• 한국자기학회지
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• 제12권3호
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• pp.109-116
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• 2002

평면변압기의 설계방법 확립과 응용가능성을 파악하기 위해 입/출력전압이 70V/8.2V인 8W급 플라이-백 평면변압기를 설계하였다. 스위칭 주파수 120kHz에서 인덕턴스는 1650 $\mu$H로서 이론치의 약 85%~87%인 인덕턴스 효율을 나타내었고, 도전체의 교류저항은 주파수가 증가할수록 증가하여 스위칭파수 120 kHz에서 1차/2차 코일의 교류저항이 각각 3.9 $\Omega$, 0.16 $\Omega$이었고, 성능지수는 각각 158, 75로 나타났으며, 결합인자 k값은 스위칭 주파수 120 kHz에서 0.96~0.97 범위의 값을 나타내었다. 또한 자성체의 평면부분의 두께가 1.4mm까지는 인덕턴스가 평면두께가 증가할수록 큰 폭으로 증가하였고, 1.4mm이상의 두께에서는 거의 일정한 값을 나타내어 자성체의 임계 평면두께는 1.4mm로 나타났다. 그리고 70V의 입력 전압에 대하여 안정한 구형파의 출력 파형을 나타내었다.

• Archives of Reconstructive Microsurgery
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• 제20권1호
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• pp.8-13
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• 2011

Purpose: A palatal defect following maxillectomy can cause multiple problems like the rhinolalia, leakage of foods into the nasal cavity, and hypernasality. Use of a prosthetic is the preferred method for obturating a palate defect, but for rehabilitating palatal function, prosthetics have many shortcomings. In a small defect, local flap is a useful method, however, the size of flap which can be elevated is limited. In 12 cases of palatomaxillary defect, we used various microvascular free flaps in reconstructing the palate and obtained good functional results. Method: Between 1990 and 2004, 12 patients underwent free flap operation after head and neck cancer ablation, and were reviewed retrospectively. Among the 12 free flaps, 6 were latissimus dorsi myocutaneous flaps, 3 rectus abdominis myocutaneous flaps, and 3 radial forearm flaps. Result: All microvascular flap surgery was successful. Mean follow up time was 8 months and after the follow up time all patients reported satisfactory speech and swallowing. Wound dehiscence was observed in 4 cases, ptosis was in 1 case and fistula was in 1 case, however, rhinolalia, leakage of food, or swallowing difficultly was not reported in the 12 cases. Conclusion: We used various microvascular flaps for palatomaxillary reconstruction. For 3-dimensional flap needs, we used the latissimus dorsi myocutaneous flap to obtain enough volume for filling the defect. Two-dimensional flaps were designed with latissimus dorsi myocutaneous flap, rectus abdominis flap and radial forearm flap. For cases with palatal defect only, we used the radial forearm flap. In palatomaxillary reconstruction, we can choose various free flap techniques according to the number of skin paddles and flap volume needed.

• Archives of Plastic Surgery
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• 제33권3호
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• pp.383-387
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• 2006

Atypical fibroxanthoma is a pleomorphic spindle cell neoplasm characterized by a variable combination of cells with fibroblastic and histiocytic features. It occurs mostly on sun-exposed area of the head and neck of elderly person and is a clinically benign reactive lesion despite apparent malignant histologic features. However, because of its potential for metastasis, it is widely regarded as a low-grade sarcoma. We report a 30-year-old woman with atypical fibroxanthoma developed on the left occipital area. The lesion was $1.5{\times}2cm$ sized papule. There was no skin lesion such as ulcer or eschar. However, mass was involving occipital bone and composed of dense, pleomorphic spindle cells and several bizarre multinucleated giant cells. After wide excision of the scalp and occipital bone, the defect was covered with bone cement, bipedicled local flap and the donor site was covered with STSG. The wound healed completely without complication. It remained free of recurrence for a period of about 1 year follow up.

