• 대한핵의학회:학술대회논문집
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• 1967.11a
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• pp.100.3-100.3
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• 1967

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1433-1436
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• 1999

The 2-(2,4-dimethoxyphenyl)-4-MDO (2) underwent polymerization with ring opening as well as cyclization reaction in the presence of various cationic catalysts such as boron trifluoride, trifluoromethanesulfonic acid, p-toluenesulfonic acid, hydrochloric acid and trifluoroacetic acid. They afforded a mixture of the ring-opened poly(keto ether) and 3(2H)-dihydrofuranone derivative. Both the methylene group and oxygen atom of 1,3-dioxolane ring were participated in the reaction with cationic catalyst. The contents of the polymer and cyclization product were variable according to the acid strength of the cationic catalysts.

• Journal of Periodontal and Implant Science
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• v.38 no.4
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• pp.621-628
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• 2008

Purpose: Osteopontin is one of the major non-collagenous protein of hard tissue. Use of peptide domain of biologically active protein has some advantages. The objective of this experimental study is evaluation of periodontal regenerative potency of synthetic peptide gel which containing collagen binding domain of osteopontin in the degree III periodontal defect of beagle dogs. Material and Methods: Experimental degree III furcation defect was made in the mandibular third and fourth premolar of beagles. Regenerative material was applied during flap operation. 8 weeks after regenerative surgery, all animals were sacrificed and histomorphometric measurement was performed to calculate the linear percentage of the new cementum formation and the volume percentage of new bone formation. Result: The linear percent of new cementum formation was 41.6% at control group and 67.1% at test group and there was statistically significant difference. The volume percent of new bone formation was 52.1% at control group and 58.9% at test group. Conclusion: As the results of present experiment, synthetic peptide gel containing collagen binding domain of osteopontin significantly increase new bone and cementum formation in the degree III furcation defect of canine mandible.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.4
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• pp.884-890
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• 2008

This study classified 40 of 10 weeks-old male Sprague Dawley rats which have osteoporosis caused by glucocorticoid(GC) induction into four groups of 10 rats and made the subjects medicated them Eucommia ulmoides Oliver and participate in treadmill exercise. Group I was non-treatment after GC induction; Group II was treadmill exercise after GC induction; Group III was Eucommia ulmoides Oliver feeding after GC induction; Group IV was treadmill exercise and Eucommia ulmoides Oliver feeding after GC induction. In the bone mineral density and bone strength test, there was a statistically significant difference between the group I, II, III compared to group IV(p<0.05). In the osteocalcin level as one of bone formation indexes, there was a statistically significant difference between the group I, II, III compared to group IV(p<0.05). In respect to the calcium there was a statistically significant difference between group I, II, III compared to group IV(p<0.05). In respect to histological findings, the group IV showed mild femur disruption and lytic change on femur section. The above results suggests that Eucommia ulmoides Oliver medicated and treadmill exercise is effective to prevention and treatment of osteoporosis.

• Advances in pediatric surgery
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• v.15 no.1
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• pp.27-37
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• 2009

Neuroblastoma is the most common extracranial solid tumor in children. We retrospectively analyzed the results of neuroblastoma treatment of 191 patients (116 males and 75 females) treated between January 1986 and December 2005 at the Department of Pediatric Surgery and the Department of Pediatrics, Seoul National University Children's Hospital. The mean age at diagnosis was 3.1 years (0.1 yrs - 13.5 yrs). Forty-seven patients were under 1 year of age. The mean follow-up period was 57.3 months (24 days - 19.1 yrs). Patients were classified into two groups according to the completeness of resection of the primary tumor; (1) gross total resection (GTR) and (2) incomplete resection (IR). The number of patients in stages I, II, III, IV, IV-S were 17 (8.9 %), 12 (6.3 %), 43 (22.5 %), 114 (59.7 %), 4 (2.1 %), respectively. GTR was achieved in 120 patients and IR in 71 (22 stage III, 47 stage IV, 1 stage IV-S, 1 brain). Overall survival (OS) was 65.2 % and event-free survival (EFS) was 48.6 %. EFS were 100 %, 75 %, 66.8 %, 31.3 %, 75 % at stage I, II, III, IV, IV-S, respectively. There was no significant difference in EFS according to the completeness of resection. EFS was improved in GTR group (p=ns) of stage III, but by contrast, stage IV patients showed worse EFS in GTR group. EFS was improved significantly after the introduction of autologous stem cell transplantation (ASCT) (58.1% vs. 40.6%, p=.029). The EFS improved significantly after the introduction of ASCT in IR group (p=.009) rather than GTR group (p=ns). The EFS of the patients under 1 year of age (N=47) was better than the patients over 1 year of age (N=144) significantly (75.5 % vs. 39.4 %, p=.0034). The prognosis of neuroblastoma was related to the INSS stage and age at diagnosis. The survival of IR group significantly improved after ASCT.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.426-432
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• 2009

