• 한국방사선학회논문지
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• 제14권6호
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• pp.841-848
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• 2020

광자선과 전자선을 사용하는 방사선 치료 분야에서는 환자마다 방사선에 대한 민감도가 다르기 때문에 동일한 선량에서도 피부 부작용이 발생될 수 있다. 이에 피부에 과다선량 위험도가 있을 경우, 선량계를 부착하여 정확한 선량이 조사되고 있는지 검증하고 있다. 하지만 피부선량계는 점선량을 측정하는 방식으로 부착부위를 육안으로 확인하기 때문에, 정확한 선량 분포를 확인하기 어려운 문제점이 있다. 이에 본 연구에서는 체표면적에 대한 선량분포를 확인할 수 있는 2D 선량계의 기초 연구로 감약률 오차를 분석하여 최적화된 선량계 조건을 제시하고자 하였다. 본 결과 6 MV 광자선에서 물질 HgI₂의 측정과 시뮬레이션 오차는 최소두께 25 ㎛에서 각 각 3.73%, 5.24%를 보였고, 물질 PbI₂는 각각 4.73%, 5.65%를 보였다. 반면 6 MeV 전자선 결과, 물질 HgI₂의 측정과 시뮬레이션 오차는 최소두께 25 ㎛에서 각 각 1.35%, 1.12%를 보였고, 물질 PbI₂는 각 각 1.67%, 1.20%로 비교적 낮은 감약률 오차를 보였다. 이에 본 연구 결과 5% 이내의 감약률 오차를 가지기 위해서는 광자선 측정은 최소 25 ㎛ 미만, 전자선 측정은 100 ㎛ 이내 두께가 적합한 것으로 평가되었다. 본 연구는 임상에서 요구되는 인체 부착형 flexible 선량계의 새로운 연구 방향과 미래 피부선량계의 구성 조건을 제시하고 있다.

• Journal of Periodontal and Implant Science
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• 제26권1호
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• pp.1-26
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• 1996

This study was performed to estimate the effects of cultured bone cell inoculated on porous type hydroxyaptite for the regeneration of the artificial alveolar bone defect. In this experiment 3 beagle dogs were used, and each of them were divided into right and left mandible. Every surgical intervention were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium(30mg/Kg). To reduce the gingival bleeding during surgery, operative site was injected with Lidocaine hydrochloride(l:80,000 Epinephrine) as local anesthesia. After surgery experimental animal were feeded with soft dietl Mighty dog, Frisies Co., U.S.A.) for 1 weeks to avoid irritaion to soft tissue by food. 2 months before surgery both side of mandibular 1st premolar were extracted and bone chips from mandibular body were obtained from all animals. Bone cells were cultured from bone chips obtained from mandible with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. Porous type hydroxyapatite were immerse into the high concentrated cell suspension solution, and put 4 hours for attachin the cells on the surface of hydroxyapatite. Graft material were inserted on the artificial bone defect after 3 days of culture. Before insertion of cellinoculated graft material, scanning electronic microscopic observation were performed to confirm the attachment and spreading of cell on the hydroxyapatite surface. 3 artificial bone defects were made with bone trephine drill on the both side of mandible of the experimental animal. First defect was designed without insertion of graft material as negative control, second was filled with porous replamineform hydroxyapatite inoculated with cultured bone marrow cells as expermiental site, and third was filled with graft materials only as positive control. The size of every artificial bone defect was 3mm in diameter and 3mm in depth. After the every surgical intervention of animals, oral hygiene program were performed with 1.0% chlorhexidine digluconate. All of the animals were sacrificed at 2, 4, 6 weeks after surgery. For obtaining histological section, tissus were fixed in 10% Buffered formalin and decalcified with Planko - Rycho Solution for 72hr. Tissue embeding was performed in paraffin and cut parallel to the surface of mandibular body. Section in 8um thickness of tissue was done and stained with Hematoxylin - Eosin. All the specimens were observed under the light microscopy. The following results were obtained : 1. In the case of control site which has no graft material, less inflammatory cell infiltration and rapid new bone forming tendency were revealed compared with experimental groups. But bone surface were observed depression pattern on defect area because of soft tissue invasion into the artificial bone defect during the experimental period. 2. In the porous hydroxyapatite only group, inflammatory cell infiltration was prominet and dense connective tissue were encapsulated around grafted materials. osteoblastic activity in the early stage after surgery was low to compared with grafted with bone cells. 3. In the case of porous hydroxyapatite inoculated with bone cell, less inflammatory cell infiltration and rapid new bone formation activity was revealed than hydroxyapatite only group. Active new bone formation were observed in the early stage of control group. 4. The origin of new bone forming was revealed not from the center of defected area but from the surface of preexisting bony wall on every specimen. 5. In this experiment, osteoclastic cell was not found around grafted materials, and fibrovascular invasion into regions with no noticeable foreign body reaction. Conclusively, the cultured bone cell inoculated onto the porous hydroxyapatite may have an important role of regeneration of artificial bone defects of alveolar bone.

