차량용 터보차저 서지현상에 대한 실험적 연구

이형창(Hyung Chang Lee),한재영(Jae Young Han),임석연(Seok Yeon Im),유상석(Sang Seok Yu) 대한기계학회 2014 대한기계학회 춘추학술대회 Vol.2014 No.5-2

임상연구 : 심폐체외순환후 Protamine의 대동맥 주입과 중심정맥 주입간의 혈역학적 비교

이형창 ( Hyung Chang Lee ),진영준 ( Young Jhoon Chin ),정찬종 ( Chan Jong Chung ),최소론 ( So Ron Choi ) 대한마취과학회 2007 Korean Journal of Anesthesiology Vol.53 No.3

1998, 1999년도 우리나라에서 시행된 근치적 유방 전절제술 후 방사선치료 현황 조사

금기창(Ki Chang Keum),심수정(Su Jung Shim),이익재(Ik Jae Lee),박원(Won Park),이상욱(Sang-wook Lee),신현수(Hyun Soo Shin),정은지(Eun Ji Chung),지의규(Eui Kyu Chie),김일한(Il Han Kim),오도훈(Do Hoon Oh),하성환(Sung Whan Ha),이형식(Hyung 대한방사선종양학회 2007 Radiation Oncology Journal Vol.25 No.1

