• Macromolecular Research
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• 제15권3호
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• pp.205-210
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• 2007

Collagen is the major structural protein of connective tissues. It can be used as a prosthetic biomaterial applicable to artificial skin, tendon, ligaments, and collagen implants. The objective of this study is to investigate the possibility of realizing wound dressing medical products by the synthesis of composite materials with collagen and a biodegradable polymer, PLLA, via a surface modification process. Type I collagen was obtained from pig skin by a separation process. The structural characteristics of the extracted collagen were confirmed by SDS-polyacrylamide (PAcr) gel electrophoresis (PAGE) and FTIR. Also, PLLA-g-PAcr was synthesized by the radical polymerization of acrylamide initiated by AIBN in the presence of PLLA. The surface of PLLA was modified by the presence of the acrylamide residues. The structural characteristics of the copolymer were analyzed by FTIR, $^1H-NMR$ and contact angle measurements. The water uptake and WVTR of the collagen/PLLA-g-PAcr composite tended to increase with increasing collagen concentration and with decreasing EDC concentration.

• 대한화장품학회지
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• 제30권1호
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• pp.59-62
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• 2004

본 연구는 다양한 종류의 에멀젼에 전단응력을 가하며 그때 일어나는 에멀젼의 상 변이를 전기, 유변학적 특징을 통해 실시간으로 측정해보는 것이다. 전기 전도도의 변화는 자체 제작한 JELL $I^{TM}$ (Joint Electro-rheometer for Liquid-Liquid Inversion) 칩을 이용하였으며, 동시에 유변물성측정장치(rheometer)를 이용하여 유변물성의 변화를 측정하였다. JELL $I^{TM}$ 과 인조 피부를 유변물성측정장치 사이에 장착하고 그 사이에 다양한 종류의 에멀젼을 얇게 발라준 후, 일정한 전단응력을 주며 시간에 따른 저항과 전도값의 변화를 측정하였다. O/W 제형의 경우 시간에 따라 저항값이 커지는 경향을 보였으며 저항값은 내부 상이 많을 수록 더 급격한 변화를 나타냈다. 이때의 점도 변화를 보면, 저항값의 변화가 클수록 점도의 변화도 큼을 볼 수 있었다. 이것은 내부 상의 파괴로 인해 외부의 힘에 저항하는 힘이 약해졌기 때문이라고 예상된다. 이런 결과를 이용하여 전단응력에 의한 에멀젼 상 변이 특성과 정도를 실시간, 정량적 비교할 수 있었다., 정량적 비교할 수 있었다.

• 패션비즈니스
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• 제8권3호
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• pp.10-19
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• 2004

The purpose of this research is to reveal the antimicrobial activity of pet-dog clothes by investigating the bacteria resistance of 4 kinds of pet-dog clothes materials. 1. Investigation Results of Pet-Dog Clothes 64.7% of 150 survey participants, revealed they had pet-dog clothes. Hand laundering was 67.0%, while the laundering of both human and animal clothes was 9.2%. The greatest washing frequency was once every 2 weeks. So, the subjects didn't seem to think high of hygienic matters. Even though no if any relations were reported by 34.7% of the subjects, there were some experiences like sneezing or coughing (41.3%), slight itching (20.7%), and acute skin allergies. There were such hugging methods as heart to heart to the center (22.7%), face to face and around the mouth (16.7%), and below the heart with the dog's face outward (15.3%). Thus, hugging the dog near the pet-lover's face seems to be the cause of respiratory diseases including sneezes and coughs. 2. Results of the Anti-Bacteria Experiment of Pet-Dog Clothes Materials According to the analysis of the germs collected and cultured in this study to reveal the properness of pet-dog clothes materials, they were bacteria or bacilli in shapes. Spore growth was active in the order of such experimental materials as artificial leather > cotton > cotton/ nylon > polyester (finest thread). In terms of germ groups, the order was polyester(finest thread) > cotton > cotton/ nylon > artificial leather.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.129-130
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• 1994

