164 resultados para diagnostic technique and procedure
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BACKGROUND: Ultrasonography (US), Computed Tomography (CT), and Magnetic Resonance imaging (MR) were compared for the staging of renal tumors. The differences between these imaging techniques were also studied for their ability to detect adenopathies, vascular invasion, distant intra-abdominal metastases, and particularly adjacent organ invasion. METHODS: Thirty-one patients with solid or complex renal masses were prospectively studied using US, CT, and MR. Differences between the results obtained were studied using the COCHRAN G test and the McNEMAR test. The sensitivity and specificity of each diagnostic technique were compared against a gold standard of the surgical and histopathological findings. RESULTS: The following sensitivities were obtained: For the detection of adenopathy, US 63.6%, CT and MR 90.9%. For vascular invasion, US 42.8%, CT and MR 85.7%. For the adjacent organ invasion, US 28.5%, CT 85.7%, and MR 71.4%. Some of the criteria that suggest invasion of adjacent structures include: the envelopment of the adjacent structures by the tumor, tumor extension into the adjacent structures with an irregular appearance, and alterations in shape, size, and density of adjacent structures. Loss of fat planes between the tumor and adjacent structures is not a sign of tumor invasion. CONCLUSIONS: Significant differences were found in the detection capacity of US in relation to CT and MR, which were similar. All three techniques were highly sensitive and specific only in the detection of distant abdominal metastases. In addition to the accuracy of these diagnostic modalities for the detection and staging of tumors, invasiveness, risks and cost should be considered in relation to relative costs and benefits.
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Three-phase three-wire power flow algorithms, as any tool for power systems analysis, require reliable impedances and models in order to obtain accurate results. Kron's reduction procedure, which embeds neutral wire influence into phase wires, has shown good results when three-phase three-wire power flow algorithms based on current summation method were used. However, Kron's reduction can harm reliabilities of some algorithms whose iterative processes need loss calculation (power summation method). In this work, three three-phase three-wire power flow algorithms based on power summation method, will be compared with a three-phase four-wire approach based on backward-forward technique and current summation. Two four-wire unbalanced medium-voltage distribution networks will be analyzed and results will be presented and discussed. © 2004 IEEE.
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Aim: To investigate the occurrence of chromosome 3, 7, 8, 9, and 17 aneuploidies, TP53 gene deletion and p53 protein expression in chronic gastritis, atrophic gastritis and gastric ulcer, and their association with H pylori infection. Methods: Gastric biopsies from normal mucosa (NM, n = 10), chronic gastritis (CG, n = 38), atrophic gastritis (CAG, n = 13) and gastric ulcer (GU, n = 21) were studied using fluorescence in situ hybridization (FISH) and immunohistochemical assay. A modified Giemsa staining technique and PCR were used to detect H pylori. An association of the gastric pathologies and aneuploidies with H pylori infection was assessed. Results: Aneuploidies were increasingly found from CG (21%) to CAG (31%) and to GU (62%), involving mainly monosomy and trisomy 7, trisomies 7 and 8, and trisomies 7, 8 and 17, respectively. A significant association was found between H pylori infection and aneuploidies in CAG (P = 0.0143) and GU (P = 0.0498). No TP53 deletion was found in these gastric lesions, but p53-positive immunoreactivity was detected in 45% (5/11) and 12% (2/17) of CG and GU cases, respectively. However, there was no significant association between p53 expression and H pylori infection. Conclusion: The occurrence of aneuploidies in benign lesions evidences chromosomal instability in early stages of gastric carcinogenesis associated with H pylori infection, which may confer proliferative advantage. The increase of p53 protein expression in CG and GU may be due to overproduction of the wild-type protein related to an inflammatory response in mucosa. © 2006 The WJG Press. All rights reserved.
