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Ohne Zusammenfassung 相似文献
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Scattering of diffuse photon density waves by spherical inhomogeneities within turbid media: analytic solution and applications. 总被引:2,自引:0,他引:2
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D A Boas M A O''Leary B Chance A G Yodh 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(11):4887-4891
We present an analytic solution for the scattering of diffuse photon density waves by spherical inhomogeneities within turbid media. The analytic result is compared to experimental measurements. Close agreement between theory and experiment permits the use of the theory to determine the properties of unknown sphere-like objects embedded in turbid media. The analytic solution is extended to encompass several problems of practical interest in imaging, including the influence of multiple sources, multiple objects, and boundaries on the characterization of spherical inhomogeneities. We also extend the solution to encompass time-domain measurements. 相似文献
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P. H. Mogensen L. Jórgensen J. Boas M. Dam A. Vesterager G. Flesch P. K. Jensen 《Acta neurologica Scandinavica》1992,85(1):14-17
The effects of dextropropoxyphene on the steady-state kinetics of oxcarbazepine and its metabolites were investigated in eight patients with epilepsy or trigeminal neuralgia. One patient dropped out of the study, presumably due to side-effects of dextropropoxyphene. Dextropropoxyphene did not affect the plasma levels of the principal active metabolite, 10,11-dihydro-10-hydroxy-carbamazepine. Since dextropropoxyphene is known to increase the plasma levels of carbamazepine, leading to toxicity, the findings of this study suggest that oxcarbazepine is a useful alternative to carbamazepine when concomitant dextropropoxyphene therapy is required. 相似文献
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Dr. phil. F. Boas 《Pflügers Archiv : European journal of physiology》1882,28(1):562-566
Ohne Zusammenfassung 相似文献
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Acute effects of lamotrigine (BW430C) in persons with epilepsy 总被引:26,自引:19,他引:7
C D Binnie W van Emde Boas D G Kasteleijn-Nolste-Trenite R A de Korte J W Meijer H Meinardi A A Miller J Overweg A W Peck A van Wieringen 《Epilepsia》1986,27(3):248-254
Sixteen epileptic patients took single doses of lamotrigine, 120 mg or 240 mg. Six photosensitive patients showed reduction (with abolition in two) in photosensitivity after lamotrigine administration. Five subjects with frequent interictal spikes showed reduction in spike frequency over 24 h after lamotrigine administration. The half-life (t1/2) of lamotrigine in subjects taking sodium valproate was prolonged, whereas the t1/2 in subjects taking carbamazepine and/or phenytoin was reduced. The area under the curve of co-medication plasma levels was not affected by a single dose of lamotrigine. Five patients reported mild and generally transitory side effects; some of which represented exacerbation of preexisting complaints. 相似文献
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Adojaan M Kivisild T Männik A Krispin T Ustina V Zilmer K Liebert E Jaroslavtsev N Priimägi L Tefanova V Schmidt J Krohn K Villems R Salminen M Ustav M 《Journal of acquired immune deficiency syndromes (1999)》2005,39(5):598-605
An earlier study has indicated that a complex recombinant HIV-1 strain dominates the epidemic in Estonia. The objective of this study was to further investigate the molecular epidemiology and genetic structure of HIV-1 in Estonia. Most of the investigated individuals became infected after August 2000 when HIV-1 started to spread rapidly among Estonian intravenous drug users (IDUs). Two viral DNA regions, gag/pol and gp41, were sequenced and subtyped from peripheral blood mononuclear cells or plasma from 141 individuals. Phylogenetic analysis in the gp41 region revealed that the most frequent type of the virus among IDUs was a circulating recombinant form, CRF06_cpx, whereas a few samples showed highest sequence similarity to a subtype A strain circulating in Ukraine and Russia. Likewise, in the gag/pol region, most of the samples were classified as CRF06_cpx, with a few classified as subtype A. In this region, however, 16% of the sequences turned out to be mosaic unique recombinant forms consisting of CRF06_cpx and subtype A. At least 9 mosaic forms were identified, each with distinct patterns of multiple crossover. To characterize Estonian CRF06_cpx as well as recombinant isolates in more detail, 4 near-full-length HIV-1 genomes were sequenced. 相似文献
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Vilse, a conserved Rac/Cdc42 GAP mediating Robo repulsion in tracheal cells and axons 总被引:3,自引:0,他引:3
Lundström A Gallio M Englund C Steneberg P Hemphälä J Aspenström P Keleman K Falileeva L Dickson BJ Samakovlis C 《Genes & development》2004,18(17):2161-2171
Slit proteins steer the migration of many cell types through their binding to Robo receptors, but how Robo controls cell motility is not clear. We describe the functional analysis of vilse, a Drosophila gene required for Robo repulsion in epithelial cells and axons. Vilse defines a conserved family of RhoGAPs (Rho GTPase-activating proteins), with representatives in flies and vertebrates. The phenotypes of vilse mutants resemble the tracheal and axonal phenotypes of Slit and Robo mutants at the CNS midline. Dosage-sensitive genetic interactions between vilse, slit, and robo mutants suggest that vilse is a component of robo signaling. Moreover, overexpression of Vilse in the trachea of robo mutants ameliorates the phenotypes of robo, indicating that Vilse acts downstream of Robo to mediate midline repulsion. Vilse and its human homolog bind directly to the intracellular domains of the corresponding Robo receptors and promote the hydrolysis of RacGTP and, less efficiently, of Cdc42GTP. These results together with genetic interaction experiments with robo, vilse, and rac mutants suggest a mechanism whereby Robo repulsion is mediated by the localized inactivation of Rac through Vilse. 相似文献
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Cell culture-based transdominant genetic techniques provide new methods for discovering peptide/RNA modulators of cellular pathways. We applied this technology to isolate a peptide inhibitor of human rhinovirus. A green fluorescent protein (GFP)-scaffolded library of cDNA fragments was expressed in HeLa cells from a retroviral vector and screened for inhibitors of rhinovirus-mediated cell killing. A DNA clone, I421, increased cell survival in an HRV14 challenge assay from less than 0.5% to greater than 60%. It encodes a 53-amino-acid C-terminal extension of the GFP scaffold. Particular subclones of Hela cells expressing I421 (exemplified by I421dp3) show a delay in virus production and a 50-fold decrease in viral RNA levels at 6-8 h postinfection. HRV2, HRV14, and HRV16 show a dramatic decrease in plaque-forming ability on I421dp3 while Coxsackievirus B3 showed a small reduction. Levels of ICAM-1, the receptor for the main rhinovirus serotype, are not altered in I421dp3. 相似文献