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21.
P Katrak G Bowring P Conroy M Chilvers R Poulos D McNeil 《Canadian Metallurgical Quarterly》1998,79(7):758-761
We describe a rare case of pleomorphic type of malignant fibrous histiocytoma (MFH) in the buttock that presented a systemic involvement. The case was of a 58-year-old woman presenting hepatic dysfunction and inflammatory reactions including fever, positive C-reactive protein (CRP), an elevated erythrocyte sedimentation rate, and high levels of platelets and ferritin. The fever of 3 months duration subsided on the first postoperative day. The MFH resection also brought rapid normalization in CRP, platelets, and leukocytes. The local and systemic productions of cytokines induced by this tumor were evaluated. In vivo and in vitro production of interleukin (IL)-6, IL-1beta, and tumor necrosis factor alpha by tumor cells were measured using enzyme-linked immunosorbent assay. Blood samples taken preoperatively, tumor tissues, and the primary culture medium showed extraordinarily high IL-6 levels. The plasma IL-6 level was normalized postoperatively. Immunohistochemistry showed the positivity of tumor cells for IL-6. The IL-6 produced by the tumor was concluded to have been responsible for the systemic illness. 相似文献
22.
The poly(C60-co-styrene)s prepared by radical copolymerizations of C60 and styrene in bulk were characterized by multiple-detector size-exclusion chromatographs consisting of a refractometer, a differential viscometer, and/or a right-angle laser-light scattering photometer. The multidetector systems enabled the determinations of reliable, absolute molecular weights of the copolymers. The plots of intrinsic viscosity vs. molecular weight and radius of gyration vs. molecular weight offered valuable information about the molecular architectures of the copolymers. The slopes of the plots reveal that the structure of the copolymer changes with its C60 content: the copolymer with a low C60 content of 0.58 wt% possesses a linear structure, whereas its conger with a high C60 content of 1.14 wt% possesses a branched structure. 相似文献
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In this paper the role of microstructure and residual stresses on fatigue crack initiation of gaseous carbonitrided steels is examined. Optimum for austenite content in the case is investigated for microstructures containing bainite and for those without bainite. Fractographic study suggests subsurface initiation sites for notched specimens when austenite content is high and initiation sites at the surface when austenite is low. 相似文献
24.
Yongqiang?Dong Jacky?W.?Y.?Lam Zhen?Li Anjun?Qin Hui?Tong Yuping?Dong Xinde?FengEmail author Ben?Zhong?Tang 《Journal of Inorganic and Organometallic Polymers and Materials》2005,15(2):287-291
The photoluminescence (PL) of the thin layer of hexaphenylsilole (HPS) on thin-layer chromatograph (TLC) or quartz plate is investigated. The PL of the HPS layer absorbed on the TLC plate can be turned “off” and “on” continuously and reversibly by solvent exposure and evaporation. On the other hand, the PL of the HPS film coated on the quartz plate becomes stronger with a blue-shift in its emission color after fumigation by solvent vapor. After solvent removal, the film does not return to its original blue-green emission. Analyses by SEM, TEM and XRD indicate that the transformation from amorphous to crystalline state is responsible for the vapor-induced stronger and bluer PL. 相似文献
25.
Basicity and oxidation of S82? and S32? polysulphide ions in dimethylacetamide (DMA), prepared by electrochemical reduction of sulphur, have been studied by voltammetry coupled with visible absorption spectrophotometry. The protonation os S3.? radical anion is not observed in DMA. The pKA value of HS8? stands between 7 and 9. pKA values of HS3? and HS4? are higher than 13. For each S82?, S42? and S32? ions, protonation and oxidation are simultaneously observed from the same acidity level. 相似文献
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Chong Chiu Pablo Moreno Neil Todreas Robert Bowring 《Nuclear Engineering and Design》1979,53(2):165-186
Assessment is made of the error in enthalpy predictions in PWR cores resulting from various assumptions in the size of homogenized calculation regions. A coefficient is developed from the differential conservation equations and numerically determined to minimize these errors. It was found that these errors are only of significance for regions comprising three to seven subchannels, region sizes which may be employed in coupled neutronic-thermal hydraulic calculations. A correlation for coefficient values for a range of PWR conditions is presented. 相似文献
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Leung KK Holden M Saeed N Brooks KJ Buckton JB Williams AA Campbell SP Changani K Reid DG Zhao Y Wilde M Rueckert D Hajnal JV Hill DL 《IEEE transactions on medical imaging》2006,25(12):1617-1626
Recent innovations in drug therapies have made it highly desirable to obtain sensitive biomarkers of disease progression that can be used to quantify the performance of candidate disease modifying drugs. In order to measure potential image-based biomarkers of disease progression in an experimental model of rheumatoid arthritis (RA), we present two different methods to automatically quantify changes in a bone in in-vivo serial magnetic resonance (MR) images from the model. Both methods are based on rigid and nonrigid image registration to perform the analysis. The first method uses segmentation propagation to delineate a bone from the serial MR images giving a global measure of temporal changes in bone volume. The second method uses rigid body registration to determine intensity change within a bone, and then maps these into a reference coordinate system using nonrigid registration. This gives a local measure of temporal changes in bone lesion volume. We detected significant temporal changes in local bone lesion volume in five out of eight identified candidate bone lesion regions, and significant difference in local bone lesion volume between male and female subjects in three out of eight candidate bone lesion regions. But the global bone volume was found to be fluctuating over time. Finally, we compare our findings with histology of the subjects and the manual segmentation of bone lesions. 相似文献