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PurposeTo evaluate tumor and ablation zone morphology and densitometry related to tumor recurrence in participants with Stage IA non–small cell lung cancer undergoing radiofrequency ablation in a prospective, multicenter trial.Materials and MethodsForty-five participants (median 76 years old; 25 women; 20 men) from 16 sites were followed for 2 years (December 2006 to November 2010) with computed tomography (CT) densitometry. Imaging findings before and after ablation were recorded, including maximum CT attenuation (in Hounsfield units) at precontrast and 45-, 90-, 180-, and 300-s postcontrast.ResultsEvery 1-cm increase in the largest axial diameter of the ablation zone at 3-months’ follow-up compared to the index tumor reduced the odds of 2-year recurrence by 52% (P = .02). A 1-cm difference performed the best (sensitivity, 0.56; specificity, 0.93; positive likelihood ratio of 8). CT densitometry precontrast and at 45 seconds showed significantly different enhancement patterns in a comparison among pretreated lung cancer (delta = +61.2 HU), tumor recurrence (delta = +57 HU), and treated tumor/ablation zone (delta [change in attenuation] = +16.9 HU), (P < .0001). Densitometry from 45 to 300 s was also different among pretreated tumor (delta = −6.8 HU), recurrence (delta = −11.2 HU), and treated tumor (delta = +12.1 HU; P = .01). Untreated and residual tumor demonstrated washout, whereas treated tumor demonstrated increased attenuation.ConclusionsAn ablation zone ≥1 cm larger than the initial tumor, based on 3-month follow-up imaging, is recommended to decrease odds of recurrence. CT densitometry can delineate tumor versus treatment zones.  相似文献   
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Introduction

Compression fractures of the cuboid bone in children and adolescents are rare. Fracture morphology, associated lesions, treatment options and long-term outcomes of this very rare injury are published in a few case reports. This study with review of the literature aims to support the understanding of fracture pattern and optimize pathways of decision making.

Material and Methods

A retrospective two-center study was performed in a patient cohort treated between 2001 and 2016. All patients aged less than 18 years who sustained a cuboid fracture were included. Age, gender, mechanism of injury, fracture morphology, amount of displacement, associated injuries, and therapy were analyzed. In the follow-up (FU), the AOFAS Midfoot Scale was investigated.

Results

Fractures of the cuboid bone were diagnosed in 7 boys and 9 girls. The mean age of the patients was 10 years (range: 2.2–16.1 years). According to the classification of Fenton we detected 11 (69%) type 2, 2 (12%) type 3 and 3 (19%) type 5b fractures. Other fracture types according to Fenton were not observed. All children under 10 years sustained a type 2 fracture. Open reduction and internal fixation was performed in 5 (31%) patients. Bone grafting was not necessary. FU was performed in 14/16 patients on average after 9 years (mean; range: 1.4–16.2 years). The mean AOFAS Midfoot Scale at FU for extra-articular type 2 fractures was 100 points, whereas in intra-articular fractures (Type 3) and fractures associated with mid-tarsal disruption (type 5b) worse results were found (95 and 66 points, accordingly).

Conclusion

This rare injury shows inhomogenous morphologies and offers different treatment approaches. Extra-articular Fenton type 2 lesions are the most common type of cuboid fracture in children (69%). A potential loss of length of the lateral column must be considered. In contrast to adults, type 1, 4, and 5a fractures were not found in our cohort of children and adolescents. Lower scores of the AOFAS Midfoot Scale were found with either intra-articular involvement or associated midfoot lesions.  相似文献   
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Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
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高亮亮 《河北医学》2016,(10):1602-1604
目的::研究股骨近端空心锁定板内固定治疗股骨颈骨折的临床效果。方法:对2008年2月至2010年4月我院入院治疗的108例股骨颈骨折患者进行了研究,随机分为两组,对照组给与空心钉进行治疗,观察组采用股骨近端空心锁定板内固定治疗,比较两组治疗方案的手术时间、出血量、住院时间以及下床时间,比较两组治疗方案的手术并发症发生率,并比较两组患者三年期临床疗效。结果:观察组患者手术出血量明显少于对照组,手术时间、住院时间以及下床时间明显短于对照组,两组比较差异明显,有统计学意义( P<0.05);两组患者手术并发症均以疼痛、骨不连以及感染为主,其中观察组上述并发症的发生率为13.0%,明显低于对照组33.3%,两组比较差异有统计学意义( P<0.05);观察组患者三年临床总有效率为79.6%,对照组患者三年期临床总有效率为51.9%,两组比较差异明显,有统计学意义( P<0.05)。结论:股骨近端空心锁定板内固定治疗股骨颈骨折临床效果显著,可以明显缩短手术时间以及住院时间,降低手术并发症,并且三年临床总有效率更高,值得临床推广应用。  相似文献   
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Epigenetics refers broadly to processes that influence medium to long‐term gene expression by changing the readability and accessibility of the genetic code. The Neurobiology Commission of the International League Against Epilepsy (ILAE) recently convened a Task Force to explore and disseminate advances in epigenetics to better understand their role and intersection with genetics and the neurobiology of epilepsies and their co‐morbidities, and to accelerate translation of these findings into the development of better therapies. Here, we provide a topic primer on epigenetics, explaining the key processes and findings to date in experimental and human epilepsy. We review the growing list of genes with epigenetic functions that have been linked with epilepsy in humans. We consider potential practical applications, including using epigenetic signals as biomarkers for tissue‐ and biofluid‐based diagnostics and the prospects for developing epigenetic‐based treatments for epilepsy. We include a glossary of terms, FAQs and other supports to facilitate a broad understanding of the topic for the non‐expert. Last, we review the limitations, research gaps and the next challenges. In summary, epigenetic processes represent important mechanisms controlling the activity of genes, providing opportunities for insight into disease mechanisms, biomarkers and novel therapies for epilepsy.  相似文献   
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IntroductionAcetabulum fractures, though relatively uncommon, are associated with significant morbidity and mortality. These involve high energy trauma and due to their complex nature, the management requires understanding the relevant surgical anatomy, defining the injury via appropriate radiographic assessment and determining a suitable treatment plan. Literature is scarce for the demographic data, fracture patterns, associated injuries, management and early complications in the Indian scenario. These factors play a pivotal role in the ultimate recovery of the patients. Therefore this study was conceptualised to assess the epidemiology and evaluate the complications of these fractures. Furthermore the effects of various factors determining the quality of reduction in surgically treated patients were also assessed.MethodologyThis was a prospective observational study in which patients presenting to the advance trauma centre of our institute with acetabulum fractures were included. Demographical data of the patients, mechanisms of injuries, fractures morphologies, complications and radiological outcomes were recorded prospectively.Results116 patients with acetabular fractures were included in the study. 81% of these were males, with average age of 39.95 ± 15.87 years; with road traffic accidents being the predominant mode of injuries. Mortality was reported in 5 patients; 4 patients had deep venous thrombosis and sciatic nerve injuries were seen in 12 patients of which 4 were iatrogenic. 8 patients had some form of infection, out of which 4 required multiple debridements. 4 cases developed heterotrophic ossification while 2 cases had loss of reduction. The timing of surgery and other associated fractures had significant effect on the quality of reduction (p < 0.05); while age, gender, mode of injury or individual fracture patterns had no such effect.ConclusionsProper radiological assessment and evaluation of fracture configuration is important for management of acetabulum fractures. When indicated, this should be followed by early open reduction and internal fixation to achieve anatomical reduction, with management of associated injuries for better outcomes.  相似文献   
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