The science of toxicology is the understanding of the mechanisms by which exogenous agents produce deleterious effects in biological systems. The actions of chemicals such as drugs are ultimately exerted at the cellular and gene levels. Over the past decade. several in vitro alternative methods such as cultured cells for assessing the toxicity of various xenobiotics have been proposed to reduce the use of animals. In this workshop three advanced methods will be presented. These methods are novel important models for toxicologic studies. Dr. Tabuchis group has establishcd two immortalized gastric surface mucosa cell lines from the pminary cultore of gastric fundic mucosal cells of adult transgenic mice harboring a temperature sensitive simian virus 40 large T-anugen gene. As the immortalized cell lines of various tissues possess unique characteristics to maintain their normal functions for several months, these cell lines are extremely useful for not only toxicity testing but also pharmacological screening in new drug development. Professor Funatsu have studied the formation of spherical multicelluar aggregates of adult rat hepatocytes(spheroid) having tissue like structure. The sphcroid shown thre is a prototype module of an artificial liver support system. Thus, the urea synthesis activity of the artificial liver was maintained at least to days in 100％ rat blood plasma. Dr. Takezawa and his coworkers have developed a novel culture system of multicellular spheroids considered 〃organoids〃 by utilizing a thermo-responsive polymer as a substratum of anchorage dependent cells. His final goal is to reconstitute the organoids of various normal organs, e.g., liver, skin etc. and also abnormal deseased organs such as tumor.

• Steel and Composite Structures
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• 제43권6호
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• pp.689-706
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• 2022

Thin-walled square concrete-filled double steel tubular (CFDST) columns composed of the inner circular tube filled with concrete can be used to carry the large axial loads or strengthen existing CFST columns in composite constructions. This paper reports an experimental program carried out on short square CFDST columns loaded concentrically. The influences of important column parameters on the post-buckling performance of such columns are investigated. Test results exhibit that the inner circular tube significantly improves the ultimate loads and the ductility of such columns compared to conventional concrete-filled steel tubular (CFST) and double-skin CFST (DCFST) columns with an inner void. A mathematical model developed is used to simulate the ultimate strengths and load-strain curves of such columns loaded axially. Furthermore, the ultimate strengths of such columns are predicted using existing codified design models for conventional CFST columns as well as the formulas proposed by previous researchers and compared against a large database comprising 500 CFDST columns. Lastly, an accurate artificial neural network model is developed for the practical applications of such columns under axial loading.

• Archives of Plastic Surgery
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• 제34권5호
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• pp.593-598
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• 2007

Purpose: Talipes equinus deformity is defined as impossibility of heel weight-bearing and lacking of improvement of toe-tip gait despite sufficient duration of conservative treatment. The incidence of equinus deformity induces post-traumatic extensive soft tissue defect and subsequently increases it. Severe equinus deformities of the foot associated with extensive scarring of the leg and ankle were corrected using achilles Z-lengthening and free-tissue transfer. Methods: Free radial forearm flap was done in nine cases of eight patients from January 2000 to November 2006. Causes of deformity were post-traumatic contracture (one patient) and post-burn scar contracture (seven patients). Seven patients were male, one patient was female. Mean age was 32.1 (range, 10-57). Flap donors were covered with artificial dermis ($Terudermis^{(R)}$) and split thickness skin graft (five cases), and medium thickness skin graft only (four cases). Results: The size of flaps varied from $6{\times}12$ to $15{\times}12cm$ (average, $12{\times}7.8cm$). Achilles tendon was lengthened 4.2cm on average. Free radial forearm flap was satisfactory in all cases. All patients could ambulate normally after the surgery. Cases having donor coverage with $Terudermis^{(R)}$ were aesthetically better than those having skin grafts only. Conclusion: This study suggested that severe equinus deformities associated with extensive scarring of the leg and ankle can be corrected effectively free radial forearm flap and Achilles tendon lengthening.

• 한국어류학회지
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• 제22권2호
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• pp.96-104
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• 2010

멸조위기종인 묵납자루 Acheilognathus signifer의 종복원을 위한 인공수정을 실시하는 과정에서눈과 피부의 색소발현이 결여된 백색증 개체가 출현하였다. 정상 묵납자루와 백색증 개체간 색소발현과 형태의 차이여부를 알아보기 위하여 몸통, 지느러미 눈 등 총 10개 부위에 대한 조직학적 검사를 실시하였다. 그 결과 정상 묵납자루의 경우, 멜라닌세포는 빛에 쉽게 노출되는 등부위와 상미병부, 맥락막-망막색소상피층 및 홍채에서 다량으로 분포하였다. 반면에 백색증 개체에서는 멜라닌세포가 등 부위와 등지느러미, 그리고 꼬리지느러미에서 아주 소량으로 분포하고 있었으며 눈의 맥락막-망막색소상피층 및 홍채에서는 색소결핍 현상이 뚜렷하게 관찰되었다.

