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51.
To investigate respiratory symptoms, increased bronchial responsiveness, and signs of airway inflammation in elite swimmers, we examined 29 swimmers from the Finnish national team and 19 healthy control subjects (nonasthmatic, symptom-free). They answered a questionnaire and were interviewed for respiratory symptoms. Lung volumes were measured and bronchial responsiveness assessed by a histamine challenge test. Induced sputum samples were also collected. Fourteen (48%) of the swimmers and three (16%) of the control subjects showed increased bronchial responsiveness (P<0.05). The sputum cell differential counts of eosinophils (mean 2.7% vs 0.2%) and neutrophils (54.7% V5 29.9%) from swimmers were significantly higher than those from controls (P<0.01). Eosinophilia (sputum differential eosinophil count of >4%) was observed in six (21%) of the swimmers and in none of the controls (P<0.05). Symptomatic swimmers had significantly more sputum eosinophils than did the symptom-free. The concentrations of sputum eosinophil peroxidase (EPO) and human neutrophil lipocalin (HNL) were significantly higher in swimmers than control subjects (P<0.001 and P=0.05). We conclude that elite swimmers had significantly more often increased tjronchial responsiveness than control subjects. Sputum from swimmers contained a higher percentage of eosinophils and neutrophils, and higher concentrations of EPO and HNL than sputum from controls. Long-term and repeated exposure to chlorine compounds in swimming pools during training and competition may contribute to the increased occurrence of bronchial hyperresponsiveness and airway inflammation in swimmers.  相似文献   
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BackgroundAlthough preoperative anemia has been suggested to predict postsurgical morbidity and mortality among infants < 1 year of age, the data were drawn from heterogeneous patient cohorts including severely ill infants undergoing complex, high-risk procedures. We aimed to determine whether untreated preoperative anemia was associated with increased risk of postoperative complications in infants < 1 year of age who underwent pyloromyotomy, a common and relatively simple surgery.MethodsInfants < 1 year of age undergoing pyloromyotomy were identified from the American College of Surgeons (ACS) National Surgical Quality Improvement Program-Pediatric database. Preoperative anemia was defined as a hematocrit ≤ 40% for infants 0–30 days of age and ≤ 30% for infants more than 30 days of age. Patients who received pre- or postoperative blood transfusions were excluded.ResultsWe identified 2948 patients who met our inclusion criteria, of whom 843 were anemic (29%). The overall rate of complications in this cohort was 6%. The most common postoperative complications were readmission (97 cases), surgical site infection (43), reoperation (39), prolonged hospital stay (24), urinary tract infection (3), 30-day mortality (3) and cardiac arrest (2). We found no differences in the incidence of complications in anemic versus nonanemic patients on bivariate analysis or multivariable logistic regression (adjusted odds ratio = 1.2; 95% confidence interval: 0.8–1.7; P = 0.319).ConclusionsIn relatively healthy infants undergoing pyloromyotomy, untreated preoperative anemia was not associated with postoperative compilations and should not be considered a significant risk factor.Level of evidence III.  相似文献   
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Background: P-glycoprotein (Pgp), encoded by the multidrug resistance 1 (MDR1) gene, is an efflux transporterwhich plays an important role in pharmacokinetics. The current preliminary study was designed to determineassociations between a germ-line polymorphism in the MDR1 gene with differentiated thyroid carcinoma (DTC).Materials and Methods: In the current case-control study, 60 differentiated thyroid cancers (DTC)- 45 papillaryTC (PTC), 9 follicular TC(FTC) and 6 well-differentiated tumors of uncertain malignant potential (WDT-UMP)were examined. Results were compared to a healthy control group (n=58) from the same population. GenomicDNA was extracted from peripheral blood with EDTA and the target gene was genotyped by real-time PCR.Results: Carriers of the variant allele of MDR1 exon 26 polymorphism were at 2.8-fold higher risk of DTC thanthe control group (odds ratio [OR]: 0.3805, 95% confidence interval [Cl]: 0.1597-0.9065 (p> 0.046). Conclusions:Presented results suggest that the MDR1 3435TT genotype might influence risk of development of DTC andthat the CC genotype might be linked to a poor prognosis. Large-scale studies are now needed to validate thisassociation.  相似文献   
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皮肤扩张面积测算的研究及临床应用   总被引:4,自引:0,他引:4  
目的探讨使用扩张器进行注水扩张的过程中,注水量与扩张面积之间的关系,解决临床上扩张面积增加的测算问题。方法将扩张器埋于狗的头、胸及背部皮下组织内,每次注水后拍摄云纹照片,测量扩张的面积。结果通过云纹照片获得的32个数据,进行线性回归分析,得出公式,A=0.152v-0.151(A为扩张皮肤的表面积增加,V为获得此表面积增加的注水总量)。结论此公式应用于临床,高标率(高于标准注水量的比率)达70.6%,有临床应用参考价值。  相似文献   
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Objective  We investigated the application of high-resolution microarray-based comparative genomic hybridisation (array CGH) on a fetus showing increased nuchal translucency (NT).
Design  Case study.
Setting  Tertiary referral obstetrics unit.
Sample  Pregnant woman attended the antenatal clinic.
Methods  Conventional karyotyping and genetic test was carried out for the alpha-globin gene. High-resolution array CGH using the high-density 244K Agilent microarray was performed on fetal blood sample by cordocentesis to investigate the possibility of any genomic imbalance.
Main outcome measures  Detection of chromosomal abnormality.
Results  Karyotyping analysis showed 46,XY. Molecular genetic diagnosis confirms the fetus has Hb-H constant spring disease but cannot explain the increased NT to 3.2 mm. Array CGH analysis discovered a 1.32-Mb microdeletion on chromosome 16p13.11. Deletion at 16p13.11 has been implicated to predispose to autism and/or mental retardation. Baby was delivered at 40 weeks of gestation, and follow up was carried out at 3 months of age without sign of mental retardation/developmental delay.
Conclusions  This case study demonstrated that array CGH can accurately calibrate the size and identify de novo interstitial chromosome imbalances. However, the presence of chromosome copy variants with unknown clinical significance currently limits its wider scale application in prenatal diagnosis and needs further investigations.  相似文献   
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Objective:To study the relationship between plasma treatment time acrylic resin denture material in the size of 2 mm × 10 mm × 10 mm. and efficacy. Methods:Test specimens were prepared from an Plasma treatment was carried out on the surface of Polymethyl methacrylate(PMMA) at different time. XPS studies, IR spectra studies and measurement of wetting angle were performed. Results: XPS showed the peak corresponding to C-O getting higher as the treatment proceeded, however at 120 seconds, the peak did not increase any longer and partly crossed with the peak at the duration of 60 seconds. IR spectra showed the wave corresponding to C-H was reduced as O2-plasma treatment proceeded, and then changed little, Wetting angle initially decreased dramatically, however, as the reaction proceeded, wetting angle increased slightly. Conclusion:Equilibrium was reached for introducing oxygen-containing groups and changing of C-H. As the treatment proceeded, wetting angle increased slightly.  相似文献   
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