• Proceedings of the KSMRM Conference
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• 2001.11a
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• pp.170-170
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• 2001

Purpose： To evaluate the relationship between reperfusion hyperemia in reversible cerebral ischem and the degree of programmed cell death. Method： We produced the animal models of reversible cerebral ischemia in 10 cats by mean of middle cerebral artery (MCA) occlusion with transorbital approach. MCA was occluded b microvascular clamp for an hour. MR imaging was performed at 0, 1, 2 days after ischemi and reperfusion. Perfusion (PWI) [Contrast enhanced GRE EPI, TR/TE= 1500/40, 40 Phases, 128 matrix, 12 cm FOV] and diffusion (DWI) (SE EPI, b=0, 500, 1000) weighted images were obtained using Philips Intera 1.57 system. rCBV and ADC maps were calculated wi IDL based postprocessing program. Tissue slices were obtained after the last MR imagin TUNEL, Calbin and Acid-Fuscin staining were done for corresponding slices as MR imagin We investigated the differences of degree of apoptosis in the area of reperfusion hyperemia.

• Archives of Pharmacal Research
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• v.17 no.5
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• pp.348-353
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• 1994

The activity fractionation upon the MeOH extract of the root of trichosanthes kirilowii led to the isolation of eight cucurbitane tritepense namely cucurbitacin .betha. (I), isocucurbitacin .betha.(II), cucurbitacin D(III), isocucurbitacin D(IV), 3-epi-isocucurbitacin .betha(V), dihydrocucurbitain .betha. (VI), dihydroisocucurgbitachin .betha. (VII) and dihydrocucurbitacin E (VIII), as active principles. All isolates were shown to exhibit significant cytotoxicity against cultured human tumor cells, including A-549, Sk-OV-3, Sk-MEL-2, XF-498 and HCT 15, with an exceptionally high potency.

• Journal of the Korean Institute of Telematics and Electronics
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• v.20 no.1
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• pp.45-49
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• 1983

The four-layered(metal/insulator/n epi-layer/p+) controlled inversion devices have been fabricated. The I-V curve showed two characteristic states―an On state and an OFF state which were separated by a negative resistance region. The switching voltage and the holding voltage were about 5.0V and 2.5V, respectively. The switching voltage of the device was decreased by photo illumination while the holding voltage remained unaffected.

• Proceedings of the KSMRM Conference
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• 2003.10a
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• pp.26-26
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• 2003

목적： 본 연구의 목적은 미각자극에 대한 인간 뇌의 활성화 영역을 측정하고 가시화하여 미각의 뇌 활성화 부위에 대한 기초자료를 마련하는데 있다. 대상 및 방법： 5명의 남자 대학생 (평균 24.8세)을 뇌기능 연구의 실험 대상자로 선정하였고, 대상자들은 미각에 이상이 없고 구강수술 경험이 없는 오른손잡이를 대상으로 3번에 걸쳐 EPI 혈액산 소농도의존(blood oxygen level dependent)법을 이용하여 미각자극에 의한 기능적 자기공명영상 실험을 수행하였다. 미각 자극을 위하여 5％의 saline을 사용하였으며 자체적으로 제작한 Stimulator를 사용하여 자극하였다. 자극은 3회의 휴식기간과 2회의 자극기간에 걸쳐 시행하였으며, 각 자극기간은 30초씩 5초 간격으로 이스 당 42개의 영상을 획득했다. Post-processing은 SPM99 (Statistical Parametric Mapping 99, The Wellcome Department of Cognitive Neurology, Oxford 1999)의 correlation법을 사용하여 threshold 0.4∼0.7의 범위에서 통계처리 하였으며, 활성화 영상은 EPI영상과 같은 부위의 T1 강조영상에 overlapping시켰다. 이렇게 얻어진 fMRI 영상으로 활성 영역의 위치를 분석하였다.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1578-1580
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• 2002

The breakdown and on-state characteristics of the multi-RESURF SOI LDMOSFET is presented. P-/n-epi layer thickness and doping concentration is varied from $2{\mu}m{\sim}5{\mu}m$ and $1{\times}10^{15}/cm^3{\sim}9{\times}10^{15}/cm^3$ to obtain optimum breakdown voltage and on-resistance. The breakdown and on-state characteristics of the device is verified by two-dimensional process simulator ATHENA and device simulator ATLAS.

