실내사무환경의 환경성담배연기(ETS)의 지표물질에 관한 연구

하권철,백남원,박동욱,윤충식,김원,최상준,박지영,최인자,김신범,강태선 한국산업위생학회 2003 한국산업보건학회지 Vol.13 No.2

The purpose of this research is to evaluate indoor office environment using the concentrations of nicotine, 3-enthenyl-pyridine(3-EP), and respirable suspended particulate(RSP), which are indicators for environmental tobacco smoke(ETS) and the correlations between indicators and environmental conditions(smoking density, smoking index). The mean air charge per hour (ACH) in smoking rooms was 10.4 and most of the smoking rooms showed non-compliance withe ASHRAE standard value except only one smoking rooms. The concentrations of RSP, 3-EP, nicotine showed log=normal distributions, and became different statistically depending on smoking condition(p〈0.01). The geometric mean concentration of RSP in smoking room was 441.7 ug/㎡ that is far exceeded environmental standard(150 ug/㎡). This implies that fine particulate in smoking room should be carefully controlled considering smoking density and ventilation fate. The mean concentrations of nicotine and 3-EP were 93.4 ug/㎥, respectively. The correlation coefficients between RSP and SI, 3-EP and SI, and Nicotine and SI were 0.67, 0.84 and 0.74, respectively. The correlation coefficient between nicotine and 3-EP, nicotine and RSP, and RSP and 3-EP were 0.76,0.78 and 0.57 respectively.

정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

아크릴로니트릴이 극성기로 도입된 유화중합 SBR/실리카 컴파운드의 기계적 물성

김동원 ( Dong Won Kim ),서병호 ( Byeong Ho Seo ),김희정 ( Hee Jeong Kim ),백현종 ( Hyun Jong Paik ),강종원 ( Jong Won Kang ),김원호 ( Won Ho Kim ) 한국고무학회 2012 엘라스토머 및 콤포지트 Vol.47 No.1

본 연구에서는 polar 한 silica 와 non-polar 한 고무사이의 친화력을 증대시키기 위하여 SBR 분자 주쇄에 acrylonitrile 을 도입시킨 acrylonitirle functionalized emulsion SBR 의 물성에 관하여 연구하였다. Acrylonitrile의 nitrile group 은 silica 표면의 silanol group 과 H-bond 를 형성할 수 있음으로 polar 한 silica 표면에 흡착되는 가교촉진제를 줄이고 가황반응을 촉진시키는 것으로 판단된다. SBR 및 AN-SBR 에 PEG 를 적용한 컴파운드의 경우 PEG 와 silica 표면의 silanol group 과의 상용성이 높아 가교촉진제가 polar 한 silica 표면에 흡착됨을 줄여가교시간이 단축된 것으로 판단된다. 기계적 물성에서 AN-SBR 컴파운드는 SBR 1721 컴파운드 대비 100%, 300%에서 높은 모듈러스 값을 나타내었다. 이러한 결과는 AN-SBR 의 높은 분자량 및 nitrile group 의 도입에 따른 가교도의 상승에 의한 결과로 판단된다. 동적점탄특성 결과에서 AN-SBR 컴파운드는 SBR 1721 컴파운드 대비60 ℃ 에서 낮은 tan δ 값을 나타내었으며, 이는 nitrile group 과 silica 사이의 친화력에 따른 filler-rubber interaction의 향상에 의해 반복변형에 의한 energy dissipation 이 낮은 것으로 판단된다. Acrylonitrile was introduced in the emulsion SBR to increase compatibility between silica and rubber. AN-SBR/silica compounds showed faster vulcanization time and higher delta torque values than SBR 1721/silica compounds because interaction between nitrile group of AN-SBR and silanol group on the silica surface could make hydrogen bond that prevented adsorption of the accelerator on the silica surface, which improved the vulcanization reaction efficiency and enhanced the degree of crosslinking. AN-SBR/silica compound showed higher values in minimum torque than SBR 1721/silica compound during the vulcanization because AN-SBR has higher molecular weight than SBR 1721 in the raw material. When PEG was added to the SBR 1721 and AN-SBR compounds, vulcanization time was faster than SBR 1721 and AN-SBR compounds without PEG because PEG has a large number of ether linkages which show high compatibility with silanol group on the silica surface that prevented the adsorption of the accelerator and the ingredients on the silica surface, which improved the vulcanization reaction efficiency. In the mechanical properties, AN-SBR compounds showed higher modulus values at 100%, 300% than SBR 1721 compounds because interaction between nitrile group of AN-SBR and silanol group on the silica surface enhanced the degree of crosslinking. In the dynamic properties, AN-SBR compounds showed lower tan δ values at 0 ℃ than SBR 1721 compounds in accordance with the Tg values. AN-SBR compounds showed lower tan δ values at 60 ℃ than SBR 1721 compounds because interaction between acrylonitrile and silica caused strong filler-rubber interaction that induced low energy dissipation by the filler-filler interaction.

