• 대한치과교정학회지
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• 제24권2호
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• pp.447-476
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• 1994

This study was performed to evaluate the initial reaction of maxillofacial complex to the Class II intermaxillary and the anterior vertical elastic forces on the six types of archwires including multiloop edgewise arch wires(MEAW). A human dry skull was used for this purpose and this investigation was done by holographic interferometry. Based on such investigation, the fringe pattern and the number of fringes of each condition were compared and analyzed. The findings of this study were as follows: 1. As the orthodontic forces increased, the amount of displacement increased. 2. As the orthodontic forces were applied, the fringes were shown not only in the teeth and the maxilla but also in the adjacent bones, i.e., temporal bone, zygomatic bone, nasal bone, frontal bone and sphenoid bone. And the direction of fringe pattern and the number of fringes were different from each other by the sutures. 3. As the long Class II elastic forces were applied, the backward-downward displacements of the anterior teeth and the maxilla were shown, and backward displacement of the former were grater than those of the latter. And backward displacements were greater by the long Class II elastic forces than by the short Class II elastic forces. 4. As the anterior vertical elastic forces were applied, downward displacements of the anterior teeth and the maxilla were shown, and the downward displacements of the former were greater than those of the latter relatively. 5. The downward displacements of the anterior area to the anterior vertical elastic forces of the MEAW were greater than those of other archwires. In addition, the more tip-back bend was applied, the more displacement was seen. 6. As the Class II intermaxillary forces and the enough anterior vertical elastic forces were applied on the MEAW with tip-back bend, there was an intrusive effect of the posterior teeth.

• 한국전산구조공학회논문집
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• 제22권6호
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• pp.533-539
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• 2009

본 연구에서는 먼저 완전 신전상태의 병변이 없는 26세 남자의 자기공명영상이미지를 기반으로 대퇴골, 경골, 관절연골, 반월상 연골의 정밀한 3차원 재구축을 실시하였다. 재구축된 무릎모델에 인대와 건을 생리학적으로 적합한 위치에 부착시켜 3차원 유한요소모델을 완성시켰다. 뼈, 관절연골, 반월상 연골은 균질성, 등방성 선형탄성거동을 보이는 것으로 고려하였으며, 인대와 건은 트러스 요소와 선형, 비선형 스프링 요소를 사용하여 모델링하였다. 제작된 무릎관절의 유한요소모델을 ABAQUS를 사용하여 비선형 접촉해석을 수행하였다. 수치해석결과로서 조직의 손상과 환자의 통증을 추정하기 위한 중요매개변수로 간주될 수 있는 관절연골과 반월상연골의 접촉압력과 von Mises 응력분포를 계산하였으며, 관절연골과 반월상 연골의 접촉압력과 von Mises 응력분포를 분석하여 무릎관절에 대한 파손평가를 실시하였다.

• 대한골관절종양학회지
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• 제4권1호
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• pp.30-36
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• 1998

Squamous cell carcinoma is a neglected disease entity in orthopedic oncology. The purpose of this study was to analyze overall survival and the role of surgery on survival and to evaluate the significance of possible prognostic factors. From Oct, 1986 to Aug, 1996, 57 patients were enlisted and 42 patients ere eligible. Inclusion criteria included more than one year follow-up and no distant metastasis at the first visit. Staging and survival followed AJC classification and Kaplan-Meier plot. Stage II included 17 cases and stage III, 25 cases. Thirty-eight patients underwent operations, chemotherapy, and/or radiotherapy, and the remaining four had operations only. The chemotherapeutic regimen was adriamycin-cisplatin. The average follow-up period was 45 months. The ten-year actuarial survival rate of whole patients was 65.4%. Location of primary lesion, stage, pathologic grading, and intensity of chemotherapy in the same stage showed a significant difference in survival. Nine out of 42 patients had local recurrence. Seven patients had inadequate wide margins and two had intralesional margins. Average period of recurrence from operation was 13(4-35)months. The operation itself had no impact on survival but a surgical margin of no less than 3cm from the lesion was important for local control. Pathological grade and staging were significant variables for long term survival. Acral lesion had a significantly higher chance of regional and distant metastasis but actual survival showed no difference. In stage II, aggressive chemotherapy could delay or reduce the chance of regional or distant metastasis.

