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排序方式: 共有1962条查询结果,搜索用时 15 毫秒
141.
142.
143.
Georg Hamel 《Forschung im Ingenieurwesen》1937,8(1):13-14
Zusammenfassung Im folgenden wird eine besondere L?sung der hydrodynamischen Gleichungen zusammendrückbarer Flüssigkeiten vorgelegt, die der
Str?mungsforschung vielleicht von Bedeutung sein dürfte.
VDI 相似文献
144.
Martin Gürtler Andreas Weddigen Georg Grathwohl 《Materialwissenschaft und Werkstofftechnik》1989,20(9):291-299
Mechanical testing of high-performance ceramics with tensile specimens Mechanical properties of engineering ceramics are often measured in bending. The principal limitations of these tests are discussed for linear-elastic and plastic material behaviour. From this the requirement of tensile tests is derived. For room temperature fatigue tests an optimized concept of gripping round specimens is presented. High temperature tests are performed with flat specimens allowing static and quasistatic experiments with continuous strain measurement up to ca. 1400 °C. For sintered silicon nitride tensile creep curves are reported and compared with results from bending tests. 相似文献
145.
MS Binding Assays are a label‐free alternative to radioligand binding assays. They provide basically the same capabilities as the latter, but an unlabeled reporter ligand is used instead of a radioligand. The study presented herein describes the development of MS Binding Assays that address D1 and D5 dopamine receptors. A highly sensitive, rapid and robust LC–ESI‐MS/MS quantification method for the selective D1 dopamine receptor antagonist SCH23390 ((5R)‐8‐chloro‐3‐methyl‐5‐phenyl‐1,2,4,5‐tetrahydro‐3‐benzazepin‐7‐ol) was established and validated, using its 8‐bromo analogue SKF83566 as an internal standard. This quantification method proved to be suitable for the characterization of SCH23390 binding to human D1 and D5 receptors. Following the concept of MS Binding Assays, saturation experiments for D1 and D5 receptors were performed, as well as competition experiments for D1 receptors. The results obtained are in good agreement with results from radioligand binding assays and therefore indicate that the established MS Binding Assays addressing D1 and D5 receptors are well‐suited substitutes for radioligand binding assays, the technique that has so far dominated affinity determinations toward these targets. 相似文献
146.
147.
Andrea Harrer Peter Wipfler Georg Pilz Katrin Oppermann Elisabeth Haschke-Becher Shahrzad Afazel J?rg Kraus Eugen Trinka Johann Sellner 《International journal of molecular sciences》2015,16(9):21832-21845
Fingolimod, an oral sphingosine 1-phosphate (S1P) receptor modulator, is approved for the treatment of relapsing forms of multiple sclerosis (MS). The interference with S1P signaling leads to retention particularly of chemokine receptor-7 (CCR7) expressing T cells in lymph nodes. The immunological basis of varicella zoster virus (VZV) infections during fingolimod treatment is unclear. Here, we studied the dynamics of systemic and intrathecal immune responses associated with symptomatic VZV reactivation including cessation of fingolimod and initiation of antiviral therapy. Key features in peripheral blood were an about two-fold increase of VZV-specific IgG at diagnosis of VZV reactivation as compared to the previous months, a relative enrichment of effector CD4+ T cells (36% versus mean 12% in controls), and an accelerated reconstitution of absolute lymphocytes counts including a normalized CD4+/CD8+ ratio and reappearance of CCR7+ T cells. In cerebrospinal fluid (CSF) the lymphocytic pleocytosis and CD4+/CD8+ ratios at diagnosis of reactivation and after nine days of fingolimod discontinuation remained unchanged. During this time CCR7+ T cells were not observed in CSF. Further research into fingolimod-associated VZV reactivation and immune reconstitution is mandatory to prevent morbidity and mortality associated with this potentially life-threatening condition. 相似文献
148.
Karsten König Peter Andersen Tuan Le Hans Georg Breunig 《Microscopy research and technique》2015,78(12):1154-1158
Multiphoton laser scanning microscopy commonly relies on bulky and expensive femtosecond lasers. We integrated a novel minimal‐footprint Ti:sapphire oscillator, pumped by a frequency‐doubled distributed Bragg reflector tapered diode laser, into a clinical multiphoton tomograph and evaluated its imaging capability using different biological samples, i.e. cell monolayers, corneal tissue, and human skin. With the novel laser, the realization of very compact Ti:sapphire‐based systems for high‐quality multiphoton imaging at a significantly size and weight compared to current systems will become possible. Microsc. Res. Tech. 78:1154–1158, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
149.
150.
Differential Effects of Indole and Aliphatic Glucosinolates on Lepidopteran Herbivores 总被引:1,自引:0,他引:1
René Müller Martin de Vos Joel Y. Sun Ida E. Sønderby Barbara A. Halkier Ute Wittstock Georg Jander 《Journal of chemical ecology》2010,36(8):905-913
Glucosinolates are a diverse group of defensive secondary metabolites that is characteristic of the Brassicales. Arabidopsis thaliana (L.) Heynh. (Brassicaceae) lines with mutations that greatly reduce abundance of indole glucosinolates (cyp79B2 cyp79B3), aliphatic glucosinolates (myb28 myb29), or both (cyp79B2 cyp79B3 myb28 myb29) make it possible to test the in vivo defensive function of these two major glucosinolate classes. In experiments with Lepidoptera that are not crucifer-feeding specialists, aliphatic and indole glucosinolates had an additive effect on Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) larval growth, whereas Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) and Manduca sexta (L.) (Lepidoptera: Sphingidae) were affected only by the absence of aliphatic glucosinolates. In the case of two crucifer-feeding specialists, Pieris rapae (L.) (Lepidoptera: Pieridae) and Plutella xylostella (L.) (Lepidoptera: Plutellidae), there were no major changes in larval performance due to decreased aliphatic and/or indole glucosinolate content. Nevertheless, choice tests show that aliphatic and indole glucosinolates act in an additive manner to promote larval feeding of both species and P. rapae oviposition. Together, these results support the hypothesis that a diversity of glucosinolates is required to limit the growth of multiple insect herbivores. 相似文献