목 적: 유방암에 대한 방사선치료의 적정성과 안전성을 보장하고 궁극적으로 치료효과를 향상시키기 위한 방사선 치료 기술 표준화를 위하여 우리나라 전국 병원을 대상으로 하는 치료형태 조사연구(patterns of care study, PCS) 를 계획하였다. 그 두 번째 단계로 근치적 유방 전절제술 후 시행한 방사선치료 방법에 대하여 조사하고 분석하였다. 대상 및 방법: 조사하고자 하는 입력 문항을 개발하였고 동시에 인터넷을 통하여 조사자가 직접 입력할 수 있도 록 Web 기반 입력 프로그램(www.pcs.re.kr)을 개발하였다. 대상 환자들은 1998년도에 근치적 유방 전절제술 후 방 사선치료를 받은 환자로 전수 조사를 하지 않고 임의 추출하여 조사하였다. 입력 문항은 149개로 병력과 이학적 소견, 수술 소견과 병리소견, 항암화학요법, 호르몬요법, 방사선치료계획, 방사선치료, 치료 중 부작용, 치료 효과, 합병증 등 9군으로 나누어져 있다. 17개 병원에서 입력된 286명의 데이터를 분석하였다. 결 과: 연령은 20∼81세(중앙값 44세)였다. 환자의 병기는 AJCC (American Joint Committee on Cancer) 6판에 따라 분류하였으며 T1: 9.7%, T2: 59.2%, T3: 25.6%, T4: 5.2%이었으며 T0가 1예 있었다. 액와림프절 곽청술에서 떼어낸 림프절이 10개 미만인 환자가 10.5%, 10개 이상인 환자가 86.7%이었으며 7.3% 환자에서 림프절 전이가 없었고, 림프절 전이가 3개 이하인 경우가 14%, 4∼9개가 38.8%, 10개 이상 전이된 경우가 38.5%였다. 따라서 병기 I기: 0.7%,IIa기: 3.8%, IIb기: 9.8%, IIIa기: 43.0%, IIIb기: 2.8%, IIIc기: 38.5%이었다. 방사선치료가 시행된 시기에 따라서는 수술후에 항암약물치료를 마치고 방사선치료를 한 경우가 47.9%로 가장 많았고, 수술 후 약물치료를 시행하고 방사선 치료를 시행한 후에 다시 약물치료를 시행한 경우가 35.0%로 그 다음으로 많았다. 수술 전 약물치료를 시행하고 그 후에 방사선치료를 시행한 경우도 12.5%였다. 방사선치료 범위는 전체의 5.6%가 흉벽만 치료받았고 20.3%는 흉벽과 쇄골상 림프절을, 27.6%는 흉벽과 쇄골상 림프절과 내유방림프절을, 25.9%에서는 흉벽과 쇄골상 림프절을 치료하면서 액와 후방조사를, 19.9%에서는 흉벽과 쇄골상 림프절과 내유방림프절을 치료하면서 액와 후방조사를 시행하였다. 2예(0.7%)에서는 내유방림프절만 치료하였다. 흉벽의 방사선치료 방법에 있어서는 57.3%에서 양쪽 접선조사를 사용하였고, 42%에서는 전자선으로 치료하였다. 양쪽 접선조사를 시행한 경우에는 54.8%에서 조직보상체를 사용하였고, 전자선으로 치료한 경우는 52.5%에서 사용하였으며 흉벽에 조사된 방사선량은 91.3%에서 45∼50.4 Gy이었으며, 5.9%에서 그 이상이 2.8%에서 그 미만이 조사되었다. 쇄골상 림프절에 조사된 방사선량은 89.5% 에서 45∼50.4 Gy이었으며, 2.4%에서 그 이상이 8%에서 그 미만이 조사되었다. 결 론: 유방 보존술 후 방사선치료와는 달리 근치적 유방 전절제술 후 방사선치료는 다양한 형태로 시행되고 있음을 알 수 있었다. 향후 치료방법에 따른 치료성적을 분석함으로써 적절한 방사선 치료 방법을 제시할 수 있을 것이다. P urpose: To determine the patterns of evaluation and treatment in patients with breast cancer after mastectomy and treated with radiotherapy. A nationwide study was performed with the goal of improving radiotherapy treatment. Materials and Methods: A web- based database system for the Korean Patterns of Care Study (PCS) for 6 common cancers was developed. Randomly selected records of 286 eligible patients treated between 1998 and 1999 from 17 hospitals were reviewed. R esults: The ages of the study patients ranged from 20 to 80 years (median age 44 years). The pathologic T stage by the AJCC was T1 in 9.7% of the cases, T2 in 59.2% of the cases, T3 in 25.6% of the cases, and T4 in 5.3% of the cases. For analysis of nodal involvement, N0 was 7.3%, N1 was 14%, N2 was 38.8%, and N3 was 38.5% of the cases. The AJCC stage was stage I in 0.7% of the cases, stage IIa in 3.8% of the cases, stage IIb in 9.8% of the cases, stage IIIa in 43% of the cases, stage IIIb in 2.8% of the cases, and IIIc in 38.5% of the cases. There were various sequences of chemotherapy and radiotherapy after mastectomy. Mastectomy and chemotherapy followed by radiotherapy was the most commonly performed sequence in 47% of the cases. Mastectomy, chemotherapy, and radiotherapy followed by additional chemotherapy was performed in 35% of the cases, and neoadjuvant chemoradiotherapy was performed in 12.5% of the cases. The radiotherapy volume was chest wall only in 5.6% of the cases. The volume was chest wall and supraclavicular fossa (SCL) in 20.3% of the cases; chest wall, SCL and internal mammary lymph node (IMN) in 27.6% of the cases; chest wall, SCL and posterior axillary lymph node in 25.9% of the cases; chest wall, SCL, IMN, and posterior axillary lymph node in 19.9% of the cases. Two patients received IMN only. The method of chest wall irradiation was tangential field in 57.3% of the cases and electron beam in 42% of the cases. A bolus for the chest wall was used in 54.8% of the tangential field cases and 52.5% of the electron beam cases. The radiation dose to the chest wall was 45∼59.4 Gy (median 50.4 Gy), to the SCL was 45∼59.4 Gy (median 50.4 Gy), and to the PAB was 4.8∼38.8 Gy, (median 9 Gy) Conclusion: Different and various treatment methods were used for radiotherapy of the breast cancer patients after mastectomy in each hospital. Most of treatment methods varied in the irradiation of the chest wall. A separate analysis for the details of radiotherapy planning also needs to be followed and the outcome of treatment is needed in order to evaluate the different processes.

가변체류시간을 이용한 정수장 유입 탁도 예측기법 개발

이호현(Lee Ho Hyun),류승훈(Ryu Seung Hun),김정훈(Kim Jung Hun),이형창(Lee Hyung Chang),홍성택(Hong Sung Taek) 한국통신학회 2019 한국통신학회 학술대회논문집 Vol.2019 No.6

실험연구 : 말초신경손상 쥐에서 중추신경계 α2-아드레날린성 수용체 아형의 발현

최소론 ( So Ron Choi ),이형창 ( Hyung Chang Lee ),정찬종 ( Chan Jong Chung ),김해규 ( Hae Kyu Kim ) 대한마취과학회 2006 Korean Journal of Anesthesiology Vol.51 No.4

