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71.
Sporea I Badea R Sirli R Lupsor M Popescu A Danila M Focsa M Deleanu A 《Hepatitis monthly》2011,11(7):532-538
Background
In chronic liver diseases, a correct estimation of the severity of liver fibrosis is important for recommendations regarding the treatment. Nowadays, evaluation of fibrosis is done by noninvasive methods such as biochemical scores and transient elastography instead of liver biopsy. The lack of sensitivity to detect fibrosis, because of its heterogeneity is a drawback of liver biopsy (LB).Objectives
To compare transient elastography (TE) and acoustic radiation force impulse (ARFI) for the evaluation of liver stiffness (LS), against percutaneous LB.Patients and Methods
Our study comprised of 223 subjects; 52 without fibrosis (38 volunteers and 14 patients with F0 on LB), 36 with F1, 40 with F2, 26 with F3 and 69 with liver cirrhosis (46 with LB and 23 with signs of cirrhosis). For each patient we performed in the same session 10 TE and 5 ARFI measurements. The median values were calculated.Results
A strong linear correlation (Spearman rho = 0.870) was found between TE and fibrosis (P < 0.0001); there was also a weaker correlation between ARFI and fibrosis (Spearman rho = 0.646; P < 0.0001). TE measurements were also correlated with ARFI measurements (Spearman rho = 0.733, P < 0.0001). The best test for predicting significant fibrosis (F ≥ 2) was TE with a cut-off value of 7.1 kPa (AUROC 0.953). For ARFI, the cut-off value was 1.27 m/s-area under ROC curve (AUROC): 0.890, sensitivity (Se) of 88.7%, specificity (Sp) of 67.5%, positive predictive value (PPV) of 64.5%, and negative predictive value (NPV) of 90% (P = 0.0044). For predicting cirrhosis (F = 4), the optimum cut-off values were 14.4 kPa for TE (AUROC: 0.985, Se: 95.6%, Sp: 94.7%, PPV: 89.2%, NPV: 98%) and 1.7 m/s for ARFI (AUROC: 0.931, Se: 93%, Sp: 86.7%, PPV: 73.6%, NPV: 96.9%) (P = 0.0102).Conclusions
LS evaluation by means of ARFI is not superior to TE for the assessment of liver fibrosis. ARFI is an accurate test for the diagnosis of cirrhosis. 相似文献72.
Mirela Dobre Sevag Demirjian Ashwini R. Sehgal Sankar D. Navaneethan 《International urology and nephrology》2011,43(1):175-184
Background
Hepatorenal syndrome (HRS) is a common complication in patients with cirrhosis or fulminant liver failure. We systematically reviewed the benefits and harms of using terlipressin, a novel vasoconstricting agent in patients with HRS. 相似文献73.
74.
Leína Z. Tagawa MD Mirela F. De Almeida MD Antonio Augusto Lopes MD 《Congenital heart disease》2009,4(2):96-102
Background and Purpose. There has been a lot of debate about the use of predicted oxygen consumption to calculate pulmonary vascular resistance using the Fick principle. We therefore comparatively analyzed predicted oxygen consumption in infants and children in specific age groups, using different methods (formulas), as an attempt to better understand the usefulness and limitations of predictions. Methods and Results. Four models (LaFarge & Miettinen, Bergstra et al., Lindahl, and Lundell et al.) were used to predict oxygen consumption in 200 acyanotic patients with congenital cardiac defects aged 0–2.0, >2.0–4.0, >4.0–6.0, and >6.0–8.75 years (median 2.04 years). Significant differences were observed between the age groups (P < .001) and between the methods (P < .001), not related to diagnoses. Differences between methods were more impressive in the first age group (P < .01). In patients aged 0–2.0 years, the lowest values of oxygen consumption (corresponding to the highest estimates of pulmonary vascular resistance) were obtained with the method of Lindahl; above this age, any method except that of Lundell et al. Conclusions. Although measuring oxygen consumption is always preferable, a rational use of predictions, using different methods, may be of help in situations where measurements are definitely not possible. 相似文献
75.
