• Restorative Dentistry and Endodontics
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• 제48권2호
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• pp.12.1-12.11
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• 2023

Objectives: The present study evaluated the pulp response of human mandibular incisors subjected to in-office dental bleaching using gels with medium or high concentrations of hydrogen peroxide (HP). Materials and Methods: The following groups were compared: 35% HP (HP35; n = 5) or 20% HP (HP20; n = 4). In the control group (CONT; n = 2), no dental bleaching was performed. The color change (CC) was registered at baseline and after 2 days using the Vita Classical shade guide. Tooth sensitivity (TS) was also recorded for 2 days post-bleaching. The teeth were extracted 2 days after the clinical procedure and subjected to histological analysis. The CC and overall scores for histological evaluation were evaluated by the Kruskal-Wallis and Mann-Whitney tests. The percentage of patients with TS was evaluated by the Fisher exact test (α = 0.05). Results: The CC and TS of the HP35 group were significantly higher than those of the CONT group (p < 0.05) and the HP20 group showed an intermediate response, without significant differences from either the HP35 or CONT group (p > 0.05). In both experimental groups, the coronal pulp tissue exhibited partial necrosis associated with tertiary dentin deposition. Overall, the subjacent pulp tissue exhibited a mild inflammatory response. Conclusions: In-office bleaching therapies using bleaching gels with 20% or 35% HP caused similar pulp damage to the mandibular incisors, characterized by partial necrosis, tertiary dentin deposition, and mild inflammation.

• 한국작물학회지
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• 제30권4호
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• pp.352-358
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• 1985

건조분말상태의 인삼 및 유사 숙근성 식물간의 구별방법을 확립하기 위하여 단백질 추출과 분리방법을 달리하여 전기영동법에 의해 각 식물의 단백질 pattern 및 분자량을 추정하였던바 그 결과를 요약하면 다음과 같다. 1. 단백질분리는 증류수와 phosphate buffer로 추출하였을 때 가장 잘 되었으며 비교하기가 용이하였다. 2. 단백질추출방법에 따라 각 식물의 minor band는 약관의 차이가 있었으나 major band는 차이가 없었다. 3. 각 식물을 구별할 수 있는 band는 인삼이 45,000 및 66,000 Kd이며 사삼은 32,000∼39,000kd이고 도라지는 39,000Kd에서 double band가 특징적인 band로서 각 식물을 구별할 수 있는 단백질이었다.

• 한국축산식품학회지
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• 제42권2호
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• pp.295-312
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• 2022

Inulin is a non-digestible carbohydrate and a prebiotic that can also act as a fat replacer in various foods. This study examined the effect of replacing vegetable oil with garlic inulin on the quality traits of chicken sausages. Water-based inulin gels were prepared using garlic inulin or commercial inulin to imitate fats in chicken sausages. Chicken sausages were prepared separately replacing vegetable oil with water-based inulin gels to reach final inulin percentages of 1, 2, and 3 (w/w). The control was prepared using 3% (w/w) vegetable oil with no inulin. The physicochemical properties and thiobarbituric acid reactive substance (TBARS) value of prepared sausages were analyzed over 28-d frozen storage. Sausages with 2% garlic inulin recorded higher flavour and overall acceptability scores (p<0.05). Ash, moisture, and protein contents of the sausages were increased with increasing levels of inulin while fat content was reduced from 13.67% (control) to 4.47%-4.85% (p<0.05) in 3% inulin-incorporated products. Sausages incorporated with 2% inulin had lower lightness (L^*) values than the control (p<0.05). Water holding capacity (WHC) was similar (p>0.05) among the samples. During storage L^* value, pH, and WHC decreased while redness (a^*) and yellowness (b^*) values increased in all the samples. In addition, TBARS values were increased during the storage in all samples within the acceptable limits. In conclusion, garlic inulin can be used successfully as a fat substitute in sausages without altering meat quality parameters.

