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51.
The scapula free flap is often the first choice for reconstruction of bony defects of the facial skeleton. However, the vascularised rib as part of a free rib osteomyocutaneous flap may be a suitable second choice. We have investigated the morphology and clinical dimensions of the 7th rib and the scapula, and the ability of the available bone to carry dental implants. The age and sex of the cadaver, and the donor side, were also recorded. The dimensions of the scapulas and 7th ribs (n = 130 of each) from 65 cadavers were measured at 4 different points using osteometric methods. Examination showed that bone from the scapula and 7th rib were sufficient for placement of implants. The 7th rib gave reliable measurements for both height and width, and a consistent relation between compact and cancellous bone. Although the scapula provided adequate compact and cancellous bone, there were variations depending on the segment of bone chosen. Bones from male cadavers were more suitable for implantation. In both the scapula and the 7th rib ageing had a significant adverse effect in only one dimension. Most points of measurement have satisfactory bony dimensions for insertion of dental implants.  相似文献   
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BackgroundGlioblastoma is the most common primary malignancy of the central nervous system with a dismal prognosis. Genomic signatures classify isocitrate dehydrogenase 1 (IDH)-wildtype glioblastoma into three subtypes: proneural, mesenchymal, and classical. Dasatinib, an inhibitor of proto-oncogene kinase Src (SRC), is one of many therapeutics which, despite promising preclinical results, have failed to improve overall survival in glioblastoma patients in clinical trials. We examined whether glioblastoma subtypes differ in their response to dasatinib and could hence be evaluated for patient enrichment strategies in clinical trials.MethodsWe carried out in silico analyses on glioblastoma gene expression (TCGA) and single-cell RNA-Seq data. In addition, in vitro experiments using glioblastoma stem-like cells (GSCs) derived from primary patient tumors were performed, with complementary gene expression profiling and immunohistochemistry analysis of tumor samples.ResultsPatients with the mesenchymal subtype of glioblastoma showed higher SRC pathway activation based on gene expression profiling. Accordingly, mesenchymal GSCs were more sensitive to SRC inhibition by dasatinib compared to proneural and classical GSCs. Notably, SRC phosphorylation status did not predict response to dasatinib treatment. Furthermore, serpin peptidase inhibitor clade H member 1 (SERPINH1), a collagen-related heat-shock protein associated with cancer progression, was shown to correlate with dasatinib response and with the mesenchymal subtype.ConclusionThis work highlights further molecular-based patient selection strategies in clinical trials and suggests the mesenchymal subtype as well as SERPINH1 to be associated with response to dasatinib. Our findings indicate that stratification based on gene expression subtyping should be considered in future dasatinib trials.  相似文献   
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Background: Wilson disease (WD) is an autosomal recessive inherited disorder of copper (Cu2+) metabolism, resulting in Cu2+ accumulation and liver and central nervous system toxicity. Oxidative stress may have a role in the pathogenesis of Wilson disease, but the roles of thiol/disulfide homeostasis and nitrosative stress have not been examined. The purpose of this study was to evaluate whether there is a modification in thiol/disulfide homeostasis and nitrosative stress in patients with Wilson disease.Methods: A total of 50 patients with Wilson disease (42 under drug treatment and 8 newly diagnosed patients with no drug treatment) and 50 healthy gender- and age-matched controls were enrolled for this study. Serum native thiol and total thiol levels were measured with a spectrophotometric method. The number of disulfide bonds and the related ratios were determined from these measurements. Serum nitric oxide (NO) and 3-nitrotyrosine (3-NT) levels were analyzed using chemiluminescence and ELISA assays, respectively.Results: The average native thiol levels of the patient group under drug treatment were found to be markedly higher than the levels of controls (P < .05). We detected no marked changes in total thiol and disulfide levels, and disulfide/total thiol, disulfide/native thiol, or native thiol/total thiol ratios between groups. We found significant elevations in NO levels in Wilson disease group before drug treatment, and the 3-NT levels in the Wilson disease groups prior to (P < .05) and under drug treatment (P < .01), when compared to controls.Conclusion: Our data are the first to show that nitrosative stress and thiol/disulfide homeostasis can contribute to the pathogenesis of Wilson disease.  相似文献   
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Atherosclerotic plaques tend to involve arterial localizations in which blood flow is not laminar due to arterial bends and bifurcations. A 49-year-old man was admitted to hospital with breathlessness and was subsequently diagnosed with left ventricular failure. Coronary angiography revealed three-vessel coronary artery disease and an anomalous extra left anterior descending artery taking off from the right sinus of Valsalva and spared from atherosclerosis. The absence of side branches and the relative lack of bends in arterial geometry were considered to be the cause of resistance to atherosclerosis. The present case identifies local flow conditions as an important factor determining the genesis of atherosclerosis in arterial segments.  相似文献   
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Severe pulmonary disease caused by the novel coronavirus [severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)], has devastated many countries around the world.It has overwhelmed the medical system.The priorities of many institutions have changed to manage critically ill corona virus infectious disease-2019(COVID-19) patients,which affected the working style of many departments.Hepatologists and transplant surgeons look after a very sensitive patient group.Patients with liver disease need special attention and continuous follow-up.Similarly,transplant candidates also need special care.Healthcare professionals in the field of hepatology face the overwhelming task of taking care of COVID-19 patients with hepatic complications,liver disease or transplant patients who are SARS-CoV-2 positive,and the patients on routine surveillance who do not have COVID-19.This review will evaluate COVID-19 from the perspective of its effect on the liver and its possible effects on patients with liver disease.Furthermore,the level of care for liver transplant recipients during the pandemic will be discussed.  相似文献   
56.
