• Title/Summary/Keyword: 이종세

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Usefulness of Cardiac Troponin I as a Prognostic Marker in Noncardiac Critically Ill Patients (비순환기계 중환자의 예후인자로서 Cardiac Troponin I의 유용성)

  • Kim, Hwi Jong;Ham, Hyoun Seok;Cho, Yu Ji;Kim, Ho Cheol;Lee, Jong Deok;Hwang, Young Sil
    • Tuberculosis and Respiratory Diseases
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    • v.59 no.1
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    • pp.53-61
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    • 2005
  • Background : Cardiac troponin I (cTnI) is a specific marker of myocardial injury. It is known that a higher level of cTnI is associated with a poor clinical outcome in patients with acute coronary syndrome. An elevation in cTnI is also observed in various noncardiac critical illnesses. This study evaluated whether cTnI is useful for predicting the prognosis in noncardiac critically ill patients. Methods : From June 2003 to July 2004 at Gyeongsang National University Hospital, we enrolled 215 patients (male:142, female:73, mean age:$63{\pm}15$ years ) who were admitted for critical illness other than acute coronary syndrome at the medical intensive care unit(ICU). The severity score of critical illness (SAPS II and SOFA) was determined and serum cTnI level was measured within 24 hours after admission to the ICU. The mortality rate was compared between the cTnI-positive (${\geq}0.1{\mu}g/L$) and cTnI-negative ($cTnI<0.1{\mu}g/L$) patients at the $10^{th}$ and $30^{th}$ day after admission to the ICU. The mean cTnI value was compared between the survivors and non-survivors at the $10^{th}$ and $30^{th}$ day after admission to the ICU in the cTnI-positive patients. The correlation between cTnI and the severity of the critical illness score (SAPS II and SOFA) was also analyzed in cTnI-positive patients. Results : 1) The number of cTnI-negative and positive patients were 95(44%) and 120(56%), respectively. 2) The mortality rate at the $10^{th}$ and $30^{th}$ day after admission to the ICU was significantly higher in the cTnI-positive patients (29%, 41%) than in the cTnI-negative patients (12%, 21%)(p<0.01). 3) In the cTnI-positive patients, the mean value of the cTnI at the $10^{th}$ and $30^{th}$ day after admission to the ICU was significantly higher in the non-survivors ($4.5{\pm}9.2{\mu}g/L$, $3.5{\pm}7.9{\mu}g/L$) than in the survivors($1.8{\pm}3.6{\mu}g/L$, $2.0{\pm}3.9{\mu}g/L$) (p < 0.05). 4) In the cTnI-positive patients, the cTnI level was significantly correlated with the SAPS II score (r=0.24, p<0.001) and SOFA score (r=0.30, p<0.001). Conclusion : The cTnI may be a useful prognostic marker in noncardiac critically ill patients.

Genetic Divergence and Phylogenetic Relationships among the Korean Fireflies, Hotaria papariensis, Luciola lateratis, and Pyrocoelia rufa(Coleoptera: Lampyridae), using Mitochondrial DNA Sequences (미토콘드리아 DNA의 염기서열을 이용한 파파리반딧불이, 애반딧불이 및 늦반딧불이 (딱정벌레목: 반딧불이과)의 유전적 분화 및 계통적 관련)

