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排序方式: 共有725条查询结果,搜索用时 453 毫秒
1.
Dr. Raysa Khan Tareque Dr. Storm Hassell-Hart Dr. Tobias Krojer Dr. Anthony Bradley Dr. Srikannathasan Velupillai Dr. Romain Talon Dr. Michael Fairhead Dr. Iain J. Day Kamlesh Bala Dr. Robert Felix Dr. Paul D. Kemmitt Prof. Paul Brennan Prof. Frank von Delft Dr. Laura Díaz Sáez Prof. Kilian Huber Prof. John Spencer 《ChemMedChem》2020,15(24):2513-2520
Combined photochemical arylation, “nuisance effect” (SNAr) reaction sequences have been employed in the design of small arrays for immediate deployment in medium-throughput X-ray protein–ligand structure determination. Reactions were deliberately allowed to run “out of control” in terms of selectivity; for example the ortho-arylation of 2-phenylpyridine gave five products resulting from mono- and bisarylations combined with SNAr processes. As a result, a number of crystallographic hits against NUDT7, a key peroxisomal CoA ester hydrolase, have been identified. 相似文献
2.
R Faccio M Grano S Colucci AZ Zallone V Quaranta AJ Pelletier 《Canadian Metallurgical Quarterly》1998,249(2):522-525
Integrins mediate cell adhesion and can induce different cellular responses, including changes in intracellular pH, changes and oscillation in intracellular free calcium, and protein phosphorylation on tyrosine. During bone resorption, the integrin alphav beta3 regulates adhesion of osteoclasts to bone extracellular matrix proteins, such us osteopontin (Opn). Adhesion via alphav beta3 is followed by osteoclast polarization onto the bone surface and by the onset of bone resorption. To characterize these events at the molecular level, we investigated the state of activation of alphav beta3 on the human osteoclast-like cell line GCT23 using the monoclonal antibody AP5 which binds to and can induce, under low calcium conditions, activated alphav beta3. By flow cytometry, approximately 50% of alphav beta3 on the surface of the osteoclast-like cell line GCT23 was reactive with AP5 and was therefore in the activated state. Incubation with AP5 in the presence of low calcium concentrations increased activated alphav beta3 to 90-100%. Activation of alphav beta3 increased the efficiency of GCT23 adhesion to Opn by 2-fold. Furthermore, haptotactic migration on Opn was also enhanced about 40% compared to control. We propose that changes in the activation state of alphav beta3 may be a regulation point for osteoclasts during bone resorption. 相似文献
3.
B. Van de Moortéle 《材料科学技术学报》2003,19(6)
The homogeneous plastic flow of fully amorphous and partially crystallized Zr(41.2)Ti(13.8)Cu(12.5)Ni(10)Be(22.5) bulk metallic glass (Vitl) has been investigated by compression tests at high temperatures in supercooled liquid region. Experimental results show that at sufficiently low strain rates, the supercooled liquid of the fully amorphous alloy reveals Newtonian flow with a linear relationship between the flow stress and strain rate. As the strain rate is increased, a transition from linear Newtonian to nonlinear flow is detected, which can be explained by the transition state theory. Over the entire strain rate interval investigated, however, only nonlinear flow is present in the partially crystallized alloy, and the flow stress for each strain rate is much higher. It is found that the strain rate-stress relationship for the partially crystaltized alloy at the given temperature of 646 K also obeys the sinh law derived from the transition state theory, similar to that of the initial homogeneous amo 相似文献
4.
5.
M Carrier TK Leung BC Solymoss R Cartier Y Leclerc LC Pelletier 《Canadian Metallurgical Quarterly》1996,61(5):1310-4; discussion 1314-5
BACKGROUND: A prospective, randomized clinical study involving 34 patients undergoing heart transplantation compared myocardial preservation of donor hearts maintained with continuous reperfusion with retrograde warm blood cardioplegia during surgical implantation versus the standard cold topical irrigation. METHODS: Hearts in both groups were arrested with a standard crystalloid solution and maintained in a cold saline solution during transportation. In the retrograde group, cardioplegia was administered through a catheter in the coronary sinus during surgical implantation. An average of 471 +/- 30 mL of hyperkalemic crystalloid solution diluted 1:4 in warm blood from the oxygenator was infused. In the standard group, the heart was kept cold by topical irrigation of cold saline solution and was reperfused only when the ascending aorta was unclamped. RESULTS: Preoperative characteristics of donors and recipients were similar in the two cohorts. Ischemic time average 139 +/- 12 minutes in the retrograde group compared with 130 +/- 11 minutes in the standard group (p = 0.57). Cardiopulmonary bypass time averaged 89 +/- 4 minutes in the retrograde group and 110 +/- 12 minutes in the standard group (p = 0.12). Defibrillation at reperfusion was performed in 4 patients (4/17, 24%) in the retrograde group and 12 patients (12/18, 67%) in the standard group (p = 0.01). There were no deaths in the retrograde group (0/17), whereas in the standard group, 3 patients (3/17) died of early graft failure (p = 0.11). Four early graft failures occurred in the standard group (p = 0.06). Two patients (2/17, 12%) were weaned from bypass with ventricular assist devices in the standard group. The number of subendocardial necrotic cells in the first two weekly endomyocardial biopsy specimens averaged 2.7 +/- 0.8 cells/mm2 in the retrograde group and 5.9 +/- 2.4 cells/mm2 in the standard group (p = 0.12). CONCLUSIONS: Retrograde warm blood reperfusion appears to improve the initial recovery of transplanted hearts. The technique is easy to use and may be a useful approach to graft protection during surgical implantation. 相似文献
6.
