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1.
Graefe's Archive for Clinical and Experimental Ophthalmology - To develop a fully automated algorithm for accurate detection of fovea location in atrophic age-related macular degeneration...  相似文献   
2.
Oral squamous cell carcinomas (OSCCs) develop in genetically altered epithelium in the mucosal lining, also coined as fields, which are mostly not visible but occasionally present as white oral leukoplakia (OL) lesions. We developed a noninvasive genetic assay using next-generation sequencing (NGS) on brushed cells to detect the presence of genetically altered fields, including those that are not macroscopically visible. The assay demonstrated high accuracy in OL patients when brush samples were compared with biopsies as gold standard. In a cohort of Fanconi anemia patients, detection of mutations in prospectively collected oral brushes predicted oral cancer also when visible abnormalities were absent. We further provide insight in the molecular landscape of OL with frequent changes of TP53, FAT1 and NOTCH1. NGS analysis of noninvasively collected samples offers a highly accurate method to detect genetically altered fields in the oral cavity, and predicts development of OSCC in high-risk individuals. Noninvasive genetic screening can be employed to screen high-risk populations for cancer and precancer, map the extension of OL lesions beyond what is visible, map the oral cavity for precancerous changes even when visible abnormalities are absent, test accuracy of promising imaging modalities, monitor interventions and determine genetic progression as well as the natural history of the disease in the human patient.  相似文献   
3.
IntroductionAlthough hyperferritinemia may reflect the inflammatory status of patients with non-alcoholic fatty liver disease (NAFLD), approximately 33% of hyperferritinemia cases reflect real hepatic iron overload.AimTo evaluate a non-invasive method for assessing mild iron overload in patients with NAFLD using 3T magnetic resonance imaging (MRI) relaxometry, serum hepcidin, and the expression of ferritin subunits.MethodsThis cross-sectional study assessed patients with biopsy-proven NAFLD. MRI relaxometry was performed using a 3T scanner in all patients, and the results were compared with iron content determined by liver biopsy. Ferritin, hepcidin, and ferritin subunits were assessed and classified according to ferritin levels and to siderosis identified by liver biopsy.ResultsA total of 67 patients with NAFLD were included in the study. MRI revealed mild iron overload in all patients (sensitivity, 73.5%; specificity, 70%). For mild (grade 1) siderosis, the transverse relaxation rate (R2*) threshold was 58.9 s?1 and the mean value was 72.5 s?1 (SD, 33.9), while for grades 2/3 it was 88.2 s?1 (SD, 31.9) (p < 0.001). The hepcidin threshold for siderosis was > 30.2 ng/mL (sensitivity, 87%; specificity, 82%). Ferritin H and ferritin L subunits were expressed similarly in patients with NAFLD, regardless of siderosis. There were no significant differences in laboratory test results between the groups, including glucose parameters and liver function tests.ConclusionsMRI relaxometry and serum hepcidin accurately assessed mild iron overload in patients with dysmetabolic iron overload syndrome.  相似文献   
4.
The 2004 discovery of EGFR mutations, followed by ALK rearrangements, ushered in a targeted therapy era for advanced non-small cell lung cancer (NSCLC). Tyrosine kinase inhibitors targeting gene alterations have substantially improved survival and quality of life for patients with NSCLC. In the last decade, rearrangements of the ROS1 oncogene have been incorporated into healthcare practice that are applicable to another small subgroup of patients who benefit from similar targeted strategies. Recent genome studies of lung adenocarcinoma have identified other possible therapeutic targets, including RET, NTRK fusions, c-MET alterations, and activating mutations in KRAS, BRAF, and HER2, all with frequencies greater than 1%. Lung cancers harbouring these genome changes can potentially be treated with agents approved for other indications or under clinical development. This review updates the therapeutic arsenal that especially targets those genes.  相似文献   
5.
6.
Glioblastoma is an aggressive and fast-growing brain tumor with poor prognosis. Predicting the expected survival of patients with glioblastoma is a key task for efficient treatment and surgery planning. Survival predictions could be enhanced by means of a radiomic system. However, these systems demand high numbers of multicontrast images, the acquisitions of which are time consuming, giving rise to patient discomfort and low healthcare system efficiency. Synthetic MRI could favor deployment of radiomic systems in the clinic by allowing practitioners not only to reduce acquisition time, but also to retrospectively complete databases or to replace artifacted images. In this work we analyze the replacement of an actually acquired MR weighted image by a synthesized version to predict survival of glioblastoma patients with a radiomic system. Each synthesized version was realistically generated from two acquired images with a deep learning synthetic MRI approach based on a convolutional neural network. Specifically, two weighted images were considered for the replacement one at a time, a T2w and a FLAIR, which were synthesized from the pairs T1w and FLAIR, and T1w and T2w, respectively. Furthermore, a radiomic system for survival prediction, which can classify patients into two groups (survival >480 days and 480 days), was built. Results show that the radiomic system fed with the synthesized image achieves similar performance compared with using the acquired one, and better performance than a model that does not include this image. Hence, our results confirm that synthetic MRI does add to glioblastoma survival prediction within a radiomics-based approach.  相似文献   
7.
Inflammation - Sepsis affects 31.5 million people worldwide. It is characterized by an intense drop in blood pressure driving to cardiovascular morbidity and mortality. Modern supportive care has...  相似文献   
8.
Odontology - The purpose of this study was to investigate whether the root perforation repair with mineral aggregate-based cements affects the retention of customized fiberglass posts to bovine...  相似文献   
9.
BackgroundThe purpose of this study is to determine the comparative risk profile and clinical outcomes for patients undergoing reverse total shoulder arthroplasty (RTSA) for cuff tear arthropathy (CTA) without failed prior rotator cuff repair (RCR) compared with RTSA for CTA with prior RCR.MethodsFrom 2006 to 2014, all patients who underwent RTSA by two surgeons after failed RCR with minimum 2-year follow-up were identified. Patients who underwent RTSA with failed prior RCR were matched in a 1:1 ratio to patients undergoing primary RTSA, while controlling for demographic factors, prosthesis design, and surgeon. Postoperative active forward elevation and active external rotation were recorded. Outcome measures included American Shoulder and Elbow Surgeons score, Visual Analog Scale (VAS), and Simple Shoulder Test. Perioperative complications and rates of secondary reoperation were noted, and comparative multivariate analysis was performed.ResultsOf 262 patients, 192 (73.3%) were available at minimum 2-year follow-up. The prior RCR group had a significantly higher complication rate (17.4%, n = 15) than the primary RTSA group (3.8%, n = 4) (P = .001), although no significant difference in periprosthetic infection (P = .469) or secondary revision rate (P = .136) was observed. At mean 36.3 ± 26.1-month follow-up, the prior RCR group had statistically worse American Shoulder and Elbow Surgeons score (P < .001), VAS (P = .001), Simple Shoulder Test (P < .001), and active forward elevation (P = .006). Patients with multiple failed RCR attempts (n = 38) before RTSA demonstrated no significant differences versus isolated failed RCR (n = 48; P > .05).ConclusionThis study demonstrated that patients with RTSA after prior failed RCR have significantly worse patient-reported outcomes and greater rate of perioperative complications than patients undergoing primary RTSA for CTA.  相似文献   
10.
Graefe's Archive for Clinical and Experimental Ophthalmology - The purpose of this study was to measure the anti-angiogenic effect of N-desulfated Re–N-acetylated, a chemically modified...  相似文献   
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