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排序方式: 共有377条查询结果,搜索用时 15 毫秒
91.
Toppila-Salmi SK Myller JP Torkkeli TV Muhonen JV Renkonen JA Rautiainen ME Renkonen RL 《American journal of respiratory and critical care medicine》2005,171(12):1350-1357
RATIONALE: Chronic rhinosinusitis is characterized by persistent inflammation of the nasal and paranasal mucosa with numerous emigrated leukocytes. L-selectin on leukocytes and its endothelial glycosylated ligands initiate organ-specific leukocyte infiltration into inflamed tissues. OBJECTIVES: The purpose of this study was to evaluate the endothelial expression of functionally active endothelial L-selectin ligands, sulfated sialyl Lewis x, in maxillary sinus mucosa from patients with chronic rhinosinusitis and from normal control subjects. METHODS: Maxillary sinus mucosa specimens (116) were obtained surgically and immunohistochemically stained with monoclonal antibodies detecting sialyl Lewis x or sulfated extended core 1 lactosamines. The severity of the inflammation was determined by intraoperative endoscopic findings, computed tomography scans, and histopathologic assessment of the specimens. MEASUREMENTS AND MAIN RESULTS: The percentage of vessels expressing endothelial sulfated sialyl Lewis x epitopes increased during chronic rhinosinusitis compared with uninflamed control tissue, especially in patients with additional allergic rhinitis, and decreased in specimens from aspirin-intolerant patients with preoperative oral corticosteroid treatment. In addition, the expression level of endothelial sulfated sialyl Lewis x epitopes and the number of mucosal eosinophils correlated with the severity of the inflammation, and decreased in specimens taken 9 months postoperatively compared with intraoperative samples, especially in patients with intranasal corticosteroid treatment. CONCLUSIONS: Our results suggest that functionally active L-selectin ligands might guide leukocyte traffic into maxillary sinus mucosa preferentially in patients with severe findings of chronic maxillary rhinosinusitis, thus leading to aggravation of the inflammation. 相似文献
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93.
Karvonen J Kauma H Kervinen K Ukkola O Rantala M Päivänsalo M Savolainen MJ Kesäniemi YA 《Journal of hypertension》2002,20(12):2371-2378
OBJECTIVE: Smoking is a risk factor for increased carotid artery intima-media thickness (IMT). The apolipoprotein E (apoE) 4 allele has been associated with cardiovascular diseases, but the role of apoE in regard to intima-media thickness (IMT) has remained controversial. The objective was to investigate whether there is some gene-environment interaction between smoking and apoE polymorphism.DESIGN Cross-sectional case-control study. METHODS: IMTs of 511 hypertensive and control men were measured ultrasonographically and the apoE genotypes were determined. Genotypes with the 4 allele were pooled into one group and the genotypes without it into another. RESULTS: A significant interaction between the 4 allele and smoking affecting IMT was observed among the hypertensive smokers, as assessed by analysis of covariance. The mean carotid IMT was significantly greater (1.01 versus 0.90 mm, P = 0.003) in the 4 carriers than in the subjects without 4 among the hypertensive smokers. The number of plaques was also significantly higher. No differences were found in the other subjects (hypertensive non-smokers or controls). Linear regression analysis indicated that the 4 allele was an independent determinant of IMT in the hypertensive smokers but not in the other subjects. The estimated average effect of the 4 allele on the mean IMT in the hypertensive smokers was 0.088 mm (P < 0.001). In the oldest age group, the interaction of smoking and 4 was also seen in the control subjects.CONCLUSION: The findings suggest that the 4 carriers are particularly susceptible to the atherogenic effects of smoking. This interaction is particularly clear in hypertensive subjects. 相似文献
94.
