• Korean Journal of Pharmacognosy
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• v.10 no.2
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• pp.41-53
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• 1979

A 6', 8a-bonded catechin dimer was synthesized by action of phenoloxidase on 2mol (+)-catechins. The same dimer and other two dimers which are also 6', 8a-bonded were isolated from the fresh cortex of Quercus robur. The 4, 8a-bonded and the etherified 4, 8a-bonded dimers were isolated from it. It was discussed about the meaning of the enzymatically produced 6', 8a-bonded dimers in plant cell. The isolated dimers are as following: 1. 6', 8a-bonded dimers: (+)-catechin-(+)-catechin-6', 8a-dimer(IX), (+)-catechin-(+)-gallocatechin-6', 8a-dimar (XIII), (+)-gallocatechin-(+)-catechin-6', 8a-dimer(XIV). 2. 4, 8a-bonded dimers: (+)-catechin-(+)-catechin-4, 8a-dimer(X), (-)-epicatechin-(+)-catechin-4, 8a-dimer (XI), (+) -galloatechin-(+)-catechin-4, 8a-dimer (XII). 3. 4,8a-bonded dimers with ether linkage: etherified(+)-catechin-(+)-catechin-4, 8a-dimer (XV), etherifid (+)-catechin-(+)-gallocatechin-4, 8a-dimer (XVI), etherified (+)-gallocatechin-(+)-catechin-4, 6a-dimer (XVII).

• Polymer(Korea)
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• v.32 no.2
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• pp.189-192
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• 2008

A styrylpyrylium salt (DHSP) was synthesized and then photodimerized to obtain a cyclobutane-type dimer (DHSP dimer). Methacryloyl group was incorporated into DHSP dimer to obtain DMSP dimer. Based on FT-IR analysis of a crosslinked DMSP dimer, it was considered that the cyclobutane structure reversed to styryl C=C bonds upon crack formation. Fluorescence measurement of DHSP in solid state (excitation at 385 nm) showed emission centered at 626 nm, while DHSP dimer revealed very weak emission. Fluorescent emission from microcracks in a film of crosslinked DMSP dimer was observed upon exposure to $330{\sim}385\;nm$ light.

• Bulletin of the Korean Chemical Society
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• v.16 no.11
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• pp.1028-1032
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• 1995

The structure and electronic properties of the Si(100) surface is studied using the atom superposition and electron delocalization method. The energy released when the symmetric dimer surface is reconstructed to form the buckled dimer surface with p(2X2) symmetry is calculated to be 0.99 eV per dimer in the case of ideal clean surfaces. This indicates that the surface dimer buckling is intrinsic from the viewpoint of thermodynamics. The relaxation energy, when water is adsorbed on the clean symmetric dimer surface to form the buckled dimer surface, is 2.25 eV per dimer for appropriate coverages. These results show that H2O molecule could induce a reconstruction of the surface structure through adsorption. The buckling of the surface dimer is, therefore, more favorable under the existence of water vapour. This conclusion supports the recently obtained experimental observations by Chander et al.

• Journal of Life Science
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• v.20 no.10
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• pp.1458-1467
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• 2010

The present study was retrospectively designed to define whether preoperative levels of leukocytes and D-dimer are potentially useful factors in predicting perioperative outcomes of coronary heart disease (CHD). There was no relationship between preoperative leukocyte counts (Pre-OP leukocyte) and preoperative D-dimer levels (Pre-OP D-dimer). Pre-OP leukocyte counts each had positive correlation with cardiac troponin-I, creatine kinase-MB or C-reactive protein (cardiac markers) levels at preoperative and postoperative periods. Pre-OP D-dimer levels were positively associated with each cardiac marker at the same periods. Pre-OP leukocyte counts positively related with aspartate aminotransferase and alanine aminotransferase (liver markers), whereas Pre-OP D-dimer level positively or negatively correlated with bilirubin (liver marker), creatinine (renal marker) or glucose levels at preoperative and/or postoperative periods. Pre-OP leukocyte and Pre-OP D-dimer were inversely associated with Pre-OP high density lipoprotein cholesterol levels or left ventricular ejection fraction. Pre-OP leukocyte counts each had positive correlation operation duration and postoperative mechanical ventilation-time (PMVT), whereas Pre-OP D-dimer levels had positive relationship with PMVT, intensive care unit-staying period and hospitalization. The retrospective data suggest that Pre-OP leukocyte and Pre-OP D-dimer levels may be clinically useful factors for predicting perioperative outcomes in patients with CHD.

• Journal of Veterinary Clinics
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• v.32 no.1
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• pp.5-8
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• 2015

D-dimer is a fibrin degradation product (FDP), a small protein fragment present in the blood after a blood clot is degraded by fibrinolysis. D-dimer concentration is widely used for determining thrombosis and thromboembolism. Because one major cause of thromboembolism is congestive heart failure in human, we investigated the degree and risk of thromboembolism in dogs with different stage of congestive heart failure caused by chronic mitral valvular insufficiency (CMVI). The plasma level of d-dimer was evaluated in 20 healthy dogs and 30 dogs with different stage of congestive heart failure caused by CMVI. The d-dimer concentrations were measured by a commercialized assay kit. The plasma levels of d-dimer were not significantly different between healthy and CMVI dogs. Furthermore, there was no association of d-dimer concentrations to left atrium to aorta (LA/Ao) ratio, left ventricular dimension at diastole to aorta (LVIDd/Ao) ratio and severity of heart failure in our study population. Our study results implied that the degree of thromboembolism in canine heart failure might be minimal or the plasma d-dimer test might not be reliable for detecting thromboembolism in dogs.

