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81.
ObjectivesThe presence of a wide variety of autoantibodies is a characteristic feature of systemic lupus erythematosus (SLE). Although non-specific, anti-complement C1q (anti-C1q) were shown to correlate with the occurrence of active nephritis. The present study aimed to investigate the prevalence of anti-C1q in Tunisian SLE patients and their association with clinical manifestations, especially renal involvement.Patients and methodsIgG anti-C1q antibodies were assessed by Elisa in 98 SLE patients, 55 patients with rheumatoid arthritis (RA) and 65 healthy individuals (HI).ResultsAnti-C1q were found in 53 (54.1%) patients with SLE, three (5%) patients with RA and six (9.3%) HI. Among the 65 patients with renal involvement, anti-C1q were present in 35 (53.8%) patients. There was no significant association between anti-C1q and renal or extrarenal manifestations. In addition, there was no correlation between anti-C1q titer and SLEDAI index. Anti-C1q were significantly associated with anti-nucleosome (P = 0.001), anti-Sm (P = 0.01) and a low C4 level (P = 0.046). Concomitant presence of anti-C1q and anti-dsDNA antibodies was not associated with renal manifestations.ConclusionOur study shows that prevalence of anti-C1q was comparable with that previously reported in Caucasian populations. These antibodies were associated with a low C4 level. However, there was no association between anti-C1q and renal involvement or severity of nephritis.  相似文献   
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Rebreathing of expired air may be a lethal hazard for prone sleeping infants. This paper describes a mechanical model to simulate infant breathing, and examines the effects of bedding on exhaled air retention. Under simulated rebreathing conditions, the model allows the monitoring of raised carbon dioxide (CO2) inside an artificial lung-trachea system. Resulting levels of CO2 (although probably exaggerated in the mechanical model compared with an infant, due to the model's fixed breathing rate and volume) suggest that common bedding materials vary widely in inherent rebreathing potential. In face down tests, maximum airway CO2 ranged from less than 5% on sheets and waterproof mattresses to over 25% on sheepskins, bean bag cushions, and some pillows and comforters. Concentrations of CO2 decreased with increasing head angle of the doll, away from the face down position. Recreations of 29 infant death scenes also showed large CO2 increases on some bedding materials, suggesting these infants could have died while rebreathing.  相似文献   
84.
The best curative option for locally advanced (stages II–III) squamous-cell carcinomas of the anal canal (SCCAC) is concurrent chemo-radiotherapy delivering 36–45 Gy to the prophylactic planning target volume with an additional boost of 14–20 Gy to the gross tumor volume with or without a gap-period between these two sequences. Although 3-dimensional conformal radiotherapy led to suboptimal tumor coverage because of field junctions, this modality remains a standard of care. Recently, intensity-modulated radiotherapy (IMRT) techniques improved tumor coverage while decreasing doses delivered to organs at risk. Sparing healthy tissues results in fewer severe acute toxicities. Consequently, IMRT could potentially avoid a gap-period that may increase the risk of local failure. Furthermore, these modalities reduce severe late toxicities of the gastrointestinal tract as well as better functional conservation of anorectal sphincter. This report aims to critically review contemporary trends in the management of locally advanced SCCAC using IMRT and concurrent chemotherapy.  相似文献   
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Background: Curcumin was shown to reduce epithelial-mesenchymal transition (EMT) markers in previous shortterm studies. This study was aimed to investigate the potential of curcumin in the prevention of EMT activation inMCF-7 cells induced by endoxifen. Methods: MCF-7 breast cancer cells were treated with Endoxifen 1000 nM+betaestradiol1 nM with or without curcumin (8.5μM or 17 μM). Cells treated with dimethyl sulfoxide (DMSO) 0.001%were used as negative control. After 8 weeks of continuous treatment, the cells were counted, analyzed for mRNAE-cadherin, vimentin, TGF-β expression, total reactive oxygen species (ROS) and observed for morphological changesusing confocal microscope and transmission electron microscope. Result: MCF-7 cell viability was increased inendoxifen + β-estradiol group. Cell viability was significantly decreased in curcumin 17 μM, but not in curcumin8.5 μM group. Analysis of EMT markers at week 8 indicates that there were increase in vimentin and TGF-β mRNAexpressions, while E-cadherin mRNA expressions and TGF-β1 protein concentrations were shown to decrease. Theresults showed that administration of curcumin in all the dose administered were incapable improving the expressionsof vimentin, TGF-β1 and E-cadherin. There was a decrease in ROS concentration in curcumin treated cells (8.5 μM)while in curcumin 17 μM, ROS concentration was increased. Morphological observation using confocal microscopeand TEM showed the presence of mesenchymal cells and adherens junction. Conclusion: endoxifen treatments foreight weeks resulted in upregulation of EMT markers and changes in morphology of MCF-7 breast cancer cells. Theaddition of curcumin did not prevent the activation of EMT.  相似文献   
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88.