Shinohara MS Yamauti M Inoue G Nikaido T Tagami J Giannini M de Goes MF 《Dental materials journal》2006,25(3):545-552
This study evaluated the influence of a fluoride-containing adhesive on microtensile bond strength (microTBS) to dentin, as well as analyzed the dentin-adhesive interface after acid-base challenge. Experimental groups were: G1--Clearfil SE Bond control (SE); G2--Clearfil Protect Bond control (PB); G3--Primer[SE]/Adhesive[PB]; G4--Primer[PB]/Adhesive[SE]. For microTBS evaluation, dentin surfaces were ground, bonded, and composite resin crowns were built up to obtain beams to be tested. For interfacial analysis, adhesive system was applied on dentin surface and a low-viscosity resin was placed between two dentin disks. Then, the specimens were subjected to acid-base challenge, sectioned, and polished to be observed by SEM. microTBS data showed no statistical differences among the groups (GI: 51.3, G2: 47.6, G3: 55.0, G4: 53.9; mean in MPa). Through SEM, it was observed that a thick acid-base resistant zone adjacent to the hybrid layer was created only when the fluoride-releasing adhesive was used. In conclusion, the presence of fluoride in an adhesive contributed significantly to preventing secondary caries, and did not interfere with dentin-adhesive bond strength. 相似文献
76.
Mirela Sanae Shinohara Marcelo Tavares de Oliveira Vinícius Di Hipólito Marcelo Giannin Mario Fernando de Goes 《Journal of applied oral science : revista FOB》2006,14(6):427-435
Objective:
Although self-etching bonding systems (SES) are indicated to prepare dental enamel for bonding, concerns have been expressed regarding their effectiveness. The aim of this study was to analyze the etching pattern (EP) of nine SES in comparison with 35% and 34% phosphoric acid etchants (FA) on intact (IN) and ground (GR) enamel surface.Materials and Methods:
Twenty-two human third molars were sectioned in mesial-distal and buccal-lingual directions, and four dental fragments were obtained from each tooth. Half of the fragments were ground using 600-grit SiC paper and the other half remained intact. The fragments were randomly assigned into 22 groups, according to the texture of enamel surface (IN and GR) and the technique to etch the enamel (34% FA, 35% FA, AdheSE primer; Brush & Bond; Clearfil Protect Bond primer; iBond; One-up Bond F; OptiBond Solo Plus primer; Tyrian SPE primer; Unifil Bond primer and Xeno III). Conditioners were applied to IN and GR enamel surfaces, according to the manufacturer''s instructions. Specimens etched with phosphoric acids were washed with water, while the surfaces treated with SES were submitted to alternate rinsing with alcohol and acetone. The specimens were dried, sputter-coated and examined under a scanning electron microscope.Results:
For both IN and GR enamel surfaces, the EP of 34 and 35% FA was deeper and more homogeneous in comparison to EP of SES, except for Tyrian SPE. The acidic monomer action of self-etching systems was more effective on GR enamel.Conclusion:
Most of the SES are less aggressive than phosphoric acid etchants and their etching effects were reduced on intact enamel surfaces. Uniterms: Dental acid etching; Dental enamel; Electron microscopy. 相似文献77.
Viral determinants for overcoming Pisum sativum recessive resistance, sbm-2, against the potyvirus Pea seed-borne mosaic virus (PSbMV) were identified in the region encoding the N-terminal part of the P3 protein. Codons conserved between sbm-2 virulent isolates in this region: Q21, K30 and H122 were found to specifically impair sbm-2 virulence when mutated in selected genetic backgrounds. The corresponding amino acids, Gln21 and Lys30, are neighbored by P3 residues strongly conserved among potyviruses and His122 is conserved particularly in potyviral species infecting legumes. The strongest selective inhibition of sbm-2 virulence, however, was observed by elimination of isolate specific length polymorphisms also located in the N-terminal part of the P3 protein. Length variation in N-terminal P3 is common between potyviral species. However, intra-species length polymorphism in this region was found only among PSbMV isolates. Our findings comply with a model for PSbMV pathotypes having evolved by a diversification of the P3 protein likely to extend to the level of function. 相似文献
78.
