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1.
Exhaled breath condensate (EBC) provides a noninvasive means of sampling the lower respiratory tract. Collection of EBC might be useful in the assessment of airway oxidative stress in smokers. The aim of this study was to determine 8-isoprostane and hydrogen peroxide levels in EBC, and, in addition, to investigate the reproducibility of these measurements. EBC samples were collected from 12 healthy male smokers at three time points within 1 week. 8-isoprostane and H2O2 were measured in nonconcentrated EBC using immunochemical and colorimetric assays, respectively. 8-isoprostane and H2O2 were detected in only 36 and 47% of all EBC samples, respectively. It was not possible to calculate the within-subject variation in a reliable manner since only three of the 12 smokers exhibited detectable 8-isoprostane concentrations on all three occasions (mean 4.6 pg x mL(-1); range 3.9-7.7 pg x mL(-1)), whereas H2O2 could not be detected on all three occasions in any of the smokers. Spiking experiments revealed a recovery of 83.5-109.5% for 8-isoprostane and 69.9-129.0%, for H2O2 in fresh EBC samples. It was concluded that levels of 8-isoprostane and hydrogen peroxide cannot be reproducibly assessed in exhaled breath condensate from healthy smokers because of their low concentration and/or the lack of sensitivity of the available assays.  相似文献   
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Intima formation in vessels, spontaneous or experimentally induced, is generally characterized by the presence of longitudinally orientated smooth muscle cells (LSMC). During an experiment of neo-intima induction in carotid arteries in rabbits, by application of a nonconstrictive silastic cuff, a study was performed to investigate the presence of LSMC in the systemic and pulmonary circulations, in both elastic and muscular arteries. Three patterns could be distinguished: intimai cushions in muscular arteries, single or small groups of LSMC in the intima in elastic and larger muscular arteries, and intra-medially located layers or columns of LSMC in the aorta, the pulmonary artery, at the bifurcation of the aorta and around orifices of branches. In order to understand this peculiar orientation a biomechanical approach was used: this showed that near the lumen the circumferential stress is 4.5 times higher than the longitudinal. Because the cell surface of the smooth muscle cells exposed to this stress per unit vessel length is much less in the longitudinal than in the circular direction we conclude that the LSMC align in the direction which allows them to cope most effectively with the mechanical stresses.  相似文献   
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Multiple exostoses represent a genetically heterogeneous disorder that may occur isolated or as part of a complex contiguous gene syndrome such as Langer-Giedion syndrome on chromosome 8 and the proximal 11p deletion syndrome on chromosome 11. Here we describe a boy with multiple exostoses, hypertrichosis, mental retardation, and epilepsy due to a de novo deletion on chromosome 8q24. Molecular analysis revealed that the deletion interval overlaps with the Langer-Giedion syndrome and involves the EXT1 gene and additional genes located distal to EXT1, but probably not encompassing the TRPS1 gene located proximal to EXT1.  相似文献   
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D. Wuyts 《Phytothérapie》2012,10(2):117-120
Outre un apport nutritionnel non négligeable, la feuille de persil s’avère antiradicalaire et alcalinisante. Particulièrement utile à la digestion, le persil intervient dans la détoxication et peut s’avérer utile au pléthorique, à la chimio prévention ou à la femme. On en limitera l’apport en cas de traitement par antivitamine K, de prise de barbiturique ou d’antalgique ou en cas de cancer du sein estrogénodépendant.  相似文献   
