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141.
Context/Objective: The examination for Spinal Cord Injury (SCI) Medicine subspecialty certification has been administered since 1998, but published information about exam performance or administration is limited.

Design: Retrospective review

Setting/Participants: We examined de-identified information from the American Board of Physical Medicine and Rehabilitation (ABPMR) database for characteristics and performance of candidates (n?=?566) who completed the SCI Medicine Examination over a 10-year period (2005–2014), during which the exam outline and passing standard remained consistent.

Interventions: Not applicable

Outcome Measures: We analysed candidate performance by candidate track, primary specialty, number of attempts, and domains being tested. We also examined candidate perception of the SCI Medicine Exam by analysing responses to a survey taken after exam completion.

Results: Thirty-six percent of candidates who completed the exam during the study period took it for initial certification (23% in the fellowship track and 13% in the practice track offered during the initial “grandfathering” period) and 64% took it for maintenance of certification (MOC) in SCI Medicine. Factors associated with better exam performance included primary specialty certification in Physical Medicine and Rehabilitation (PM&R) and first attempt at passing the exam. For PM&R candidates, ABPMR Part I Examination scores and SCI Medicine Examination scores were strongly correlated. Candidate feedback about the exam was largely positive with 97% agreeing or strongly agreeing that it was relevant to the field and 90% that it was a good test of their knowledge.

Conclusion: This study can inform prospective candidates for the SCI Medicine Examination as well as those guiding them. It may also provide useful information for future exam development.  相似文献   
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INTRODUCTIONTraumatic abdominal wall hernia (TAWH) is a rare entity. Most cases occur in children, following an injury from the bicycle handle bar. In adults, it usually results from road traffic accidents (RTA). We present one of the largest reported cases of TAWH following RTA managed by delayed mesh repair.PRESENTATION OF CASEA 35 yr old obese male with RTA was diagnosed with TAWH with 19 cm × 15 cm defect in left flank. As there were no intra abdominal injuries and overlying skin was abraded, he was planned for elective repair after 6 months. On exploration a defect of 30 cm × 45 cm was found extending from midline anteriorly to 8 cm short of midline posteriorly in transverse axis and costal margin to iliac crest in craniocaudal axis. After restoration of bowel into abdominal cavity, primary closure or even approximation of muscular defect was not possible thus a mesh closure using 60 cm × 60 cm prolene mesh in subcutaneous plane was done. After 4 months follow up, patient is healthy and has no recurrence.DISCUSSIONEmergent surgical management of TAWH is usually favoured due to high incidence of associated intra abdominal injuries. Delayed repair may be undertaken in selected cases.CONCLUSIONTAWH, although rare, should be suspected in cases of RTA with abdominal wall swellings. With time, the hernia defect may enlarge and muscles may undergo atrophy making delayed repair difficult.  相似文献   
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Introduction

Virtual reality simulation is a promising alternative to training surgical residents outside the operating room. It is also a useful aide to anatomic study, residency training, surgical rehearsal, credentialing, and recertification.

Discussion

Surgical simulation is based on a virtual reality with varying degrees of immersion and realism. Simulators provide a no-risk environment for harmless and repeatable practice. Virtual reality has three main components of simulation: graphics/volume rendering, model behavior/tissue deformation, and haptic feedback. The challenge of accurately simulating the forces and tactile sensations experienced in neurosurgery limits the sophistication of a virtual simulator. The limited haptic feedback available in minimally invasive neurosurgery makes it a favorable subject for simulation.

Conclusions

Virtual simulators with realistic graphics and force feedback have been developed for ventriculostomy, intraventricular surgery, and transsphenoidal pituitary surgery, thus allowing preoperative study of the individual anatomy and increasing the safety of the procedure. The authors also present experiences with their own virtual simulation of endoscopic third ventriculostomy.  相似文献   
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Context:

Visual evoked potentials are useful in investigating the physiology and pathophysiology of the human visual system. Flash visual evoked potential (FVEP), though technically easier, has less clinical utility because it shows great variations in both latency and amplitude for normal subjects.

Aim:

To study the effect of eye closure, low luminance, and monochromatic stimulation on the variability of FVEPs.

Subjects and Methods:

Subjects in self-reported good health in the age group of 18-30 years were divided into three groups. All participants underwent FVEP recording with eyes open and with white light at 0.6 J luminance (standard technique). Next recording was done in group 1 with closed eyes, group 2 with 1.2 and 20 J luminance, and group 3 with red and blue lights, while keeping all the other parameters constant. Two trials were given for each eye, for each technique. The same procedure was repeated at the same clock time on the following day.

Statistical Analysis:

Variation in FVEP latencies between the individuals (interindividual variability) and the variations within the same individual for four trials (intraindividual variability) were assessed using coefficient of variance (COV). The technique with lower COV was considered the better method.

Results:

Recording done with closed eyes, 0.6 J luminance, and monochromatic light (blue > red) showed lower interindividual and intraindividual variability in P2 and N2 as compared to standard techniques.

Conclusions:

Low luminance flash stimulations and monochromatic light will reduce FVEP latency variability and may be clinically useful modifications of FVEP recording technique.Key Words: Eye closure, flash visual evoked potentials, latency variability, luminance, monochromatic light, visual evoked potentials  相似文献   
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Nanomaterials have recently gained significant interest as they are believed to offer an outstanding prospect for use in environmental remediation. Among many possible candidates, due to their useful properties including magnetic nature, wide surface area, and high absorptivity, ferrite materials hold tremendous appeal, allowing them to be used for multifaceted applications. In the present study, using a sol–gel auto combustion process, a magnetically separable Zn1−xCo0.5xMg0.5xFe2O4 (x = 0.0, 0.25, 0.50, 0.75, 1.0) ferrite with superior photocatalytic activity for dye degradation was manufactured. Rietveld refinement and FTIR studies confirm that a single-phase cubic spinel system was built for all samples with crystallite sizes of 34–57 nm. VSM has determined the magnetic properties of the samples at room temperature. With the introduction of Mg2+ and Co2+ in the Zn ferrites, a transformation from the soft superparamagnetic activity to the hard ferromagnetic character was reported. Considering the band structure in the visible region, the photocatalytic activities of the Zn1−xCo0.5xMg0.5xFe2O4 ferrites for the degradation of the MB dye under natural sunlight were investigated. Zn0.25Co0.375Mg0.375Fe2O4 showed an efficiency of degradation of 99.23% for MB dye with a quick 40 min irradiation period with high reusability of up to four cycles.

Nanomaterials have recently gained significant interest as they are believed to offer an outstanding prospect for use in environmental remediation.  相似文献   
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