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1.

Purpose

The purpose of this study was to build and evaluate a high-performance algorithm to detect and characterize the presence of a meniscus tear on magnetic resonance imaging examination (MRI) of the knee.

Material and methods

An algorithm was trained on a dataset of 1123 MR images of the knee. We separated the main task into three sub-tasks: first to detect the position of both horns, second to detect the presence of a tear, and last to determine the orientation of the tear. An algorithm based on fast-region convolutional neural network (CNN) and faster-region CNN, was developed to classify the tasks. The algorithm was thus used on a test dataset composed of 700 images for external validation. The performance metric was based on area under the curve (AUC) analysis for each task and a final weighted AUC encompassing the three tasks was calculated.

Results

The use of our algorithm yielded an AUC of 0.92 for the detection of the position of the two meniscal horns, of 0.94 for the presence of a meniscal tear and of 083 for determining the orientation of the tear, resulting in a final weighted AUC of 0.90.

Conclusion

We demonstrate that our algorithm based on fast-region CNN is able to detect meniscal tears and is a first step towards developing more end-to-end artificial intelligence-powered diagnostic tools.  相似文献   

2.

Background

The aims of this study were to identify the artery feeding the fifth metatarsal and determine how bunionette osteotomy could injure this vessel.

Methods

The nutrient artery entering the fifth metatarsal was investigated in 10 adult cadaveric lower limbs by barium injection and enhanced computed tomography.

Results

The nutrient artery entered the medial aspect of the fifth metatarsal around the junction of the middle and proximal thirds obliquely from a distal direction (mean?angle 36°) in the coronal plane in all cases; in the axial plane, the point of entry and direction of the artery was medial-plantar (mean?angle 49°).

Conclusions

This report revealed direction and location of the nutrient artery entering the fifth metatarsal.  相似文献   

3.

Purpose

The purpose of this study was to create an algorithm that simultaneously detects and characterizes (benign vs. malignant) focal liver lesion (FLL) using deep learning.

Materials and methods

We trained our algorithm on a dataset proposed during a data challenge organized at the 2018 Journées Francophones de Radiologie. The dataset was composed of 367 two-dimensional ultrasound images from 367 individual livers, captured at various institutions. The algorithm was guided using an attention mechanism with annotations made by a radiologist. The algorithm was then tested on a new data set from 177 patients.

Results

The models reached mean ROC-AUC scores of 0.935 for FLL detection and 0.916 for FLL characterization over three shuffled three-fold cross-validations performed with the training data. On the new dataset of 177 patients, our models reached a weighted mean ROC-AUC scores of 0.891 for seven different tasks.

Conclusion

This study that uses a supervised-attention mechanism focused on FLL detection and characterization from liver ultrasound images. This method could prove to be highly relevant for medical imaging once validated on a larger independent cohort.  相似文献   

4.

Purpose

This work presents our contribution to one of the data challenges organized by the French Radiology Society during the Journées Francophones de Radiologie. This challenge consisted in segmenting the kidney cortex from coronal computed tomography (CT) images, cropped around the cortex.

Materials and methods

We chose to train an ensemble of fully-convolutional networks and to aggregate their prediction at test time to perform the segmentation. An image database was made available in 3 batches. A first training batch of 250 images with segmentation masks was provided by the challenge organizers one month before the conference. An additional training batch of 247 pairs was shared when the conference began. Participants were ranked using a Dice score.

Results

The segmentation results of our algorithm match the renal cortex with a good precision. Our strategy yielded a Dice score of 0.867, ranking us first in the data challenge.

Conclusion

The proposed solution provides robust and accurate automatic segmentations of the renal cortex in CT images although the precision of the provided reference segmentations seemed to set a low upper bound on the numerical performance. However, this process should be applied in 3D to quantify the renal cortex volume, which would require a marked labelling effort to train the networks.  相似文献   

5.
Yufeng Zhou  Kai Yang 《Injury》2019,50(3):633-638

Introduction

Surgery or trauma may induce extensive arthrofibrosis around joints and tendon for the restrictive range of motion. Although some approaches were proposed, this problem is not solved satisfactorily. Extracorporeal shock wave therapy (ESWT) has been used for orthopedic, musculoskeletal, and fibrotic disorders. Whether it could prevent the formation of arthrofibrosis during the joint repair is unknown.

