Christiane Fischer Harald Tschesche Helmut Greiling Peter C. Heinrich Lutz Graeve 《Arthritis \u0026amp; Rheumatology》1994,37(3):395-405
Objective. To investigate the role of interleukin-6 (IL-6) and transforming growth factor β1 (TGF β1) in the regulation of tissue inhibitor of metalloproteinases—1 (TIMP-1) synthesis in human articular chondrocytes. Methods. Articular cartilage was obtained from human knee joints 24 hours after death. Chondrocytes were isolated by collagenase digestion and embedded in low-gelling-temperature agarose. After stimulation by cytokines, total RNA was isolated and analyzed by Northern blotting. TIMP-1 protein levels were determined using a competitive enzyme-linked immunosorbent assay. Results. Human chondrocytes in agarose culture expressed messenger RNA (mRNA) for the IL-6 receptor (gp80) and its signal-transducing subunit gp130. In contrast to the findings in a previous study, IL-6 did not stimulate TIMP-1 expression in these cells, whereas TGF β1 was an important inducer of TIMP-1 mRNA and protein synthesis. Conclusion. Our findings suggest that TGF β1 has a protective effect on the extracellular matrix of human articular chondrocytes. 相似文献
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Leila Amini Dimitrios Laurin Wagner Uta Rössler Ghazaleh Zarrinrad Livia Felicitas Wagner Tino Vollmer Désirée Jacqueline Wendering Uwe Kornak Hans-Dieter Volk Petra Reinke Michael Schmueck-Henneresse 《Molecular therapy》2021,29(1):32-46
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96.
Neuronal expression of the drug efflux transporter P-glycoprotein in the rat hippocampus after limbic seizures 总被引:16,自引:0,他引:16
In the brain, the efflux transporter P-glycoprotein (Pgp) is predominantly located on the luminal membrane of endothelial cells lining brain microvessels and forming the blood-brain barrier. Many lipophilic drugs, including antiepileptic drugs, are potential substrates for Pgp. Overexpression of Pgp in endothelial cells of the blood-brain barrier has been determined in patients with drug resistant forms of epilepsy such as temporal lobe epilepsy and rodent models of temporal lobe epilepsy and suggested to lead to reduced penetration of antiepileptic drugs into the brain. Expression of Pgp after seizures has also been described in astrocytes, whereas it is not clear whether neurons can express Pgp. In the present study, Pgp expression was studied by immunohistochemistry in rats 24 h after a status epilepticus induced by either pilocarpine or kainate, widely used models of temporal lobe epilepsy. Unexpectedly, in addition to endothelial Pgp staining, intense Pgp staining was found in neurons in the CA3c/CA4 sectors and hilus of the hippocampus formation, but not in other brain regions examined. The neuronal Pgp staining was confirmed by two different Pgp antibodies. Double immunolabeling and confocal microscopy showed that Pgp was colocalized with the neuronal marker neuronal nuclear antigen, but not with the glial marker glial fibrillary acidic protein. No neuronal Pgp staining was seen in control rats. The expression of Pgp in neurons after limbic seizures was substantiated by determining Pgp encoding genes (mdr1a, mdr1b) in neurons by real time quantitative RT-PCR. Increased Pgp expression in hippocampal neurons is likely to affect the action of drugs with intraneuronal targets and, in view of recent evidence from other cell types, could be associated with prevention of apoptosis which is involved in neuronal damage developing after seizures such as produced by pilocarpine. 相似文献
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The use of 3D surface imaging technology is becoming increasingly common in craniofacial clinics and research centers. Due to fast capture speeds and ease of use, 3D digital stereophotogrammetry is quickly becoming the preferred facial surface imaging modality. These systems can serve as an unparalleled tool for craniofacial surgeons, proving an objective digital archive of the patient's face without exposure to radiation. Acquiring consistent high-quality 3D facial captures requires planning and knowledge of the limitations of these devices. Currently, there are few resources available to help new users of this technology with the challenges they will inevitably confront. To address this deficit, this report will highlight a number of common issues that can interfere with the 3D capture process and offer practical solutions to optimize image quality. 相似文献