• 한국식품위생안전성학회지
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• 제28권3호
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• pp.272-278
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• 2013

본 연구는 polyvinyl chroride (PVC)와 stainless steel 표면에서 E. coli O157:H7의 부착, 바이오필름형성, 온 습도에 따른 생존율을 조사하고, E. coli O157:H7이 오염된 작업대 표면에서 상추로의 교차오염도 조사를 통하여 E. coli O157:H7에 오염된 작업대가 상추의 미생물학적 안전성에 미치는 영향을 평가하고자 수행하였다. 작업대 표면 재질인 PVC와 stainless steel에 E. coli O157:H7 배양액을 1시간 노출시켰을 때, PVC의 경우, stainless steel 보다 10배 정도 부착력이 높았으나, 6시간째는 두 재질간의 차이가 없었다. 또한, E. coli O157:H7의 바이오필름 형성은 TSB > 10% 상추추출액 > 1% 상추추출액 > phosphate buffer 순이었으며, 재질별로는 PVC에서 바이오필름형성능이 높은 것으로 나타났다. 온도 $20^{\circ}C$, $30^{\circ}C$, 습도 43%, 69%, 100%에서 각각 노출 시켰을 때, E. coli O157:H7은 온도 $30^{\circ}C$, 습도 43%, 69% 조건에서 12시간 내에 약 5.0 log CFU/coupon이 감소한데 반해, 상대습도 100%에서는 농도의 큰 변화 없이 5일 이상 생존이 지속되었다. 또한, 유기물이 작업대 표면에 존재 시, E. coli O157:H7의 감소 속도가 느렸다. E. coli O157:H7에 오염된 작업대에 상추를 접촉시키고 상추의 오염도를 조사한 결과, 상추 표면에 수분이 존재할 때 오염된 작업대 표면에서 E. coli O157:H7의 이동수준이 상추에 수분이 없을 때 보다 10배 이상 증가하는 것으로 나타났다. 따라서 E. coli O157:H7에 오염된 작업대는 상추의 안전성에 직접적인 영향을 미칠 수 있어 작업 후에 세척, 소독을 통하여 위생적으로 관리하는 것이 필요하다.

• Journal of Periodontal and Implant Science
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• 제25권3호
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• pp.741-755
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• 1995

