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11.
'Gliosarcomas' have long been considered to be mixed gliomas and sarcomas. The present study failed to define criteria which clearly delineate 'gliosarcomas' from glioblastoma multiforme and suggests that 'gliosarcomas' should be considered as spindle cell glioblastomas. A total of six cases originally diagnosed as 'gliosarcomas' were compared with four cases of glioblastoma multiforme. No clinical or prognostic features were defined which would clearly separate 'gliosarcomas' from glioblastoma multiforme. Macroscopically, biopsies from 'gliosarcomas' ranged from firm, apparently well-circumscribed tumours to poorly circumscribed lesions with a soft consistency resembling glioblastoma multiforme. Histology revealed a continuous spectrum in which 'gliosarcomas' with large reticulin-rich areas of spindle cells merged with typical glioblastomas containing only small islands of spindle cells and reticulin staining. Immunocytochemistry for glial fibrillary acidic protein (GFAP); S100 protein and alpha-smooth muscle actin (ASMA) showed that the majority of cells in reticulin-poor areas of 'gliosarcoma' and glioblastomas expressed S100 protein and GFAP; many expressed ASMA and some expressed both GFAP and ASMA. Spindle cells in reticulin-rich areas of 'gliosarcomas' and glioblastomas most frequently expressed ASMA but many cells also expressed S100 protein and GFAP; some cells expressed both GFAP and ASMA. The results of this study and a review of the literature suggests that there is a clinical, radiological and pathological continuum with glioblastoma and 'gliosarcoma' at different ends of the spectrum. It is suggested, therefore, that most, if not all, 'gliosarcomas' be redesignated as spindle cell glioblastomas and not be considered as a mixture of glioma and sarcoma. 相似文献
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George A. Fielding 《Journal of hepato-biliary-pancreatic sciences》2002,9(6):723-728
The modern surgeon's approach to choledocholithiasis depends his or her view of cholangiography. During the early 1990 there was a swing away from cholangiography, which had previously been common practice. This was because of perceptions of difficulty with the technique, the time it took, and perhaps an implied increase in costs because of the time factor. There was no evidence on which to base this decision. This led to a marked upswing in the use of endoscopic retrograde cholangiopancreatography (ERCP). There were a large number of ERCPs with normal results performed prior to laparoscopic cholecystectomy. This paper states the case for intraoperative cholangiography and common bile duct clearance at the time of cholecystectomy. It is hoped that this technique will be adopted so patients can undergo a single procedure to remove their gallstones and common bile duct stones if they exist and to decrease the incidence of normal preoperative ERCPs and the need for a second procedure postoperatively to clear stones if they are found. 相似文献
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The β‐adhesin part of the Porphyromonas gingivalis W50 (ATCC 53978) protease HRgpA was cloned in an eukaryotic expression vector and expressed in COS‐7 cells. The monoclonal antibody MAb (61BG1.3), specific for the hemagglutinating domain of β‐adhesin, recognized the expressed β‐adhesin in the transfected cells both by immunoblot and immunofluorescence. Sprague Dawley rats were immunized intramuscularly with β‐adhesin encoding expression plasmid and expression plasmid without β‐adhesin insert. Skeletal muscle tissue at the site of immunization in the β‐adhesin immunized animals was shown to express this protein. The immunization induced a β‐adhesin‐specific antibody response. Sera from the immunized animals were tested for hemagglutination inhibiting activity. Due to high natural inhibiting activity in all rat sera tested, no increased hemagglutination inhibition was detected in sera from the β‐adhesin immunized animals. 相似文献
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J.K. MOHANA RAO 《Chemical biology & drug design》1987,29(2):276-281
Based on residue characteristic physical parameters, a new scoring matrix, called EMPAR, for amino acid exchanges in proteins was obtained. When comparing protein sequences for detecting homologies, the use of this matrix in place of the Dayhoff log-odds matrix yields results that reflect the topological similarities in the proteins. The use of EMPAR is equivalent to the parametric correlation coefficient approach of Ooi and his colleagues. This matrix correlates at 0.63 with the Dayhoff matrix. 相似文献
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HPLC analysis of the embryo-toxic fraction of human uterinefluid, collected between the 22nd and 25th days of the menstrualcycle, revealed the presence of cholic acid at high concentrations.It is suggested that cholic acid could be responsible for theembryo-toxicity of the uterine environment, which follows thereceptive period for implantation. 相似文献
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