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Objective: To evaluate the marginal microleakage in enamel and dentin/cementum walls in preparations with a high C-factor, using 3 resin composite insertion techniques. The null hypothesis was that there is no difference among the 3 resin composite insertion techniques. Method and Materials: Standardized Class 5 cavities were prepared in the lingual and buccal aspects of 30 caries-free, extracted third molars. The prepared teeth were randomly assigned to 3 groups: (1) oblique incremental placement technique, (2) horizontal incremental placement technique, and (3) bulk insertion (single increment). The preparations were restored with a 1-bottle adhesive (Single Bond, 3M ESPE) and microhybrid resin composite (Z100, 3M ESPE). Specimens were isolated with nail varnish except for a 2-mm-wide rim around the restoration and thermocycled (1,000 thermal cycles, 5°C/55°C; 30-second dwell time). The specimens were immersed in an aqueous solution of 50 wt% silver nitrate for 24 hours, followed by 8 hours in a photo-developing solution and evaluated for microleakage using an ordinal scale of 0 to 4. The microleakage scores obtained from occlusal and gingival walls were analyzed with Wilcoxon and Kruskal-Wallis nonparametric tests. Results: The null hypothesis was accepted. The horizontal incremental placement technique, the oblique incremental technique, and bulk insertion resulted in statistically similar enamel and dentin microleakage scores. Conclusion: Neither the incremental techniques nor the bulk placement technique were capable of eliminating the marginal microleakage in preparations with a high C-factor.
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To produce an epidemiological map of neosporosis in Brazil and identify the types of transmission of this disease, the present study evaluated the occurrence of Neospora caninum in Nelore cattle (Bos indicus) in Presidente Prudent, west region of Sao Paulo state; its vertical transmission; and the early stage in which fetuses are infected. To achieve this, serum samples from 518 slaughtered pregnant heifers and their fetuses were tested by ELISA technique and fetal brain tissues subjected to PCR. One hundred and three heifers (19.88%) had antibodies to N. caninum, as well as 38 (36.8%) of fetuses from 4 months of gestation. The conventional PCR failed to detect N. caninum DNA. These findings show that neosporosis occurs in the area studied and that it may be transmitted the transplacental route, althought N. caninum had not detected in brain tissue from non-aborted fetuses. The use of nested PCR it would be applied to increase the sensitivy of test.
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Tinplate is one of the most widely used food canning materials, however, there are significant problems related to the use of tinplate cans, such as alterations in sensory features affecting food quality and corrosion phenomena of the canning material. To avoid corrosion problems different methods have been used for the passivation of tinplate such protective lacquers or different kinds of corrosion inhibitors (chromate and dichromate). However, chromates and dichromates are extremely harmful to the environment and can cause carcinogenic tumors to humans. An option, protective coatings obtained by the sol-gel process, act as a physical barrier, which isolates the surface of metal protecting from the corrosive agents. The aim of this work is to study the influence of addition of cerium (IV) ions in the inorganic and organic part of sol-gel processing in the formation of hybrid coatings based on siloxane-PMMA on tin plate. The coatings were obtained by dip-coating technique and evaluated by open circuit and impedance measurements, linear polarization and polarization curves obtained in 3.5% NaCl solution. The results have clearly shown the improvement on the protective properties of the Ce 4+ modified film when added into the organic phase, which can be due to the formation of a more uniform and densely reticulated siloxane-PMMA film. © 2009 by NACE International.
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This study compared the sampling efficacy cia cytobrush and metal spatula for exfoliative cytology of the oral mucosa. Thirty students with no detectable oral alterations upon clinical examination were submitted to exfoliative cytology of the lateral border of the tongue, using a metal spatula on the left side and a cytobrush on the right side. The smears were stained using the Papanicoiaou technique and evaluated for cellularity, cell type, cell distribution, homogeneity, and cellular distortion, as well as the presence ol mucus, inflammatory infiltrate, and hemorrhage. A statistical test (Z-test) with a 95% confdence interval (Cl) showed a significant difference between the metal spatula and cytobrush in terms of cellularity (p = 0.02) and homogeneity (p = 0.01). No difference between the two methods was observed regarding cell type (p = 0.4, Z-test) or cell distribution for the 95% confidence interval (p = 0.2, Fisher's test). Cell distortion and the presence of mucus were observed in five cases that used the metal spatula and in two cases that used the cytobrush. No hemorrhage or inflammatory infItrate was detected in any of the slides. Based on the results of this study, the cytobrush produced qualitatively better smears in terms of cellularity and homogeneity compared to the metal spatula.
