9-12%Cr강의 첨가원소 및 열처리에 따른 미세조직거동과 경도변화

주성욱,유정훈,신기삼,허성강,이재현,석진익,김병훈,김정태 국립7개대학공동논문집간행위원회 2004 공업기술연구 Vol.4 No.-

9-12%Cr steel are getting increasing attention for expanded application as high temperature materials applicable for gas turbine compressors, steam turbine rotors, blade and casing. For efficient and extensive application of 9-12%Cr steel, the data in addition to the improvement of mechanical properties on the correlation of microstructural evolution and mechanical properties are inevitable and thus the investigation in this study is performed for the determination for the specimens heat-treated at 600, 650 and 700℃ for 1000, 3000 and 5000hrs. The microstructure of as-received specimen was tempered martensite, with a high dislocation density and secondary phases. Upon high temperature heat-treatment, the martensite lath got larger and dislocation density decreased resulting the reduction of the strength. In addition, sharp growth of secondary phases was observed in the specimen heat-treated at 700℃ for 5000hrs. A specimen aged at 600℃ and 650℃ Laves phase was observed. The hardness showed close relationship with the secondary phase particle and dislocation density.

발열을 동반한 호중구감소증에서 Cefepime 단독투여와 Ceftazidime 및 Tobramycin 병합투여의 효능비교

정현욱,채제욱,강미라,양정채,문치숙,기현균,장현하,오원섭,김기현,백경란,이남용,송재훈 대한감염학회 2004 감염과 화학요법 Vol.36 No.6

목적 : 국내에서 발열을 동반한 호중구감소증이 있는 악성 종양환자에게 경험적 항생제로 베타락탐계 항생제와 아미노배당체의 병합요법의 사용이 일반적이다. Cefepime은 광범위 항균 작용을 가지고 있어, 그람 음성균 뿐만 아니라 그람 양성균에 대해서도 우수한 효과를 나타낸다. 재료 및 방법: 발열을 동반한 호중구감소증이 있는 악성 종양환자를 대상으로 무작위, 공개, 비교 연구를 시행하였다. 대상 환자를 무작위로 cefepime 단독요법군과 ceftazidime 및 tobramycin 병합요법군으로 나누어 투여하고 각각의 임상적 효능과 안전성을 비교하였다. 구강및 인후 점막염이 있는 환자에서 분리된 녹색 연쇄알 구균에 대한 항생제 내성 정도를 조사하였다. 결과 : 대상환자 89명 중 CA 투여군이 48예(53.9%), CT 투여군이 41예(46.1%)이었다. 발열의 유형별로 MDI는 18예(20.2%), CDI는 9예(10.1%), UF는 62예(69.7%)로 두 군 간에 차이가 없었다. CA 투여군과 CT 투여군의 임상적 호전률은 시험약 투여 후 2-4일째 각각 91.7%, 85.4% (P=0.31), 치료 종료 시 각각 91.7%, 100% (P=0.15)로 두 군간에 유의한 차이가 없었다. 치료 종료 시 CA 투여군과 CT 투여군의 세균학적 소실률은 모두 100%로 두 군간의 유의한 차이가 없었다(P=0.78). 점막염이 있는 환자로부터 녹색 연쇄알 구균이 분리된 경우는 25예(28.1%)이었으며, 분리된 녹색 연쇄알 구균은 penicillin, ceftriaxone, cefepime, vancomycin에 모두 감수성을 보였다. 약제 관련 이상 반응의 발생 빈도도 두 군간에 유의한 차이가 없었다. 결론 : 발열을 동반한 호중구감소증이 있는 악성 종양환자의 경험적 항생제로서 cefepime 단독요법은 ceftazidime 및 아미노배당체의 병합요법만큼 효과적이고 안전하였다. Background : Broad-spectrum antibiotic therapy has been recommended as an empirical regimen in cancer patients with febrile neutropenia. Cefepime is a fourth generation cephalosporin with good activity against both gram-positive cocci and gram-negative bacilli. Materials and Methods : To compare the efficacy and safety of cefepime alone with ceftazidime plus tobramycin as empirical regimen for adult cancer patients with febrile neutropenia, a randomized, open label, comparative trial was performed. If the patient showed clinical improvent 72 hours, antibiotic could be changed to oral ciprofloxacin. Clinical and microbiological responses were determined at 72 hours and at the end of therapy. To investigate the antimicrobial resistance of viridans streptococci, swab cultures were obtained from throat in all enrolled patients and antimicrobial susceptibility tests were performed by using microdilution method according to the NCCLS. Results : A total of 89 patients were enrolled. Forty-eight patients received cefepime alone (CA), and 41 patients received ceftazidime plus tobramycin (CT). Demographic and baseline clinical characteristics were similar in both groups (P>0.05). The initial clinical success rate at day 2-4 in group CA (91.7%) was similar with that in CT group (85.4%) (P=0.31). At the end of therapy, the final clinical success rate in CA group (91.7%) was similar to that in CT group (100%) (P=0.15). In 18 patients, with microbiologically defined infections, the eradication rate was 100% in both groups. Adverse events including liver dysfunction (21.3%) and renal dysfunction (2.2%), were similar in both groups (P=0.87). Viridans streptococci were isolated from the throat cultures in 25 cases, and all of these strains were susceptible to penicillin (MIC_(90) 0.12 ㎍/mL), cefepime (1 ㎍/mL), and vancomycin (0.12 ㎍/mL). Conclusion : Efficacy and safety of cefepime monotherapy was comparable to the combination of ceftazidime and tobramycin. It could be used as an alternative empirical regimen for treating cancer patients with febrile neutropenia.