The overall purpose of this study was to investigate the effects of level of isoflavones supplementation on bone metabolism in osteoporosis rats. The effects of level of isoflavones supplementation on calcium and osteocalcin blood level, femur/body weight, bone mineral density(BMD) and bone strength were inspected in this study. This study classified 28 of 12 weeks-old male Sprague Dawley rats which have osteoporosis caused by ovariectomy into four groups of 7 rats and made the subjects medicated them isoflavone. Group I was non-treatment after osteoporosis(control); Group II was low-dose isoflavone(20 mg/kg) feeding after osteoporosis; Group III was middle-dose isoflavone(40 mg/kg) feeding after osteoporosis; Group IV was high-dose isoflavone(80 mg/kg) feeding after osteoporosis; In the calcium and osteocalcin level as one of bone formation indexes, there was a statistically significant difference between the group II, III, IV compared to group I. In respect to the femur/body weight, there was a statistically significant difference between the group II, III, IV compared to group I. In the bone mineral density and bone strength test, there was a statistically significant difference between the group II, III, IV compared to group I. The above results suggests that isoflavone medicated is effective to prevention and treatment of osteoporosis.

• Applied Chemistry for Engineering
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• v.18 no.6
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• pp.562-567
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• 2007

The stereoselective synthesis of chiral terminal epoxide is of immense academic and industrial interest due to their use as versatile starting materials as well as chiral intermediates. In this study, new polymeric chiral Co(salen) complexes bearing tallium (III)chloride and iron (III)chloride (ferric chloride) have been synthesized and characterized. Their catalytic activity and selectivity have been demonstrated for the asymmetric ring opening of various terminal epoxides using water and phenol derivatives as nucleophiles. The easily prepared polymeric complexes exhibited very high enantioselectivity for the asymmetric ring opening of epoxides with $H_2O$ and phenol nucleophiles, providing enantiomerically enriched terminal epoxides (> 98% ee). The system described in this work is very efficient for the synthesis of chiral epoxide, 1,2-diol and ${\alpha}$-aryloxy alcohol intermediates.

• Analytical Science and Technology
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• v.6 no.1
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• pp.131-139
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• 1993

The separation of gallium and indium from the matrix elements such as zinc and other ions, especially form Fe(III) ion was studied for the determination of trace level of them in zinc ores and zinc blendes by inductively coupled plasma atomic emission spectrometry(ICP-AES). Gallium and indium were extracted from the sample solution with a solvent of tributyl phosphate(TBP). The type and concentration of acid, interferences of other ions, the ratio of aqueous phase to organic phase, TBP concentration, sripping efficiency were optimized for the effective extraction. Gallium and indium were separated from other ions in the 5N hydrochloric acid solution of the samples by the extraction with 100% TBP. In this time, Fe(III) was reduced to Fe(II) with hydroxylamine hydrochloride to prevent its coextraction prior to the main extraxtion. After stripped from organic phase by the back-extraction with 0.02N HCl, they were determined in the aqueous phase by ICP-AES. This method was known to be quantitative from the overall extraction of more than 95%.

• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.257-263
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• 1999

Ln-macrocyclic([20]DOTA) complexes, [Ln([20]DPTA)(NO_{3})(H_{2}O)](NO_{3})_{2} \cdotxH_{2}O{Ln(III)=Pr, Sm, Gd, Dy}, which had been synthesized from 2, 6-diformyl-p-cresol(DFPC), was placed in methanol for 2 days, and $[Ln([20]DPTA)(NO_{3})(CH_{3}OH)]^{2+}$ was formed. The equilibrium constants(L) for the substitution of coordinated $CH_{3}OH$ in the Ln-[20]DOTA complexes by various auxiliary ligands, $L_{a}(=monodentate ligands; pyridine, imidazole, triethylamine, diethylamine, piperidine) were determined spectroscopically at $25^{\circ}C$ and 0.1M. The pKa of auxiliary ligand is in the order of pyridine < imidazole < triethylamine < diethylamine < piperidine, however the K has shown the trend of pyridine < imidzole < diethylamine < piperidine < triethylamine.

• Composites Research
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• v.37 no.1
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• pp.15-20
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• 2024

Since the residual stress of hydrogen tank is directly related to durability, it is very important to reduce it for safety. Type II~IV hydrogen tank are manufactured by the filament winding method, in which the fiber is impregnated with resin and wound around the liner. Residual stress in composite is affected by curing conditions and fiber tension etc. In this study, the effect of curing conditions on residual stress was analyzed when manufacturing a Type III hydrogen tank using carbon fiber filament winding process. First, the curing behavior of the epoxy resin was analyzed using a differential scanning calorimetry. Through this, the curing temperature was set to 140℃. During the same curing time, the specimens were cured under 2-stage curing condition that reached 140℃ earlier and a 4-stage curing condition that reached 140℃ later, respectively. After curing, the residual stress of the composite material was measured by the ring slitting method, and the experimental values were compared with numerical values. It was confirmed that there was a significant difference in residual stress according to the optimization of curing conditions.