• Bulletin of the Korean Space Science Society
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• 2010.04a
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• pp.35.4-35.4
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• 2010

GPS 위성 중 세슘시계를 보유한 Block IIA 위성은 시계 성능의 저하로 시계 예측 모델의 정확도가 떨어지고 있다. 이 연구에서는 세슘원자 위성시계의 성능을 살펴보고 예측 정확도를 높일 수 있는 모델을 제시하고자 한다. IGS Final 위성시계자료를 수집하여 Allan variance를 통해 각 위성별 안정도를 확인하고, Fourier 변환을 통해 각 위성별 주기성을 살펴본다. 예측 모델의 계수를 결정하기 위해 예측 하루 전의 IGS Rapid 자료를 이용하고, 3시간, 6시간, 12시간, 24시간 간격의 예측 결과들을 IGS Final 결과와 비교하여 예측 모델의 정확도를 확인한다. 또한 IGS에서 제공하고 있는 Ultra-Rapid 예측자료와 비교하여 실시간 정밀 위치 결정 분야에 활용 가능성을 확인한다.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1625-1628
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• 2006

The (-)-pimara-9 (11), 15-dien-19-oic acid, acanthoic acid was extracted from the roots of Acanthopanax koreanum using bioassay-guided isolation of a MeOH extract. Acanthoic acid was assayed against Streptococcus mutans and Staphylococcus epidermidis causing dental caries and opportunistic pathogen. The minimum inhibitory concentration (MIC) of acanthoic acid against Streptococcus mutans and Staphylococcus epidermidis was 2 and 4 ${\mu}g/mL$, respectively, which was much lower than those of other natural antimicrobial agents such as 8 ${\mu}g/mL$ of tanshinone IIA. Acanthoic acid also significantly inhibited the growth of other cariogenic bacteria such as Streptococcus sobrinus and Streptococcus sanguis, and Streptococcus grodenii in the MIC range of 4${\sim}$32 ${\mu}g/mL$. Our findings suggest that acanthoic acid could be employed as a potential antibacterial agent for preventing dental caries and skin infections.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.446-448
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• 2002

The inhibitory activity of tanshinones from Salvia miltiorrhiza was tested on rat liver diacylglycerol acyltransferase (DGAT). Cryptotanshinone (1) and 15,16-dihydrotanshinone I (3) exhibited potent DGAT inhibitory activities dose-dependently with $IC_{50}$ values of $10.5 {\;}{\mu\textrm{g}}/ml{\;}and{\;}11.1{\;}{\mu\textrm{g}}/ml$. However, tanshinone IIA (2) and tanshinone I (4) showed very weak inhibition ($IC_{50}{\;}value:{\;}>{\;}250{\;}{\mu\textrm{g}}/ml$). A dihydrofuran moiety was seemed to be responsible for the stronger inhibitory activity

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.25 no.4
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• pp.262-295
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• 2021

This paper introduces mono-implicit general linear methods, a special class of general linear methods, which are implicit in the output solution for the numerical integration of differential algebraic equations. We show how L-stable inherent Runge-Kutta members can be derived. The procedures for implementation have been discussed. The numerical test on the problem considered shows that the methods have improved accuracy when compared to RADAU IIA and the results from MATLAB ode15s, which have been taken as our reference solution.

• Archives of Pharmacal Research
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• v.12 no.3
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• pp.181-185
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• 1989

When 3-acetyl coumarin derivatives are treated with bromine, 3-(w-bromoacetyl) coumarin derivatives are obtained. The reaction of 3-(w-bromoacetyl)coumarin derivatives with thiourea or with amines for two hours leads to the formation of 2-Amino-4-(3-coumarinyl) thiazole or 3-(w-aminoacetyl) coumarin derivatives, respectively. While 3-(w-bromoacetyl) coumarin derivatives react with amines for 5-8 hours to yield imino derivatives of 3-(w-aminoacetyl) coumarin. The antimicrobial activity of Ia-b, IIa-c, IVc-f, IVh and V$_{c}$, f, h, k, m, and q was studied.d.

