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971.
A free‐floating thrombus in the left atrium is very rare in mitral stenosis. Such a thrombus can lead to sudden circulatory arrest and syncope or can cause severe cerebral or peripheral thromboembolic events. Clinical diagnosis is difficult, but left atrial thrombus should be suspected if patients with mitral stenosis and atrial fibrillation have intermittent or changing murmurs, emboli, or syncope. We describe the case of a patient with mild mitral stenosis under warfarin therapy, and a left atrial pedunculated thrombus discovered during the investigation for syncope attacks. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42:252–255, 2014  相似文献   
972.

Introduction  

Early gastric cancer (EGC) has an excellent prognosis, but tumors recur in some patients even after apparently successful treatment. Among recurrent sites, the liver is one of the most common. In this study, we investigated clinicopathological features and factors predicting the development of liver metastasis from EGC.  相似文献   
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In this article, the authors are presenting their experience and the results with the surgical treatment of intraorbital intraconal tumors based on a review of 33 constitutive cases. Our data were evaluated in comparison to other major series, and possible factors that might influence surgical outcome and survival are discussed. Thirty-three patients diagnosed with intraorbital intraconal tumors between 1998 and 2009 were treated by transcranial approach. Of these patients, there were 14 males (42.4?%) and 19 females (57.8?%). The age ranged between 2 and 70?years (mean?=?36?±?16.6?years). The follow-up period ranged between 2 and 13?years (mean?=?7.3?±?3.2?years). The most common presenting symptoms were exophthalmus and decreased visual acuity, which was seen in 21 (63.6?%) and 19 patients (57.6?%), respectively. Total resection was achieved in 23 patients (69.7?%) while subtotal resection was done in ten patients (30.3?%). Cavernoma and optic nerve sheath meningioma were the most common histologic variants, which were found in 11 (33.3?%) and 10 (30.3?%) patients, respectively. In the long-term follow-up, 54.5?% of the patients showed total ophthalmologic improvement, 9.1?% showed partial improvement, 21.2?% demonstrated unchanged ophthalmologic status, and 15.2?% showed worse ophthalmologic outcome. Transcranial approach for the treatment of intraorbital intraconal tumors is an effective approach for the management of these pathologies. The effectiveness is clearly demonstrated by the clinical results and outcomes of these patients' groups.  相似文献   
977.

PURPOSE

The aim of the study was to evaluate the effect of annealing on the nanostructure and hardness of Co-Cr metal ceramic samples that were fabricated with a direct metal laser sintering (DMLS) technique.

MATERIALS AND METHODS

Five groups of Co-Cr dental alloy samples were manufactured in a rectangular form measuring 4 × 2 × 2 mm. Samples fabricated by a conventional casting technique (Group I) and prefabricated milling blanks (Group II) were examined as conventional technique groups. The DMLS samples were randomly divided into three groups as not annealed (Group III), annealed in argon atmosphere (Group IV), or annealed in oxygen atmosphere (Group V). The nanostructure was examined with the small-angle X-ray scattering method. The Rockwell hardness test was used to measure the hardness changes in each group, and the means and standard deviations were statistically analyzed by one-way ANOVA for comparison of continuous variables and Tukey''s HSD test was used for post hoc analysis. P values of <.05 were accepted as statistically significant.

RESULTS

The general nanostructures of the samples were composed of small spherical entities stacked atop one another in dendritic form. All groups also displayed different hardness values depending on the manufacturing technique. The annealing procedure and environment directly affected both the nanostructure and hardness of the Co-Cr alloy. Group III exhibited a non-homogeneous structure and increased hardness (48.16 ± 3.02 HRC) because the annealing process was incomplete and the inner stress was not relieved. Annealing in argon atmosphere of Group IV not only relieved the inner stresses but also decreased the hardness (27.40 ± 3.98 HRC). The results of fitting function presented that Group IV was the most homogeneous product as the minimum bilayer thickness was measured (7.11 Å).

CONCLUSION

After the manufacturing with DMLS technique, annealing in argon atmosphere is an essential process for Co-Cr metal ceramic substructures. The dentists should be familiar with the materials that are used in clinic for prosthodontics treatments.  相似文献   
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979.
Background: The aim of this study is to examine, for the first time, the role of systemic and local atorvastatin application on periodontium using histomorphometric and immunohistochemical analysis during and after experimental periodontitis induction with or without the presence of microbial dental biofilm. Methods: One hundred ten male Wistar rats were used. Silk ligatures were placed around the cervical area of the mandibular first molars; rats in the healthy control group received no ligatures (n = 10). In experimental periodontitis groups (n = 90), systemic and local atorvastatin and saline were administered in three different periods; the control periodontitis group (n = 10) received no treatment. Histomorphometric analysis, which included alveolar bone area, alveolar bone level, and attachment loss, and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP)‐9, were performed after the rats were sacrificed at the end of the experimental procedure. Results: There was a greater increase in alveolar bone area and VEGF immunoreactivity, as well as a greater decrease in alveolar bone and attachment loss and MMP‐9 immunoreactivity, with systemic and local atorvastatin application during and after induction of experimental periodontitis. Local atorvastatin application showed better results on periodontium with regard to alveolar bone findings. Conclusions: Systemic and local atorvastatin application showed beneficial effects on periodontium during and after induction of experimental periodontitis. Within the limits of this study, it can be concluded that atorvastatin, which is used for hypercholesterolemia treatment, can also be used as a protective and therapeutic agent for periodontal disease.  相似文献   
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