• 대한환경공학회지
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• 제31권1호
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• pp.70-78
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• 2009

지형도를 이용하여 전국 주요하천의 홍수터 면적을 조사하였고, 원판형 부압침투계를 이용하여 홍수터 토양의 투수특성을 조사하였다. 문헌조사와 불포화 흐름해석용 코드를 이용하여 홍수터에서 도시하수의 2차 처리수에 대한 토양처리의 가능성도 평가하였다. 이들 자료를 바탕으로 우리나라의 홍수터여과 용량을 산정하였다. 연구결과 우리나라의 홍수터는 토양여과에 적합한 표층토를 가지며, 하천연장 전체에 걸쳐 홍수터가 골고루 분포되어 있어서 홍수터여과가 하수의 추가처리로 활용되기에 유리한 여건임을 알 수 있었다. 우리나라 전체의 홍수터여과 용량은 약 182,000,000 $m^3$/day이고, 대부분의 하천들은 2차 처리수를 모두 홍수터여과를 통해 추가적으로 처리할 수 있을 것으로 계산되어 이 공법을 적용할 경우 하천수질이 개선 될 것이라고 기대한다. 또한, 본 공법은 상수원수의 수질개선에도 활용될 수 있을 것으로 기대되었다.

• 한국전기전자재료학회논문지
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• 제24권3호
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• pp.188-193
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• 2011

The osseointegration of dental implant is influenced by many factors such as surface geometry, loading and the amount of bone. Thus, stability of the dental implant should be checked periodically. In order to test the stability of dental implant by using resonance frequency analysis, we designed a structure of transducers and fabricated a piezoelectric devices. Using finite element analysis, the thickness and length of piezoelectric device and transducers were tailorized and the optimized frequency of 10 kHz was obtained. The resonance frequency from simulation analysis and evaluation was estimated to be similar as 10 kHz. The osseointegration was further enhanced with increasing frequency from the evaluation result of the finite element analysis.

• 한국정밀공학회지
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• 제25권5호
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• pp.148-154
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• 2008

Pharmacotherapy was mainly used to treat osteoporosis. However, some researches showed that pharmacotherapy could induce unexpected adverse effects. Some studies showed that whole body vibration affected beneficially osteoporosis. This paper studied the effect of whole body vibration fur osteoporosis compared with the effect of pharmacotherapy. 10 female rats were used and allocated into 4 group, CON, SHAM, DRUG, and WBV. Rats except SHAM group were ovariectomised to induce osteoporosis. Rats in WBV group were stimulated in whole body vibration at magnitude of $1mm_{peak-peak}$ and frequency 45Hz, for 8 weeks (30 min/day, 5 days/week). Rat in DRGU group was orally administered the Actonel (0.58mg/Kg), for 8 weeks (5days/week). The $4^{th}$ lumbar in rats were scanned at a resolution of $35{\mu}m$ at baseline, before stimulation, and 8 weeks after stimulation by In-vivo micro computed tomography. For detecting and tracking changes of biomechanical characteristics (morphological and mechanical characteristics) in lumbar trabecuar bone of rats, structural parameters were measured and calculated from acquiring images and finite element analysis was performed. In the results, loss of quantity and change of structure of trabecular bone in WBV group were smaller than those in both CON and SHAM groups. In addition, mechanical strength in WBV group was stronger than that in both CON and SHAM groups. In contrast, biomechanical characteristics in WBV group were similar with those in DRUG group. These results showed that reasonable whole body vibration was likely to treat osteoporosis and be substituted partly for drug treatment.

• 한국자원식물학회지
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• 제23권2호
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• pp.138-144
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• 2010

최근 한약추출박은 배출되는 양이 많아 쓰레기화 되어 환경을 크게 오염시키고 있다. 이러한 한약추출박을 퇴비로 재활용하기 위한 기초시험으로 첩약(貼藥)인 '연령고본단(延齡固本丹)'의 한약추출박 성분을 분석하였고, 여기에 배초향을 재배하여 비료로 시용한 후 생육특성과 전초 수량을 조사한 결과는 다음과 같다. 1. 한약추출박의 분석 성분 중 유기물은 89.6%가 함유되어 있었고, 염분은 0.1%로 약초의 생장에 지장이 없는 공정규격(1.0%)이하의 범위였다. 약초의 생장에 직접적으로 필요한 비료 3요소 중 질소는 2.8%가 함유되어 있었고, 인산은 0.6%, 그리고 칼륨은 0.5%가 함유되어 있었다. 미량성분으로 식물체의 영양분이 될 수 있는 성분은 아연과 구리 등이 함유되어있었다. 이러한 분석결과, 한약추출박 성분은 유기물과 질소, 인산, 가리, 미량요소 등이 골고루 함유되어 유기질 비료로 사용 될 수 있을 것으로 본다. 2. 한약추출박의 시용에 따른 배초향의 생육은 한약추출박 시용이 무시용보다 초장과 경직경이 크고, 엽수와 가지수가 많아 생장이 양호 하였고, 수량도 전초 1주중이 무거워 증수되는 경향이었다. 한약추출박의 시용농도는 30~50 g의 시용에서 효과가 인정되었으므로 추출박 30 g의 농도가 적정 시용 농도로 판단된다. 이상의 결과를 종합하여 볼 때 한약추출박은 배초향과 같은 전초이용 약초에 유기질 비료로 재활용 할 수 있을 것으로 본다.

