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Epidermal growth factor receptor (EGFR) exon 18-21 mutations were shown to be highly predictive of response to gefitinib (Iressa) therapy in lung cancer. Studies on Western and Japanese lung cancers have indicated substantial differences in the EGFR mutation frequency between these populations. To investigate the prevalence of EGFR in another distinct ethnic group, EGFR alterations were studied in 47 consecutive non small cell lung cancers from Saudi Arabia by immunohistochemistry, fluorescence in situ hybridization, and DNA sequencing. Detectable EGFR expression was seen in 69.8% of 43 interpretable cancers. Epidermal growth factor receptor amplification, present in 15.3% of 39 analyzable cancers, was strongly associated with high levels of EGFR expression (P = .0047). Only 1 exon 18-21 mutation was seen among 34 lung cancers that could be successfully sequenced. It is concluded that EGFR exon 18-21 mutations are rare in Middle East patients with lung cancer and occur in a similar range as in Western patients. The remarkable high rate of EGFR gene amplifications could potentially facilitate studies on the predictive role of gene copy number changes for response to anti-EGFR therapies in Middle East patient sets.  相似文献   
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IntroductionThe aim of this study was to compare the fracture resistance of endodontically treated premolars after the application of three restorative materials (i.e., direct composite, indirect composite, and computer aided design/computer aided manufacturing CAD/CAM ceramic inlays) to restore a conservative occluso-mesial cavity preparation.Materials and methodssixty sound maxillary premolars were divided into four experimental groups; group A: the control group, where neither root canal treatment nor preparation were performed; group B: teeth were restored with a direct Filtek Z250 composite restorative material; group C: teeth were restored with an indirect inlay Filtek Z250 composite restorative material; group D: teeth were restored with IPS E.Max CAD/CAM monolithic ceramic inlays. Access cavities and root canal treatment procedures were conducted using standard techniques. Then, the cavities were restored with direct composite restorative materials following manufacturer’s instructions. Each group received mesial-occlusal cavities and restored according to the designated group.Teeth from all groups were exposed to a thermocycling regimen of 500 cycles in water baths at 5–55 °C. Then, each specimen was mounted on a special fixture on a computer controlled Instron Universal Testing Machine. An axial compressive load was applied to the palatal cusp up to failure at an angle of 45°. The force was applied at the rate of 2 mm/min until visible or audible evidence of fracture was observed. The force at fracture was measured in MPa, and the fracture mode was recorded as either favorable [restorable adhesive fracture above the cemento-enamel junction (CEJ)] or unfavorale (non-restorable fractures under CEJ). The obtained data were analyzed using the SPSS version 21.0 statistical software. One-way ANOVA and Tukey's test were used to compare the mean values of maximum load of the four groups. Pearson's Chi-square test was used to compare the distribution of failure mode among the four groups. The p-value of ≤ 0.05 was used to report the statistical significance of results.  相似文献   
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ObjectivesTo describe clinical characteristics and management of acute lymphadenitis and to identify risk factors for complications.MethodsHealth record review of children ≤17 years with acute lymphadenitis (≤2 weeks) in a tertiary paediatric emergency department (2009–2014); 10% of charts were reviewed by a blinded second reviewer. Multivariate logistic regression identified factors associated with intravenous antibiotic treatment, unplanned return visits warranting intervention, and surgical drainage.ResultsOf 1,023 health records, 567 participants with acute lymphadenitis were analyzed. The median age = 4 years (interquartile range [IQR]: 2 to 8 years), and median duration of symptoms = 1.0 day (IQR: 0.5 to 3.0 days). Cervical lymphadenitis was most common. Antibiotics were prescribed in 73.5% of initial visits; 86.9% of participants were discharged home. 29.0% received intravenous antibiotics, 19.3% had unplanned emergency department return visits, and 7.4% underwent surgical drainage. On multivariate analysis, factors associated with intravenous antibiotic use included history of fever (odds ratio [OR]=2.07, 95% confidence interval [CI]: 1.11 to 3.92), size (OR=1.74 per cm, 95% CI: 1.44 to 2.14), age (OR=0.84 per year, 95% CI: 0.76 to 0.92), and prior antibiotic use (OR=4.45, 95% CI: 2.03 to 9.88). The factors associated with unplanned return visit warranting intervention was size (OR=1.30 per cm, 95% CI: 1.06 to 1.59) and age (OR=0.89, 95% CI: 0.80 to 0.97). Factors associated with surgical drainage were age (OR=0.68 per year, 95% CI: 0.53 to 0.83) and size (OR=1.80 per cm, 95% CI: 1.41 to 2.36).ConclusionsThe vast majority of children with acute lymphadenitis were managed with outpatient oral antibiotics and did not require return emergency department visits or surgical drainage. Larger lymph node size and younger age were associated with increased intravenous antibiotic initiation, unplanned return visits warranting intervention and surgical drainage.  相似文献   
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