Background: The change of expression of the α2-adrenergic receptor (α2-AR) subtypes in the thalamus and hypothalamus were investigated in a neuropathic pain rat model. Methods: The left sciatic nerve was clamped for creating a neuropathic pain model in five rats. A sham operation was done in three rats as control group. Behavioral tests for pain were conducted by using mechanical stimuli applied to the hind paws. After 7 days, the expression of α2-AR subtype mRNA in the rat thalamus and hypothalamus was measured using real time polymerase chain reaction. Results: Mechanical allodynia were developed on postoperative 1, 3, and 7 days in the neuropathic pain model. The expression of α2A-AR, α2B-AR, and α2C-AR was significantly higher in the thalamus and hypothalamus in the neuropathic pain model (P > 0.05). Conclusions: These results would suggest that the subtypes of α2-AR in thalamus and hypothalamus may contribute to produce neuropathic pain. (Korean J Anesthesiol 2006; 51: 468~75)

임상연구 : 소아 사시수술 시 Remifentanil 마취의 혈역학적 반응과 회복 특징

정찬종 ( Chan Jong Chung ),김태균 ( Tae Gyun Kim ),이형창 ( Hyung Chang Lee ),이승철 ( Seung Cheol Lee ),진영준 ( Young Jhoon Chin ) 대한마취과학회 2006 Korean Journal of Anesthesiology Vol.51 No.2

Background: This study evaluated the hemodynamic response and recovery profile of remifentanil-N2O anesthesia, compared with secoflurane-N2O anesthesia in pediatric surgery. Methods: Fifty-seven healthy children aged 1-9 years undergoing strabismus surgery were randomly assigned to two groups, group R or group S. None of the children was premedicated with an anticholinergic agent. Anesthesia was induced with intravenous ketamine 1.0 mg/kg. A laryngeal mask airway (LMA) was placed with rocuronium 0.4 mg/kg. Anesthesia was maintained with sevoflurane 2.0-3.0 vol% and N2O 66% in group S, and with remifentanil 0.75㎍/kg over 1 min followed by remifentanil 0.5㎍/kg/min and N2O 66% in group R. At the end of surgery, the anesthetic agents were discontinued, and the early emergence, recovery, and side effects were assessed. Results: During anesthesia, the heart rate and blood pressure were lower in group R (P < 0.05). The incidence of an oculocardiac reflex was similar in both groups. The times to spontaneous ventilation and the removal of LMA were similar in the two groups. The times from eye opening to command, orientation and full recovery were faster in group R (P < 0.05). The incidence of postoperative nausea and vomiting was similar in both groups. The incidence of coughing was lower in group R (P < 0.05). Mild pruritus developed in 17.2% of patients in group R. Conclusions: In pediatric strabismus surgery, remifentanil provided similar hemodynamic stability, and an earlier and smoother recovery, compared with sevoflurane anesthesia. (Korean J Anesthesiol 2006; 51: 174~8)

레이저 융합된 Co-Cr 합금의 물리적 성질에 관한 연구

배기창,우이형,이성복,Bae Ki-Chang,Woo Yi-Hyung,Lee Sung-Bok 대한치과보철학회 2003 대한치과보철학회지 Vol.41 No.4

Statement of problem : The joints of removable partial denture alloys have failed frequently after routine usage. Purpose : The purpose of this study was to evaluate the mechanical properties of the laser welded Co-Cr alloys. Material and method : For this study 20 Co-Cr specimens were casted and 10 of them were seperated on the middle area and laser welded with Alpha laser welding machine(Siro Lasertec, Pforzheim, Germany). Rest of them which were as cast, were used as a control group. For the section of the experimental specimens, wire cutting machine was used to make a even gap of the all specimens. Laser welding was done with manufacturer's instrunction and tested each specimen by Instron Machine. Tensile strength, 0.2% yield strength and % elongations were recorded. Fractured surfaces were investigated with SEM. Results : The results were as follows : 1. The tensile strength of the laser welded group(617.7MPa) was about 75% of the as cast group(820.4MPa). It had stastically significant differences(p<0.05). 2. The % elongation of the experimental group was 6.6 which was lower than the control group(14.3). 3. Fracture of the experimental group occured in the welded surface and showed many voids. In contrast, the fracture surface of the control group was showed rough surfaces without any voids. Conclusion : The tensile strengths of the as-cast joints were higher than those for the laser welded joints, and the % elongation of the experimental group was lower than the control group. Porosity was found in laser-welded joints.