Current Practice Patterns of Endoscopic Ultrasound-Guided Tissue Sampling for Pancreatic Solid Mass in Korea: Outcomes of a National Survey

Ahn Dong-Won,Chon Hyung Ku,Moon Sung Hoon,Park Sang Wook,Paik Woo Hyun,Paik Chang Nyol,Son Byoung Kwan,Song Tae Jun,Lee Eaum Seok,Lee Yun Nah,Lee Yoon Suk,Lee Jae Min,Jeon Tae Joo,Park Chang Hwan,Cho 거트앤리버 소화기연관학회협의회 2023 Gut and Liver Vol.17 No.2

Background/Aims: Although endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) and fine needle biopsy (FNB) are widely used for tissue acquisition of pancreatic solid mass, the optimal strategy of this procedure has not been established yet. The aim of this nationwide study was to investigate the current practice patterns of EUS-FNA/FNB for pancreatic solid mass in Korea. Methods: The Policy-Quality Management of the Korean Pancreatobiliary Association (KPBA) developed a questionnaire containing 22 questions. An electronic survey consisting of the questionnaire was distributed by e-mail to members registered to the KPBA. Results: A total of 101 respondents completed the survey. Eighty respondents (79.2%) performed preoperative EUS-FNA/FNB for operable pancreatic solid mass. Acquire needles (60.4%) were used the most, followed by ProCore needles (47.5%). In terms of need size, most respondents (>80%) preferred 22-gauge needles regardless of the location of the mass. Negative suction with a 10-mL syringe (71.3%) as sampling technique was followed by stylet slow-pull (41.6%). More than three needle passes for EUS-FNA/FNB was performed by most respondents (>80%). The frequency of requiring repeated procedure was significantly higher in respondents with a low individual volume (<5 per month, p=0.001). Prophylactic antibiotics were routinely used in 39 respondents (38.6%); rapid on-site pathologic evaluation was used in 6.1%. Conclusions: According to this survey, practices of EUS-FNA/FNB for pancreatic solid mass varied substantially, some of which differed considerably from the recommendations present in existing guidelines. These results suggest that the development of evidence-based quality guidelines fitting Korean clinical practice is needed to establish the optimal strategy for this procedure.

감마분포 공정을 위한 변동계수 관리도의 통계적 설계

이동원(Dong-Won Lee),백재원(Jae-Won Paik),강창욱(Chang-Wook Kang) 한국산업경영시스템학회 2006 한국산업경영시스템학회지 Vol.29 No.2

Recently, the control chart is developed for monitoring processes with normal short production runs by the coefficient of variation(CV) characteristic for a normal distribution. This control chart does not work well in non-normal short production runs. And most of industrial processes are known to follow the non-normal distribution. Therefore, the control chart is required to be developed for monitoring the processes with non-normal short production runs by the CV characteristics for a non-normal distribution. In this paper, we suggest the control chart for monitoring the processes with a gamma short runs by the CV characteristics for a gamma distribution. This control chart is denoted by the gamma CV control chart. Futhermore evaluated the performance of the gamma CV control chart by average run length(ARL).

위선종 치료에서 내시경적 점막하 박리술과 비교한 아르곤 플라즈마 응고술의 유용성

이동현 ( Dong Hyun Lee ),배원기 ( Won Ki Bae ),김정욱 ( Jong Wook Kim ),백우현 ( Woo Hyun Paik ),김남훈 ( Nam-hoon Kim ),김경아 ( Kyung-ah Kim ),이준성 ( June Sung Lee ) 대한소화기학회 2017 대한소화기학회지 Vol.69 No.5

Background/Aims: To date, the best therapeutic modality for gastric adenoma, especially low-grade adenoma, has not been established. The aim of this study was to assess the usefulness of argon plasma coagulation (APC) in treating gastric adenoma compared with endoscopic submucosal dissection (ESD). Methods: We included 210 patients with gastric adenoma, who underwent treatment with either APC (97 patients) or ESD (113 patients). The clinical and pathologic characteristics, mean duration of hospital stay, complications, and recurrence rates between the two groups were compared. Results: The mean adenoma size was 0.9 cm and 1.1 cm in the APC group and ESD group, respectively (p<0.001). The mean duration of hospital stay was significantly shorter in the APC group than in the ESD group (1.6 days vs. 5.8 days, p<0.001). Complications did not occur in the APC group. However, one case of perforation (0.9%) and 6 cases of bleeding (5.3%) occurred in the ESD group. The recurrence rates were 15.3% (15/97 patients) in the APC group and 3.5% (4/113 patients) in the ESD group (p=0.003). The proportion of hospitalization was less in the APC group (43.3%, 42/97) than in the ESD group (100.0%, 113/113) (p<0.001). Medical expense was less in the APC group (377,172 won) than in the ESD group (1,430,610 won) (p<0.001). Conclusions: The findings of this study suggest that APC is a safe treatment method for gastric adenoma without serious complications. However, regular endoscopic follow-up is necessary to detect any residual or recurrent lesions due to the relatively high rate of local recurrence after APC. (Korean J Gastroenterol 2017;69:283-290)