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Objectives:To determine whether the revised 2018 ATS/ERS/JRS/ALAT radiological criteria for usual interstitial pneumonia (UIP) provide better diagnostic agreement compared to the 2011 guidelines.Methods:Cohort for this cross-sectional study (single center, nonacademic) was recruited from a multidisciplinary team discussion (MDD) from July 2010 until November 2018, with clinical suspicion of fibrosing interstitial lung disease (n= 325). Exclusion criteria were technical HRCT issues, known connective tissue disease (rheumatoid arthritis, systemic sclerosis, poly-or dermatomyositis), exposure to pulmonary toxins or lack of working diagnosis after MDD. Four readers with varying degrees in HRCT interpretation independently categorized 192 HRCTs, according to both the previous and current ATS/ERS/JRS/ALAT radiological criteria. An inter-rater variability analysis (Gwet’s second-order agreement coefficient, AC2) was performed.Results:The resulting Gwet’s AC2 for the 2011 and 2018 ATS/ERS/JRS/ALAT radiological criteria is 0.62 (±0.05) and 0.65 (±0.05), respectively. We report only minor differences in agreement level among the readers. Distribution according to the 2011 guidelines is as follows: 57.3% ‘UIP pattern’, 24% ‘possible UIP pattern’, 18.8% ‘inconsistent with UIP pattern’ and for the 2018 guidelines: 59.6% ‘UIP’, 14.5% ‘probable UIP’, 15.9% ‘indeterminate for UIP’ and 10% ‘alternative diagnosis’.Conclusions:No statistically significant higher degree of diagnostic agreement is observed when applying the revised 2018 ATS/ERS/JRS/ALAT radiological criteria for UIP compared to those of 2011. The inter-rater variability for categorizing the HRCT patterns is moderate for both classification systems, independent of experience in HRCT interpretation. The major advantage of the current guidelines is the better subdivision in the categories with a lower diagnostic certainty for UIP.Advances in knowledge:- In 2018, a revision of the 2011 ATS/ERS/JRS/ALAT radiological criteria for UIP was published, part of diagnostic guidelines for idiopathic pulmonary fibrosis.- The inter-rater agreement among radiologist is moderate for both classification systems, without a significantly higher degree of agreement when applying the revised radiological criteria.  相似文献   
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Sarcoidosis is a multisystem disorder of unknown cause with a highly variable course. Corticosteroids are considered the standard agent for treatment, however there is no consensus about when and in whom therapy should be initiated, what dose should be given and for how long. There seems to be a limited benefit on chest radiographic findings, forced vital capacity and diffusing capacity. The evidence supporting the disease-modulating effect is limited. Cytotoxic agents are often used as steroid-sparing in patients requiring chronic therapy, however there are only little randomized controlled trials to support their use and side effects are common. Tumour necrosis factor-a is thought to be crucial in the development of the typical granulomas in sarcoidosis. Many case reports and case series suggest that specific therapy targeted against this cytokine is very effective. Despite these promising results, only limited evidence is found in multicenter randomized controlled trials.  相似文献   
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Aims Biochemical marker testing has improved the evaluation and management of patients with cardiovascular diseases over the past decade. Natriuretic peptides (NPs), used in clinical practice to assess cardiac dysfunction, exhibit many limitations, however. We used an unbiased proteomics approach for the discovery of novel diagnostic plasma biomarkers of heart failure (HF). Methods and results A proteomics pipeline adapted for very low-abundant plasma proteins was applied to clinical samples from patients admitted with acute decompensated HF (ADHF). Quiescin Q6 (QSOX1), a protein involved in the formation of disulfide bridges, emerged as the best performing marker for ADHF (with an area under the receiver operator characteristic curve of 0.86, 95% confidence interval: 0.79-0.92), and novel isoforms of NPs were also identified. Diagnostic performance of QSOX1 for ADHF was confirmed in 267 prospectively collected subjects of whom 76 had ADHF. Combining QSOX1 to B-type NP (BNP) significantly improved diagnostic accuracy for ADHF by particularly improving specificity. Using thoracic aortic constriction in rats, QSOX1 was specifically induced within both left atria and ventricles at the time of HF onset. Conclusion The novel biomarker QSOX1 accurately identifies ADHF, particularly when combined with BNP. Through both clinical and experimental studies we provide lines of evidence for a link between ADHF and cardiovascular production of QSOX1.  相似文献   
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