• 한국재료학회지
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• 제33권10호
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• pp.430-438
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• 2023

In this study, we synthesized pH-controlled resorcinol-formaldehyde (RF) gels through the polymerization of two starting materials: resorcinol and formaldehyde. The prepared RF gels were dried using an acetone substitution method, and they were subsequently carbonized under nitrogen atmosphere to obtain carbon xerogels (CX_Y) prepared at different pH (Y). The carbon xerogels were utilized as active materials for coin-type organic supercapacitor electrodes to investigate the influence of pH on the electrochemical properties of the carbon xerogels. The carbon xerogels prepared at lower pH (CX_9.5 and CX_10) exhibited sufficient particle growth, with a three-dimensional network of particles during the RF gel formation, resulting in the development of abundant mesopores. Conversely, the carbon xerogels prepared at higher pH (CX_11 and CX_12) retained densely packed structures of small particles, leading to pore collapse and low specific surface areas. Consequently, CX_9.5 and CX_10 showed high specific surface areas, and provided ample adsorption sites for the formation of electric double layers with electrolyte ions. Moreover, the three-dimensional particle network in CX_9.5 and CX_10 significantly enhanced electrical conductivity. The presence of well-developed mesopores in these materials further facilitated the effective transport of electrolyte ions, contributing to their superior performance as organic supercapacitor electrodes. This study confirmed that pH-controlled carbon xerogels are one of the promising active materials for organic supercapacitor electrodes. Furthermore, we concluded that pH during RF gel formation is a crucial factor determining the electrode performance of the carbon xerogels, highlighting the need for precise pH control to obtain high-performance carbon xerogel electrodes.

• 생명과학회지
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• 제26권8호
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• pp.955-962
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• 2016

본 연구에서는 연제품용 어육 원료의 안정적인 수급과 고품질 연제품 개발을 위한 방안으로 우리나라에서 주로 양식되고 있는 도미를 이용하여 제조한 연육의 어육 겔 특성을 측정하여 도미의 연제품 소재로서의 가능성을 검토하였다. 현재 우리나라에서는 연제품 제조에 이용되는 어육원료는 주로 수입에 의존하고 있으며 국내에서는 저가의 연육이 일부 생산되고 있다. 수입 연육의 경우 대부분 동남아 및 북아메리카로부터 수입한 냉동 연육이 사용되고 있다. 연육의 품질과 등급은 수분함량, 백색도, 겔 특성 등에 의해 결정되어진다. 따라서 본 연구에서는 양식어종인 도미(Pagrus major)를 원료로 하여 전통 수세법으로 연육을 제조하였으며, 도미 유래 연육을 이용하여 어육겔 형성능 및 품질 특성을 겔 강도, 텍스쳐 실험, 백색도, 수분유출정도 및 SDS-page pattern 측정을 통해 검토하였다. 이들 결과는 FA급과 RA급의 시판용냉동명태연육을 이용하여 제조한 어육 겔 특성과 비교하였다. 겔 특성을 검토하기 위해 연육에 2% NaCl를 첨가하여 전체 수분함량이 80%가 되도록 하여 90℃에서 20분간 가열한 소시지 형태의 어육 겔을 제조하였다. 도미 유래 연육의 어육 겔 특성은 stress-strain curve로부터의 겔강도, cutting strength, breaking force 등의 결과 및 텍스쳐 실험을 통한 springiness, cohesiveness, chewiness, brittleness 등의 결과로부터 확인할 수 있었다. 도미 유래 연육의 어육 겔 특성은 시판용 명태연육(FA급과 RA급)의 어육 겔 특성과 비교하였다. 도미연육의 사용은 RA급의 명태연육에 비해 높은 겔 형성능을 나타내었으며, FA급의 명태연육과는 비슷한 정도의 겔 특성을 나타내었다. 이상의 결과로부터 도미를 이용한 고품질 연제품의 개발 가능성을 확인할 수 있었다.

