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The iron status of 22 children and adolescents with Crohn's disease (mean age: 13 years) was evaluated. Eleven patients were suffering from active disease with inflammation, identified by at least one abnormal value for serum orosomucoid, C-reactive protein or sedimentation rate (group I). Eleven patients were in clinical remission and showed no biological evidence of inflammation (group II). Hemoglobin and red cell indices, erythrocyte protoporphyrin, serum iron, transferrin, serum ferritin and basic red cell ferritin were determined in all patients. The usual indicators of iron status, particularly serum ferritin, were affected by the inflammatory processes, but basic red cell ferritin appeared to be independent of inflammation. Basic red cell ferritin can therefore be considered to be a reliable indicator of iron status in children and adolescents with Crohn's disease. 相似文献
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DF Muir 《Canadian Metallurgical Quarterly》1997,4(4):292-303
Tumor development and progression in the nervous system are poorly understood. Consequently, even though there seems to be little possibility of major advances in existing clinical modalities used to treat malignant brain tumors, no targeted molecular therapies have risen to take their place. The variability and plasticity of brain neoplasms make them an illusive target for study and therapeutic intervention. Further complicated by infiltration of vital nervous tissue, clinical studies have serious practical limitations and the ability to assess tumor progression in vivo is still a developing technology. Evaluation of potential new therapies for brain tumors is heavily dependent on the development of more informative and cognate experimental models. To develop and validate new models, it is particularly important to integrate clinical, pathological, and cell biological characterizations of malignant brain tumors. This discussion provides an overview of developments in tumor cell culture and the impact of animal models on brain tumor research. Studies of malignant glial neoplasms associated with a dismal prognosis in patients receive particular attention. 相似文献
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L Bini B Magi B Marzocchi F Arcuri S Tripodi M Cintorino JC Sanchez S Frutiger G Hughes V Pallini DF Hochstrasser P Tosi 《Canadian Metallurgical Quarterly》1997,18(15):2832-2841
Reference two-dimensional (2-D) gels are presented for human breast ductal carcinoma and histologically normal tissue. Whole biopsy fragments were analyzed, including epithelial and nonepithelial components. Thirty-five spots have been assigned by gel matching to the human liver SWISS-2DPAGE reference map and/or to the human primary keratinocyte IPG map from the Danish Center for Human Genome. N-terminal microsequencing was applied to confirm randomly chosen matching assignments and to identify six new spots. Protein expression profiles in ductal carcinoma and in normal breast tissue appeared to be similar, except for a pattern consisting of 32 spots, which were highly expressed in all carcinoma specimens, and less intense and occasionally undetectable in normal tissue. This difference was statistically significant. Assignment has been obtained for several spots, namely GRP94, GRP78, GRP75, mitochondrial HSP60, calreticulin, protein disulfide isomerase, peptidyl-prolyl cis-trans isomerase, collagen-binding protein 2, fructose bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, thioredoxin, cytochrome c oxidase VA subunit, tubulin beta isoform and macrophage migration inhibitory factor (MIF). The cancer- and tissue-specificity of the described pattern was assessed by matching to the Swiss-2DPAGE human liver, hepatoma, lymphoma, erythroleukemia reference maps. The pattern of 32 spots was found to be indicative of epithelial neoplasia. 相似文献
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1. The construction of three-dimensional models of CYP2B isozymes from rat (CYP2B1), rabbit (CYP2B4) and man (CYP2B6), based on a multiple sequence alignment with CYP102, a unique eukaryotic-like bacterial P450 (in terms of possessing an NADPH-dependent FAD- and FMN-containing oxidoreductase redox partner) of known crystal structure, is reported. 2. The enzyme models described are shown to be consistent with experimental evidence from site-directed mutagenesis studies, antibody recognition sites and amino acid residues identified as being associated with redox partner interactions, together with the location of a key serine residue (Ser-128) likely to be involved in protein kinaseA-mediated phosphorylation. 3. A substantial number of known substrates and inhibitors of CYP2B isozymes are shown to fit the putative active sites of the enzyme models in agreement with their reported position of metabolism or mode of inhibition respectively. In particular, there is complementarity between the characteristic non-planar geometries of CYP2B substrates and key groups in the enzymes' active sites. 4. Molecular modelling of CYP2B isozymes appears to rationalize a number of the reported findings from quantitative structure-activity relationship investigations on series of CYP2B substrates and inhibitors. 相似文献
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A. T. Adorno C. R. S. Beatrice A. V. Benedetti P. L. Cabot 《Journal of Materials Science》1993,28(2):411-414
Electrical resistivity measurements and scanning electron microscopy was used to study the dissolution of silver on Cu-Ag and Cu-Al-Ag alloys. The results seem to indicate that the dissolution temperature is affected by the addition of aluminium. 相似文献