• Journal of Chest Surgery
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• v.36 no.6
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• pp.411-417
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• 2003

Esophageal cancer is an aggressive disease with a poor prognosis. Recently, neoadjuvant therapy been used in an attempt to increase the long term survival but has not been shown as a clear advantage. We reviewed the recurrence and survival after complete resection of esophageal cancer without neoadjuvant therapy. Material and Method: From December 1994 to December 2001, 182 consecutive patients who underwent intrathoracic esophagectomy, transthoracic esophagogastrostomy and two-field lymph node dissection for esophageal canter without neoadjuvant therapy were studied retrospectively. Result: There were 167 men and 15 women. The median age was 65 years (range, 40 to 90 years). The tumor was located in the upper third part of the esophagus in 7 patients (3.8%), middle third in 86 (47.3%), and lower third in 89 (48.9%). The postsurgical stage were as follows: stage 0 in 2 patients (1.1%), stage I in 32 (17.6%), stageIIA in 47 (25.8%), stage IIB in 25 (13.7%), stage III in 54 (29.7%), stage IVA in 10 (5.5%), and stage IVB in 12 (6.6%). The in-hospital mortality rate was 3.8% (7 patients) and complications occurred in 65 patients (35%), Follow-up was complete in 95.6%. The recurrence occurred in 56 patients (30.8%) and the overall 5-year disease free rate was 55%. The overall 5-year survival rate was 57%; it was 80% for patients in stage I, 65% in stage IIA, 58% in stage IIB, 48% in stage III, and 40% in stage IVB. The overall 5-year survival rate of patients with postoperative adjuvant therapy was 59% compared to 34% in patients without postoperative adjuvant therapy (p<0.05). Conclusion: The most effective therapy for esophageal cancer may be complete resection. More aggressive surgical therapy and adjuvant therapy may improve the long-term survival, even for advanced stage esophageal cancer.

• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.569-586
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• 1994

The purpose of this study is to investigate the effect of loss of incisal function on the thickness, growth activities, ultrastructure of the condylar cartilage and on the muscle fibers of masseter superlicialis, anterior belly of digastric muscle in the growing rats. 37 day-old-rats of which incisors had been trimmed every day received soft diet from weaning and were studied by the autoradiography, electron microscopy and muscle histochemistry. The results obtained were as follows : The thickness of the fibrous, proliferative layer in superior, posterosuperior portion of the condylar cartilage was significantly(p<0.01) reduced in experimental groups and the decrease rate of fibrous layer thickness was greater in posterosuperior portion than in superior portion of cartilage and was greater than in proliferative layer. In normal group, more cells of posterosuperior portion moved more rapidly towards the medullary cavity. In experimental group, the labelling index of posterosuperior portion was decreased in proliferative layer at 2 hours, in transitional layer at 1, 2 days, in hypertrophic layer at 4 days after injection relative to posterosuperior portion of control group. But labelling index of superior portion was not different from that of control group at all time course after injection. From the muscle histochemistry, the diameter of type IIB fibers in masseter superficialis muscle, type IIA, type IIB fibers in anterior belly of digastric muscle decreased significantly(p<0.01) relative to controls in experimental group. From electron microscopic study, in the fibrous layer of the posterosuperior portion of condylar cartilage in normal group, many fibroblast like cells near the joint cavity showed extensive remodelling activities in ultrastructure. There was no morphological changes between experimental and control group in all cartilage cell layers of superior portion but cells near the joint cavity in fibrous layer of posterosuperior portion of experimental group showed morphologically inactive state relative to control group.

• Radiation Oncology Journal
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• v.3 no.2
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• pp.103-111
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• 1985

The early carcinoma of the uterine cervix may be treated by either radical surgery or radical radiotherapy according to the patient's characteristics, and the survival is high with either treatment. But, because of the size of the lesion, metastasis to lymph nodes, and vascular space invasion by tumor have all been shown to influence recurrence and survival, postoperative radiotherapy may be considered as their histopathologic finding after radical surgery. However, there are still debates on the increasing survival rates with postoperative radiotherapy. Two hundreds and three patients with carcinoma of the uterine cervix who were treated with postoperative radiotherapy from February 1979 to September 1982 in the Department of Therapeutic Radiology, Seoul National University were analyzed and following results were obtained. 3-year actuarial survival rate and 3-year disease free sruvival rate were $83.4\%\;and\;73.4\%$ respectively and 3-year actuarial survival rates by stages were $90.7\%$ for IB, $69.6\%$ for IIA, and $85.2\%$ for IIB. 3-year disease free survival rates by stage IB, IIA, IIB were $79.8\%,\;07.8\%,\;68.3\%$ respectively. The overall failure rate was $25.1\%(51/203)$; local recurrence rate was $8.4\%$, distant metastasis rate was $14.3\%$ and simultaneous local recurrence and distant metastasis was $2.4\%$. Failure rates by stages were $19.8\%$ (18/19) for IB, $29.1\%$ (16/55) for IIA and $29.8\%$ (17/57) for IIB. The overall acute complication rate was $57.6\%$; tolerable cases was $50.2\%$ and severe cases was $7.4\%$. Late complication rate was $7.9\%$ and the major late complication were intestinal obstruction. aggravated urinary symptom, radiation cystitis in order of frequency.

