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The spectrum of cranial MRI findings was evaluated in 113 patients with the acquired immunodeficiency syndrome, assessing lesion number, size, location, and configuration in association with the autopsy and/or biopsy results. Correlation of cranial MRI and CT was performed in 32 patients. MRI was shown to be superior in sensitivity of lesion detection demonstrating more lesions than CT in 14 studies (44%) and equivalent information in 18 studies (56%). In no case did CT demonstrate lesions not detected on MRI. We conclude that MRI should be the study of choice in evaluating AIDS-related encephalopathy. Multiple lesions that involve both deep gray matter and white matter suggest the possibility of CNS lymphoma. The "target" appearance on MRI is not helpful in distinguishing toxoplasmosis from lymphoma. 相似文献
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Govorukhina NI Keizer-Gunnink A van der Zee AG de Jong S de Bruijn HW Bischoff R 《Journal of chromatography. A》2003,1009(1-2):171-178
LC-MS is a powerful method for the sensitive detection of proteins and peptides in biological fluids. However, the presence of highly abundant proteins often masks those of lower abundance and thus generally prevents their detection and identification in proteomic studies. In human serum the most abundant proteins are albumin and gamma-globulins. We tested several approaches to specifically reduce the level of these proteins based on either specific antibodies, dye ligands (for albumin) and protein A or G (for gamma-globulins). The resulting, depleted serum was analyzed by sodium dodecylsulfate-polyacrylamide gel electrophoresis and LC-MS for the residual presence of these abundant proteins as well as for other serum proteins that should remain after depletion. To test the applicability of this method to real-life samples, depleted serum of a cervical cancer patient was analyzed for the presence of a specific tumor marker protein SCCA1 (squamous cell carcinoma antigen 1; P29508), which is present at ng/ml concentrations. The results demonstrate that SCCA1 can be detected by LC-MS in patient serum following depletion of albumin and gamma-globulins thus opening the possibility of screening patient sera for other, so far unknown, tumor markers. 相似文献
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Kishore Kumar Sankara Layne T. Watson 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1985,36(6):845-853
Summary This paper studies the flow of an incompressible, constant density micropolar fluid past a stretching sheet. The governing boundary layer equations of the flow are solved numerically using a globally convergent homotopy method in conjunction with a least change secant update quasi-Newton algorithm. The flow pattern depends on three non-dimensional parameters. Some interesting results are illustrated graphically and discussed.
This work performed at Sandia National Laboratories supported by the U. S. Department of Energy under contract number DE-AC04-76DP00789. 相似文献
Résumé Nous étudions l'écoulement d'un fluid micropolaire et incompressible, de densité constante, le long d'une surface qui l'étend. Les équations de la couche limite qui régissent l'écoulement sont résolues numériquement. On utilise un algorithme quasi-Newtonien de type least change secant update avec une méthode homotopique /`a convergence globale. Certains résultats intéressants sont discutés et illustrés graphiquement.
This work performed at Sandia National Laboratories supported by the U. S. Department of Energy under contract number DE-AC04-76DP00789. 相似文献
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Alexander Boichenko Natalia Govorukhina Ate G. J. van der Zee Rainer Bischoff 《Analytical and bioanalytical chemistry》2013,405(10):3195-3203
Macroporous reversed-phase (mRP) chromatography was successfully used to develop an accurate and precise method for total protein in serum. The limits of detection (0.83 μg, LOD) and quantification (2.51 μg, LOQ) for the mRP method are comparable with those of the widely used micro BCA protein assay. The mRP method can be used to determine the total protein concentration across a wide dynamic range by detecting chromatographic peaks at 215 nm and 280 nm. The method has the added advantage of desalting and denaturing proteins, leading to more complete digestion by trypsin and to better LC–MS–MS identification in shotgun proteomics experiments. Figure
Simultaneous Serum Desalting and Total Protein Determination with Macroporous Reversed-Phase Chromatography: calibration plots 相似文献
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Prof. Mengtao Sun Dr. Zhenglong Zhang Prof. Zee Hwan Kim Prof. Hairong Zheng Prof. Hongxing Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(44):14958-14962
Heterogeneous catalysts play an important role in surface catalytic reactions, but selective bond breaking and control of reaction products in catalytic processes remain significant challenges. High‐vacuum tip‐enhanced Raman spectroscopy (HV‐TERS) is one of the best candidates to realize surface catalytic reactions. Herein, HV‐TERS was employed in a new method to control dissociation by using hot electrons, generated from plasmon decay, as plasmonic scissors. In this method, the N?N bond in 4,4′‐dimercaptoazobenzene was selectively dissociated by plasmonic scissors, and the reaction products formed from the radical fragment (SC6H5N) were controlled by varying the pH value. Under acidic conditions, p‐aminothiophenol was produced from the radical fragment by attachment of hydrogen ions, whereas under alkaline conditions, 4‐nitrobenzenethiol was obtained by attachment of oxygen ions to the substrate. 相似文献
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