  • 김익수;이상철;배진식;진병래;김삼은;김종길;윤형주;양성렬;임수호
    • Korean journal of applied entomology
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    • v.39 no.4
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    • pp.211-226
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    • 2000
  • Genetic divergence and phylogenetic relationships among the major Korean fireflies (Hotaria papariensis, Luciola lateralis, and Pyrocoelia rufa) were studied. A portion of mitochondrial COI (403 bp) and 165 rRNA (490~504 bp) genes were sequenced, and the GenBank-registered, homologous 165 rRNA sequences of Japanese fireflies were compared (27 species of Lampyridae, one of Lycidae, and one of Rhgophthalmidae). Greatest DNA and/or amino acid sequence divergence was found when P rufa, belonging to Lampyrinae was compared with H. papariensis and L. lateralis, both belong-ing to Luciolinae, confirming the current taxonomic status of the species. In the PAUP and PHYLIP analyses with 165 rRNA data, grouping of the two geographic samples of H. papariensis with H. tsushimana validate the use of generic name, Hotaria. Nevertheless, lack of sister-group relationship of the two geographic samples of H. papariensis renders further investigation on this group . Although the Korean and Japanese L. lateralis formed a strong monophyletic group, a substantial genetic differentiation was detected between them (2.9% of 165 rRNA gene sequence divergence). Finally, the geographic samples of Korean p. rufa strongly formed a group with Japanese p. rufa, warranting the use of generic name, Pyrocoelia, but the genetic distance observed between the Cheju-Island individual and all others requires further investigation on this subject. Summarized, this study supports the current taxonomic status of the Korean fireflies in that each respectively formed a strong monophyletic group with its own species or genus.

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Surgical Treatment of Gastric Cancer Invading the Pancreatic Head or Duodenum (췌장 두부 또는 십이지장을 침범한 위암에서의 수술적 치료)

  • Kim, Su-Yeol;Lee, Jong-Myeong;Kim, Woo-Young
    • Journal of Gastric Cancer
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    • v.7 no.4
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    • pp.193-199
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    • 2007
  • Purpose: Combined resection of an invaded organ in advanced gastric cancer (AGC) with infiltration of adjacent organs is essential to achieve R0 resection. However, when the tumor invades the head of the pancreas or duodenum, R0 resection interferes with the lower resectability and results in a higher morbidity. Wereviewed these cases retrospectively and considered the proper extent of the surgical resection. Materials and Methods: We retrospectively analyzed cases where patients underwent surgery for gastric adenocarcinoma at the Department of Surgery, Presbyterian Medical Center, between January 1998 and December 2003. Among the 45 patients who were suspected to have pancreatic head or duodenum invasion by a primary tumor or metastatic lymph nodes based on the operative findings, we included 22 patients without incurable factors. The patients were classified into three groups: 4 patients that underwent a combined resection (PD group), 12 patients that underwent a palliative subtotal gastrectomy (STG group) and 6 patients that underwent bypass surgery only (GJ group). We analyzed the clinicopathological features, operative data and results. Results: The patients of the PD group achieved R0 resection by PD with D3 Dissection in all Patients. A pancreatic fistula was observed in one patient (morbidity 25%). There was no surgery-associated mortality (mortality 0%). All patients of the PD group were in stage IV. However, the 2-year survival rate (SR) was 75% and the 5-year SR was 50%. Six patients of the STG group underwent surgery with marginal resection and the other six patients of the STG group had a positive distal resection margin. The 2-year SR was 41.7% and the 5-year SR was 16.7%. Most of the patients of group GJ were of old age (mean age: $72.7{\pm}8.6$ years) or had chronic diseases. The 2-year SR was 0%. Conclusion: Combined resection of the pancreas and duodenum in AGC with pancreatic head invasion is relatively safe with moderate morbidity and a lower mortality. One can expect long-term survival if combined resectionis performed in cases without incurable factors.

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Comparison of Reconstructive Techniques after Total Gastrectomy as Determined by Patient Quality of Life and Nutritional Status (위전절제술 후 재건술식에 따른 환자의 영양상태와 삶의 질 비교)

