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排序方式: 共有158条查询结果,搜索用时 78 毫秒
61.
Tobias Frank Johannes CM Schlachetzki Bettina G?ricke Katrin Meuer Gundula Rohde Gunnar PH Dietz Mathias B?hr Armin Schneider Jochen H Weishaupt 《BMC neuroscience》2009,10(1):49-10
Background
The hematopoietic Granulocyte-Colony Stimulating Factor (G-CSF) plays a crucial role in controlling the number of neutrophil progenitor cells. Its function is mediated via the G-CSF receptor, which was recently found to be expressed also in the central nervous system. In addition, G-CSF provided neuroprotection in models of neuronal cell death. Here we used the retinal ganglion cell (RGC) axotomy model to compare effects of local and systemic application of neuroprotective molecules. 相似文献62.
We present experimental results describing the influence of optical bias on the transient characteristics of gratings formed in photorefractive BSO. A transient peak is evident, and the properties of this peak can be controlled by suitable adjustment of the relative intensities of the optical beams involved. 相似文献
63.
64.
65.
S. Trajmar J. M. Ratliff G. Csanak D. C. Cartwright 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1992,22(2):457-462
Differential and integral cross section data for electron-impact excitation of the 21 P level in He have been critically reviewed. Experimental and theoretical results have been compared and a set of differential cross sections at 20° scattering angle in the 25 to 500 eV impact energy range has been deduced based on all available information. It is proposed that this set of data represents the most accurate inelastic differential cross sections available at the present time and could be used as a secondary standard for normalization of cross sections. 相似文献
66.
The 2,2',4,4',6,6'hexanitrostilbene, HNS, nucleant, used in the crystallisation of 2,4,6,trinitrotoluene, TNT, was precipitated from molten TNT and examined by differential scanning calorimetry, DSC, at several stages during purification by vacuum sublimation. During purification a broad endotherm, associated with nucleant decomposition, which could be resolved into two endotherms, depending on the sublimation temperature, was observed. Pure nucleant prepared at 70C showed a similar behaviour during thermal annealing for extended periods of time at >85C. Thus TNT, retained in the recrystallised HNS nucleant, may be migrating during the purification process or may occupy a range of lattice sites, which exhibit different activation energies for migration to the surface of the solid during thermal decomposition of the nucleant. Loss of TNT from the nucleant, during purification, could produce some free HNS. The activation energy for nucleant decomposition, which may be a two-stage processes with the initial mobility of the TNT being the limiting reaction, was estimated to be 210 kJ mol–. The lattice sites available for the TNT in the host HNS nucleant require elucidation and are the subject of further studies to be published at a later date. 相似文献
67.
Brian J. Brisdon Michael Cartwright Annabelle G. Hodson 《Journal of organometallic chemistry》1984,277(1):85-90
Dissolution of [MoCl(CO)2(η3-C3H4R)(NCMe)2] (R = H or Me) in methanol yields yellow conducting solutions containing the [Mo(CO)2(η3-C3H4R)(HOMe)3]+ cations. The same species are formed on dissolution of [Mo(CO)2(η3-C3H4R)(NCMe)3]BF4 in methanol, and one of the cations (R = Me) has been isolated as its tetrafluoroborate salt. There is strong spectroscopic evidence that hydrated allyldicarbonylmolybdenum(II) cations [Mo(CO)2(η3-C3H4R)(H2O)x]+ are present on dissolution of [MoCl(CO)2(η3-C3H4R)(NCMe)2] in deoxygenated water, and treatment of these solutions with bi- and tridentate ligands yields neutral complexes [MoCl(CO)2(η3-C3H4R)L2] (R = H or Me; L2 = 2,2′-bipyridine (bipy) or 2,2′-bipyridylamine (bpa)), and cationic species [Mo(CO)2(η3-C3H4R)L3]+ (R = H or Me; L3 = diethylenetriamine (dien) or bis(2-pyridylmethyl)amine (bpma)) respectively. The latter were isolated as their hexafluorophosphate salts. Addition of Ph4AsCl to basic methanolic solutions of [MoCl(CO)2(η3-C3H4R)(NCMe)2] causes the precipitation of the anionic molybdenum derivatives Ph4As[Mo2(CO)4(η3-C3H4R)2(μ-OMe)3] (R = H or Me). 相似文献
68.
G. Csanak D. C. Cartwright S. Trajmar 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,25(4):327-336
Experimental data for the average transferred angular momentum, 〈⊥〉, have been combined with experimental differential cross section [DCS] data for electron impact excitation of the 21 P and 31 P levels of helium to obtain the individual magnetic-sublevel differential cross-sections, [DCS M n ], in the natural (and atomic) coordinate system. First-order many-body theory (FOMBT) has been used to obtain corresponding theoretical predictions for DCS M n which are compared to these results. This comparison shows that FOMBT generally predictsM=+1 sublevel excitation DCS better than that forM=?1. 相似文献
69.
Tao Z Tehan EC Bukowski RM Tang Y Shughart EL Holthoff WG Cartwright AN Titus AH Bright FV 《Analytica chimica acta》2006,562(1):59-65
We designed and synthesized new armed 12-oxacrown-3s bearing oxygen donor arms and forming encapsulated complexes with metal ions. The ISEs based on the single armed 12-oxacrown-3s exhibited Na+ ion selectivity, while the ISE based on the double armed 12-oxacrown-3 exhibited Li+ ion selectivity. The conformational analysis was performed on the free armed 12-oxaciown-3s and the non-encapsulated and the encapsulated armed 12-oxacrown-3 complexes using a semi-empirical method. The conformational analysis indicated that all armed 12-oxacrown-3s structurally prefer the Na+ ion rather than the Li+ ion. Further, it became apparent that the single armed 12-oxacrown-3s without a guest cation have the C3v 12-oxaciown-3 ring and the double armed 12-oxacrown-3 without a guest cation has the bent 12-oxacrown-3 ring. The oxygens except carbonyl oxygens were directed toward the cation center in the structures of the complexes. It was clear that the ether and ester oxygens participate in the sidearm coordination. 相似文献
70.
Marijke WA de Backer Carlos P Fitzsimons Maike AD Brans Mieneke CM Luijendijk Keith M Garner Erno Vreugdenhil Roger AH Adan 《BMC neuroscience》2010,11(1):81