Optimal Follow-up of Incidental Pancreatic Cystic Lesions without Worrisome Features: Clinical Outcome after Long-term Follow-up

Ahn Dong-Won,Lee Sang Hyub,Choi Jin Ho,Cho In Rae,Jang Dong Kee,Paik Woo Hyun,Jeong Ji Bong,Ryu Ji Kon,Kim Yong-Tae 거트앤리버 소화기연관학회협의회 2024 Gut and Liver Vol.18 No.2

Background/Aims: The optimal duration and interval of follow-up for cystic lesions of the pancreas (CLPs) is not well established. This study was performed to investigate the optimal duration and interval of follow-up for CLPs in clinical practice. Methods: Patients with CLPs without worrisome features or high-risk stigmata underwent followup with computed tomography at 6, 12, 18, and 24 months and then every 12 months thereafter. A retrospective analysis of prospectively collected data was performed. Results: A total of 227 patients with CLPs detected from 2000 to 2008 (mean initial diameter, 1.3±0.6 cm) underwent follow-up for a median of 120 months. Twenty-two patients (9.7%) underwent surgery after a median of 47.5 months. Malignancies developed in four patients (1.8%), one within 5 years and three within 10 years. One hundred and fourteen patients (50.2%) were followed up for more than 10 years. No malignancy developed after 10 years of follow-up. During surveillance, 37 patients (16.3%) experienced progression to surgical indication. In patients with CLPs less than 2 cm in diameter, development of surgical indications did not occur within 24 months of follow-up. Conclusions: CLPs should be continuously monitored after 5 years because of the persistent potential for malignant transformation of CLPs. An interval of 24 months for initial follow-up might be enough for CLPs with initial size of less than 2 cm in clinical practice.

A . C . 통전 열간압축법에 의한 n형 95%Bi2Te3 + 5% Bi2Se3 열전재료의 열전특성

백동규,김익수,황창원 대한금속재료학회(대한금속학회) 1998 대한금속·재료학회지 Vol.36 No.4

The n-type thermoelectric material of 95% Bi₂Te₃+5% Bi₂Se₃ doped with CuBr were prepared by hot pressing method assited A. C current. Property variations of materials were investigated as a function of variables, such as hot pressing time and powder size. By this method, it is possible to minimize the defects arising from the vaporization of Te due to the very short processing time. At the conditions of hot pressing at 400℃ for 2 min. under 150Kgf/㎠, and the particle size of 70 to 125㎛ range of powder, the maximum Z value (figure of merit) was 2.2 x 10^(-3)K^(-1).

Nutritional intake of Korean population before and after adjusting for within-individual variations

Dong Woo Kim,Jae Eun Shim,Hee Young Paik,Won O Song,Hyojee Joung 한국영양학회 2011 Nutrition Research and Practice Vol.5 No.3

Accurate assessment of nutrient adequacy of a population should be based on usual intake distribution of that population. This study was conducted to adjust usual nutrient intake distributions of a single 24-hour recall in 2001 Korean National Health and Nutrition Surveys (KNHNS) in order to determine the magnitude of limitations inherent to a single 24-hour recall in assessing nutrient intakes of a population. Of 9,960 individuals who provided one 24-hour recall in 2001 KNHNS, 3,976 subjects provided an additional one-day 24-hour recall in 2002 Korean National Nutrition Survey by Season (KNNSS). To adjust for usual intake distribution, we estimated within-individual variations derived from 2001 KNHNS and 2002 KNNSS using the Iowa State University method. Nutritionally at risk population was assessed in reference to the Dietary Reference Intakes for Koreans (KDRIs). The Korean Estimated Average Requirement (Korean EAR) cut-point was applied to estimate the prevalence of inadequate nutrient intakes except for iron intakes, which were assessed using the probability approach. The estimated proportions below Korean EAR for calcium, riboflavin, and iron were 73%, 41%, and 24% from usual intake distribution and 70%, 51%, and 39% from one-day intake distribution, respectively. The estimated proportion of sodium intakes over the Intake Goal of 2,000 mg/day was 100% of the population after adjustment. The energy proportion from protein was within Korean Acceptable Macronutrient Distribution Ranges (Korean AMDR), whereas that of carbohydrate was higher than the upper limit and that of fat was below the lower limit in the subjects aged 30 years or older. According to these results, the prevalence of nutritional inadequacy and excess intake is over-estimated in Korea unless usual intake distributions are adjusted for one-day intakes of most nutrients.

Sedimentological Characteristics along Yongdong Fault Zone in Cretaceous Yongdong Basin, Korea

Dong-Won Lee(이동우),Kwang-Ho Paik(백광호) 대한지질학회 1989 지질학회지 Vol.25 No.3