Methods

Intra-articular adhesions were created in the right knee of the rabbit by cortical bone shaving and subsequent cast immobilization. Arthrofibrosis in the control and ESWT group was evaluated and compared at week 4.

Results

Macroscopic score of arthrofibrosis and contracture angle of the control group are significantly higher. Histologically, the apparent gap between patella and tibia, loose connective tissue, and much less density of the blood vessel are found in the ESWT group.

Conclusions

ESWT could noninvasively, effectively, and safely prevent the formation of arthrofibrosis during the knee repair.  相似文献   

6.

Purpose

The purpose of this study was to assess the potential of a deep learning model to discriminate between benign and malignant breast lesions using magnetic resonance imaging (MRI) and characterize different histological subtypes of breast lesions.

Materials and methods

We developed a deep learning model that simultaneously learns to detect lesions and characterize them. We created a lesion-characterization model based on a single two-dimensional T1-weighted fat suppressed MR image obtained after intravenous administration of a gadolinium chelate selected by radiologists. The data included 335 MR images from 335 patients, representing 17 different histological subtypes of breast lesions grouped into four categories (mammary gland, benign lesions, invasive ductal carcinoma and other malignant lesions). Algorithm performance was evaluated on an independent test set of 168 MR images using weighted sums of the area under the curve (AUC) scores.

Results

We obtained a cross-validation score of 0.817 weighted average receiver operating characteristic (ROC)-AUC on the training set computed as the mean of three-shuffle three-fold cross-validation. Our model reached a weighted mean AUC of 0.816 on the independent challenge test set.

Conclusion

This study shows good performance of a supervised-attention model with deep learning for breast MRI. This method should be validated on a larger and independent cohort.  相似文献   

7.

Introduction

Horse racing is a hazardous sport. We analyzed the incidence and characteristics of jockey injuries in a typical horse race.

Methods

We analyzed all injuries sustained by 224 jockeys in the last 72 years.

Results

It was found that in 96.1% of the races there was at least one fall and in 28.6% of the races 50% or more of the jockeys fell. In 43.4% of the falls, the jockey was taken to the emergency room. Comparing the Palio with traditional races in other countries, a higher injury incidence rate was observed for every 100 falls (109.884 vs 27–59) and a lower concussion rate/100 falls (0.97 vs 1.8-7.4).

Conclusion

The Palio is one of the most threatening races that continues today. Jockeys are at greater risk for a fall than any other race in the world.  相似文献   

8.
9.

Objective

To analyse whether early post-operative full weight bearing following syndesmotic ankle fixation affected radiographic outcomes suggestive of diastasis.

Design

Retrospective comparative cohort study over a two year period.

Setting

Level 1 trauma centre

Patients/Participants

152 consecutive patients sustaining an unstable ankle fracture requiring syndesmotic stabilisation were included. Exclusions were 49 patients who had trimalleolar fixation without syndesmosis screws, one patient who had concomitant ankle and talar fracture. Five patients were lost to follow up and eleven patients were followed up in other centres. A total of 86 patients were analysed

Intervention

Protected or full weight bearing.

Main Outcome Measurement

The primary outcome measure was early diastasis. The secondary outcomes were late diastasis, wound complications and re-operation. Analysis of variance was used for the predictor variable of weight bearing status. We assumed a priori that p values of less than 0.05 were significant.

Results

Median age was 36 (IQR 30), with 54 males and 32 females. Median follow up was 12 weeks (IQR 6). There was no significant difference when comparing weight bearing status and change in radiographic measurements intra-operatively compared to 6 and 12 week follow up radiographs (tibiofibular clear space p?=?0.799, tibiofibular overlap p?=?0.733 and medial clear space p?=?0.261).

Conclusion

After surgical stabilization of an unstable syndesmotic injury, full weight bearing did not lead to syndesmotic diastasis in the early post-operative period. Full weight bearing is recommended following ankle fixation which includes syndesmotic fixation.  相似文献   

10.

Objectives

Hip dislocations are highly morbid injuries necessitating prompt reduction and post-reduction assessment for fracture and incarcerated fragments. Recent literature has questioned the need for initial pelvic radiographs for acute trauma patients, resulting in computed tomography (CT) scans as the initial evaluation. This study investigates the relationship between choice of pre-reduction imaging and treatment of acute hip dislocations.