• Journal of Veterinary Clinics
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• v.34 no.6
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• pp.401-403
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• 2017

Total 283 dogs were enrolled in this study (control group: 140, patient group: 143). In the patient group, 143 dogs with underlying diseases including immune medicated hemolytic anemia (IMHA) (7), lymphoma (30), hyperadrenocorticism (HAC) (16), trauma (10), pyometra (8), bone fracture (38), peritonitis (13), meningoencephalitis (12) and mitral regurgitation (9) were enrolled in this study. Compared with healthy group, lymphoma, trauma, HAC, and IMHA group showed significantly (P < 0.01) high values of D-dimer and the highest levels in the IMHA group. Additionally, we evaluated the D-dimer level after a week of enoxaparin treatment, and the results showed D-dimer levels of post treatment group were significantly decreased compared to the pre-treatment group in lymphoma, HAC, trauma and IMHA diseases. In the high level D-dimer group, post D-dimer values after enoxaparin treatment had significantly decreased (P < 0.01) compared to levels prior to treatment.

• Journal of the Korean Vacuum Society
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• v.7 no.1
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• pp.5-10
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• 1998

The geometric structure of dimer atoms on clean Si(001) surface was studied using CAICISS. We confirmed that dimer atoms were certainly buckled, and also found that asymmetry (2$\times$1) and c(4$\times$2) were coexisted. The intradimer bond length and the buckling angle of a dimer measured by CAICISS system were 2.3$\pm$0.1 $\AA$ and 18$\pm$$1^{\circ}$, respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.186-186
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• 2011

[100] 방향으로 4$^{\circ}$ 기울어진 Si(001)-2${\times}$1(vicinal surface)을 초고진공하(UHV)에서 청결하게 하고 열처리하면 rebonded-atom을 가진 DB double step과 이 step에 나란한 아홉 개의 dimer를 가진 평균 폭이 4.0 nm인 single-domain의 (001)-2${\times}$1 테라스의 면으로 재구조된다 [그림 a]. 본 연구에서는 이 표면 위에 Sb을 상온에서 증착하여 덮고 후열처리하면(2 ML, 500$^{\circ}C$ 10 분), Sb-dimer가 Si 표면을 한 층 덮고 (001) 테라스의 Sb-dimer 방향이 DA double-step과 수직을 이루는 1${\times}$2 구조를 이룬다는 사실을 STM으로 확인하였다 [그림 b]. 이러한 Sb-passivation의 효과는 표면 Si-dimer의 부분적으로 채워진 dangling-bond를 Sb-dimer의 완전히 채워진 고립쌍(lone-pair)으로 바꿈으로써 표면 자유 에너지를 줄이고, 나아가 계면 Si 층은 bulk에 유사하게 되는 데에 있다. 이 passivation 된 표면은 Ge/Si 등의 heteroepitaxy에 사용할 수 있고, 특히 single-domain을 유지하며 step 방향에 대해 평행인 dimer-row로 이루어져 있어서 원자나 전자의 이동에 비등방적 효과를 증가시킬 것이 예측된다.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1681-1688
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• 2010

Density functional theory was adopted to study the various surface products and their reaction channels focusing on the on-dimer configuration which has not been suggested before. Energetic results show that the most stable on-dimer configuration is the 6,6-[2+2] structure which resembles the typical [2+2] cycloaddition product. The 6,6-[2+2] product is also more stable than any other possible surface structures of inter-dimer configuration further suggesting its existence. Potential energy surface scan along various possible initial surface reactions show that some of the possible on-dimer surface products require virtually no reaction barrier indicating that initial population of on-dimer surface products is thermodynamically determined. Various surface isomerization reaction channels exist further facilitating thermal redistribution of the initial surface products.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.1
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• pp.113-119
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• 2012

The aim of this study was to investigate the differences in blood homocysteine levels and blood d-dimer levels of cerebral infarction patients categorized by Pattern Identification. We studied hospitalized patients within 4 weeks after the onset of stroke who were admitted to the Oriental Internal Medical Department at Semyung University Chungju Oriental Medical Hospital from May 2008 to September 2009. We analyzed risk factors and blood homocysteine levels and blood d-dimer levels accordings to Pattern Identification in Cerebral infarction patients. A total of 49 patients were included in the trial. No statistical significance was noted for any characteristics except body weight and body mass index. Body weight and body mass index were significantly higher Dampness-Phlegm pattern. On past history of patients, prevalence of DM was significantly higher in Fire-Heat pattern than that of other patterns. There was no significant difference of blood homocysteine levels and blood d-dimer levels among Pattern Identification. This study investigated the differences in blood homocysteine levels and blood d-dimer levels of cerebral infarction patients categorized by Pattern Identification. The correlation in homocysteine and d-dimer levels and Pattern Identification was not clarified.