Interleukin-6 and tumor necrosis factor alpha in relation to myocardial infarct size and collagen formation 总被引:7,自引:0,他引:7
Puhakka M Magga J Hietakorpi S Penttilä I Uusimaa P Risteli J Peuhkurinen K 《Journal of cardiac failure》2003,9(4):325-332
BACKGROUND: Interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) levels increase after acute myocardial infarction (AMI) in humans. Experimental data suggest that these cytokines regulate the initiation of scar formation after AMI. We investigated the interrelationships of IL-6 and TNF-alpha, tissue injury, infarct size, cardiac function, and collagen formation in humans. METHODS: Serum and plasma samples were taken on 93 patients receiving thrombolytic treatment for their first AMI. Collagen formation was evaluated by measuring concentrations of serum aminoterminal propeptide of type III procollagen (PIIINP). RESULTS: IL-6 levels increased by 44% (P<.001) and peaked at 24 hours. Peak IL-6 levels correlated positively with area under the curve of creatine kinase MB mass (r=.31, P<.01), peak troponin T level (r=.34, P<.005), and PIIINP measured at discharge (r=.46, P<.001). There were no changes in TNF-alpha levels, and patients with left ventricular dysfunction (EF<40%) had similar TNF-alpha levels as those with preserved left ventricular function. CONCLUSIONS: IL-6 may regulate collagen formation and thus remodeling of the left ventricle after AMI. In addition, TNF-alpha measurement is useless in the assessment of infarct size or left ventricular function during the immediate post-infarction period. 相似文献
95.
J. Arturo Garcia-Horsman Jarkko I. Venäläinen Olli Lohi I. Seppo Auriola Ilma R. Korponay-Szabo Katri Kaukinen 《Scandinavian journal of gastroenterology》2013,48(5):562-571
Objective. Gliadin digestion-resistant peptides are harmful in coeliac disease (CD), and initiate an autoimmune reaction that cause a cascade of symptoms. The role of the endogenous prolyl oligopeptidase (POP) is still not clear, and its activity over gliadin immunoactive peptides has not been fully established. Our objective was therefore to determine the endogenous POP protein level, tissue distribution and total activity in normal and CD epithelia, to evaluate tissue peptidase activity over gliadin peptides, and compare this with activities of mammalian POP and rat intestinal extracts. Material and methods. POP was assayed in biopsy preparations enzymatically and by Western blot analysis. Distribution was studied by immunohistochemistry using a specific POP antibody. Peptide cleavage was followed by mass spectroscopy-high-performance liquid chromatography (MS-HPLC). Results. There was no difference in POP activity between normal and CD samples, but those from active CD subjects had an even higher ability to degrade the 33-mer peptide than those from treated CD and healthy humans. POP locates intracellularly in epithelia, similarly to dipeptidyl peptidase IV (DPPIV), but the latter is clearly found in normal microvilli but less so in diseased microvilli. Mammalian POP is unable to digest 33-mer peptide, which, conversely, is a POP inhibitor. Rat intestine is more effective than human intestine in cleaving the 33-mer peptide. However, the products are still harmful epitopes. A surplus of POP eliminates 12-mer and 19-mer peptide products. Conclusions. The results rule out a causative role of POP in the pathogenesis of CD and strongly suggest that other peptidases are needed to eliminate gliadin-derived, immunoactive and toxic peptides larger than 33-mer, which is a POP inhibitors. 相似文献
96.