Design

Retrospective Case-Control.

Setting

Single Academic Level I Trauma Center.

Methods

All acute hip dislocations from 2011 to 2016 were reviewed. Exclusion criteria were diagnosis of dislocation at another facility, death prior to reduction, emergent surgical or ICU intervention, and periprosthetic dislocation. Patients were grouped by those with only a radiograph prior to reduction, Group I, versus those with a pre-reduction CT scan, Group II. The primary outcomes were time to reduction and the acquisition of a second CT scan.

Results

Of the 123 hip dislocations identified, 35 patients were excluded, mostly for transfer with a known dislocation. Group I included 29 patients and Group II included 59 patients. The mean time to reduction was 74?min in Group I and 129?min in Group II for a difference of 55?min (p?<?0.001). The rate of repeat CT scan was 0 in Group I versus 48 (81%) in Group II (p?<?0.001).

Conclusion

Initial trauma pelvic radiography prior to CT is still important in the setting of suspected hip pathology to decrease time to hip reduction and unnecessary radiation exposure.

Level of evidence

Prognostic Level III.  相似文献   

11.

Purpose

The purpose of this study was to report the feasibility of computed modelization and reconstitution of the paranasal sinuses, before and after trauma, from CT data.

Materials and methods

We modeled and reconstructed the paranasal sinuses of two patients (A and B), before and after trauma, using two different softwares (3DSlicer® and Blender®). Both patients had different numbers and locations of fractures. The 3DSlicer® software was used to create a 3D model from CT data. We then imported the 3D data into the Blender® software, to reconstruct and compare the dimensions of the paranasal sinuses before and after trauma.

Results

The 3 fragments of patient A and the 7 fragments of patient B could be repositioned in the pre-traumatic configuration. Distance measurements proved to be similar between pre- and post-traumatic 3D volumes.

Conclusion

After simple trauma, bone facial anatomy reconstruction is manually feasible. The whole procedure could benefit from automatization through machine learning. However, this feasibility must be confirmed on more severely fractured paranasal sinuses, to consider an application in forensic identification.  相似文献   

12.

Context

The European Association of Urology Renal Cell Carcinoma (RCC) Guideline Panel has prepared evidence-based guidelines and recommendations for the management of RCC.

Objective

To provide an updated RCC guideline based on standardised methodology including systematic reviews, which is robust, transparent, reproducible, and reliable.

Evidence acquisition

For the 2019 update, evidence synthesis was undertaken based on a comprehensive and structured literature assessment for new and relevant data. Where necessary, formal systematic reviews adhering to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were undertaken. Relevant databases (Medline, Cochrane Libraries, trial registries, conference proceedings) were searched until June 2018, including randomised controlled trials (RCTs) and retrospective or controlled studies with a comparator arm, systematic reviews, and meta-analyses. Where relevant, risk of bias (RoB) assessment, and qualitative and quantitative syntheses of the evidence were performed. The remaining sections of the document were updated following a structured literature assessment. Clinical practice recommendations were developed and issued based on the modified GRADE framework.

Evidence synthesis

All chapters of the RCC guidelines were updated based on a structured literature assessment, for prioritised topics based on the availability of robust data. For RCTs, RoB was low across studies. For most non-RCTs, clinical and methodological heterogeneity prevented pooling of data. The majority of included studies were retrospective with matched or unmatched cohorts, based on single- or multi-institutional data or national registries. The exception was for the treatment of metastatic RCC, for which there were several large RCTs, resulting in recommendations based on higher levels of evidence.

Conclusions

The 2019 RCC guidelines have been updated by the multidisciplinary panel using the highest methodological standards. These guidelines provide the most reliable contemporary evidence base for the management of RCC in 2019.

Patient summary

The European Association of Urology Renal Cell Carcinoma Guideline Panel has thoroughly evaluated the available research data on kidney cancer to establish international standards for the care of kidney cancer patients.  相似文献   

13.

Background

Few methods have been described for measuring hindfoot alignment from an anteroposterior view. The objective of this study was to compare two methods of angular measurement based on the views of Meary and Saltzman.