  • Seo, Kyeong-Soo;Lee, Jong-Myeong;Kim, Woo-Yeong
    • Journal of Gastric Cancer
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    • v.7 no.4
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    • pp.219-227
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    • 2007
  • Purpose: Many reconstruction procedures have been developed in order to resolve patient complaints after a total gastrectomy. However, until now, there has been no general agreement with regard to the ideal reconstruction to perform after a total gastrectomy. Moreover, there have been few reports of the long-term effects of different reconstruction procedures. In this study, we compared the long-term nutritional status and quality of life for patients that received either a Roux-en-Y esophagojejunostomy (R-Y), jejunal interposition (JI), jejunal pouch interposition (JPI), or double tract reconstruction (DT), to determine the optimum reconstruction procedure after a total gastrectomy. Materials and Methods: The study consisted of 41 patients younger than 80 years who had undergone a total gastrectomy with curative resection and who had no evidence of recurrence at our hospital between August 2000 and January 2004. The patients were classified into the following four groups, according to the type of reconstruction; simple Roux-en-Y (R-Y group, n=15), jejunal interposition (JI; group, n=8), j Jejunal pouch interposition (JPI group, n=8), double tract interposition (DT group, n=10). The nutritional status was assessed by measuring body weight, serum albumin level, serum hemoglobin level, and the level of serum total protein, and the PNI (Prognostic nutritional index). Quality of life was assessed by GSRS. In addition, endoscopy was performed to confirm the presence of reflux esophagitis. Results: The laboratory findings showed no significant differences between the four groups except for a lower total protein and album level in the DT group after 3 years postoperatively (P=0.006, P=0.033). The percentage of body weight at 1 year, and 3 years postoperatively in the JI group (P=0.013, P=0.011) were significantly less than other groups (P=0.011, P=0.000). The frequency of postoperative symptoms and reflux esophagitis and eating capacity showed no significant differences between the four groups. The GSRS score in the JIP group was significantly better than for the other groups at 1 year, and 3 years postoperatively (P=0.028, P=0.003). Conclusion: We believe that the jejunal pouch interposition is the most useful of the four procedures for improving postoperative quality of life.

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Relationship between Expression of XIAP Protein in Operable Non-small Cell Lung Carcinomas and Apoptosis Index and Postoperative Prognosis (비소세포폐암조직에서 XIAP 발현과 고사지수 및 수술 후 예후와의 관계)

  • Kim, Sang Hyun;Lee, Chang Hun;Sol, Mee Young;Song, Jin Mi;Lee, Jong Hyub;Lee, Min Ki;Kim, Jong Min
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.5
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    • pp.480-489
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    • 2005
  • Background : Dysregulation of apoptosis plays an important role in carcinogenesis, tumor progression, and resistance to chemotherapy. X-linked inhibitor of apoptosis (XIAP) is considered to be the most potent caspase inhibitor of all known IAP (inhibitor of apoptosis) family members. This study was designed to assess the pattern of expression and the prognostic value of XIAP in radically resected non-small cell lung carcinoma (NSCLC) patients. Method : The expression of XIAP and its relationship with clinicopathologic parameters (patient age, TNM stage, TNM-pT, TNM-pN, histologic type, VEGF expression, microvessel density, PCNA index) and overall survival were analysed with formalin-fixed, paraffin-embedded blocks from eighty cases of NSCLC. In addition, the apoptotic index (AI) was also assessed. Results : In a regard to histologic type, squamous cell carcinoma (SCC) showed XIAP expression in 91.3%(42/46) and adenocarcinoma (AC) in 61.8%(21/34). The difference was significant(p=0.001). There was no correlation between XIAP expression and other parameters. In the group of AC, XIAP expression showed the signifcant correlation with older age group ${\geq}58years$ and VEGF expression(p=0.028, p=0.014, respectively). The AI in the group with or without XIAP expression were $2.5{\pm}4.9%$ and $18.5{\pm}28.9%$, respectively(p=0.001). Both groups just aforementioned showed no significant difference in median survival time (42.5 months, 29.8 months, respectively). Conclusion : This study suggests that the XIAP expression in NSCLCs could have relation to inhibition of apoptosis, and show differential expression according to histologic type. However, its prognostic role during the progression of NSCLC needs to be further defined.

