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This study aimed to analyze surgical procedures for head and neck Ewing sarcoma (HNES) with regard to oncological, functional, and esthetic outcomes.A blinded multidisciplinary retrospective chart review of operated French HNES patients (Euro-EWING 99 trial, 1999–2014) was performed to assess patient/tumor characteristics, treatment details, and outcomes.Primary surgery without reconstruction was undertaken in 13 patients (emergency context/misdiagnosis). However, because of contaminated surgical margins, all patients had to undergo systematic postoperative radiotherapy. Twenty-six patients underwent multidisciplinary evaluation and were scheduled to undergo postchemotherapy surgery, with 19 patients scheduled for immediate reconstruction. All cases showed R0 margins after postchemotherapy surgery of the initial tumor bed by multidisciplinary surgical teams, while n = 3/4 of local relapses (very poor prognosis) had R1a margins after surgery of the residual tumor volume following chemotherapy. Only three surgical expertise centers operated on ≥ 4 patients over the 15-year period. Thirty patients developed long-term sequelae, with increased complications following radiotherapy.Referring patients to surgical expertise centers following a suspected diagnosis, with planned postchemotherapy surgery of the initial tumor bed at these centers, might limit the need for intralesional resections, allowing radical R0 resections and thus reducing long-term sequelae as well as the risk of secondary radio-induced malignancy by limiting the need for postoperative radiotherapy.  相似文献   
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《Radiography》2022,28(3):746-750
IntroductionIn response to advice from The National Institute for Health and Care Excellence (1) to reduce hospital visits during COVID-19, standard headrests were introduced for head and neck radiotherapy within Northern Centre for Cancer Care (NCCC). The standard headrest requires one mould room appointment compared to 3 appointments with customised headrests.MethodsTwo groups of 10 patients treated between December 2019 and June 2020 were retrospectively analysed by 1 observer. Groups were stratified according to age, sex and tumour site. One group had customised headrest and the other had standard headrest. Five hundred and forty seven cone beam computed tomography images were reviewed. A 6 Degree of Freedom match was performed then chin, shoulder and spine position were assessed using dosimetrist drawn structures. Structures out of the tolerance were recorded. A chi-squared test was used for statistical analysis.ResultsThe out of tolerance chin position count recorded was 21 for customised headrest and 36 for standard headrest, p-value 0.046. The shoulder position count was 13 for customised headrest and 77 for standard headrest p-value <0.001. The spine position count was 3 for CHR and 21 for standard headrest, p-value <0.001. This means the headrests compared are not equivalent in terms of set up reproducibility. Overall the standard headrest group had 10 set-up re-scans and no set up re-scans were recorded in the customised headrest group.ConclusionFewer hospital visits with SHR reduce patient exposure to COVID-19. However, CHR provided a more reliable level of immobilisation in this study.Implications for practiceThe radiotherapy service will be reviewed in line with these findings.  相似文献   
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Background: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, and the prognosis of HNSCC remains bleak. Numerous studies revealed that the tumor mutation burden (TMB) could predict the survival outcomes of a variety of tumors.Objectives: This study aimed to investigate the TMB and immune cell infiltration in these patients and construct an immune-related genes (IRGs) prognostic model.Methods: The expression data of 546 HNSCC patients were obtained from The Cancer Genome Atlas (TCGA) database. All patients were divided into high- and low- TMB groups, and the relationship between TMB and clinical relevance was further analyzed. The differentially expressed genes (DEGs) were identified using the R software package, limma. Functional enrichment analyses were conducted to identify the significantly enriched pathways between two groups. CIBERSORT algorithm was adopted to calculate the abundance of 22 leukocyte subtypes. The IRGs prognostic model was constructed via the multivariate Cox regression analysis.Results: Missense mutation and single nucleotide variants (SNV) were the most predominant mutation types in HNSCC. TP53, TTN, and FAT1 were the most frequently mutated genes. Patients with high TMB were observed with worse survival outcomes. The functional analysis of TMB associated DEGs showed that the identified DEGs mainly involved in spliceosome, RNA degradation, proteasome, and RNA polymerase pathways. We observed that macrophages, T cells CD8, and T cells CD4 memory were the most commonly infiltrated subtypes of immune cells in HNSCC. Finally, an IRGs prognostic model was constructed, and the AUC of the ROC curve was 0.635.Conclusions: Our results suggest that high TMB is associated with poor prognosis in HNSCC patients. The constructed model has potential prognostic value for the prognosis of these individuals, and it needs to be further validated in large-scale and prospective studies.  相似文献   
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《Clinical neurophysiology》2021,132(2):498-504
Changes in physiological functions after spaceflight and simulated spaceflight involve several mechanisms. Microgravity is one of them and it can be partially reproduced with models, such as head down bed rest (HDBR). Yet, only a few studies have investigated in detail the complexity of neurophysiological systems and their integration to maintain homeostasis. Central nervous system changes have been studied both in their structural and functional component with advanced techniques, such as functional magnetic resonance (fMRI), showing the main involvement of the cerebellum, cortical sensorimotor, and somatosensory areas, as well as vestibular-related pathways. Analysis of electroencephalography (EEG) led to contrasting results, mainly due to the different factors affecting brain activity. The study of corticospinal excitability may enable a deeper understanding of countermeasures' effect, since greater excitability has been shown being correlated with better preservation of functions. Less is known about somatosensory evoked potentials and peripheral nerve function, yet they may be involved in a homeostatic mechanism fundamental to thermoregulation. Extending the knowledge of such alterations during simulated microgravity may be useful not only for space exploration, but for its application in clinical conditions and for life on Earth, as well.  相似文献   
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目的评价急性心肌梗死(心肌梗死)患者抢救期间配合应用优化急诊护理干预对抢救效果的影响。方法选择本院收治的急性心肌梗死患者,总计80例。除抢救治疗外,给予患者随机分组进行护理干预,对照组40例急性心肌梗死患者采取常规急诊护理,试验组40例急性心肌梗死患者采取优化急诊护理干预。比较对照组与试验组急性心肌梗死患者组间分诊评估时间、急救总时间、住院时间、救治成功率、护理满意度。结果经优化急诊护理的试验组急性心肌梗死患者的分诊评估、急救以及住院时间均少于对照组,护理满意度高于对照组(P<0.05)。另外,组间救治成功率比较(P>0.05)。结论急性心肌梗死患者抢救中运用优化急诊护理可以缩短患者抢救时间、提高抢救成功率。  相似文献   
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目的 对比分析T1WI_Star_VIBE_FS序列在头颈部肿瘤患者MR定位中不同扫描方式对图像质量、信噪比、对比噪声比等参数的影响,确定优选扫描方式。方法 回顾性分析 78例头颈部MR定位患者,分别采用组织补偿法(A组 23例)、分段扫描拼接法(B组 18例)和二者结合法(C组 37例)进行增强扫描,对比上述3种扫描方式获取的图像质量、颈前部软组织信噪比(SNR)和对比噪声比(CNR)的差异。结果 C组扫描方式可获取较高的图像质量评分;3种扫描方式获取图像的SNR的平均值分别为 214.70±148.78、91.95±59.26、307.61±127.80;CNR的平均值分别为 208.74±148.27、85.79±59.50、301.58±127.48;C组在图像质量评分、SNR和CNR方面均明显优于A、B组(P<0.01)。结论 推荐使用组织补偿和分段拼接扫描相结合方式作为头颈部肿瘤放疗MR定位的优选扫描方式。  相似文献   
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