• Archives of Plastic Surgery
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• 제40권6호
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• pp.666-675
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• 2013

Background Stem cells are a unique cell population characterized by self-renewal and cellular differentiation capabilities. These characteristics, among other traits, make them an attractive option for regenerative treatments of tissues defects and for aesthetic procedures in plastic surgery. As research regarding the isolation, culture and behavior of stem cells has progressed, stem cells, particularly adult stem cells, have shown promising results in both translational and clinical applications. Methods The purpose of this review is to evaluate the applications of stem cells in the plastic surgery literature, with particular focus on the advances and limitations of current stem cell therapies. Different key areas amenable to stem cell therapy are addressed in the literature review; these include regeneration of soft tissue, bone, cartilage, and peripheral nerves, as well as wound healing and skin aging. Results The reviewed studies demonstrate promising results, with favorable outcomes and minimal complications in the cited cases. In particular, adipose tissue derived stem cell (ADSC) transplants appear to provide effective treatment options for bony and soft tissue defects, and non-healing wounds. ADSCs have also been shown to be useful in aesthetic surgery. Conclusions Further studies involving both the basic and clinical science aspects of stem cell therapies are warranted. In particular, the mechanism of action of stem cells, their interactions with the surrounding microenvironment and their long-term fate require further elucidation. Larger randomized trials are also necessary to demonstrate the continued safety of transplanted stem cells as well as the efficacy of cellular therapies in comparison to the current standards of care.

• Archives of Plastic Surgery
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• 제40권6호
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• pp.705-710
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• 2013

Background Mammalian bite injuries create a public health problem because of their frequency, potential severity, and increasing number. Some researchers have performed fragmentary analyses of bite wounds caused by certain mammalian species. However, little practical information is available concerning serious mammalian bite wounds that require hospitalization and intensive wound management. Therefore, the purpose of this study was to perform a general review of serious mammalian bite wounds. Methods We performed a retrospective review of the medical charts of 68 patients who were referred to our plastic surgery department for the treatment of bite wounds between January 2003 and October 2012. The cases were analyzed according to the species, patient demographics, environmental factors, injury characteristics, and clinical course. Results Among the 68 cases of mammalian bite injury, 58 (85%) were caused by dogs, 8 by humans, and 2 by cats. Most of those bitten by a human and both of those bitten by cats were male. Only one-third of all the patients were children or adolescents. The most frequent site of injury was the face, with 40 cases, followed by the hand, with 16 cases. Of the 68 patients, 7 were treated with secondary intention healing. Sixty-one patients underwent delayed procedures, including delayed direct closure, skin graft, composite graft, and local flap. Conclusions Based on overall findings from our review of the 68 cases of mammalian bites, we suggest practical guidelines for the management of mammalian bite injuries, which could be useful in the treatment of serious mammalian bite wounds.

• 지역사회간호학회지
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• 제15권2호
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• pp.209-217
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• 2004

Purpose: The purpose of this study was to construct the structure, process and outcome of community-based home care nursing service and to examine their validity. Method: There were two steps. The first step was developing the structure and process of community-based home care and the second was evaluating the outcome of community-based home care. Home care services were provided to 25 clients who had health problems. Data on these clients were analyzed. Result: According to Albrecht Model, in the developed structure and process of community-based home care, structure contained facility's philosophy, organization, delivery system, steering committee, office, equipments, medical instruments, the home care nurse and client of home care nursing. Process contained classification of client. nursing diagnosis and nursing intervention. The majority of clients were men (56%). The service was used mostly by people aged over 50 (82%). The most frequent nursing diagnoses were altered urinary elimination (23.2%). impaired skin integrity (21.8%) and risk for infection (17.6%). Nursing interventions included wound care (16.7%), tube care (15.1%) and catheter care (14.5%). Conclusion: Several strategies are suggested from this study: first, activate a referral system within the national health care system: second, increase public information on home care nursing: third, develop home care nursing services for elderly people: and fourth, construct a cooperation system between home care services and social welfare services.

• 대한두개안면성형외과학회지
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• 제19권1호
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• pp.13-19
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• 2018