Tuberculin Skin Test and QuantiFERON-TB Gold Assay before and after Treatment for Latent Tuberculosis Infection among Health Care Workers in Local Tertiary Hospital (일개 병원의 의료인에서 투베르쿨린 검사와 QuantiFERON-TB Gold 검사를 이용한 잠복결핵의 진단과 치료 전후의 변화)

  • Lee, Seung Jun;Kim, Hyeon Sik;Ma, Jung Eun;Lee, Sang Min;Ham, HyunSeok;Cho, Yu Ji;Jeong, Yi Yeong;Kim, Ho Cheol;Lee, Jong Deok;Kim, Sun-Joo;Hwang, Young Sil
    • Tuberculosis and Respiratory Diseases
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    • v.62 no.4
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    • pp.270-275
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    • 2007
  • The QuantiFERON-TB Gold assay and tuberculin skin test (TST) have been useful test for diagnosing latent tuberculosis infections (LTBI). However, there are few reports on the efficacy of the QuantiFERON-TB Gold assay and TST in evaluating the response after the treatment of LTBI. This study examined the changes in the TST and QuantiFERON-TB Gold assay before and after a treatment for latent tuberculosis in health care workers (HCWs) at a local tertiary hospital. Methods: A cohort of volunteers working as nurses and doctors who underwent a TST and QuantiFERON-TB Gold assay was established. The volunteers positive for the QuantiFERON-TB Gold assay had been treated with 3 months of isoniazid (INH) and rifampin (RFP). After completing treatment, the TST and QuantiFERON-TB Gold assay were repeated. Results: Of the 48 participants (14 doctors, 34 nurses, M: F=11:37, mean $age=29.9{\pm}5.5$ years, mean employment $period=74.9{\pm}64.3$ months), 19 (39.6%) tested positive to the TST (mean induration=$19.1{\pm}9.7mm$) and 8 (16.7%) were QuantiFERON-TB Gold assay. Among them, one had active pulmonary tuberculosis. Seven volunteers were consistently positive to both the TST and QuantiFERON-TB Gold assay after being medicated with INH and RFP for 3 months. Conclusion: TST and QuantiFERON-TB Gold assay are unsuitable for evaluating the treatment response of LTBI because they were consistently positive both before and after the anti-tuberculosis medication.

Prevalence and trends in obesity among Korean children and adolescents in 1997 and 2005 (한국 소아청소년의 비만 유병률 추이: 1997년과 2005년 비교)

  • Oh, Kyungwon;Jang, Myoung Jin;Lee, Na Yeoun;Moon, Jin Soo;Lee, Chong Guk;Yoo, Myung Hwan;Kim, Young Taek
    • Clinical and Experimental Pediatrics
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    • v.51 no.9
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    • pp.950-955
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    • 2008
  • Purpose : The objective of this study was to provide current estimates of the prevalence and examine trends of overweight and obesity in children and adolescents. Methods : Height and weight measurements from 183,159 (112,974 in 1997, 70,185 in 2005) children and adolescents aged 2 to 18 years were obtained via the 1997 and 2005 National Growth Survey. Obesity among children and adolescents was defined as being at or above the 95th percentile of the gender-specific body mass index (BMI) for age in the 2007 Korean National Growth Charts or a BMI of 25 or higher; overweight was defined as being at or above the 85th percentile to less than the 95th percentile BMI. Results : In 2005, 9.7% (11.3% for boys, 8.0% for girls) of South Korean children and adolescents were obese; 19.0% (19.7% for boys, 18.2% for girls) were overweight or obese. The overall prevalence of obesity increased from 5.8% in 1997 to 9.7% in 2005 (from 6.1% in 1997 to 11.3% in 2005 for boys and from 5.5% in 1997 to 8.0% in 2005 for girls); the increasing trend was most evident in boys, especially those aged 13-18 years. Conclusion : The prevalence of obesity among children and adolescents increased significantly during the eight-year period from 1997 to 2005. This study suggests that we need to make a priority of developing strategies to control obesity in children and adolescents; the potential health effects of increases in obesity are of considerable public health importance.

