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941.
BackgroundIn patients with early-stage breast cancer, the treatment results of hypofractionated radiation therapy (RT) and conventional RT are evaluated in efficacy and cost.MethodsWe retrospectively evaluated 280 patients with early-stage (Tis-2N0M0) breast cancer (including 100 hypofractionated RT patients) with regards to treatment outcomes according to the RT schedule. The median whole-breast RT dose was 42.56 Gy/16 fractions for hypofractionated RT and 50.4 Gy/28 fractions for conventional RT. Most patients (n = 260, 92.9%) additionally received a tumor bed boost RT. We used propensity score matching (PSM) analysis to balance the baseline risk factors for recurrence. The co-primary endpoints of this study were disease-free survival (DFS) and ipsilateral breast tumor recurrence (IBTR). DFS or IBTR was analyzed using the Kaplan-Meier survival curve and log-rank test.ResultsTotal 89 pairs of matched patients (1:1 matching, n = 178) were finally evaluated. The median follow-up was 23.6 months. After matching, the 3-year DFS was 100% in the hypofractionated RT group and 98.4% in the conventional RT group; there was no significant difference in DFS between the groups (P = 0.374). Furthermore, the IBTR did not differ between the hypofractionated RT and conventional RT groups (P = 0.374) after matching. The 3-year overall survival was not different between two groups (both 100%). Hypofractionated RT saved 26.6% of the total cost of RT compared to conventional RT. Additionally, the acute skin toxicity rate (≥ grade 2) was also not significantly different between the groups (hypofractionated RT: 10.1% vs. conventional RT: 2.2%).ConclusionHypofractionated RT showed good IBTR and DFS, which were compatible to those in conventional RT in breast cancer. Hypofractionated RT is expected to be used more widely because of its low cost and convenience.  相似文献   
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Introduction:The prevalence of lumbosacral radiculopathy is estimated to be approximately 3% to 5% in patient populations. Lumbosacral radiculopathy is largely caused by a complex interaction between biomechanical and biochemical factors. Nerve block therapy (NBT) mainly treats lumbosacral radiculopathy by improving the biochemical factors, whereas acupotomy mainly focuses on improving the biomechanical factors. Therefore, it is thought that synergistic effects may be obtained for the treatment of lumbosacral radiculopathy when both NBT and acupotomy are combined. However, no study in China and Korea, where acupotomy is majorly provided, has reported the effects of such a combination treatment. Therefore, this study aimed to evaluate the safety, effectiveness, and cost-effectiveness of the concurrent use of a deeply inserted acupotomy and NBT for the treatment of lumbosacral radiculopathy.Methods/design:This is an open-label, parallel, assessor-blinded, randomized controlled trial, which will include 50 patients with lumbosacral radiculopathy. After patients voluntarily agree to participate in the study, they will be screened, and will undergo necessary examinations and tests according to the protocol. Those who satisfy the selection criteria will be randomly assigned to either the NBT + acupotomy or NBT groups in a 1:1 ratio. Both groups will undergo 2 NBTs once every 2 weeks from 1 week after the screening test. The treatment group will receive additional acupotomy twice a week for 4 weeks. The primary endpoint is the Oswestry Disability Index, whereas the secondary endpoints are the Numeral Rating Scale, European Quality of Life 5-dimension, McGill pain Questionnaire, Roland-Morris Disability Questionnaire, safety assessment, and economic feasibility evaluation. The measurements will be made at 0, 2, 4, and 8 weeks.Ethics and dissemination:This trial has received complete ethical approval from the Ethics Committee of Catholic Kwandong University International St. Mary''s Hospital (IS20OISE0085). We intend to submit the results of the trial to a peer-reviewed journal and/or conferences.  相似文献   
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In the past decade, perovskite materials have gained intensive interest due to their remarkable material properties in optoelectronics and photodetectors. This review highlights recent advances in micro-to-nanometer scale patterning of perovskite inks, placing an undue emphasis on recently developed approaches to harness spatially ordered and crystallographically oriented structures with unprecedented regularity via controlled self-assemblies, including blade coating, inkjet printing, and nanoimprinting. Patterning of the perovskite elements at the micro- or nanometer scale might be a key parameter for their integration in a real system. Nowadays, unconventional approaches based on irreversible solution evaporation hold an important position in the structuring and integration of perovskite materials. Herein, easier type patterning techniques based on evaporations of polymer solutions and the coffee ring effect are systematically reviewed. The recent progress in the potential applications of the patterned perovskite inks is also introduced.  相似文献   
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ObjectiveTo develop and evaluate a deep learning-based artificial intelligence (AI) model for detecting skull fractures on plain radiographs in children.Materials and MethodsThis retrospective multi-center study consisted of a development dataset acquired from two hospitals (n = 149 and 264) and an external test set (n = 95) from a third hospital. Datasets included children with head trauma who underwent both skull radiography and cranial computed tomography (CT). The development dataset was split into training, tuning, and internal test sets in a ratio of 7:1:2. The reference standard for skull fracture was cranial CT. Two radiology residents, a pediatric radiologist, and two emergency physicians participated in a two-session observer study on an external test set with and without AI assistance. We obtained the area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity along with their 95% confidence intervals (CIs).ResultsThe AI model showed an AUROC of 0.922 (95% CI, 0.842–0.969) in the internal test set and 0.870 (95% CI, 0.785–0.930) in the external test set. The model had a sensitivity of 81.1% (95% CI, 64.8%–92.0%) and specificity of 91.3% (95% CI, 79.2%–97.6%) for the internal test set and 78.9% (95% CI, 54.4%–93.9%) and 88.2% (95% CI, 78.7%–94.4%), respectively, for the external test set. With the model’s assistance, significant AUROC improvement was observed in radiology residents (pooled results) and emergency physicians (pooled results) with the difference from reading without AI assistance of 0.094 (95% CI, 0.020–0.168; p = 0.012) and 0.069 (95% CI, 0.002–0.136; p = 0.043), respectively, but not in the pediatric radiologist with the difference of 0.008 (95% CI, -0.074–0.090; p = 0.850).ConclusionA deep learning-based AI model improved the performance of inexperienced radiologists and emergency physicians in diagnosing pediatric skull fractures on plain radiographs.  相似文献   
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Background

A comparison between responses to allergens based on the TRUE Test® (TT) and IQ® Chamber (IQC) in Europeans has been previously reported, however, no such study has been performed in Asians.

Objectives

To compare allergen responses using the TT and IQC (using the Korean standard series) in order to gather more information regarding the positive response rates for each allergen and the clinical value of IQC.

Materials & methods

Suspected contact dermatitis patients were enrolled and tested with 18 allergens using the TT and IQC.

Results

The test was performed in 214 patients. Simultaneous positive results for both tests were recorded in 242 cases (positive concordance rate: 66.7%). IQC yielded more positive results. Allergens with a high positive concordance rate were nickel sulphate (82.1%), thimerosal (78.6%), and p-phenylenediamine (73.3%). IQC mostly showed similar or higher positive rates than TT, with high concordance.

Conclusions

We recommend the IQC method as a screening test in patients with suspected contact dermatitis. To compensate for possible false positive results, careful history taking and a different patch test should be performed when appropriate.
  相似文献   
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