• 혜화의학회지
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• 제25권1호
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• pp.119-132
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• 2016

Objectives : The aim of this study is to investigate the effect of natural carbonated hot spring water (NCHW) on DNCB-induced NC/Nga mice, an atopic dermatitis (AD) model. Methods :At first, NC/Nga mice were prepared and induced to have atopic lesion on their back skin by dinitrochlorobenzene (DNCB). They swam for 20 minutes everyday in tanks where the one is filled with $28^{\circ}C$ NCHW, the other is with $25^{\circ}C$ carbonated hot spring water and another is with artificial carbonated hot spring water (ACHW). After 3 weeks, We assessed the skin clinical score and macroscopic appearance, total IgE, IgG1 levels, WBC differential counting, IFN-${\gamma}$, IL-4, IL-13, TNF-${\alpha}$ production levels and histological changes. Results : There are meaningful results of improving atopic lesion-state by relieving the count of total IgE, IgG1 levels, WBC differential counting, IFN-${\gamma}$, IL-4, IL-13, TNF-${\alpha}$ production levels and recovering skin clinical score in the group with $28^{\circ}C$ NCHW in comparison with the other groups. Conclusions : The NCHW may have potential as an effective treatment for atopic dermatitis.

• 감성과학
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• 제18권3호
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• pp.93-106
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• 2015

최근 고기능성 제품에 대한 수요가 증가함에 따라 ICT 기능과의 융합을 통한 스마트 의류는 일상생활 분야로 확대되고 있다. 그 중 하나로, 발열 텍스타일 및 제어 모듈을 통해 의복 내 발열기능을 조절하는 스마트 의류에 대한 관심이 높아지고 있으며, 발열 기능을 갖는 스마트 의류의 시장 전망이 높아지고 있으나, 발열 패드 부착위치에 따른 발열 기능의 효용성 및 온열감에 대한 연구는 부족한 실정이다. 본 연구에서는 발열 패드의 위치에 따른 피부온의 변화와 온열감에 대한 실증적 연구를 통하여 발열기능의 스마트 의류 개발을 위한 최적의 발열 위치를 도출하고자 하였다. 이를 위하여 20대 표준체형의 남성 10명을 피험자로 선정하였으며, 영하 $5^{\circ}C$의 인공기후실에서 20분의 안정기, 20분의 처치기, 40분의 회복기를 통해 11군데에서의 피부온, 직장온과 주관적 온열감을 측정, 평가하였다. 최종적으로, 발열패드를 위한 최적의 위치를 도출하고 제시하였다.

• Archives of Plastic Surgery
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• 제33권4호
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• pp.413-422
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• 2006

Purpose: This study was designed to compare the wound healing effect of silk fibroin, alginate and fibroin/ alginate blend sponge with clinically used Nu gauze in a rat skin defect model. Methods: Two full thickness excisions were made on the back of Sprague-Dawley rat. The excised wound was covered with either of the silk fibroin(SF), alginate (SA), or fibroin/alginate blend sponge(SF/SA). On the postoperative days of 3, 7, 10 and 14, the wound area was calculated by image analysis software. At the same time, a skin wound tissue was biopsied. Results: Healing time 50% ($HT_{50}$) of SF/SA sponge treated group was dramatically reduced as compared with that of control treatment. We also found that the $HT_{50}$ of SF/SA sponge was significantly decreased as compared with either those of SF or SA treatment. Furthermore, SF/SA treatment significantly increased the size of epithelialization and collagen deposition as well as the number of PCNA positive cells on epidermal basement membrane as comapred with those of control treatment. Conclusion: Our results suggest that the wound healing effect of SF/SA blend sponge is the best among other treatments including SF and SA during the whole wound healing period.