Background: $Abb{\acute{e}}$ flap technique is one of the most challenging operations to correct horizontal deficiencies in secondary cleft lip deformity. Since its first introduction, the operative method was dynamically modified from simple variation to complete conceptual change, but conventional $Abb{\acute{e}}$ flap has many drawbacks in esthetic and functional aspect. Our purpose was reconstructing the symmetry of Cupid's bow and central vermilion tubercle with minimal sequalae. Methods: From 2008 to 2016, this technique was applied to 16 secondary cleft lip patients who had total or more than 60% of unilateral deficiency of Cupid's bow and central lip or tubercle pouting deficiency. A quadrangular-shaped flap was transferred from vermilion including skin and white line of central or contralateral lower lip. Pedicle division and insetting were made at 9 (unilateral) or 10 (bilateral) days after transfer. Secondary lip revision was done with open rhinoplasty after wound maturation. Results: Overall satisfaction was high with modified technique. Scar was minimally noticeable on both upper and lower lip especially. Balanced Cupid's bow and symmetric vermilion tubercle were made with relatively small size of flap compared to conventional $Abb{\acute{e}}$ flap. An accompanying benefit was reduced ectropion of lower lip, which made balanced upper and lower lip protrusion with more favorable profile. Conclusion: A new modified $Abb{\acute{e}}$ flap technique showed great satisfaction. It is worth considering in secondary cleft lip patient who has central lip shortage and asymmetry of upper lip vermilion border line. Our technique is one of the substitutes for correction of horizontal and central lip deficiency with asymmetric Cupid's bow.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권5호
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• pp.431-437
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• 2005

Fibrin glue is composed of fibrinogen and thrombin and used in various regions for multiple use. Basic principle is that thrombin converts fibrinogen to fibrin in the presence of $Ca^{2+}$. The structure of fibrin is loose at the beginning, but after about 5 minutes a tight structure is formed under the influence of factor VIII which changes fibrin monomer into fibrin polymer. Fibrin glue is used for tissue adhesive, suture, local hemostasis, wound healing, closure of subdural space. Fibrin adhesive has been used in oral and maxillofacial surgery for hemostasis after tooth extraction in patients with coagulation disorders, skin graft fixation, reattachment of periodontal flaps, in combination with autogenous bone chips to fill the bony cavities following cyst removal, and for securing the hydroxyapatite granules for maxillary alveolar ridge augmentation. This study was designed for researching influence of fibrin glue during healing phase after making artificial bone defect.

• 멤브레인
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• 제8권1호
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• pp.29-41
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• 1998

수용상 MPD(m-phenylene diamine)와 유기상 TMC(trimesoyl chloride)를 사용하여 역삼투 복합막의 활성층 고분자인 aromatic polyamide 제조를 행하고 그 성능을 고찰하였다. 또한 polysulfone 다공성 지지막 위에 박막을 회분, 연속식으로 계면중합 제조한 후, 제조변수에 따른 역삼투 성능을 비교하였다. 회분식으로 복합막을 제조한 결과 유기상 용매의 종류, 단량체의 농도와 함침시간, 열처리 온도, 중화제, 알코올 후처리, 산 후처리 등에 의해 다양한 성능을 나타내었다. 이때, 투과량 향상에는 알코올 후처리 효과가, 또 선택도의 향상에는 단량체의 농도와 함침시간이 변수이었다. 최적조건에서 연속식 공정으로 막모듈을 제조하여 NaCl 5,000 ppm, $25kg_f/cm^2$에서 상용막과 비교할때, 투과량은 33% 증가하고 배제율은 5% 감소하였다.

• 대한족부족관절학회지
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• 제15권2호
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• pp.79-85
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• 2011

Purpose: The purpose of the present study was to compare and analyze the clinical outcomes of the percutaneous and open repair of acute Achilles tendon ruptures. Materials and Methods: We performed a retrospective study on 24 patients (group 1) managed with percutaneous repair, and 21 patients (group 2) managed with open repair for acute Achilles tendon rupture. The postoperative evaluations were done by an Arner-Lindholm scale and AOFAS score. Postoperative overall satisfaction and cosmetic satisfaction were also evaluated. Results: By Arner-Lindholm scale and AOFAS score, there was no difference between two groups (p<0.05). As for postoperative overall satisfaction, 5 cases were very satisfied, 16 cases were satisfied and 3 cases were fair in group 1. In group 2, 12 cases were very satisfied, 9 cases were satisfied. For postoperative cosmetic satisfaction, 13 cases were satisfied, 11 cases were fair in group 1. In group 2, 9 cases were very satisfied, 12 cases satisfied. In open repair group, a case of deep wound infection and three cases of skin necrosis were reported as complication. 2 cases of sural nerve injury were seen in percutaneous repair group and were recovered within 3 months. Conclusion: Percutaneous repair of acute Achilles tendon ruptures have high level of cosmetic satisfaction compared with open repair without any significant difference in clinical outcomes.