Overview on SARS in Asia and the World   总被引:1,自引:0,他引:1  
Severe Acute Respiratory Syndrome (SARS) is the first major novel infectious disease to hit the international community in the 21st century. It originated in southern China in November 2002, reached Hong Kong in February 2003 and spread rapidly thereafter to 29 countries/regions on five continents. At the end of the epidemic, the global cumulative total was 8098 with 774 deaths. Seven Asian countries/regions were among the top ten on the list. Mainland China and Hong Kong, SAR, accounted for 87% of all cases and 84% of all deaths. Severe acute respiratory syndrome is caused by a novel coronavirus. It has alarmed the world with its infectivity and significant morbidity and mortality, its lack of a rapid, reliable diagnostic test and lack of effective specific treatment and vaccination. The adverse impact on travel and business around the world, particularly in Asia, has been enormous.
Some lessons learnt from this epidemic included: (1) any outbreak of infectious disease can rapidly spread around the world by air travel; (2) early reporting of the outbreak to neighbouring countries/regions and the World Health Organization is essential to prevent international spread; and (3) infection control, tracing and quarantine of contacts are essential to control the epidemic. Many questions remain unanswered, including the origin and pathogenesis of the novel coronavirus, the natural history and the best specific treatment of the disease. The SARS-CoV has probably jumped from an animal host to humans. There is an urgent need to evaluate the human–animal habitat in southern China and to remove animal reservoirs if found.  相似文献   
89.
Arterial switch for repair of transposition of the great arteries was performed on 53 patients since October 1983. These patients were divided into three groups: group I, 25 infants with an intact ventricular septum who had primary repair in the first month of life (2 to 34 days of age, mean 9.7 +/- 6.6); group II, 13 patients with an intact ventricular septum who had anatomic repair after a preliminary procedure (pulmonary artery banding in 13, shunt in 10, atrial septectomy in 1); and group III, 15 infants with transposition of the great arteries and ventricular septal defect. In group III, six patients had Taussig-Bing abnormality, nine had previous pulmonary artery banding, three had coarctation of the aorta repaired earlier in life, and four were less than 2 weeks old. Overall early mortality was 9.4% (5/53: group I 8%, group II 7.6%, group III 13.3%). Two late deaths occurred in group II 10 and 12 weeks postoperatively after infection and high fever. A third late death 18 weeks postoperatively was due to aspiration in an infant with Goldenhar's syndrome. Mortality and morbidity decreased significantly after an initial learning period (no deaths from July 1985 to March 1987 overall, and none in the last 15 infants operated on in group I). The surviving 45 patients are doing well. All have normal sinus rhythm. Two had transient asymptomatic arrhythmias. Left and right ventricular function assessed by echocardiogram and postoperative cardiac catheterization were within normal ranges in all but two patients, one with pulmonary artery stenosis and one (Taussig-Bing abnormality with two large ventricular septal defects) with severe pulmonary vascular disease (9.6 units) observed before anatomic repair. The right ventricular pressure at catheterization ranged from 27 to 42 mm Hg in 12 patients and was 55 mm Hg in two. There was no aortic stenosis. Aortic insufficiency was trivial in three patients and mild in one. We conclude that excellent results can be obtained with arterial switch for transposition of the great arteries with or without ventricular septal defect, especially in neonates.  相似文献   
90.
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