Preoperative Detection of Hepatic Metastases from the colorectal Cancers: Comparison of Dual-phase CT scan, Mn-DPDP enhanced MRI, and combination of CT and MRI (대장암의 간 전이 진단: 이중시기 CT, Mn-DPDP 조영증강 MRI, 그리고 CT-MRI 종합 판독의 비교)

  • Shin, Kyung-Min;Kim, Jong-Yeol;Choi, Gyu-Seok;Kim, Hye-Jeong;Lee, Jong-Min;Chang, Yong-Min;Kim, Yong-Seon;Kang, Duk-Sik;Ryeom, Hun-Kyu
    • Investigative Magnetic Resonance Imaging
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    • v.9 no.2
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    • pp.109-116
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    • 2005
  • Purpose : To determine the usefulness of additional Mn-DPDP MRI for preoperative evaluation of the patients with colorectal cancers by comparison of dual-phase CT scan, Mn-DPDP enhanced MRI and combination of CT and MRI. Materials and Methods : Fifty-three colorectal cancer patients with 92 metastatic nodules underwent dualphase (arterial and portal) helical CT scan and Mn-DPDP MRI prior to surgery. The indication of MRI was presence or suspected of having metastatic lesions at CT scan and/or increased serum carcinoembryonic antigen (CEA) levels (10 ng/mL or more). The diagnosis was established by the combination of findings at surgery, intraoperative ultrasonography, and histopathologic examination. Two radiologists interpreted CT, MRI, and combination of CT-MRI at discrete sessions and evaluated each lesion for location, size, and intrinsic characteristics. The lesions were divided into three groups according to their diameter; 1cm<, 1-2 cm, and >2 cm. Diagnostic accuracy was evaluated using the alternative-free response receiver operating characteristic method. Detection and false positive rate were also evaluated. Results : In the lesions smaller than 1 cm, detection rate of combined CT-MRI was superior to CT or MRI alone (82%, p=0.036). The mean accuracy (Az values) of combined CT and MRI was significantly higher than that of CT in the lesions smaller than 2 cm (1 cm<, p=0.034; 1-2 cm, p=0.045). However, there was no significant difference between MRI and combined CT-MRI. The false positive rate of CT was higher than those of combined CT-MR in the lesions smaller than 1 cm (28%, p=0.023). Conclusion : Additional MRI using Mn-DPDP besides routine CT scan was helpful in differentiating the hepatic lesions (<2 cm) and could improve detection of the small hepatic metastases (<1 cm) from colorectal carcinoma.

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The Correlation Analysis of Ejection Fraction: Comparison of $^{201}Tl$ gated Myocardial Perfusion SPECT and Echocardiography ($^{201}Tl$ 게이트 심근관류 SPECT 및 심초음파의 좌심실 구혈률 상관관계 비교)

  • Yoon, Soon Sang;Ryu, Jae Kwang;Cha, Min Kyung;Lee, Jong Hun;Kim, Sung Hwan
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.2
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    • pp.49-56
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    • 2012
  • Purpose : Gated myocardial perfusion SPECT provides not only myocardial perfusion status, but various functional parameters of left ventricle (LV). The purpose of this study was to analyze ejection fraction (EF) for correlation and difference between $^{201}Tl$ gated myocardial perfusion SPECT and echocardiography depending on extent of perfusion defect, gender and LV volumes. Materials and Methods : From April 2011 to May 2012, we analyzed 291 patients (male:female =165:126; mean: $64.6{\pm}10.8$ years) who were examined both $^{201}Tl$ gated myocardial perfusion SPECT and echocardiography at less than 7 days apart in our hospital. 101 patients showed perfusion defect and the rest of the people without any defect. We applied automatic analysis (Quantitative gated SPECT, QGS), and calculated EF, End-diastolic volume (EDV) and End-systolic volume (ESV) from Stress (G-Stress) and Rest (G-Rest) studies. And we analyzed the correlation and difference for EF between $^{201}Tl$ gated SPECT and echocardiography. Results : The correlation of LVEF among G-Stress, G-Rest and echocardiography was quite a good (G-Stress vs. G-Rest: r=0.909, G-Stress vs. echocardiography: r=0.833, G-Rest vs. echocardiography: r=0.825). And there were significant differences in EDV, ESV and EF in total patients (p<0.01). The normal group showed significant difference in EF (p<0.01) and the group with perfusion defect also demonstrated significant difference (a group with reversible defect: p<0.01, fixed defect: p<0.01) depending on extent of perfusion defect. We analyzed difference in normal group by gender. In normal group, there was no significant difference (p>0.05) in EF from men. However, there was a significant difference (p<0.01) from women. When we classified two groups by average size of EDV in Korean women, there was no significant difference in a group of above average size of EDV (p>0.05). Conclusion : When compared among Stress and Rest of $^{201}Tl$ gated SPECT and echocardiography, we confirmed that there was a good correlation for LVEF. But there were significant differences among three studies. And extent of perfusion defect, gender and LV volumes are independent determinants of the accuracy of LVEF. So, it is hard to compare and interchange quantitative indices among modalities. We should take additional researches to prove results of our study.