We measure the refractive index of thin films of TiO2 and SiO2 for given deposition parameters. Two complementary methods are used. The first is a postdeposition technique which uses the measurements of reflectance and transmittance in air. The second, in contrast, makes use of in situ measurements (under vacuum and during the actual deposition of the layer). The differences between the values deduced from the two methods can be explained by the amount of atmospheric moisture adsorbed by films. One tries to minimize these shifts for the two materials by choosing deposition parameters. The difficulties come from the absorption losses which must be as small as possible. We use the measured refractive indices of individual layers to give good numerical prediction of the wavelength shift (observed during the admittance of air after deposition in the vacuum chamber) of the transmittance peak of multidielectric Fabry-Perot filters. 相似文献
7.
Ole Becker Peter Sopade Romain Bourdonnay Peter J. Halley George P. Simon 《Polymer Engineering and Science》2003,43(10):1683-1690
The effect of an organically surface modified layered silicate on the viscosity of various epoxy resins of different structures and different functionalities was investigated. Steady and dynamic shear viscosities of the epoxy resins containing 0–10 Wt% of the organoclay were determined using parallel plate rheology. Viscosity results were compared with those achieved through addition of a commonly used micronsized CaCO3 filler. It was found that changes in viscosities due to the different fillers were of the same order, since the layered silicate was only dispersed on a micron‐sized scale in the monomer (prior to reaction), as indicated by X‐ray diffraction measurements. Flow activation energies at a low frequency were determined and did not show any significant changes due to the addition of organoclay or CaCO3. Comparison between dynamic and steady shear experiments showed good agreement for low layered silicate concentrations below 7.5 wt%, i.e. the Cox‐Merz rule can be applied. Deviations from the Cox‐Merz rule appeared at and above 10 wt%, although such deviations were only slightly above experimental error. Most resin organoclay blends were well predicted by the Power Law model, only concentrations of 10 wt% and above requiring the Herschel‐Buckley (yield stress) model to achieve better fits. Wide‐angle X‐ray measurements have shown that the epoxy resin swells the layered silicate with an increase in the interlayer distance of approximately 15 Å, and that the rheology behavior is due to the lateral, micron‐size of these swollen tactoids. 相似文献
8.
This paper presents GPELab (Gross–Pitaevskii Equation Laboratory), an advanced easy-to-use and flexible Matlab toolbox for numerically simulating many complex physics situations related to Bose–Einstein condensation. The model equation that GPELab solves is the Gross–Pitaevskii equation. The aim of this first part is to present the physical problems and the robust and accurate numerical schemes that are implemented for computing stationary solutions, to show a few computational examples and to explain how the basic GPELab functions work. Problems that can be solved include: 1d, 2d and 3d situations, general potentials, large classes of local and nonlocal nonlinearities, multi-components problems, and fast rotating gases. The toolbox is developed in such a way that other physics applications that require the numerical solution of general Schrödinger-type equations can be considered. 相似文献
9.
Boris Raymond Gaël Guennebaud Pascal Barla Romain Pacanowski Xavier Granier 《Computer Graphics Forum》2014,33(2):313-321
This paper introduces a system for the direct editing of highlights produced by anisotropic BRDFs, which we call anisotropic highlights. We first provide a comprehensive analysis of the link between the direction of anisotropy and the shape of highlight curves for arbitrary object surfaces. The gained insights provide the required ingredients to infer BRDF orientations from a prescribed highlight tangent field. This amounts to a non‐linear optimization problem, which is solved at interactive framerates during manipulation. Taking inspiration from sculpting software, we provide tools that give the impression of manipulating highlight curves while actually modifying their tangents. Our solver produces desired highlight shapes for a host of lighting environments and anisotropic BRDFs. 相似文献
10.
Romain Fillières Bouchra Benjelloun-Mlayah Michel Delmas 《Journal of the American Oil Chemists' Society》1995,72(4):427-432
High-performance size-exclusion chromatography (HPSEC) was used to evaluate the influence of different variables affecting
the transesterification of rapeseed oil (RSO) with anhydrous ethanol and sodium ethoxide as catalyst. The effect of temperature,
ethanol/RSO molar ratio, catalyst concentration, and time can be interpreted by observing the variations of the reaction medium
composition. HPSEC has made the quantitation of ethyl esters, mono-, di-, and triglycerides and glycerol possible. The best
results for laboratory-scale reactions were obtained at 80°C with a 6:1 molar ratio of EtOH/RSO and 1% of NaOEt by weight
of RSO. 相似文献