Methods

Thirty asymptomatic volunteers were included. Four radiographs were performed: the views of Meary and Saltzman with parallel feet and with the Fick correction. The reproducibility was determined by the inter- and intraobserver variability (ICC).

Results

Meary’s method revealed a mean valgus angulation of 3.9° (SD 3.47°). The reliability was extremely variable with a mean ICC of 0.59. The best reproducibility was obtained with Meary’s method with and without Fick correction.

Conclusion

The results of this study show that the reliability of the angular measurements depends on the radiographic view and measurement method chosen. The lateral Fick correction did not counteract the influence of tibial rotation. The same method should be used consistently.  相似文献   

14.

Introduction

Acute lateral patellar dislocation is a very common condition in orthopedics, especially among adolescents and physically active patients. To evaluate distinct medial patellofemoral ligament (MPFL) injury patterns and the associated knee pathology after acute lateral patellar dislocation (ALPD) using magnetic resonance imaging (MRI) studies, which is essential for the development of treatment protocols.

Materials and Methods

MRI images of 74 ALPD patients were taken between January 2015 to December 2016. Images were evaluated using standardized protocols.

Results

The prevalence of MPFL injury following ALPD was 97.3% (72/74 patients). Among the 72 patients with MPFL, the prevalence of Type Ⅰ injury was 26.4% (19/72). Since only bone marrow edema and a partial tear were showed on MRI of these patients, conservative treatment was given. Tear of the MPFL occurred at the patellar attachment (Type Ⅱa) in 16 patients (16/72, 22.2%), at the middle area of the ligament (Type Ⅱb) in 5 patients (5/72, 6.9%), and at the femoral attachment (Type Ⅱc) in 27 patients (27/72, 37.5%). For Type Ⅱ injuries, all patients had the surgery to reconstruct the MPFL. The prevalence of Type Ⅲ MPFL injury was 6.9% (5/72) after the surgery.

Conclusion

MPFL injury of is a common sequel following ALPD. We assessed the distinct injury pattern and associated pathology of MPFL using MRI studies. A good understanding of the injury pattern and associated knee pathology of MPFL is essential in managing patients with ALPD, especially if surgical intervention is considered.  相似文献   

15.
Mengmeng Du  Jiuhui Han 《Injury》2019,50(2):598-601

Background and purpose

The treatment of paediatric distal radius diaphyseal metaphyseal junction (DRDMJ) fractures is a challenge. The purpose of this study was to introduce a new operative approach at the proximal “safe zone” of the posterior interosseous nerve (PIN) to treat paediatric DRDMJ fractures and analyse the safety and efficacy of antegrade elastic stable intramedullary nail (ESIN) fixation.

Methods

Thirty paediatric patients with unstable and displaced DRDMJ fractures were treated by antegrade ESIN fixation from November 2015 to September 2017. We created the entrance site at the posterolateral side of the proximal radius and 2?4?cm distal to the articular surface of the radius, using the ESIN to immobilise the fractures. In the study, we reviewed patient demographics, complications, time until removal, and intraoperative time for hardware removal.

Results

Complete fracture healing was achieved between 6 and 12 weeks after surgery. Except for 3 patients presenting with irritation of the skin, we did not observe any complications. Radiologically, no secondary displacement, nail migration, loss of fixation, consolidation delay, non-union, or refracture was noted.

Conclusions

The antegrade ESIN fixation is a minimally invasive, easy-to-learn, alternative operative method to treat paediatric DRDMJ fractures.

Level of evidence

Therapeutic Level IV.  相似文献   

16.

Background

Patient-reported outcome measures (PROMs) have become widely adopted in the care of patients with prostate cancer, but there is no validated crosswalk between two commonly used instruments, the Expanded Prostate Cancer Index Composite Short Form (EPIC-26) and the Memorial Sloan Kettering (MSK) instrument, which consists of the International Index of Erectile Function-6 (IIEF-6) questionnaire and the MSK radical prostatectomy urinary outcome scale.

Objective

To develop and validate bidirectional crosswalks between the sexual and urinary domains (single domain in MSK, separate incontinence and irritative/obstructive domains in EPIC-26) of the MSK and EPIC-26 instruments.

