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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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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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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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Two dosages of Smokeless Tobacco (ST) extract were given to gravid Sprague-Dawley rats by oral gavage on gestational days (GD) 6-20. The low dosage contained ST extract equivalent to 1.33 mg/kg nicotine (STD-1), and the high dosage contained ST extract equivalent to 4.0 mg/kg nicotine (STD-2). Dams were dosed three times daily at 8 a.m., 11 a.m., and 2 p.m., thus providing total daily nicotine equivalent dosages of 4 mg/kg/day and 12 mg/kg/day. Controls received equivalent amounts of distilled water by gavage. Dams were allowed to deliver and all experimental pups were fostered to control mothers. On postnatal day 1 (PND 1) litters were culled to 4 +/- 1 females and 4 +/- 1 males. Weights, physical landmark development, and behavioral performance of pups were monitored during pre- and post-weaning periods. Behavioral tests included: surface righting, negative geotaxis, swimming development, open-field activity, active avoidance in shuttle box, and Cincinnati swimming maze. Our results show that the STD-2 dose resulted in reduced maternal weight gain. Offspring weights were reduced in a dose-related manner, with the most consistent weight deficits seen in the STD-2 group until PND29. Consistent STD-1 weight deficits were seen up to PND 8. The incidence of deaths was increased in the STD-2 dosage group. No significant treatment-related differences were observed in development of physical landmarks. Male STD-2 pups righted faster than controls, and significant differences were noted in swimming development with the STD-1 group of pups performing less effectively than controls. Activity levels, assessed during both pre- and post-weaning periods were not affected. No treatment-related differences were seen in the active avoidance shuttle box or Cincinnati swimming maze tests, which assessed learning. Female brain weights were reduced in the STD-1 treatment group.  相似文献   
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PURPOSE: This retrospective review of femorodistal vein grafts was analyzed to determine the usefulness of various graft surveillance criteria. METHOD: The surveillance schedule involved evaluations at 1 month, every 3 months the first year, and then every 6 months. Salvage intervention or graft occlusion occurring within the next follow-up interval defined surveillance end points. One hundred two grafts (329 surveillance visits) had an ankle/brachial index (ABI). A duplex scanning-determined midgraft peak systolic flow velocity (PSFV) was available for 81 grafts (262 visits). Forty-eight grafts (137 visits) had both a PSFV and entire graft duplex scanning (EGDS) to determine stenosis greater than 50%, whereas 40 grafts (91 visits) had simultaneous ABI and EGDS. RESULTS: When a greater than 15% decrease in ABI denoted an abnormal surveillance study result, a positive predictive value (PPV) of 24.3% and negative predictive value of 94.5% were noted. Similarly, a PSFV cutoff of less than 35 cm/sec demonstrated values of 26.3% and 94.2%, respectively. When an EGDS of greater than 50% stenosis or a PSFV of less than 35 cm/sec were the cutoff criteria, the PPV was 36.7% and negative predictive value 99.1%, whereas characterizing abnormal results further with ABI (> 15% decreases) increased the PPV to 83.3%. CONCLUSION: The combination of an EGDS, midgraft PSFV, and ABI provides optimal follow-up for our patients with a femorodistal vein graft.  相似文献   
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