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961.
We describe the case of a 23-year-old man with pulmonary histoplasmosis whose high-resolution CT scan demonstrated the reversed halo sign. We also extensively review the literature about this CT scan sign. The reversed halo sign has been described in a number of diseases, both infectious and noninfectious. However, to our knowledge, this is the first reported case of pulmonary histoplasmosis presenting with this radiologic finding. 相似文献
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Frank-Raue K Rybicki LA Erlic Z Schweizer H Winter A Milos I Toledo SP Toledo RA Tavares MR Alevizaki M Mian C Siggelkow H Hüfner M Wohllk N Opocher G Dvořáková S Bendlova B Czetwertynska M Skasko E Barontini M Sanso G Vorländer C Maia AL Patocs A Links TP de Groot JW Kerstens MN Valk GD Miehle K Musholt TJ Biarnes J Damjanovic S Muresan M Wüster C Fassnacht M Peczkowska M Fauth C Golcher H Walter MA Pichl J Raue F Eng C Neumann HP;International RET Exon Consortium 《Human mutation》2011,32(1):51-58
Multiple endocrine neoplasia type 2 is characterized by germline mutations in RET. For exon 10, comprehensive molecular and corresponding phenotypic data are scarce. The International RET Exon 10 Consortium, comprising 27 centers from 15 countries, analyzed patients with RET exon 10 mutations for clinical-risk profiles. Presentation, age-dependent penetrance, and stage at presentation of medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism were studied. A total of 340 subjects from 103 families, age 4-86, were registered. There were 21 distinct single nucleotide germline mutations located in codons 609 (45 subjects), 611 (50), 618 (94), and 620 (151). MTC was present in 263 registrants, pheochromocytoma in 54, and hyperparathyroidism in 8 subjects. Of the patients with MTC, 53% were detected when asymptomatic, and among those with pheochromocytoma, 54%. Penetrance for MTC was 4% by age 10, 25% by 25, and 80% by 50. Codon-associated penetrance by age 50 ranged from 60% (codon 611) to 86% (620). More advanced stage and increasing risk of metastases correlated with mutation in codon position (609→620) near the juxtamembrane domain. Our data provide rigorous bases for timing of premorbid diagnosis and personalized treatment/prophylactic procedure decisions depending on specific RET exon 10 codons affected. 相似文献
966.
Soares-Geraldo D Scaramucci T Steagall-Jr W Braga SR Sobral MA 《Brazilian Oral Research》2011,25(4):369-375
Composite resins might be susceptible to degradation and staining when in contact with some foods and drinks. This study evaluated color alteration and changes in microhardness of a microhybrid composite after immersion in different colored foods and determined whether there was a correlation between these two variables. Eighty composite disks were randomly divided into 8 experimental groups (n = 10): kept dry; deionized water; orange juice; passion fruit juice; grape juice; ketchup; mustard and soy sauce. The disks were individually immersed in their respective test substance at 37 oC, for a period of 28 days. Superficial analysis of the disk specimens was performed by taking microhardness measurements (Vickers, 50 g load for 45 seconds) and color alterations were determined with a spectrophotometer (CINTRA 10- using a CIEL*a*b* system, 400-700 nm wavelength, illuminant d65 and standard observer of 2o) at the following times: baseline (before immersion), 1, 7, 14, 21 and 28 days. Results were analyzed by ANOVA and Tukey's test (p < 0.05). Both variables were also submitted to Pearson's correlation test (p < 0.05). The passion fruit group underwent the greatest microhardness change, while the mustard group suffered the greatest color alteration. Significant positive correlation was found between the two variables for the groups deionized water, grape juice, soy sauce and ketchup. Not all color alteration could be associated with surface degradation. 相似文献
967.
One of the characteristics of diabetes mellitus is the exaggerated inflammatory response. The present report shows the reaction from the use of a rapid maxillary expander in a diabetic patient. A 9-year-old child presented an uncommon reaction to the treatment with a rapid maxillary expander, and on follow-up examination, it was discovered that the patient had diabetes mellitus. After controlling the disease, the proposed treatment was used without further incidents. The case calls attention to the presence of uncommon responses to treatment and the need for the orthodontist to suspect a patient's systemic compromise. 相似文献
968.
Introduction
Root canal contents are potent stimuli for proinflammatory cytokines involved in apical periodontitis. This study investigated target gram-negative bacterial species and endotoxins in primary endodontic infection with apical periodontitis, determined their antigenicity against macrophages through the levels of PGE2, and evaluated their relationship with clinical findings.Methods
Samples were taken from 21 root canals with primary infection and apical periodontitis by using paper points. Polymerase chain reaction (16S rDNA) was used for bacterial detection and limulus amebocyte lysate assay for endotoxin measurement. Levels of prostaglandin E2 (PGE2) were measured by enzyme-linked immunosorbent assay (Duoset Kit; R&D, Minneapolis, MN).Results
Prevotella nigrescens (13/21), Fusobacterium nucleatum (6/21), and Porphyromonas endodontalis (6/21) were the most frequently observed species. A positive association was found between F. nucleatum and P. endodontalis (P < .05). A correlation was found between the number of gram-negative bacterial species and the levels of endotoxins, as well as PGE2 (P < .05). Higher levels of endotoxin were detected in teeth with exudation, whereas elevated levels of PGE2 were found in teeth with tenderness to percussion and pain on palpation.Conclusions
Our findings imply an additive effect between the number of gram-negative bacterial species involved in endodontic infection regarding the induction of proinflammatory cytokine by macrophage cells. Moreover, teeth with clinical symptomatology were related to higher levels of endotoxins and PGE2 secretion. 相似文献969.
Mattos CT Vilani GN Sant'Anna EF Ruellas AC Maia LC 《International journal of oral and maxillofacial surgery》2011,(12):1347-1356
Oropharyngeal changes caused by orthognathic surgery have been a concern because the sleep quality of patients may be enhanced or worsened by these changes. The purpose of this meta-analysis was to identify, review and compare scientific literature about changes in airway in adult patients undergoing orthognathic surgery to correct anteroposterior osseous discrepancies. An electronic search of four databases was carried out up to July 2010, with supplemental hand searching of the references of the retrieved articles. Quality assessment of the included articles was carried out. Data were extracted and a meta-analysis was performed. Heterogeneity was assessed amongst the studies and results were presented in forest plots. 49 studies met the inclusion criteria. Only studies with moderate or high methodological soundness were included in the review. Moderate evidence was found to support a significant decrease in the oropharyngeal airway in mandibular setback surgery, a milder decrease in bimaxillary surgery to correct Class III and an increase in maxillomandibular advancement surgery. Evidence is lacking on airway volume changes after orthognathic surgery. 相似文献
970.