In this work, thermally healable graphene-nanoplate/epoxy (GNP/EP) nanocomposites were investigated. GNPs were used as reinforcement and crosslinking platforms for the diglycidyl ether of bisphenol A-based epoxy resin (DGEBA) through the Diels-Alder (DA) reaction with furfurylamine (FA). The GNPs and FA could then be used as a derivative of diene and dienophile in the DA reaction.
View Article and Find Full Text PDFThermally self-healing graphene-nanoplate/polyurethane (GNP/PU) nanocomposites were prepared via a bulk in-situ Diels⁻Alder (DA) reaction. Graphene-nanoplate (GNP) was used as a reinforcement and crosslinking platform by a DA reaction with a furfuryl-based chain extender of polyurethane (PU). Results showed that a DA reaction occurred in GNP during the PU forming cure process.
View Article and Find Full Text PDFIn this study, a highly concentrated graphite nanoplate (GNP)/polyol masterbatch was prepared by the exfoliation of natural graphite in an aqueous system using cetyltrimethylammonium bromide and the replacement of aqueous solution with a polyol, viz. poly(tetramethylene ether glycol), and it was subsequently used to prepare polyurethane (PU) nanocomposites by simple dilution. The polyol in the masterbatch efficiently prevented the aggregation of GNPs during the preparation of PU nanocomposite.
View Article and Find Full Text PDFEndoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has become one of the most useful diagnostic modalities for the diagnosis of pancreatic mass. The aim of this study was to investigate the role of analyzing the minimal specimens obtained by EUS-FNA for the diagnosis of solid masses of pancreas.This study consisted of retrospective and prospective analyses.
View Article and Find Full Text PDFParagonimiasis has been continuously decreasing in Korea. However, it still occurs by ingesting raw or incompletely cooked fresh water crab or crayfish. The diagnosis of paragonimiasis is challenging because of its rarity.
View Article and Find Full Text PDFBackground/aims: In South Korea, health check-ups are readily accessible to the public. We aimed to compare the prevalence of upper gastrointestinal (GI) and lower GI diseases in Korean Americans and native Koreans to determine differences and risk factors.
Methods: In total, 1,942 subjects who visited Gangnam Severance Hospital from July 2008 to November 2010 for a health check-up were enrolled.
Background/aims: Current international guidelines recommend colorectal cancer screening for average-risk people over 50 years of age. Accordingly, we aimed to estimate the prevalence of colorectal neoplasms in all age groups and evaluate associated risk factors.
Methods: Data of 14,932 subjects who underwent colonoscopy from July 2006 to January 2012 at Health Promotion Center, Gangnam Severance Hospital (Seoul, Korea) as part of a health check-up were reviewed retrospectively.
Objectives: Routine application of positron emission tomography/computed tomography (PET/CT) for pancreatic cancer staging remains a controversial approach. The purpose of this study was to reassess the clinical impact of PET/CT for the detection of distant metastasis of pancreatic cancer.
Methods: From January 2006 to June 2009, 125 patients with histologically proven pancreatic cancer that had undergone PET/CT at our hospital were retrospectively reviewed.
Korean autoimmune pancreatitis (AIP) criteria 2007 was aimed to diagnose the wide spectrum of AIP with high sensitivity. The most crucial issue when caring for patients with suspected AIP is to differentiate AIP from pancreatic cancer. Pancreatic cancer can be distinguished from AIP by pancreatic imaging, measurement of serum IgG4 levels, endoscopic ultrasound guided fine needle aspiration and trucut biopsy, and steroid trial.
View Article and Find Full Text PDFWorld J Gastroenterol
February 2009
Solitary pancreatic involvement of tuberculosis is rare, especially in an immunocompetent individual, and it may be misdiagnosed as pancreatic cystic neoplasms. Pancreatic cystic neoplasms are being identified in increasing numbers, probably because of the frequent use of radiology and advances in endoscopic techniques. However, they are composed of a variety of neoplasms with a wide range of malignant potential, and it is often difficult to differentiate pancreatic tuberculosis mimicking cystic neoplasms from benign or malignant pancreatic cystic neoplasms.
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