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This paper discusses the design and performance of the time measurement technique and of the synchronization systems of the CMS hadron calorimeter. Time measurement performance results are presented from test beam data taken in the years 2004 and 2006. For hadronic showers of energy greater than 100 GeV, the timing resolution is measured to be about 1.2 ns. Time synchronization and out-of-time background rejection results are presented from the Cosmic Run At Four Tesla and LHC beam runs taken in the Autumn of 2008. The inter-channel synchronization is measured to be within 2 ns. © 2010 IOP Publishing Ltd and SISSA.
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Background: Previous studies have pointed out that the mere elevation of the maxillary sinus membrane promotes bone formation without the use of augmentation materials. Purpose: This experimental study aimed at evaluating if the two-stage procedure for sinus floor augmentation could benefit from the use of a space-making device in order to increase the bone volume to enable later implant installation with good primary stability. Materials and Methods: Six male tufted capuchin primates (Cebus apella) were subjected to extraction of the three premolars and the first molar on both sides of the maxilla to create an edentulous area. The sinuses were opened using the lateral bone-wall window technique, and the membrane was elevated. One resorbable space-making device was inserted in each maxillary sinus, and the bone window was returned in place. The animals were euthanatized after 6 months, and biopsy blocks containing the whole maxillary sinus and surrounding soft tissues were prepared for ground sections. Results: The histological examination of the specimens showed bone formation in contact with both the schneiderian membrane and the device in most cases even when the device was displaced. The process of bone formation indicates that this technique is potentially useful for two-stage sinus floor augmentation. The lack of stabilization of the device within the sinus demands further improvement of space-makers for predictable bone augmentation. Conclusions: It is concluded that (1) the device used in this study did not trigger any important inflammatory reaction; (2) when the sinus membrane was elevated, bone formation was a constant finding; and (3) an ideal space-making device should be stable and elevate the membrane to ensure a maintained connection between the membrane and the secluded space. © 2009 Wiley Periodicals, Inc.
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Introduction: Intradural lumbar disc herniations are uncommon presentations of a relatively frequent pathology, representing less than 1% of all lumbar disc hernias. They show specific features concerning their clinical diagnosis, with a higher incidence of cauda equina syndrome, and their surgical treatment requires a transdural approach. Methods: In this article, we describe five cases of this pathology and review the literature as well as some considerations about the difficulties in the preoperative diagnostic issues and the surgical technique. Conclusion: We concluded that for intradural disc herniations the diagnosis is mainly intraoperative, and the surgical technique has some special aspects. © 2012 Springer-Verlag Berlin Heidelberg.
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Objective. The anti-inflammatory proteins annexin-A1 and galectin-1 have been associated with tumor progression. This scenario prompted us to investigate the relationship between the gene and protein expression of annexin-A1 (ANXA1/AnxA1) and galectin-1 (LGALS1/Gal-1) in an inflammatory gastric lesion as chronic gastritis (CG) and gastric adenocarcinoma (GA) and its association with H. pylori infection. Methods. We analyzed 40 samples of CG, 20 of GA, and 10 of normal mucosa (C) by the quantitative real-time PCR (qPCR) technique and the immunohistochemistry assay. Results. High ANXA1 mRNA expression levels were observed in 90% (36/40) of CG cases (mean relative quantification RQ = 4.26 ± 2.03) and in 80% (16/20) of GA cases (mean RQ = 4.38 ± 4.77). However, LGALS1 mRNA levels were high (mean RQ = 2.44 ± 3.26) in 60% (12/20) of the GA cases, while low expression was found in CG (mean RQ = 0.43 ± 3.13; P < 0.01). Normal mucosa showed modest immunoreactivity in stroma but not in epithelium, while stroma and epithelium displayed an intense immunostaining in CG and GA for both proteins. Conclusion. These results have provided evidence that galectin-1 and mainly annexin-A1 are overexpressed in both gastritis and gastric cancer, suggesting a strong association of these proteins with chronic gastric inflammation and carcinogenesis. © 2013 Yvana Cristina Jorge et al.