Design, setting, and participants

Radical prostatectomy (RP) patients completing instruments at MSK and Michigan Urological Surgery Improvement Collaborative (MUSIC) between January and May of 2017 were invited to enroll. Stratified random sampling (by institution, MSK urinary function score, and MSK erectile function score) was used to divide patient data into training and test sets. Models were developed to predict the domain score for each instrument using the other's item responses and domain scores. Performance was evaluated using capped root-mean-squared error and accuracy at established thresholds.

Results and limitations

We received 517 instruments at MSK and 1033 within MUSIC, which were assigned to training (825), post-RP test (412), and pre-RP test (313) sets. We found the crosswalks to have low error and high accuracy. Although the crosswalks are more accurate if responses to each item are known, it is possible to convert between instruments on the basis of a total domain score.

Conclusions

The crosswalks are a valid way to convert between sexual and urinary domains of the MSK and EPIC-26 instruments.

Patient summary

We developed and validated a set of formulas that allow conversion of sexual and urinary function scores between the Memorial Sloan Kettering and Expanded Prostate Cancer Index Composite Short Form patient-reported outcome questionnaires. These crosswalks allow seamless transition between the two questionnaires.  相似文献   

17.

Context

Empiric use of medical and nutritional supplements to improve semen parameters and pregnancy rates in couples with idiopathic infertility has reached global proportions, although the evidence base for their use in this setting is controversial.

Objective

We systematically reviewed evidence comparing the benefits of nutritional and medical therapy on pregnancy rates and semen parameters in men with idiopathic infertility.

Evidence acquisition

A literature search was performed using MEDLINE, Embase, LILACS, and the Cochrane Library (searched from January 1, 1990 to September 19, 2017). using the methods detailed in the Cochrane Handbook. Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to assess the certainty of evidence.

Evidence synthesis

The literature search identified 5663 citations, and after screening of abstracts and full texts, 61 studies (59 randomised controlled trials and two nonrandomised comparative studies) were included. Pooled results demonstrated that pentoxyfylline, coenzyme Q10, L-carnitine, follicle-stimulating hormone, tamoxifen, and kallikrein all resulted in improvements in semen parameters. Individual studies identified several other medical and nutritional therapies that improved semen parameters, but data were limited to individual studies with inherent methodological flaws. There were limited data available on live birth and pregnancy rates for all interventions. The GRADE certainty of evidence for all outcomes was very low mainly owing to methodological flaws and inconsistencies in study design. Some outcomes were also downgraded owing to imprecision of results.

Conclusions

There is some evidence that empiric medical and nutritional supplements may improve semen parameters. There is very limited evidence that empiric therapy leads to better live birth rates, spontaneous pregnancy, or pregnancy following assisted-reproductive techniques. However, the findings should be interpreted with caution as there were some methodological flaws, as a number of studies were judged to be either at high or unclear risk of bias for many domains.

Patient summary

This review identified several medical and nutritional treatments, such as pentoxyfylline, coenzyme Q10, L-carnitine, follicle-stimulating hormone, tamoxifen, and kallikrein, that appear to improve semen parameters. However, there are limited data suggesting improvements in pregnancy and live birth rates. The lack of evidence can be attributed to methodological flaws in studies and the low number of pregnancies reported.  相似文献   

18.

Introduction

The management of long bone lower limb fractures secondary to gunshot wounds (GSWs) in the civilian setting are complex and there is currently no consensus regarding the optimal approach to managing such fractures. This study aims to address the relationship of implant related sepsis in fractures secondary to GSWs.

Methods

A systematic review of the literature was performed on both Pubmed and Scopus databases that look at fractures caused by GSWs in the lower limb. A total of 14 studies met the inclusion criteria set in this study.

Results

Current literature suggests that low and high velocity injuries managed with internal fixation, such as intramedullary nails, may carry a low risk of superficial and deep infection, with no obvious risk of osteomyelitis. However, infection was poorly defined across all studies and no study used a validated scoring system for infection making it difficult to draw any valid conclusion on the rate of infection following internal fixation of lower limb fractures following both high and low velocity GSWs.

Conclusion

There is no clear evidence to confirm or refute that internal fixation is the ideal method of management in these complex injuries and guidance is needed due to the high and increasing proportion of patients presenting with these complex injuries worldwide.  相似文献   

19.

Background

Understanding physician-level discrepancies is increasingly a target of US healthcare reform for the delivery of quality-focused patient care.