항정신병약물을 처음으로 사용하는 초발 정신증 환자에서 나타나는 체중 및 대사성 지표의 변화 : 후향적 연구

김우진,심주철,공보금,강제욱,문정준,김정은,김민걸,박민경,김성진,김현정,정도운 대한생물치료정신의학회 2011 생물치료정신의학 Vol.17 No.2

Objectives:This study was to identify weight & metabolic changes in first-episode psychotic patients with antipsychotics use and investigate the differences of weight & metabolic changes between first-episode psychotic patients and controls with antipsychotics use. Method:In this retrospective study, twenty eight first-episode psychotic patients and twenty eight controls with schizophrenia, schizoaffective or bipolar disorder defined by DSM-IV criteria were included. Information about demographic and clinical characteristics of the subjects was gathered from the medical records. Also body weight, sBP, dBP, fasting glucose, lipid profile and WBC count were evaluated before and after antipsychotics use. Rogistic regression was conducted to assess factors associated with weight gain. Results:First-episode psychotic patients showed more weight and BMI changes than controls after antipsychotics use, and these changes continue over 12 months. On the other hand, there were no significant factors associated with weight gain. Conclusion:The results of present study suggest that antispychotics is one of the major causes inducing weight gain of psychotic patients and antipsychotics-induced weight gain is more vulnerable to drug-naive first-episode psychotic patients.

Effect of DA-9701 on the Normal Motility and Clonidine-induced Hypomotility of the Gastric Antrum in Rats

( Je Wook Kang ),( Dae Kyeong Han ),( Ock Nyun Kim ),( Kwang Jae Lee ) 대한소화기기능성질환·운동학회 2016 Journal of Neurogastroenterology and Motility (JNM Vol.22 No.2

Background/Aims DA-9701 is a novel prokinetic agent. In the present study, we investigated the effect of DA-9701 on the motility of the gastric antrum in the normal and clonidine-induced hypomotility in an in vivo animal model. Methods A strain gauge force transducer was sutured on the gastric antrum to measure the contractile activity in rats. A total of 28 rats were subclassified into the 4 groups: (1) the placebo group, (2) the DA-9701 group, (3) the placebo group in the clonidine-pretreated rats, and (4) the DA-9701 group in the clonidine-pretreated rats. After the basal recording, either placebo (3% [w/v] hydroxypropylmethyl cellulose) or DA-9701 was administered. Contractile signals were measured after the administration and after a meal. In the clonidinepretreated rats, either placebo or DA-9701 was administered. Contractile signals were measured after the administration and after a meal. Results Oral administration of DA-9701 did not significantly alter the motility index of the gastric antrum in the preprandial and postprandial periods, compared with the placebo group. The administration of clonidine decreased the motility index of the gastric antrum in the preprandial and postprandial periods, compared with the administration of placebo. This reduction of the antral motility by the administration of clonidine was not observed in the clonidine-pretreated DA-9701 group. The percentage of the motility index in the postprandial period was significantly greater in the clonidine-pretreated DA-9701 group, compared with the clonidine-pretreated placebo group. Conclusions DA-9701 improves the hypomotility of the gastric antrum induced by clonidine, suggesting its gastroprokinetic effect in the pathologic condition. (J Neurogastroenterol Motil 2016;22:304-309)