• Radiation Oncology Journal
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• v.24 no.2
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• pp.123-127
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• 2006

Purpose: The purpose of this study was to investigate the clinical findings, treatment, and outcome of patients with glassy cell carcinoma of cervix. Materials and Methods: We reviewed all cases of glassy cell carcinoma of the uterine cervix confirmed and treated at the Dongsan Medical Center, Keimyung University, between January 1993 and December 2005. There were 7 cases with histopathologically confirmed gassy cell carcinoma. A tumor was diagnosed as glassy cell carcinoma if over 50% of the tumor cell type displayed glassy cell features. Six patients with stage IB had radical hysterectomy and bilateral pelvic node dissection, and 2 of them received adjuvant external pelvic irradiation with concurrent chemotherapy. Remaining one patient with stage IIA had curative concurrent chemoradiotherapy with external pelvic irradiation and brachytherapy. Results: There were 7 patients diagnosed as glassy cell carcinoma among the 3,745 (0.2%) patients of carcinoma of uterine cervix. The mean age of 7 patients was 44 years with range of 35 to 53 years of age. The most frequent symptom was vaginal bleeding (86%). By the punch biopsy undertaken before treatment of 7 cases, 2 only cases could diagnose as glassy cell carcinoma of uterine cervix, but remaining of them confirmed by surgical pathological examination. The mean follow up duration was 73 months with range of 13 to 150 months. All 7 patients were alive without disease after treatment. Conclusion: Glassy cell carcinoma of the uterine cervix is a distinct clinicopathologic entity that demonstrates an aggressive biologic behavior. However for early-stage disease, we may have more favorable clinical outcome with radical surgery followed by chemoradiothery.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.2 no.2
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• pp.125-137
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• 1997

To study the vertical variation of heavy metal and Rare Earth Element (REE) contents in deep-sea sediments, eighteen cores were sampled from the Korea Deep-sea Environmental Study (KODES)-96 area in the C-C zone (Clarion-Clipperton fracture zone), northeast equatorial Pacific. Sediment columns can be divided into three units based on sediment colors and geochemical characters; uppermost Unit I with brown color, middle Unit II with pale brown color and smaller Ni/Cu ratio than the ratio in Unit I, and lowermost Unit III with dark (brown) colors and higher contents of Mn, Ni, Cu, and REEs than those in Unit I and II. Unit II can be divided more into two layers of upper Unit IIa and lower Unit IIb. Unit IIb is characterized by high contents of Cu, 3+REEs (REEs except Ce), smectite, and severely deteriorated fossil tests. Unit III can also be divided into two units; upper Unit IIIa with dark brown color, and lower Unit IIIb with black color and enriched Mn and Fe. The KODES area was located near from the East Pacific Rise (EPR) When Unit III Sediments were deposited, considering the hiatus between Unit II and III (Quaternary-Tertiary boundary) and the spreading rate (10 cm/yr) and direction (north southern west) of the Pacific plate from the EPR. High contents of Mn and Fe in Unit IIIb may be related with hydrothermal influence from the EPR. Meanwhile, Unit IIb (about 2~3 Ma) and Unit III (11~30 Ma) layers were probably formed near (or under) the equatorial high productivity zone, and accordingly received a lot of organic materials. As a result, Cu and 3+REEs, closely associated with organic materials, are enriched in smectite and/or Ca-P composites (fish bone debrise, biogenic apatite) after decomposition and reprecipitation on the sea floor. Higher contents of Cu and 3+REEs in Unit IIb and III are suggested to be the result of abundant supply of organic substances in the equatorial high productivity zone.