• Journal of Sensor Science and Technology
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• v.18 no.2
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• pp.135-138
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• 2009

$64{\times}1$ forcal plane infrared detector has been fabricated by using HgCdTe epi layer. HgCdTe was grown on GaAs substrate by using metal organic chemical vapor deposition. This paper describes key developments in the epi layer growth and device fabrication process. The performance of IR imaging system is summarized.

• Natural Product Sciences
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• v.21 no.4
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• pp.293-296
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• 2015

A new L-isoascorbic acid derivative epi-leptosphaerin (1) and two known compounds leptosphaerin (2), and verongamine (3) were isolated from sponges of the orders Verongida and Thorectidae. Compounds 1 and 2 are most likely of sponge-associated fungal origin. In the present study, isolated compounds were investigated for their inhibition of soluble epoxide hydrolase (sEH), which is considered a promising target for the management of pain, inflammation, and comorbidities associated with diabetes. Compound 3, verongamine, displayed weak inhibitory activity against sEH with an $IC_{50}$ value $51.5{\pm}1.0{\mu}M$.

• Journal of the Semiconductor & Display Technology
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• v.1 no.1
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• pp.15-19
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• 2002

A new vacuum packaging process in wafer level is developed for the surface micromachining devices using glass silicon anodic bonding technology. The inside pressure of the packaged device was measured indirectly by the quality factor of the mechanical resonator. The measured Q factor was about 5$\times10^4$ and the estimated inner pressure was about 1 mTorr. And it is also possible to change the inside pressure of the packaged devices from 2 Torr to 1 mTorr by varying the amount of the Ti gettering material. The long-term stability test is still on the way, but in initial characterization, the yield is about 80% and the vacuum degradation with time was not observed.

• Journal of Nutrition and Health
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• v.31 no.7
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• pp.1130-1138
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• 1998

The objective of this study was to investigate the relationship between changes in body temperature, adiposity and sympathoadrenal activity in normal weight female college students, eating an instant-noodle lunch in a laboratory setting at ambient temperatures of 22-24.8$^{\circ}C$. Preprandial epinephrine(EPI) concentration, as an indicator of adrenal activity, was inversely and significantly correlated with body weight, body mass index(BMI), and waist girth. Changes in pre- and postprandial EPI concentrations showed positive correlations with % body fat, fat mass, waist girth, hip girth, and waist/hip girth ratio(WHR). The preprandial norepinephrine (NE) concentration was negatively correlated with recovery time from the peak postprandial core temperature to the meal-start core temperature(RTST). However, the NE concentration, an indicator of sympathetic neural activity, was not related to anthropometric measurements in normal weight young women. In conclusion, adrenal activity was negatively associated with adiposity and central body fat distribution. Sympathetic activity was related to body temperature regulation capacity after a meal, but was not related to adiposity in normal weight young women. (Korean J Nutrition 31(7) 1130-1138, 1998)

• Natural Product Sciences
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• v.27 no.2
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• pp.134-139
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• 2021

A new cipadesin limonoid, i.e. 3-epi-cipadonoid C (1), and a new tirucallane triterpene, i.e. hispidol B 3-palmitate (3), have been isolated from the seeds and fruit peels extract of Sandoricum koetjape, respectively. Along with these compounds the known limonoid, cipaferen G (2), and two pentacyclic triterpenes, bryonolic (4) and bryononic (5) acids, were also isolated. The strucrures of the new compounds were elucidated by the analysis of NMR and mass spectral data. Compounds 1 - 5 were evaluated as the inhibitor of receptor tyrosine kinases (EGFR, Epidermal Growth Factor Receptor; HER2, HER4, Human Epidermal growth factor Receptor 2, -4; IGFR, Insulin-like Growth Factor Receptor; InsR, Insulin Receptor; KDR, Kinase insert Domain Receptor; PDGFRα, and PDGFRβ, Platelet-Derived Growth Factor Receptor-α and -β). The results showed only 1 and 3 that have weak activity against InsR.