• 대한의용생체공학회:의공학회지
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• 제43권1호
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• pp.61-70
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• 2022

Natural and synthetic forms of calcium phosphate cement (CPC) have been widely used in bone repair and augmentation. The major challenge of injectable CPC is to deliver the cells without cell death in order to regenerate new bone. The study objective was to investigate for the potential of stem cell-laden gelatin fibers containing injectable, nanocrystalline CPC to function as a delivery system. Gelatin noddle fiber method was developed to delivered cells into nCPC. Experimental groups were prepared by mixing cells with nCPC, mixing cell-laden gelatin fibers with nCPC and mixing cell-laden gelatin fibers containing BMP-2 with nCPC. Media diffusion test was conducted after dissolving the gelatin fibers. SEM examined the generated channels and delivered cell morphology. Fibers mixed with nCPC showed physical setting and hardening within 20 min after injection and showed good shape maintenances. The gelatin fibers mixed nCPC group had several vacant channels generated from the dissolved gelatin. Particularly, proliferation and attachment of the cells were observed inside of the channels. While live cells were not observed in the cell mixed nCPC group, cells delivered with the gelatin fibers into the nCPC showed good viability and increased DNA content with culture. Cell-laden gelatin fiber was a novel method for cell delivery into nCPC without cell damages. Results also indicated the osteogenic differentiation of gelatin fiber delivered cells. We suggest that the cell-laden gelatin fibers mixed with nCPC can be used as an injectable cell delivery vehicle and the addition of BMP-2 to enhances osteogenesis.

• 대한본초학회지
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• 제32권2호
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• pp.41-47
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• 2017

Objective : The aim of this study is to investigate anti-arthritis activity using a korea's natural monument No. 265 designate 'Yeonsan-Ogye'. In this study, research by using extracts from different concentration of the Yeonsan-Ogye through an MIA-induced arthritis animal model was being conducted in vivo and scientifically verifying the efficacy of medicinal food. Methods : Yeonsan-Ogye was administered 500 mg/kg/day, 1000 mg/kg/day, 2000 mg/kg/day to SD-Rat, where arthritis was induced by monosodium iodoacetate (MIA) at $60mg/m{\ell}$. MMP-9, COMP, CTXII, calcitonin and glycosaminoglycan level in serum were measured by ELISA. The changes of relative hind paw weight bearing ratio by Incapacitance Test Meter and The cartilage of meniscus volume was examined and 3-D high-resolution reconstructions of the cartilage of meniscus were obtained using a Micro-CT system. Also, the histopathological analysis of knee was observed by H&E and safranin-O staining. Results : Production of MMP-9, COMP (all groups) and CTXII (500, 1000 mg/kg/day) level in serum was decreased, respectively, in comparison with control. The other way, production of calcitonin (500, 1000 mg/kg/day) and glycosaminoglycan (all groups) level in serum, Hind paw weight bearing ratio (all groups) was increased, espectively, in comparison with control. The cartilage of patella volume in micro-CT increased significantly. In addition, all groups showed a increase in the cartilage volume and proteoglycan. Conclusion : The results for Yeonsan-Ogye showed significant antiarthritis activity in serum and the cartilage. Therefore, it is thought to be that Yeonsan Ogye can be utilized as a variety of new korea medicie and health foods against arthritis diseases.

• 대한한방소아과학회지
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• 제37권4호
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• pp.1-14
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• 2023

Objectives This study aimed to evaluate the correlation between pediatric weakness scale scores and growth indices. Furthermore, we intended to calculate the cut-off values for diagnosing Kidney Weak Children through growth indices. Methods A total of 193 patients, aged 6 - 12 years, underwent both the pediatric weakness scale and bone age assessment, and the correlations between the pediatric weakness scale and growth indices were analyzed. Moreover, the cut-off values for diagnosing Kidney Weak Children were calculated. Differences in bone age and predicted height between the normal group and Kidney Weak Children, classified according to the calculated cut-off values, were analyzed. Results The weakness of the Shin or kidney system was significantly correlated with the height percentile, weight percentile, differences in current height percentile and mid parental height percentile, differences in predicted height and mid parental height, and differences in bone age and chronological age. When the criteria for diagnosing Kidney Weak Children is set at "height percentile of ≤25% and weight percentile of ≤25%", the sensitivity and specificity of the cut-off value were maximized. The cut-off values for weakness of the Shin or kidney system were 9 in children aged 6 - 9 years and 10 in children aged 10 - 12 years. Conclusions To diagnose Kidney Weak Children, the cut-off values of weakness of the Shin or kidney system were 9 in children aged 6 - 9 years and 10 in children aged 10 - 12 years.