A nucleoporin is required for induction of Ca2+ spiking in legume nodule development and essential for rhizobial and fungal symbiosis 下载免费PDF全文
Kanamori N Madsen LH Radutoiu S Frantescu M Quistgaard EM Miwa H Downie JA James EK Felle HH Haaning LL Jensen TH Sato S Nakamura Y Tabata S Sandal N Stougaard J 《Proceedings of the National Academy of Sciences of the United States of America》2006,103(2):359-364
Nuclear-cytoplasmic partitioning and traffic between cytoplasmic and nuclear compartments are fundamental processes in eukaryotic cells. Nuclear pore complexes mediate transport of proteins, RNAs and ribonucleoprotein particles in and out of the nucleus. Here we present positional cloning of a plant nucleoporin gene, Nup133, essential for a symbiotic signal transduction pathway shared by Rhizobium bacteria and mycorrhizal fungi. Mutation of Nup133 results in a temperature sensitive nodulation deficient phenotype and absence of mycorrhizal colonization. Root nodules developing with reduced frequency at permissive temperatures are ineffective and electron microscopy show that Rhizobium bacteria are not released from infection threads. Measurement of ion fluxes using a calcium-sensitive dye show that Nup133 is required for the Ca2+ spiking normally detectable within minutes after application of purified rhizobial Nod-factor signal molecules to root hairs. Localization of NUP133 in the nuclear envelope of root cells and root hair cells shown with enhanced yellow fluorescent protein fusion proteins suggests a novel role for NUP133 nucleoporins in a rapid nuclear-cytoplasmic communication after host-plant recognition of symbiotic microbes. Our results identify a component of an intriguing signal process requiring interaction at the cell plasma membrane and at intracellular nuclear and plastid organelle-membranes to induce a second messenger. 相似文献
79.
80.
Matokanović M Rumora L Popović-Grle S Čepelak I Čulić O Barišić K 《Clinical biochemistry》2012,45(10-11):770-774
ObjectiveTo test for possible association of hsp70-2 (+ 1267A/G), hsp70-hom (+ 2437T/C), HMOX-1 (number of GT repeats) and TNF-α (+ 489G/A) polymorphisms with chronic obstructive pulmonary disease (COPD) in Croatian population.MethodsGenotyping of DNA isolated from whole blood of 130 COPD patients (as defined by spirometry) and 95 healthy controls was performed. Fragment size analysis upon restriction enzyme digestion and/or sequencing was used for genotype/allele definition. Significance of findings was tested using χ2 test.Resultshsp70-2 (+ 1267A/G) polymorphism was significantly associated with COPD. Results of genotyping analysis indicated that a genotype carrying G allele was preferentially associated with COPD; odds ratio (OR) = 1.50, 95% confidence interval (CI) = 1.00–2.24 and P = 0.061. OR for the GG genotype was 3.47 with CI = 1.26–9.56 and P = 0.04. No association for hsp70-hom (+ 2437T/C), TNF-α (+ 489G/A) and HMOX-1 (number of GT repeats) polymorphisms were found. In addition, comparison of genotype frequencies among different stages of disease severity (GOLD II-IV) revealed no discrimination for any of the tested polymorphisms.ConclusionThis study is supporting the association of hsp70-2 (+ 1267A/G) polymorphism and COPD. Higher frequency of G allele and GG genotype in Croatian COPD patients was observed. There was no evidence for the association of hsp70-hom (+ 2437T/C), TNF-α (+ 489G/A) SNPs and HMOX-1 (number of GT repeats) polymorphism with COPD. Allele and genotype frequencies for all of the tested polymorphisms show no association with disease severity (GOLD II-IV). 相似文献