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61.
Objective:To evaluate the multiparametric MRI in predicting chemotherapy response in pathologically proven cases of osteosarcoma and Ewing’s sarcoma. Correlation between the tumor size changes and internal breakdown using RECIST 1.1, modified RECIST, quantitative apparent diffusion coefficient (ADC) and tumor volume as well as dynamic contrast-enhanced MRI (DCE-MRI).Methods:The study included 104 patients pathologically proved osteosarcoma (53) and Ewing`s sarcoma (51) underwent MRI examinations; before and after chemotherapy. All patients were assessed using the RECIST 1.1 criteria, m-RECIST, quantitative ADC, and tumor volume evaluation. 21 patients underwent DCE-MRI curve type with quantitative parameters. Correlation between the different evaluations was carried out. Results were correlated with the post-operative pathology in 42 patients who underwent surgery and for statistical evaluation, Those patients were classified into responders (≥90% necrosis) and non-responders (<90% necrosis).Results:The initial mean ADC of 104 patients of osteosarcoma and Ewing’s sarcoma (0.90 ± 0.29) and (0.71 ± 0.16) respectively, differed significantly from that after treatment (1.62 ± 0.46) and (1.6 ± 0.39) respectively with (p<0.001).ADC variations (ADC%) in the non-progressive group were higher than those of the progressive group (128.3 ± 63.49 vs 36.34 ± 78.7) % with (p<0.001).ADC values and ADC variations were inversely correlated with morphologic changes, regardless of the effectiveness of chemotherapy expressed as changes in tumor size based on (RECIST 1.1, RECIST, and 3D volume). Linear regression analysis revealed a Pearson correlation coefficient of r=-0.427, -0.498 and -0.408, respectively with (p<0.001).An increase in the ADC value was not always associated with a reduction in tumor volume. The disease control rate (defined as the percentage of CR+PR+SD patients) was 89.4% and 93.9% according to RECIST 1.1 and m-RECIST respectively.42 out of the 104 patients had postsurgical histological evaluation as regards the chemotherapeutic response divided into two groups. ADC values showed a statistically significant difference between Group A and Group B being more evident with minimum ADC% (p<0.001).Conclusion:Quantitative diffusion-weighted imaging with ADC mapping and ADC % after chemotherapy allows a detailed analysis of the treatment response in osteosarcoma and Ewing’s sarcoma. The therapeutic response can be underestimated using RECIST 1.1, so the modified RECIST should be also considered.Advances in knowledge:Quantitative ADC especially ADC% provided an accurate non-invasive tool in the assessment of post-therapeutic cases of osteosarcoma and Ewing''s sarcoma  相似文献   
62.

Background

Despite the evolution of surgical techniques and implants, high energy tibial plateau fractures remain a challenging problem. The goals of treatment are to obtain a well-aligned stable joint with a painless functional range of motion and prevention of posttraumatic arthritis. Indirect reduction techniques and other soft tissue preservation methods safeguard the vascularity and emphasize restoring both joint congruity and the mechanical axis of the limb. The aim of this study was to evaluate the clinical outcome of using Ilizarov external fixator in the treatment of Schatzker type V–VI tibial plateau fracture.

Methods

This study was done during the period 2009–2011 for the treatment of 30 patients with high energy tibial plateau fractures (Schatzker type V in 17 and type VI in 13 patients) by Ilizarov external fixator. The mean age was 36 years .There were 23 males. The right limb was affected in 17 patients. There were 10 open fractures and other associated injuries in 9 patients.

Results

The mean of follow up period was 18 months. All the fractures were united in an average time of 15 weeks. There were pin track infection in 20 patients and other few complications in 8 patients. According to knee society score, there was an excellent result in 16.7 %, good in 60 %, fair in 20 %, and poor in 3.3 %.

Conclusion

Ilizarov external fixation is a safe and effective treatment option for high energy tibial plateau fractures with good functional results.  相似文献   
63.

Background

The purpose of this study was to assess prospectively operative results and complications of treatment of cervical spinal canal stenosis (CCS) by anterior cervical discectomy and fusion (ACDF) using a newly introduced Alexandria Modular Cage-Plate Construct (AMCPC).

Methods

Fifteen patients (eight males, seven females) with symptomatic CCS were treated by ACDF, with a mean age of 51.2 years. Post-operative assessment depended upon clinical and radiological results.

Results

Total number of operated levels was 25 levels, with a mean 1.67 levels/patient. Mean operative time was 69.6 min/level and 116 min/patient. Average blood loss was 78 mL/level and 130 mL/patient. Mean hospital stay was 2.8 days. Post-operative dysphagia/dysphonia persisted in one patient for 1 year. One patient developed C5 radiculopathy with grade 2 deltoid weakness that recovered after 3 months. According to Odom’s criteria, results were excellent in 13 patients (86.67 %), good in 1 (6.67 %), and fair in 1 patient. In 13 patients (23 cage-plates, 92 %), the implant showed to be completely contained until the end of follow-up (24 months). One patient had a broken screw and one had screw backing-out, both did not necessitate revision. The achieved sagittal profile was maintained without sinking-in of any cage.

