• Korean Chemical Engineering Research
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• 제53권2호
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• pp.181-192
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• 2015

본 연구는 Liquid Crystal Display (LCD) 세척 후 발생하는 Propylene Glycol Monomethyl Ether Acetate (PGMEA)폐액 재활용을 위한 2기 증류탑을 사용하는 공정의 최적 조건을 산출하였다. 공정조건 최적화 기법으로 다중회귀분석을 이용하여 1차 증류 시 Bottom 온도(BTM 온도), Reflux 량, Feed 량 및 Feed 온도에 따라 PGMEA 함량에 대한 최적 조건과 2차 증류 시 BTM 온도, Reflux 량, Feed 량에 따른 PGMEA 함량에 대한 최적 조건과 공정인자를 산출하였다. 1차 증류탑의 공정인자 중 Reflux 량, Feed 온도 및 Feed 량이 중요한 인자로 산출되었다. 본 연구의 공정조건 범위에서는 BTM 온도범위가 PGMEA함량에 크게 영향을 주지 못하였다. 따라서 최적 공정 조건은 Feed 량 $5,700{\ell}$, Reflux 량 $2,500{\ell}$, BTM 온도 $165^{\circ}C$ 및 Feed 온도 $130^{\circ}C$이며 이때 예측된 PGMEA 함량은 92.12~94.62%로 산출되었다. 2차 증류탑에서는 Reflux 량이 함량에 많은 영향을 미치고 있으며, Feed 량과 BTM 온도도 영향을 미치는 인자로 산출되었다. 다중공선성(Multicollinearity)이 Reflux 량과 BTM 온도 간에 강한 양의 상관관계가 있어, 두 인자 중 다중회귀식에 영향이 지배적인 인자 하나를 선택하였으며, 최적조건은 BTM 온도 $199^{\circ}C$ 기준에서 최적 공정 조건은 Feed 량 $4,275{\ell}$ 및 Reflux 량 $6,200{\ell}$이며, 이때 예측 PGMEA 함량은 99.0~99.5%로 산출되었다.

• Journal of Gastric Cancer
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• 제20권1호
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• pp.72-80
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• 2020

Purpose: Proximal gastrectomy (PG) is a function-preserving surgery in cases of proximally located early-stage gastric cancer. Because gastroesophageal reflux is a major pitfall of this operation, we devised a modified esophagogastrostomy (EG) anastomosis to fix the distal part of the posterior esophageal wall to the proximal part of the anterior stomach wall to produce an anti-reflux mechanism; we named this the SPADE operation. This study aimed to show demonstrate the clinical outcomes of the SPADE operation and compare them to those of previous PG cases. Materials and Methods: Case details of 56 patients who underwent PG between January 2012 and March 2018 were retrospectively reviewed: 30 underwent conventional esophagogastrostomy (CEG) anastomosis using a circular stapler, while 26 underwent the SPADE operation. Early postoperative clinical outcome-related reflux symptoms, endoscopic findings, and postoperative complications were compared in this case-control study. Results: Follow-up endoscopy showed more frequent reflux esophagitis cases in the CEG group than in the SPADE group (30% vs. 15.3%, P=0.19). Similarly, bile reflux (26.7% vs. 7.7%, P=0.08) and residual food (P=0.01) cases occurred more frequently in the CEG group than in the SPADE group. In the CEG group, 13 patients (43.3%) had mild reflux symptoms, while 3 patients (10%) had severe reflux symptoms. In the SPADE group, 3 patients (11.5%) had mild reflux symptoms, while 1 had severe reflux symptoms (absolute difference, 31.8%; 95% confidence interval, 1.11-29.64; P=0.01). Conclusions: A novel modified EG, the SPADE operation, has the potential to decrease gastroesophageal reflux following a PG.

• 대한한방내과학회지
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• 제27권4호
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• pp.991-998
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• 2006

Gastroesophageal reflux disorder (GERD) refers to reflux of gastric contents into the esophagus leading to esophagitis, reflux symptoms (e.g. heartburn, regurgitation and non-cardiac chest pain) sufficient to impair quality of life, or long term complications. Non-erosive reflux disease (NERD), a subdivision of GERD, is diagnosed when there were some reflux symptoms without esophagitis and mucosal breaks at endoscopy. We report that severe NERD symptoms and lower quality of life which have not responded to more than 6 months' western medical therapy (acid suppression) were successfully improved with traditional oriental medicine.

• 제어로봇시스템학회논문지
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• 제8권10호
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• pp.833-841
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• 2002

We develope a model that can manipulate the reflux ratio of a batch distillation process in real time for optimal operations. Firstly, reflux ratio decision model for batch distillation unit was developed using the simple short-cut method. Secondly, more detailed rigorous method was applied to improve the accuracy of the model. Based on these models, operational strategies for the optimal reflux ratio was proposed. The results are illustrated with suitable examples and compared with the results using commercial simulator.