청소년의 스마트폰 사용시간과 우울증상 및 자살의 관계

강제욱(Je-Wook Kang) 대한사회정신의학회 2019 사회정신의학 Vol.24 No.2

연구목적 : 본 연구에서는 스마트폰 과의존이 청소년기의 우울감과 자살사고에 미치는 영향을 알아보고자 하였다. 방 법 : 2017년에 실시한 제 13차 청소년 건강행태 온라인조사의 원시자료를 사용하여 54,603명의 자료를 최종 분석하였다. 사회인구학적 정보와 정신사회적 요인을 평가하기 위해 우울감, 자살생각과 계획, 시도 등을 주요 변수로 사용하였다. 그리고 스마트폰 사용 시간을 주중과 주말로 나누어 각각의 특성을 분석하였다. 결 과 : 주중 스마트폰 사용시간이 300분이상인 청소년은 14.4%, 주말 스마트폰 사용시간이 480분 이상인 청소년의 비중이 18.2%로 나타 났다. 또한 주중 300분 이상 스마트폰을 사용하는 청소년의 경우 60분 이하로 사용하는 집단보다 우울증상의 위험성이 1.56배(OR= 1.56 ; 95% CI, 1.43~1.71 ; p<0.01) 높게 나타났으며, 자살사고도 유의하게 높아지는 것으로 나타났다(OR=1.23 ; 95% CI, 1.08~ 1.39 ; p<0.01). 주말 스마트폰 사용의 경우 480분 이상 스마트폰을 사용하는 경우, 우울증상의 위험성이 1.41배 증가하였고(OR= 1.41 ; 95% CI, 1.30~1.53 ; p<0.01), 자살사고도 유의하게 증가하는 것으로 나타났다(OR=1.16 ; 95% CI, 1.03~1.31 ; p=0.02). 반면 주중 평균 120~180분 사용하는 청소년의 경우에는 자살계획의 위험성이 감소하였으며(OR=0.84 ; 95% CI, 0.70~1.00 ; p=0.05), 주말 평균 240~300분 사용하는 경우에도 자살 사고의 위험성이 낮아지는 결과를 보였다(OR=0.87 ; 95% CI, 0.78~0.98 ; p=0.02). 결 론 : 본 연구의 결과를 토대로 살펴 볼 때 스마트폰 사용은 청소년기의 우울감과 자살사고에 긍정적, 부정적인 영향을 미치는 것으로 나타났다. 이러한 결과를 통해서 적절한 청소년기의 스마트폰 사용시간에 대한 합리적인 가이드라인을 세우는 데 도움이 될 것으로 생각된다. Objectives : The purpose of this study was to investigate the effects of smartphone dependence on adolescent depression and suicide. Methods : Data from 54,603 people were finally analyzed using raw data from ‘the 13th Korea Youth Risk Behavior Web-based Survey (KYRBWS)’ conducted in 2017. In order to evaluate psychosocial factors, depression, suicidal idea, planning and attempts were used as the main variables. The characteristics of each smartphone were analyzed by dividing smart-phone usage time into weekdays and weekends. Results : Adolescents who used smartphones for 300 minutes or more during the week showed 1.56 times higher risk of depression (OR=1.56 ; 95% CI, 1.43-1.71 ; p<0.01) than those who used less than 60 minutes. Incidents of suicide idea were also significantly higher (OR=1.23 ; 95% CI, 1.08-1.39 ; p<0.01). In the case of weekend smartphone use, the risk of depression increased by 1.41 times (OR=1.41 ; 95% CI, 1.30-1.53 ; p<0.01). Incidents of suicide idea were also significantly higher (OR=1.16 ; 95% CI, 1.03-1.31 ; p=0.02). On the other hand, adolescents who used 120-180 minutes on weekdays, had a lower risk of suicide planning (OR=0.84 ; 95% CI, 0.70-1.00 ; p=0.05). Also, risk of suicide idea was also lower when using the weekend for 240-300 minutes (OR=0.87 ; 95% CI, 0.78-0.98 ; p=0.02). Conclusion : This study provide mixed results between smartphone use time and mental health problem. This findings can offer better understanding and providing guideline to adolescent with using smartphone.

주의력결핍 과잉행동장애에서 파탄적 행동장애의 공존과 약물치료

강제욱(Je Wook Kang),박은진(Eun Jin Park),김성찬(Seong Chan Kim),신의진(Yee-Jin Shin),신윤미(Yun-Mi Shin),정재석(Jaesuk Jung),천근아(Keun-Ah Cheon),육기환(Ki-Hwan Yook) 대한소아청소년정신의학회 2012 소아청소년정신의학 Vol.23 No.S

Disruptive behavioral disorders [oppositional defiant disorder (ODD) and conduct disorder (CD)] are common comorbid disorders in children and adolescents with attention-deficit/hyperactivity disorder (ADHD). ODD/CD may be comorbid up to 60% of children and adolescents with ADHD. Comorbid ODD and CD symptoms can have a significant impact on the course and prognosis o f patients with ADHD. Stimulant medications have shown effectiveness in treating both core ADHD symptoms and oppositional symptoms. Assessment and management of comorbid disruptive behavioral symptoms is an essential part in evaluation and treatment of ADHD patients. Further research is needed to investigate the efficacy and safety of various behavioral and medication regimens for ADHD, comorbid ODD and CD and to examine the relationships between ADHD, comorbid ODD and CD.

