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991.
PA Knolle A Uhrig S Hegenbarth E L?ser E Schmitt G Gerken AW Lohse 《Canadian Metallurgical Quarterly》1998,114(3):427-433
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OBJECTIVE: To test the hypothesis of an association between neonatal intramuscular vitamin K and childhood leukaemia and other cancers. DESIGN: Population based case-control study with data abstracted from hospital records. SETTING: Scotland. SUBJECTS: Children aged 0-14 years resident in Scotland from 1991-4 and diagnosed with leukaemia (150), lymphomas (46), central nervous system tumours (79), a range of other solid tumours (142), and a subset of acute lymphoblastic leukaemia (129). Controls were 777 children matched for age and sex, providing 417 matched sets (360 triplets and 57 pairs) for analysis. MAIN OUTCOME MEASURE: Odds ratios for the risk of childhood leukaemia and cancer and intramuscular vitamin K versus a combined group of oral doses, none, and no record. Results are given for information recorded in medical notes and data supplemented by hospital policy. RESULTS: Odds ratios based on medical record abstractions showed no significant positive association for leukaemias (odds ratio 1.30; 95% confidence interval 0.83 to 2.03), acute lymphoblastic leukaemia (1.21; 0.74 to 1.97), lymphomas (1.06; 0.46 to 2.42), central nervous system tumours (0.74; 0.40 to 1.34), and other solid tumours (0.59; 0.37 to 0.96). There was no association with acute lymphoblastic leukaemia in children aged 1 to 6 years. Imputation of exposure from hospital policy gave similar results. Adjustment for deprivation and type of delivery moved risk estimates closer to unity for all major diagnostic groups. CONCLUSIONS: The observation of an increased risk of childhood leukaemia and cancer associated with intramuscular vitamin K is not confirmed by this independent population based study. 相似文献
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A 50-year-old man was admitted to our hospital for possible surgery. Echocardiogram showed severe calcification of the aortic valve, and cardiac catheter examination recorded a gradient greater than 150 mmHg across the valve. These results determined aortic valve replacement (AVR) to relieve the pressure-overloaded ventricle. Preoperative evaluations however, demonstrated anemia derived from hereditary spherocytosis (HS), an inherited hemolytic disorder. In order to avoid homologous blood transfusion, the following strategies were tried; 1) an iron supplement and an injection of recombinant human erythropoietin (rHuEPO); 2) pre- and perioperative autologous blood transfusion; and 3) an aggressive iron supplement just after the surgery. These raised the blood hemoglobin concentration to the criterion where autologous blood donation was started, and maintained the hemoglobin level stable, up to his discharge. In conclusion, bloodless cardiac surgery is possible for cases with anemia, and some strategies should be tried to raise and maintain the blood hemoglobin concentration well. 相似文献
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GJ Ding PA Fischer RC Boltz JA Schmidt JJ Colaianne A Gough RA Rubin DK Miller 《Canadian Metallurgical Quarterly》1998,273(44):28897-28905
A new quantitative cytometric technique, termed the ArrayScanTM, is described and used to measure NF-kappaB nuclear translocation induced by interleukin (IL)-1 and tumor necrosis factor-alpha (TNFalpha). The amount of p65 staining is measured in both the nuclei defined by Hoechst 33342 labeling and in the surrounding cytoplasmic area within a preselected number of cells/well in 96-well plates. Using this technique in synchronously activated human chondrocytes or HeLa cells, NF-kappaB was found to move to the nucleus with a half-time of 7-8 min for HeLa and 12-13 min for chondrocytes, a rate in each case about 4-5 min slower than that of Ikappa Balpha degradation. IL-1 receptor antagonist and anti-TypeI IL-1 receptor antiserum on the one hand and anti-TNFalpha and monoclonal anti-TNF receptor 1 antibodies on the other hand could be shown to respectively inhibit IL-1 and TNFalpha stimulation in both cell types. In contrast, a polyclonal anti-TNF receptor 1 antiserum exhibited both a 50% agonism and a 50% antagonism to a TNFalpha stimulation in a dose-dependent fashion, indicating that subtle functional responses to complex agonist and antagonist stimuli could be measured. The effects of different proteasome inhibitors to prevent Ikappa Balpha degradation and subsequent NF-kappaB translocation could also be discriminated; Leu-Leu-Leu aldehyde was only a partial inhibitor with an IC50 of 2 microM, while clastolactacystin beta-lactone was a complete inhibitor with an IC50 of 10 microM. The nonselective kinase inhibitor K252a completely inhibited both IL-1 and TNFalpha stimulation in both cell types with an IC50 of 0.4 microM. This concentration, determined after a 20-min stimulation, was shown to be comparable with that obtained for inhibition of IL-6 production induced by a 100-fold lower IL-1 and TNFalpha concentration measured after 17 h of stimulation. These results suggest that the ArrayScanTM technology provides a rapid, sensitive, quantitative technique for measuring early events in the signal transduction of NF-kappaB. 相似文献
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AL Vandenbogaerde A Kamuhabwa E Delaey BE Himpens WJ Merlevede PA de Witte 《Canadian Metallurgical Quarterly》1998,45(2-3):87-94
Pseudohypericin and hypericin, the major photosensitizing constituents of Hypericum perforatum, are believed to cause hypericism. Since hypericin has been proposed as a photosensitizer for photodynamic cancer therapy, the photocytotoxicity of its congener pseudohypericin has been investigated. The presence of foetal calf serum (FCS) or albumin extensively inhibits the photocytotoxic effect of pseudohypericin against A431 tumour cells, and is associated with a large decrease in cellular uptake of the compound. These results suggest that pseudohypericin, in contrast to hypericin, interacts strongly with constituents of FCS, lowering its interaction with cells. Since pseudohypericin is two to three times more abundant in Hypericum than hypericin and the bioavailabilities of pseudohypericin and hypericin after oral administration are similar, these results suggest that hypericin, and not pseudohypericin, is likely to be the constituent responsible for hypericism. Moreover, the dramatic decrease of photosensitizing activity of pseudohypericin in the presence of serum may restrict its applicability in clinical situations. 相似文献
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