• 보존과학연구
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• 통권7호
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• pp.48-55
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• 1986

The gold crown unearthed from the ancient tombs at Imdang-dong, Kyongsan-gun, Kyongsangbuk-do was in a state of severe corrosion that its original pattern couldn't be identified. Therefore, for the conservation of the relics, the following methods are employed :1. With 10% formic acid are used for the elimination of the bronze-rust and then plated them with gold.2. As a rust-proof treatment, 1% Benzotriazole is used for stem corrosion as well3. For protection and reinforcement of the surface of the relics, 30% incralac agentsare used.4. Pieces of fragments are bonded together by cyanoacrylate and on the backside are coated partially with Araldite for the reinforcement of the glass-wool.5. Silica-gels are kept into the acryl box for perfect maintenance.

• 대한치과의사협회지
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• 제11권8호
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• pp.525-530
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• 1973

True collagenolytic enzymes in animal tissues were first demonstrated by Gross and Lapiere (1962), who showed the ability of such an enzyme in the culture medium of living explants of tadpole tissue to degrade a specific substrate of undenatured collagen under physiological conditions. Recently, tumor-associated collagenolytic activity has been demonstrated in human neoplasm and in ascites V Carcinoma. This investigation have been peforme to determine whether or not a collagen lytic enzyme could e found in isolated solid Tawa sarcoma of Donryu female rat obtained the culture medium. The results were as follows. 1. 11.5mg% of hydroxyproline contained in Donryu rat skin collagen, which was extracted by 0.5M acetic acid. 2. Cultivation of solid Tawa sarcoma tissues on reconstituted rat skin collagen gels showed lysis of adjacent gel after 18 hours, and much more extensive lysis after 5 days. 3. Collagen substrate was not attacked by the common proteolytic enzymes, trypsin, pepsin, and pronase.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.697-700
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• 2001

Iron is an essential nutrient for most organisms, which supplied to them in a protein-iron complex known as ferritin. Ferritins are multimeric proteins found in prokaryotes, plants and animals. They are consisted of spherical shell of 24 subunits defining a cavity of about 8nm in diameter, where an iron core is laid down. Expression of ferritin in recombinant E. coli at $37^{\circ}C$ led to the accumulation of recombinant ferritin. Insoluble form of ferritin was separated from disrupted cells, followed by various primary separation steps with two kinds of buffers. Collected samples from the primary steps were purified by DEAE-cellulose gels packed in a column. The fractions from the DEAE column were assayed to gain the amount and the purity of ferritin by using HPLC and SDS-PAGE.

• Molecular & Cellular Toxicology
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• 제3권4호
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• pp.238-245
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• 2007

Chronic formaldehyde inhalation studies have suggested its relativity to teratogenicity, cancer incidence, neurodegenerative and vascular disorders. Many toxicological data on the formaldehyde toxicity are available, but proteomic results showing complete protein profiles are limited. Therefore, alterations of protein expression patterns upon formaldehyde treatment were investigated in the human lung epithelial cell line. Differentially expressed proteins following formaldehyde treatment were analyzed on 2-dimensional gels, and further analyzed by MALDI-TOF to identify the proteins. Among the identified proteins, 24 proteins were notably up-regulated and 6 proteins were down-regulated. In particular, cytoskeleton related protein named vinculin and Rho GDP dissociation inhibitor which plays a key role in apoptosis increased remarkably.

• 한국세라믹학회지
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• 제25권5호
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• pp.479-487
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• 1988

In this study we studied the function of Glycerol as a DCCA(Drying Control Chemical Additives) in the preparation of silica bulk glas through Sol-Gel method. We used TEOS(Tetra Ethyl Ortho Silicate) and maintained the mixing ratio of TEOS : H2O : EtOH : HCI as 1 : 4 : 4 : 0.0007(mol) and varied glycerol input quantity from 0.1vol% considering the ethnaol input quantity as 100vol%. We investigated the changes from Sol-Gel Synthetic solutions to the glass using DT-TG, FT-IR and other instruments. The results obtained from this experiment showed that the dried gels made from the synthetic solutions containing 0.1-1.0vol% of glycerol were easily heat-treated up to 85$0^{\circ}C$ so that transparant bulk silica glass was prepared.