• 대한본초학회지
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• 제35권6호
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• pp.43-53
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• 2020

Objective : Reflux esophagitis is a disease caused by reflux of stomach contents, stomach acid, and pepsin into the esophagus, and is currently increasing worldwide. This study was conducted to evaluate the effect of a mixture of Rhei Rhizoma and Scutellariae Radix (RS) extract on acute reflux esophagitis in rats. Methods : Rats were divided into five groups for examination: Normal group (Nor, n=8), water-treated acute reflux esophagitis rats (Con, n=8), tocopherol 30 mg/kg body weight/day-treated acute reflux esophagitis rats (Toco, n=8), RS 100 mg/kg body weight/day-treated acute reflux esophagitis rats (RS100, n=8), RS 200 mg/kg body weight/day-treated acute reflux esophagitis rats (RS200, n=8). All rats fasted for 18 h and then were derived by linking the metastatic junction between pylorus and forestomach and corpus. And rats were sacrificed 5 h after surgery. We analyzed the expression of NADPH, MAPK, inflammatory, anti-inflammatory, and tight junction related proteins by western blot in esophageal tissue and observed the level of reactive oxygen species (ROS), alanine aminotransferanse (ALT), and aspartate aminotransferase (AST) in serum. Results : RS administration significantly protected the esophageal mucosal damage of reflux esophagitis, and ROS, AST, and ALT levels were significantly reduced in RS administration compared to Con group. In addition, RS administration effectively suppressed MAPK and NF-κB pathways and upregulated protein expressions of tight junction protein. Conclusions : These results suggest that RS protected the esophageal mucosa by inhibiting the MAPK and NF-κB pathways and upregulating tight junctions.

• 생약학회지
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• 제52권3호
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• pp.177-185
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• 2021

Gastroesophageal reflux disease (GERD) is a gastrointestinal disorder in which stomach contents reflux into the esophagus, causing complications such as mucosal damage. The purpose of this study was to determine the effect of Rhei Rhizoma and Scutellariae Radix mixture (RS) in chronic acid reflux esophagitis (CARE), one of the GERD. After inducing reflux esophagitis through surgery, the group was separated and the drug was administered for 2 weeks; Normal rats (Normal, n=8), chronic acid reflux esophagitis rats (Control, n=8), tocopherol 30 mg/kg-treated chronic acid reflux esophagitis rats (Toco, n=8), Rhei Rhizoma and Scutellariae Radix mixture 100 mg/kg-treated chronic acid reflux esophagitis rats (RSL, n=8), Rhei Rhizoma and Scutellariae Radix mixture 200 mg/kg-treated chronic acid reflux esophagitis rats (RSH, n=8). Gross lesion of esophageal mucosa after RS treatment showed a superior enhancement compared with that of Control group. Additionally, RS significantly decreased the levels of MPO and MDA, effectively inhibited NADPH oxidase, and regulated the expression of the AMPK/LKB1/NF-κB pathway. Moreover, it significantly increased the expression of tight junction proteins. Taken together, RS not only alleviates inflammation of the esophageal mucosa via the AMPK/LKB1/NF-κB pathway by reducing oxidative stress, but also improves esophageal function by modulating tight junction proteins.

• Journal of Gastric Cancer
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• 제13권2호
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• pp.79-85
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• 2013

There is a growing evidence that gastroesophageal reflux disease is related to several upper gastrointestinal cancers, mainly the esophageal adenocarcinoma and a certain type of gastric cardia adenocarcinoma. Currently, the incidence of gastroesophageal reflux disease is rapidly increasing in Korea. Therefore, there is a possibility of such increasing cancerous incidents, similar to the western worlds. In this article, the relationship between gastroesophageal reflux disease and several upper gastrointestinal cancers, the components of refluxate which has possible causal relationship with carcinogenesis, and the clinical implications of such relationship in the management of gastroesophageal reflux disease patients are discussed through the review of literature.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.941-946
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• 1992

Three different reflux policies are compared for a batch distillation process in which a fixed recovery with a given average purity of the distillate is required ; the first, for the constant distillate purity ; the second, for the constant reflux ratio ; finally, for the optimal reflux policy which gives the minimum operation time. The optimal reflux policy was obtained using pontryagin's maximum principle. Througy the numerical simulations for the three different binary mixtures, it was found that the time advantage of the optimal reflux operation over the constant overhead composition operation varies form 10.0 to 22.4% and the advantage over the constant reflux operation varies from 1106 to 36.6% in the three cases considered.

• 대한방사선협회지
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• 제28권1호
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• pp.61-66
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• 2002

Purpose : This study presents a new classification of gastroesophageal reflux to evaluate the patients with Gastroesophageal reflux disease after barium contrast reflux exam to help making the correct diagnosis and Treatment according to the symptoms and

• 대한기관식도과학회지
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• 제16권2호
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• pp.97-104
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• 2010

Gastroesophageal reflux disease (GERD) is a common disorder caused by the reflux of gastric contents into the esophagus. According to the recent classification, GERD can elicit esophageal and extraesophageal syndromes. Laryngopharyngeal reflux (LPR) is defined as laryngeal symptoms with laryngeal inflammation caused by the acid reflux. The prevalence of GERD and LPR is increasing during the past decades in Korea and management of GERD and LPR is a challenging issue in clinical practice. Proton pump inhibitor is the most effective drug in the treatment of GERD. Most patients with LPR are given a 2-month trial of a proton pump inhibitor (PPI), however, there is still little evidence on the diagnosis or the treatment of LPR. During the last years concern have been raised regarding the risk of averse events related to long-term use of PPI. We review the recent update on medical treatment of GERD/LPR.