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This study aimed to compare the efficiency of root canal filling procedures and the retrievability of the filling material with various sealers. Forty‐three patients assigned to endodontic treatment with (i) continuous wave of condensation technique (CTW) with AH‐plus (ii) single‐cone technique (SCT) with EndoSeal MTA. The spent time, voids entrapping and postoperative symptoms were evaluated. To evaluate the retrievability, mandibular premolar (= 60) were divided into four groups: AH‐plus/CTW, EndoSeal MTA/SCT, MTA Fillapex/SCT and EndoSequence BC Sealer/SCT. The time required removing the filled materials and remnant score were examined. EndoSeal MTA/SCT showed significantly shorter time of filling procedure. The number of void did not show significant differences between two techniques. No patients showed clinical signs during the follow‐up periods. There were no significant differences between group AH‐plus and EndoSeal MTA for remnant score. A certain calcium silicate‐based sealer with SCT may give similar clinical efficiencies as much as continuous‐wave technique using AH‐plus sealer.  相似文献   
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Background and Aim

The risk of cancer varies with the subtype of colorectal “laterally spreading tumors” (LSTs). However, visual interpretations vary among endoscopists. The aim of this study was to evaluate inter-observer agreement and accuracy in the endoscopic classification of LST subtypes among experts and trainees.

Methods

In total, 40 LST images were collected and reviewed independently by 14 gastroenterology experts and 10 trainees. All investigators recorded their findings as one of the following four categories: homogeneous, nodular mixed, flat-elevated, and pseudo-depressed. Agreement was assessed in terms of the kappa (κ) statistic and AC1 estimate. Accuracy is reported as percentage agreement with the gold standard, based on the gross morphology of the resected specimens.

Results

Of the possible 91 pair-wise κ estimates among experts, 41 (45.1 %) were >0.75, indicating excellent agreement, while only 2 (4.44 %) of the 45 pair-wise κ estimates among trainees were >0.75. Agreements for individual LST subtypes in the trainee group were significantly lower than those in the expert group. The κ and AC1 estimates showed similar values in individual subtypes of LSTs. The overall accuracy of LST was also significantly higher for the experts than the trainees (85.9 vs. 72.5 %, P < 0.001). Notably, the flat-elevated subtype showed the lowest agreement and accuracy and was frequently misclassified as the pseudo-depressed subtype by both groups.

Conclusions

Inter-observer agreement and accuracy for LST subtype classification differ significantly between experts and trainees. Implementation of an adequate training system for beginners is necessary to better identify colorectal LSTs.  相似文献   
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The crystallinities of Ag-doped poly(vinylidene fluoride) (PVDF) films were modified by removing Ag+ using a novel washing process, which allowed control of the ratio of γ- and β-phases. The polarity of the composite film without Ag+ removal through the washing process reached 98%, and the β-phase content in the total electroactive phase was increased to 61%, according to Fourier-transform infrared spectroscopy. When Ag+ were removed through a process involving several cycles of washing, filtering, drying, and re-dissolving, the highest ratio of the γ-phase was increased to 67%, 28% higher than that before washing. This showed that Ag+ induced β-phase formation while Ag nanoparticles induced γ-phase formation, and that the ratio of γ- and β-phases in PVDF composite films can be controlled to suit specific applications by this washing process.

The ratio of γ- and β-phases of Ag-doped poly(vinylidene fluoride) films was controlled by removing Ag+ using a washing process.  相似文献   
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Backgroud:Patients with gouty arthritis suffer from intermittent attacks of pain, chronic inflammation, and joint damage. Acupuncture has been used in East Asian countries for centuries to treat various diseases, and several clinical studies have reported that acupuncture has beneficial effects on gouty arthritis. This study aims to evaluate the effect of acupuncture in patients with gouty arthritis by conducting a systematic review and meta-analysis.Methods:A comprehensive search of 8 electronic databases will be performed, including MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, 4 Korean databases (KoreaMed, Korean Studies Information Service System, Research Information Service System, and Oriental Medicine Advanced Searching Integrated System), and 1 Chinese database (China National Knowledge Infrastructure). Only randomized controlled trials comparing acupuncture to conventional treatment and acupuncture with conventional treatment to conventional treatment alone for gouty arthritis will be included. Pain intensity will be considered the primary outcome. The secondary outcomes will include the pain relief duration, total effective rate, blood uric acid level, inflammatory markers, and incidence of adverse events. Two independent researchers will perform the study selection, data extraction, and quality assessment. The methodological quality of the individual included studies will be assessed using the Cochrane risk of bias tool. In the meta-analysis, for dichotomous and continuous data, risk ratios and standardized mean differences, respectively, will be estimated in addition to 95% confidence intervals.Results: This systematic review will evaluate the effect of acupuncture treatment for patients with gouty arthritis with respect to clinical symptoms, laboratory indicators, and safety.Conclusion: Our findings will help to establish the evidence of acupuncture to treat gouty arthritis.Registration number:PROSPERO CRD42020169668.  相似文献   
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Background  

Previous studies of minimal medial epicondylectomy for cubital tunnel syndrome included patients with mild disease, making it difficult to determine how much this procedure improved sensory and motor impairments in patients with moderate to severe disease.  相似文献   
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