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LCD 연구 개발 동향

  • 이종천
    • The Magazine of the IEIE
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    • v.29 no.6
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    • pp.76-80
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    • 2002
  • 'Liquid Crystal의 상전이(相轉移)와 광학적 이방성(異方性)이 1888년과 1889년 F. Reinitzer와 O. Lehmann에 의해 Monatsch Chem.과 Z.Physikal.Chem.에 각각 보고된 후 부터 제2차 세계대전이 끝난 뒤인 1950년대 까지는 Liquid Crystal을 단지실험실에서의 기초학문 차원의 연구 대상으로만 다루어 왔다. 1963년 Williams가 Liquid Crystal Device로는 최초로 특허 출원을 하였으며, 1968년 RCA사의 Heilmeier등은 Nematic 액정(液晶)에 저주파(低周波) 전압(電壓)을 인가하면 투명한 액정이 혼탁(混濁)상태로 변화하는 '동적산란(動的散亂)'(Dynamic Scattering) 현상을 이용하여 최초의 DSM(Dynamic Scattering Mode) LCD(Liquid Crystal Display)를 발명하였다. 비록 150V 이상의 높은 구동전압과 과소비전력의 특성 때문에 실용화에는 실패하였지만 Guest-Host효과와 Memory효과 등을 발견하였다. 1970년대에 이르러 실온에서 안정되게 사용 가능한 액정물질들이 합성되고(H. Kelker에 의해 MBBA, G. Gray에 의한 Cyano-Biphenyl 액정의 합성), CMOS 트랜지스터의 발명, 투명도전막(ITO), 수은전지등의 주변기술들의 발전으로 인하여 LCD의 상품화가 본격적으로 이루어지게 되었다. 1971년에는 M. Shadt, W. Helfrich, J.L. Fergason등이 TN(Twisted Nematic) LCD를 발명하여 전자 계산기와 손목시계에 응용되었고, 1970년대 말에는 Sharp에서 Dot Matrix형의 휴대형 컴퓨터를 발매하였다. 이러한 단순 구동형의 TN LCD는 그래픽 정보를 표시하는 데에는 품질의 한계가 있어 1979년 영국의 Le Comber에 의해 a-Si TFT(amorphous Silicon Thin Film Transistor) LCD의 연구가 시작되었고, 1983년 T.J. Scheffer, J. Nehring, G. Waters에 의해 STN(Super Twisted Nematic) LCD가 창안되었고, 1980년 N. Clark, S. Lagerwall 및 1983년 K.Yossino에 의해 Ferroelectric LCD가 등장하여 LCD의 정보 표시량 증대에 크게 기여하였다. Color화의 진전은 1972년 A.G. Ficher의 셀 외부에 RGB(Red, Green, Blue) filter를 부착하는 방안과, 1981년 T. Uchida 등에 의한 셀 내부에 RGB filter를 부착하는 방법에 의해 상품화가 되었다. 1985년에는 J.L. Fergason에 의해 Polymer Dispersed LCD가 발명되었고, 1980년대 중반에 이르러 동화상(動畵像) 표시가 가능한 a-Si TFT LCD의 시제품(試製品) 개발이 이루어지고 1990년부터는 본격적인 양산 시대에 접어들게 되었다. 1990년대 초에는 STN LCD의 Color화 및 대형화(大型化) 고(高)품위화에 힘입어 Note-Book PC에 LCD가 본격적으로 적용이 되었고, 1990년대 후반에는TFT LCD의 표시품질 대비 가격경쟁력 확보로 인하여 Note-Book PC 시장을 독점하기에 이르렀다. 