Increases in local pressure pain thresholds after muscle exertion in women with chronic shoulder pain 总被引:1,自引:0,他引:1
Persson AL Hansson GA Kalliomäki J Sjölund BH 《Archives of physical medicine and rehabilitation》2003,84(10):1515-1522
OBJECTIVE: To examine the relation between muscular tenderness and local muscular fatigue. DESIGN: Before-after trial, measuring pressure pain thresholds and signs of local muscular fatigue by using surface electromyography before, after, 10 minutes after, and 20 minutes after intervention. SETTING: University rehabilitation department in Sweden. PARTICIPANTS: Nineteen female hospital cleaners with unilateral chronic shoulder pain for 1 year. No previous trauma, surgery, or signs of systemic or neurologic disease. INTERVENTION: Static abduction endurance test with submaximal unilateral activation of the trapezius and deltoid muscles. MAIN OUTCOME MEASURES: Pressure pain thresholds and electromyographic fatigue parameters (root mean square [RMS]; mean power frequency [MPF]). RESULTS: Mean normalized pressure pain threshold values increased significantly (95% confidence interval [CI]) and lasted for 20 minutes: in the trapezius, threshold values increased to 115% to 120% (95% CI, 100%-140%; P=.04-.05); and in the deltoid, the threshold increased to 112% to 115% (95% CI, 100%-130%; P=.02-.05). Development of significant electromyographically defined fatigue was seen: in the trapezius, the RMS increased to 130% (95% CI, 119%-141%), and in the deltoid, the MPF decreased to 78% (95% CI, 74%-82%), but normalized within 15 seconds to 10 minutes. CONCLUSION: Lasting bilateral increases in pressure pain thresholds but transient local muscular fatigue were seen after a unilateral static endurance test. The sensitivity of the sensory nervous system may change during a static muscle contraction and sometimes contributes to a localized sensation of numbness. 相似文献
97.
Eero Rissanen Jouni Tuisku Pauliina Luoto Eveliina Arponen Jarkko Johansson Vesa Oikonen Riitta Parkkola Laura Airas Juha O Rinne 《Journal of cerebral blood flow and metabolism》2015,35(1):157-165
[11C]TMSX ([7-N-methyl-11C]-(E)-8-(3,4,5-trimethoxystyryl)-1,3,7-trimethylxanthine) is a selective adenosine A2A receptor (A2AR) radioligand. In the central nervous system (CNS), A2AR are linked to dopamine D2 receptor function in striatum, but they are also important modulators of inflammation. The golden standard for kinetic modeling of brain [11C]TMSX positron emission tomography (PET) is to obtain arterial input function via arterial blood sampling. However, this method is laborious, prone to errors and unpleasant for study subjects. The aim of this work was to evaluate alternative input function acquisition methods for brain [11C]TMSX PET imaging. First, a noninvasive, automated method for the extraction of gray matter reference region using supervised clustering (SCgm) was developed. Second, a method for obtaining a population-based arterial input function (PBIF) was implemented. These methods were created using data from 28 study subjects (7 healthy controls, 12 multiple sclerosis patients, and 9 patients with Parkinson''s disease). The results with PBIF correlated well with original plasma input, and the SCgm yielded similar results compared with cerebellum as a reference region. The clustering method for extracting reference region and the population-based approach for acquiring input for dynamic [11C]TMSX brain PET image analyses appear to be feasible and robust methods, that can be applied in patients with CNS pathology. 相似文献
98.
Iron-doped tetrahedral amorphous carbon thin films (Fe/ta-C) were deposited with varying iron content using a pulsed filtered cathodic vacuum arc system (p-FCVA). The aim of this study was to understand effects of iron on both the physical and electrochemical properties of the otherwise inert sp3-rich ta-C matrix. As indicated by X-ray photoelectron spectroscopy (XPS), even ∼0.4 at% surface iron had a profound electrochemical impact on both the potential window of ta-C in H2SO4 and KOH, as well as pseudocapacitance. It also substantially enhanced the electron transport and re-enabled facile outer sphere redox reaction kinetics in comparison to un-doped ta-C, as measured with electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) using outer-sphere probes Ru(NH3)6, IrCl6, and FcMeOH. These increases in surface iron loading were linked to increased surface oxygen content and iron oxides. Unlike few other metals, an iron content even up to 10 at% was not found to result in the formation of sp2-rich amorphous carbon films as investigated by Raman spectroscopy. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) investigations found all films to be amorphous and ultrasmooth with Rq values always in the range of 0.1–0.2 nm. As even very small amounts of Fe were shown to dominate the electrochemistry of ta-C, implications of this study are very useful e.g. in carbon nanostructure synthesis, where irregular traces of iron can be readily incorporated into the final structures.Surface iron levels as low as 0.4 at% (XPS) can considerably change the electrochemical properties of initially inert carbon surfaces. 相似文献
99.
100.