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Parasitology Research - Trypanosoma lewisi (Kinetoplastea: Trypanosomatida: Trypanosomatidae) with a cosmopolitan distribution is the type species of the subgenus Herpetosoma, which includes ca. 50...  相似文献   
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Immunohistochemical investigation in odontogenic myxoma   总被引:1,自引:0,他引:1  
Three odontogenic myxomas are described immunohistochemically by a panel of poly- and monoclonal antibodies to characterize this tumor type. Three types of odontogenic myxoma cells were discriminated: spindle cells, stellate cells and hyaline cells. Neoplastic cells of myxomas were positively stained for transferrin, ferritin, alpha-1-antichymotrypsin (alpha 1-ACT), alpha-1-antitrypsin (alpha 1-AT), S-100 protein and vimentin; however, neuron specific enolase (NSE), S-100 alpha subunit, S-100 beta subunit, Factor VIII-related antigen (FVIII-AG) and cytokeratin (CK1) were negative. Spindle cells were positive for transferrin, ferritin, alpha 1-ACT, alpha 1-AT, S-100 protein and vimentin. Stellate cells were strongly positive for transferrin, alpha 1-AT, S-100 protein and vimentin. Hyaline cells reacted with alpha 1-ACT and alpha 1-AT. Myxomatous matrix showed negative reaction for all the antibodies used. These results have confirmed that odontogenic myxoma is a tumor of a dual fibroblastic-histiocytic origin.  相似文献   
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OBJECTIVES: The objective of this study was to examine the possible correlation between the strength of glass ionomers and their adhesive strength to metals. METHODS: Three different brands of glass ionomers mixed at four different P/L ratios were evaluated. The compressive and diametral tensile strengths of the cements were determined. The shear bond strengths were determined between four different types of dental casting alloys and the cement made with the different P/L ratios. RESULTS: Significant (p < 0.05) increases in the bond strength to any of the metal surfaces were found in the cement specimens mixed at the highest P/L ratio compared to those mixed at the lowest P/L ratio. For two glass ionomers (FI and DNT), the specimens prepared at the highest P/L ratio showed significantly greater diametral tensile strength than those prepared at the lowest P/L ratio (p < 0.05). SIGNIFICANCE: The present study showed a significant correlation between diametral tensile strengths and bond strengths. It is suggested that the use of glass ionomers with high mechanical strength is an important factor of enhancing the adhesion to metal surfaces.  相似文献   
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This study evaluated the mechanical performance of teardrop-shaped loops and teardrop-shaped loops with helix used in orthodontic space closure. Sixty retraction loops made with 0.019" x 0.025" stainless steel (SS) and beta-titanium (BT) wires were used. They were attached to a testing machine to measure the magnitudes of the sagittal force and the load-deflection ratio necessary for 1 mm, 2 mm and 3 mm activation. The results demonstrated that the BT alloy presented significantly smaller mean values (p < 0.01) of sagittal force and load-deflection than the SS alloy. The loop with the highest mean value of sagittal force and load-deflection was the teardrop-shaped loop (p < 0.01). Differences were observed in the mean values of sagittal force and load-deflection among activations, and the highest mean value was found in the activation of 3 mm, while the smallest mean value was evident in the activation of 1 mm (p < 0.01). It could be concluded that the metallic alloy used and the presence of a helix in configuration of the loops may have a strong influence on the sagittal force produced and on the load-deflection ratio; the teardrop-shaped loops and teardrop-shaped loops with helix in BT presented the release of lighter forces; the teardrop-shaped loop in SS generated a high load-deflection ratio, providing high magnitudes of horizontal force during its deactivation.  相似文献   
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PURPOSE: The purpose of this study was to determine whether a resorbable poly-l-lactide (PLLA) miniplate system could be used to treat mandibular condylar process fracture. PATIENTS AND METHODS: Fourteen patients (12 males, 2 females, aged 23.1 +/- 5.7 years) who had mandibular condylar process fractures treated with PLLA implants were recalled for follow-up clinical and radiologic examinations at 3 years. RESULTS: Mouth opening recovered to more than 35 mm and occlusion was stable in all patients. There was no facial asymmetry 3 months postoperatively. Two patients had mild chronic postoperative tenderness at the implantation site; however, there was no wound infection. All fractured mandibular condyles showed anatomic good reduction and long-term stability with the use of resorbable miniplates and screws. Bone healing was satisfactory in all patients, and there was no evidence of abnormal resorption of the condylar process. The screw holes remained evident after 3 years. Screw holes in 2 patients showed enlargement on radiographic examination. CONCLUSION: The PLLA miniplate system provides reliable stability when used for the fixation of mandibular condylar process fractures.  相似文献   
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