In recent years, implantology has made significant progress, as it has now become a safe and predictable practice. The development of new geometries, primary and secondary, of new surfaces and alloys, has made this possible. The purpose of this review is to analyze the different alloys present on the market, such as that in zirconia, and evaluate their clinical differences with those most commonly used, such as those in grade IV titanium. The review, conducted on major scientific databases such as Scopus, PubMed, Web of Science and MDPI yielded a startling number of 305 results. After the application of the filters and the evaluation of the results in the review, only 10 Randomized Clinical Trials (RCTs) were included. Multiple outcomes were considered, such as Marginal Bone Level (MBL), Bleeding on Probing (BoP), Survival Rate, Success Rate and parameters related to aesthetic and prosthetic factors. There are currently no statistically significant differences between the use of zirconia implants and titanium implants, neither for fixed prosthetic restorations nor for overdenture restorations. Only the cases reported complain about the rigidity and, therefore, the possibility of fracture of the zirconium. Certainly the continuous improvement in these materials will ensure that they could be used safely while maintaining their high aesthetic performance.  相似文献   
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AIM: To assess the bond strength of the new resin-based Epiphany-Resilon root canal filling system, and to compare this with bond strengths of different pairings of AH Plus, gutta-percha, Epiphany and Resilon. METHODOLOGY: A total of 65 extracted human single-rooted teeth were used. All teeth were instrumented using a set of ProTaper rotary instruments. Irrigation was performed with 15 mL of 1.25% NaOCl between each instrument and the smear layer was removed during and after instrumentation with 5 mL of 17% EDTA. The canal spaces were filled with different combinations of core and sealer using lateral condensation, as follows: group 1, AH Plus + gutta-percha; group 2, AH Plus + Resilon; group 3, Epiphany + Resilon; group 4, Epiphany + gutta-percha; group 5 (control), gutta-percha only. Cylinders of root dentine 1.13 (0.06)-mm long were prepared from the coronal sections of the 65 teeth. The test specimens were subjected to the push-out test method. After adhesion testing, the remaining sections were examined under a stereomicroscope at x 25 magnification to determine the nature of bond failure. The values of bond strength were analyzed by one-way analysis of variance (ANOVA) and the post hoc Tukey's test, with significance set at P < 0.05. RESULTS: The respective mean push-out test values for groups 1-5 were: 2.000 +/- 0.369, 1.380 +/- 0.154, 1.706 +/- 0.340, 2.857 +/- 0.523 and 0.078 +/- 0.027 MPa. Significant difference (P < 0.001) occurred between the groups. Multiple paired comparisons (Tukey's test) revealed that group 4 (Epiphany + gutta-percha) had significantly (P < 0.001) greater bonding strength than all the other groups; group 1 (AH Plus + gutta-percha) had significantly (P < 0.05) greater bonding strength than group 2 (AH Plus + Resilon); and group 5 (control) had significantly (P < 0.05) lower bonding strength than all the other groups. Inspection of the surfaces revealed the bond failure to be mainly adhesive to dentine for all groups. CONCLUSIONS: The Epiphany-Resilon combination (group 3) was not superior to that of the AH Plus-gutta percha combination (group 1).  相似文献   
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BACKGROUND: Varied vascular and biliary anatomies are common in the liver. Living donor hepatectomy requires precise recognition of the hilar anatomy. This study was undertaken to study donor vascular and biliary tract variations, surgical approaches and implications in living liver transplant patients. METHODS: Two hundred living donor liver transplantations were performed at our institution between 2004 and 2009. All donors were evaluated by volumetric computerized tomography (CT), CT angiography and magn...  相似文献   
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