이후로는 TFT LCD의 대형화가 중요한 쟁점으로 부각되고 있고, 1995년 삼성전자는 당시 세계최대 크기의 22' TFT LCD를 개발하였다. 또한 LCD의 고정세(高情細)화를 위해 Poly Si TFT LCD의 개발이 이루어졌고, 디지타이져 일체형 LCD의 상품화가 그 응용의 폭을 넓혔으며, LCD의 대형화를 위해 1994년 Canon에 의해 14.8', 21' 등의 FLCD가 개발되었다. 대형화 방안으로 Tiled LCD 기술이 개발되고 있으며, 1995년에 Sharp에 의해 21' 두장의 Panel을 이어 붙인 28' TFT LCD가 전시되었고 1996년에는 21' 4장의 Panel을 이어 붙인 40'급 까지의 개발이 시도 되었으며 현재는 LCD의 특성향상과 생산설비의 성능개선과 안정적인 공정관리기술을 바탕으로 삼성전자에서 단패널 40' TFT LCD가 최근에 개발되었다. Projection용 디스플레이로는 Poly-Si TFT LCD를 이용하여 $25'{\sim}100'$사이의 배면투사형과 전면투사형 까지 개발되어 대형 TV시장을 주도하고 있다. 21세기 디지털방송 시대를 맞아 플라즈마디스플레이패널(PDP) TV, 액정표시장치 (LCD)TV, 강유전성액정(FLCD) TV 등 2005년에 약 1500만대 규모의 거대 시장을 형성할 것으로 예상되는 이른바 '벽걸이TV'로 불리는 차세대 초박형 TV 시장을 선점하기 위하여 세계 가전업계들이 양산에 총력을 기울이고 있다. 벽걸이TV 시장이 본격적으로 형성되더라도 PDP TV와 LCD TV가 직접적으로 시장에서 경쟁을 벌이는 일은 별로 없을 것으로 보인다. 향후 디지털TV 시장이 본격적으로 열리면 40인치 이하의 중대형 시장은 LCD TV가 주도하고 40인치 이상 대화면 시장은 PDP TV가 주도할 것으로 보는 시각이 지배적이기 때문이다. 그러나 이러한 직시형 중대형(重大型)디스플레이는 그 가격이 너무 높아서 현재의 브라운관 TV를 대체(代替)하기에는 시일이 많이 소요될 것으로 추정되고 있다. 그 대안(代案)으로는 비교적 저가격(低價格)이면서도 고품질의 디지털 화상구현이 가능한 고해상도 프로젝션 TV가 유력시되고 있다. 이러한 고해상도 프로젝션 TV용으로 DMD(Digital Micro-mirror Display), Poly-Si TFT LCD와 LCOS(Liquid Crystals on Silicon) 등의 상품화가 진행되고 있다. 인터넷과 정보통신 기술의 발달로 휴대형 디스플레이의 시장이 예상 외로 급성장하고 있으며, 요구되는 디스플레이의 품질도 단순한 문자표시에서 그치지 않고 고해상도의 그래픽 동화상 표시와 칼라 표시 및 3차원 화상표시까지 점차로 그 영역이 넓어지고 있다. <표 1>에서 보여주는 바와 같이 LCD의 시장규모는 적용분야 별로 지속적인 성장이 예상되며, 새로운 응용분야의 시장도 성장성을 어느 정도 예측할 수 있다. 따라서 LCD기술의 연구개발 방향은 크게 두가지로 분류할 수 있으며 첫째로는, 현재 양산되고 있는 LCD 상품의 경쟁력강화를 위하여 원가(原價) 절감(節減)과 표시품질을 향상시키는 것이며 둘째로는, 새로운 타입의 LCD를 개발하여 기존 상품을 대체하거나 새로운 시장을 창출하는 분야로 나눌 수 있다. 이와 같은 관점에서 현재 진행되고 있는 LCD기술개발은 다음과 같이 분류할 수 있다. 1) 원가 절감 2) 특성 향상 3) New Type LCD 개발.

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