Conclusion

AMCPC can be used safely for a variety of disorders requiring instrumentation and fusion. It is advantageous to stand-alone cage and to rigid cage-plates when intraoperative flexibility is needed. It overcomes the disadvantages of stand-alone cage, sinking-in, cage dislodgement and post-operative rekyphosis. In addition, it obviates the need for wearing post-operative neck collar.  相似文献   
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66.
BACKGROUND Atrioventricular block requiring permanent pacemaker(PPM) implantation is an important complication of transcatheter aortic valve replacement(TAVR).Application of machine learning could potentially be used to predict preprocedural risk for PPM.AIM To apply machine learning to be used to predict pre-procedural risk for PPM.METHODS A retrospective study of 1200 patients who underwent TAVR(January 2014-December 2017) was performed. 964 patients without prior PPM were included for a 30-d ...  相似文献   
67.
Rosmarinus species are aromatic plants that mainly grow in the Mediterranean region. They are widely used in folk medicine, food, and flavor industries and represent a valuable source of biologically active compounds (e.g., terpenoids, flavonoids, and phenolic acids). The extraction of rosemary essential oil is being done using three main methods: carbon dioxide supercritical extraction, steam distillation, and hydrodistillation. Furthermore, interesting antioxidant, antibacterial, antifungal, antileishmanial, anthelmintic, anticancer, anti‐inflammatory, antidepressant, and antiamnesic effects have also been broadly recognized for rosemary plant extracts. Thus the present review summarized data on economically important Rosmarinus officinalis species, including isolation, extraction techniques, chemical composition, pharmaceutical, and food applications.  相似文献   
68.
We describe a rare case of coronary artery aneurysms due to Kawasaki disease in an elderly patient. Our case presents multiple giant coronary artery aneurysms affecting the left coronary system which is less common compared with right coronary aneurysms. Giant coronary artery aneurysms are uncommon; even more rare is their association with ischemic symptoms, and treatment can be challenging. We describe a case of symptomatic multiple coronary artery aneurysms with symptom relief after coronary artery bypass grafting in an elderly patient.  相似文献   
69.
BackgroundAlthough direct oral anticoagulants (DOACs) have been shown to be effective at reducing the risk of stroke in patients with atrial fibrillation/flutter (AF), they are sometimes underdosed off-label to mitigate their associated higher bleeding risk. We sought to evaluate frequency and clinical outcomes of inappropriate underdosing of DOACS in patients with AF.MethodsWe conducted a study of subjects with AF who had a clinical indication for stroke prophylaxis (with a congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65 to 47 years, sex category [CHA2DS2-VASc] of 2 or greater) and were prescribed 1 of the 4 clinically approved DOACs (apixaban, rivaroxaban, dabigatran, or edoxaban). We compared all-cause mortality, composite of stroke and systemic embolism, composite of myocardial infarction (MI), acute coronary syndromes (ACS), and coronary revascularization, and major bleeding between patients appropriately dosed and inappropriately underdosed.ResultsA total of 8125 patients met inclusion criteria, with a mean follow up of 2.2 ± 2 years. Of those, 1724 patients (21.2%) were inappropriately dosed. After adjusting for baseline variables, there was no difference in all-cause mortality, risk of stroke or systemic embolism, International Society on Thrombosis and Haemostasis (ISTH) major bleeding, or composite of myocardial infarction, acute coronary syndromes, or coronary revascularization between patients appropriately dosed and inappropriately underdosed. In subgroup analysis, only apixaban demonstrated an increased incidence all-cause mortality (hazard ratio [HR] 1.24, 95% confidence interval [CI] 1.03-1.49) with inappropriate underdosing. There was no difference in the remaining clinical outcomes noted on subgroup analysis.ConclusionUnderdosing of DOACs did not minimize risk of bleeding, systemic embolization or all-cause mortality in patients with AF. Inappropriate underdosing with apixaban in particular was associated with increased all-cause mortality.  相似文献   
70.
Recent studies have suggested a potential prognostic role of alterations of the fragile histidine triad (FHIT) gene in diffuse large B-cell lymphoma. To evaluate possible mechanisms of FHIT inactivation and to further clarify its potential prognostic relevance, we analyzed a set of 114 diffuse large B-cell lymphoma with clinical follow-up information. Tissue microarrays were analyzed by immunohistochemistry for protein expression, and corresponding DNA samples were analyzed for FHIT promotor hypermethlyation. Reduced or absent FHIT expression was found in 75 of 114 diffuse large B-cell lymphoma (66%), but was unrelated to clinical tumor stage or patient prognosis. FHIT promotor hypermethylation was observed in 29 of 93 (23%) interpretable diffuse large B-cell lymphoma. Hypermethylation was not significantly correlated to protein expression loss, which could be explained by competing mechanisms for FHIT inactivation in a substantial fraction of non FHIT hypermethylated diffuse large B-cell lymphoma. Hypermethylation was significantly associated with poor prognosis of diffuse large B-cell lymphoma patients and predominantly seen in nongerminal center diffuse large B-cell lymphoma (27%), but less frequent (13%) in germinal center diffuse large B-cell lymphoma. In summary, these data suggest that promotor hypermethylation is responsible for reduced FHIT expression in a substantial subset of diffuse large B-cell lymphoma, which is primarily composed of nongerminal center subtype with poor patient prognosis.  相似文献   
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