Objective

To estimate the relative contributions of patient and surgeon characteristics to the variability in key outcomes after partial nephrectomy (PN).

Design, setting, and participants

Retrospective review of 1461 patients undergoing PN performed by 19 surgeons between 2011 and 2016 at a tertiary care referral center.

Intervention

PN for a renal mass.

Outcomes measurements and statistical analysis

Hierarchical linear and logistic regression models were built to determine the percentage variability contributed by fixed patient and surgeon factors on peri- and postoperative outcomes. Residual between- and within-surgeon variability was calculated while adjusting for fixed factors.

Results and limitations

On null hierarchical models, there was significant between-surgeon variability in operative time, estimated blood loss (EBL), ischemia time, excisional volume loss, length of stay, positive margins, Clavien complications, and 30-d readmission rate (all p < 0.001), but not chronic kidney disease upstaging (p = 0.47) or percentage preservation of glomerular filtration rate (p = 0.49). Patient factors explained 82% of the variability in excisional volume loss and 0–32% of the variability in the remainder of outcomes. Quantifiable surgeon factors explained modest amounts (10–40%) of variability in intraoperative outcomes, and noteworthy amounts of variability (90–100%) in margin rates and patient morbidity outcomes. Immeasurable surgeon factors explained the residual variability in operative time (27%), EBL (6%), and ischemia time (31%).

Conclusions

There is significant between-surgeon variability in outcomes after PN, even after adjusting for patient characteristics. While renal functional outcomes are consistent across surgeons, measured and unmeasured surgeon factors account for 18–100% of variability of the remaining peri- and postoperative variables. With the increasing utilization of value-based medicine, this has important implications for the goal of optimizing patient care.

Patient summary

We reviewed our institutional database on partial nephrectomy performed for renal cancer. We found significant variability between surgeons for key outcomes after the intervention, even after adjusting for patient characteristics.  相似文献   

20.

Background

Multiparametric magnetic resonance imaging (mpMRI) undoubtedly affects the diagnosis and treatment of localized prostate cancer (CaP). However, clinicians need a better understanding of its accuracy and limitations in detecting individual CaP foci to optimize management.

Objective

To determine the per-lesion detection rate for CaP foci by mpMRI and identify predictors of tumor detection.

Design, setting, and participants

We carried out a retrospective analysis of a prospectively managed database correlating lesion-specific results from mpMRI co-registered with whole-mount pathology (WMP) prostatectomy specimens from June 2010 to February 2018. Participants include 588 consecutive patients with biopsy-proven CaP undergoing 3-T mpMRI before radical prostatectomy at a single tertiary institution.

Outcome measurements and statistical analysis

We measured mpMRI sensitivity in detecting individual CaP and clinically significant (any Gleason score ≥7) CaP foci and predictors of tumor detection using multivariate analysis.

Results and limitations

The final analysis included 1213 pathologically confirmed tumor foci in 588 patients with primarily intermediate- (75%) or high-risk (12%) CaP. mpMRI detected 45% of all lesions (95% confidence interval [CI] 42–47%), including 65% of clinically significant lesions (95% CI 61–69%) and nearly 80% of high-grade tumors. Some 74% and 31% of missed solitary and multifocal tumors, respectively, were clinically significant. The majority of missed lesions were small (61.1% ≤1 cm); 28.3% were between 1 and 2 cm, and 10.4% were >2 cm. mpMRI missed at least one clinically significant focus in 34% of patients overall, and in 45% of men with multifocal lesions. On multivariate analysis, smaller, low-grade, multifocal, nonindex tumors with lower prostate-specific antigen density were more likely to be missed. Limitations include selection bias in a prostatectomy cohort, lack of specificity data, an imperfect co-registration process, and uncertain clinical significance for undetected lesions.

Conclusions

mpMRI detects less than half of all and less than two-thirds of clinically significant CaP foci. The moderate per-lesion sensitivity and significant proportion of men with undetected tumor foci demonstrate the current limitations of mpMRI.

Patient summary

Magnetic resonance imaging of the prostate before surgical removal for prostate cancer finds less than half of all individual prostate cancer tumors. Large, solitary, aggressive tumors are more likely to be visualized on imaging.  相似文献   

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