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In this paper, we report on a field experiment being carried out in a Typic Eutrorthox. The experiment was initiated in the 1997-98 agricultural season as a randomized block design with four treatments (0, 5, 10, and 20 t ha -1) of sewage sludge and five replicates. Compound soil samples were obtained from 20 subsamples collected at depths of 0-0.1 and 0.1-0.2 m. Cu, Fe, Mn, and Zn concentrations were extracted with DTPA pH 7.3; 0.1 mol L -1 HCl, Mehlich-I, Mehlich-III, and 0.01 mol L-1 CaCl 2. Metal concentrations were determined via atomic absorption spectrometry. Diagnostic leaves and the whole above-ground portion of plants were collected to determine Cu, Fe, Mn, and Zn concentrations extracted by nitric-perchloric digestion and later determined via atomic absorption spectrometry. Sewage sludge application caused increases in the concentrations of soil Cu, Fe, and Mn in samples taken from the 0-0.1 m depth evaluated by the extractants Mehlich-I, Mehlich-III, 0.01 mol L-1 HCl and DTPA pH 7.3. None of the extractants provided efficient estimates of changes in Mn concentrations. The acid extractants extracted more Cu, Fe, Mn, and Zn than the saline and chelating solutions. The highest concentrations of Cu, Fe, and Zn were obtained with Mehlich-III, while the highest concentrations of Mn were obtained with HCl. We did not observe a correlation between the extractants and the concentrations of elements in the diagnostic leaves nor in the tissues of the whole maize plant (Zea mays L.). © 2013 Springer Science+Business Media Dordrecht.
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The expression of prognostic markers in cancer has become important in diagnostic routine and research. A high mitotic rate compromises the individual cell access to oxygen and nutrients, due to reduced blood supply. Cells undertake adaptive measures such as vascular endothelial growth factor (VEGF), expressed under the control of hypoxia-inducible factor-1α (HIF-1α). CD34 is an endothelial marker which can show the presence and distribution of blood vessels. This study evaluated the presence and relative expression of VEGF, HIF-1α and CD34 using immunohistochemistry of 60 breast tumors and double staining, correlating the findings with clinical and pathological variables. High VEGF expression was correlated with low cell proliferation, lymph node-negative, smaller tumor size and patients not receiving hormone therapy. High HIF-1α expression predominated in younger (<50-year) patients, subjected to neo-adjuvant therapy and in p53-negative tumors. Absence of metastasis, radiotherapy or hormone treatment, and estrogen receptor (ER)-positive tumors showed high CD34 immunoreactivity. We suggest that the angiogenic factors VEGF, HIF-1α and CD34 are important in breast cancer progression and their abundance in breast tumors has prognostic and predictive value. Crown Copyright © 2013.
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Oxacillin is an alternative for the treatment of Staphylococcus spp. infections; however, resistance to this drug has become a major problem over recent decades. The main objective of this study was to epidemiologically characterize coagulase-negative staphylococci (CoNS) strains recovered from blood of patients hospitalized in a Brazilian teaching hospital. Oxacillin resistance was analyzed in 160 strains isolated from blood culture samples by phenotypic methods, detection of the mecA gene, and determination of intermediate sensitivity to vancomycin on brain heart infusion agar supplemented with 4 and 6 μg/mL vancomycin. In addition, characterization of the epidemiological profile by staphylococcal cassette chromosome mec (SCC. mec) typing and clonal analysis by pulsed-field gel electrophoresis (PFGE) were performed. The mecA gene was detected in 72.5% of the isolates. Methicillin-resistant CoNS isolates exhibited the highest minimum inhibitory concentrations and multiresistance when compared to methicillin-susceptible CoNS strains. Typing classified 32.8% of the isolates as SCC. mec I and 50% as SCC. mec III. PFGE typing of the SCC. mec III Staphylococcus epidermidis isolates identified 6 clones disseminated in different wards that persisted from 2002 to 2009. The high oxacillin resistance rates found in this study and clonal dissemination in different wards highlight the importance of good practices in nosocomial infection control and of the rational use of antibiotic therapy in order to prevent the dissemination of these clones. © 2013 Elsevier Inc.
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Pós-graduação em Bases Gerais da Cirurgia - FMB