One-Chip Microcontroller에 의한 Switched Reluctance Motor의 속도제어에 관한 연구

강욱,김학성,류홍제,원충연 成均館大學校 科學技術硏究所 1993 論文集 Vol.44 No.2

The switched reluctance motor(SRM) drive is becoming an attractive candidate for replacing conventional adjustable speed ac and do drive in many industrial and consumer application like pumps, fans, household appliances and automotive actuator etc. The control method of triggering and conduction angle for variable speed drive is presented in this paper. It also describes new work in the area of electronic control of SRM. The control functions and converter switching signals are processed in low cost microcontroller. Experimental verification is provided for 8/6 pole prototype SRM drive.

Endometrial Stromal Sarcoma Presented as an Incidental Lung Mass with Multiple Pulmonary Nodules

Kang, Dong Oh,Choi, Sue In,Oh, Jee Youn,Sim, Jae Kyeom,Choi, Jong Hyun,Choo, Ji Yung,Hwang, Jin Wook,Lee, Seung Heon,Lee, Ju-Han,Lee, Ki Yeol,Shin, Chol,Kim, Je Hyeong The Korean Academy of Tuberculosis and Respiratory 2014 Tuberculosis and Respiratory Diseases Vol.76 No.3

Low-grade endometrial stromal sarcoma (ESS) is an uncommon gynecologic malignancy of mesodermal origin. Pulmonary metastasis of low-grade ESS can occur years and decades after the treatment of the primary disease. Low-grade ESS is frequently mistaken as benign uterine neoplasm like uterine leiomyoma, which can potentially lead to a misdiagnosis. We present a case of a 42-year-old woman with low-grade ESS, that initially presented as an incidental lung mass with multiple pulmonary nodules, seven years after an uterine myomectomy. A $6.9{\times}5.8cm-sized$ intrapelvic mass suspected of uterine origin was discovered while searching for potential extrathoracic primary origin. A pelviscopy and simultaneous thoracoscopic lung biopsy were conducted for pathologic diagnosis. Finally, the diagnosis was confirmed as low-grade ESS with lung metastasis based on the histopathologic examination with immunohistochemical stain, which was showed positive for CD10 and hormone receptor markers (estrogen and progesterone receptors) in both pelvic and lung specimens.

High prevalence of hepatitis B and hepatitis C virus infections in Korean patients with hematopoietic malignancies

Kang, Jun,Cho, Jeong Hyun,Suh, Cheol Won,Lee, Dae Ho,Oh, Heung Bum,Sohn, Yong Hak,Chi, Hyun Sook,Park, Chan Jeong,Jang, Sung Soo,Lee, Kyoo Hyung,Lee, Je-Hwan,Lee, Jung Hee,Lee, Sang Wook,Chung, Young Springer-Verlag 2011 Annals of hematology Vol.90 No.2

만성 B형 간염과 간경변 환자에서 Lamivudine 저항성 B형 간염 바이러스의 출현양상 및 YMDD motif 돌연변이 검출

강성호,박태욱,박영민,정규원,안병민,배시현,김부성,박두호,이창돈,변병훈,최종영,신제현,차상복,선희석 대한간학회 2001 Clinical and Molecular Hepatology(대한간학회지) Vol.7 No.1

Background/Aims: Lamivudine is an antiviral nucleoside analogue effective for the treatment of hepatitis B virus (HBV) infection via the inhibition of DNA polymerase activity. The mutations, however, in YMDD motif, such as YVDD and YIDD, have been found to interfere with the therapeutic efficacy of lamivudine. This study was performed to identify the role of such mutant-type HBV among Korean hepatitis B patients with chronic hepatitis or cirrhosis receiving lamivudine treatment. Methods: Serum samples were collected from four groups of patients; patients with breakthrough (group I, n = 8); patients who showed no response after the treatment (group II, n = 6); patients who showed good response (group III, n = 6); patients with chronic hepatitis B without any treatment (group IV, n = 4). Mutations were detected by PCR-cloning and automated sequencing. Results: Mutations in YMDD were found in only 4 (50%) in group I and were negative in group II. No mutations could be identified in the serum samples collected before treatment and from groups III and IV. YVDD mutation was found to be associated with two additional mutations, 'L-to-M' in 528th amino acid and 'L-to-V' in 577th amino acid. Conclusions: Lamivudine resistance appeared in three different patterns: (1) breakthrough related to the mutations in YMDD motif; (2) breakthrough not related to the YMDD mutations; and (3) primary non-responder not related to the YMDD mutations.(Korean J Hepatol 2001;7:15-33)