구강내 매식된 임프란트가 과도한 교합력이나 염증등의 이유로 구강내로 노출되었을 때 세균독소에 이완된 면을 제거하고 평활한 면을 형성하여 주위의 연조직, 경조직에 적합한 상태로 만들어 건강한 상태로 구강내에 유지하기 위해서 임프란트 매식체 표면을 기계적인 표면처리방법으로 처치하여 이러한 방법이 임프란트 표면성분, 치은섬유아세포의 전개양상에 미치는 영향을 알아보고자 본 실험을 실행하였다. IMZ사에서 제작한 직경 10mm, 높이 2mm의 원판 타이타늄을 이용하여 피막되지 않은 타이타늄면과 TPS면을 대조군으로 하고 기계적인 표면처리방법인 low speed stone bur처치면을 실험군으로 설정한 후 EDX로 타이타늄 표면성분을 분석하였고 주사전자현미경으로 치은섬유아세포의 전개양상을 관찰하였다. EDX에 의한 타이타늄 표면성분분석 결과 모든 실험군에서 titanium peak, 소량의 aluminum이 나타났으며 그외의 성분은 나타나지 않았다. 치은섬유아세포의 전개양상에 대한 주사전자현미경 관찰결과 평활한 타이타늄면에서 접종 30분 후 세사상돌기와 박판엽상으로 확장된 세포가 많이 관찰되며 6시간 후 신장된 치은섬유아세포가 시편에 밀착된 양상을 보였고 24시간 후 치은섬유아세포는 시편의 모든 면을 피개하며 가공시의 평행한 선을 따라 방향성을 띄었다. TPS가 잔존한 stone처치군에서 세포 접종 30분 후 세사상돌기가 적게 관찰되어 평활한 타이타늄면에 비해 초기부착이 늦은 것을 알 수 있었고 6, 24시간후 치은섬유아세포는 거친면으로 인해 시편에 밀착되지 못한 양상을 보였으나 평활한 타이타늄면과 연결되며 시편의 모든면을 피개하였다. TPS군에서 치은섬유아세포는 세포 접종 30분후 세사상돌기를 거의 찾아 볼 수 없어 초기부착이 다른군에 비해 늦으며 세포배양 6, 24시간후에도 시편에 밀착되지 못하고 박판상돌기가 가늘고 길게 돌출되어 여러면에 부착된 양상을 보였으며 세포가 부착되지 않은 TPS면이 관찰되었다.

• 대한환경공학회지
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• 제30권3호
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• pp.271-277
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• 2008

난분해성물질 함유폐수에 대해 유지관리가 용이하며 저비용-저에너지 고효율적인 새로운 수 처리 방식인 대기노출형 백색부후균 생물막 공법을 적용하기 위한 기초실험을 실시하였다. 먼저 난분해성물질을 함유한 오 폐수 처리에 가장 효율적인 백색부후균 종을 선정하기 위해 백색부후균 3종 및 활성슬러지에 대한 처리특성을 조사하였으며, 선정된 백색부후균 P. chrysosporium PSBL-1에 대해서 HBC링 여재에 대한 부착 및 탈착특성을 조사하였다. 백색부후균 3종(P. chrysosporium PSBL-1, P. chrysosporium KCTC 6147, Trametes sp. KFCC 10941)의 pH에 따른 처리특성을 조사한 결과 NBDCOD 제거율은 P. chrysosporium PSBL-1과 P. chrysosporium 6147가 pH 3.5$\sim$5.5에서 각각 51$\sim$59.8%, 57.5$\sim$60.3%로 비슷한 결과를 나타냈으나, TN 제거율은 pH 4.5$\sim$11.5에서 각각 39.3$\sim$85.3%, 3.4$\sim$7.6%로 현저한 차이를 나타내고 있다. 유기물 및 질소 동시제거 특성을 고려하여 백색부후균 P. chrysosporium PSBL-1을 선정하였다. 백색부후균 P. chrysosporium PSBL-1은 부유상태의 초기농도 4,600 mg/L에서 HBC링 여재 부착시작 5분후 pH 4, 7, 10에서 각각 4,538 mg/L, 4,546 mg/L, 4,531 mg/L, 10분 후 4,575 mg/L, 4,573 mg/L, 4,568 mg/L로 5분 이후에는 미생물 부착이 거의 되지 않았다. HBC링 여재에 부착된 P. chrysosporium PSBL-1을 10일 동안 1일 간격으로 탈착량을 조사한 결과 탈착량은 거의 미미하였다.

• Journal of Periodontal and Implant Science
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• 제38권2호
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• pp.237-246
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• 2008

Purpose: If bone grafts and guided tissue regeneration are effective individually in treating osseous defects, then the questionis, what would happen when they are combined. Bone grafts using Calcium Carbonate(Biocoral) and Guided Tissue Regeneration using Calcium Sulfate(CALMATRIX) will maximize their advantages and show the best clinical results in intrabony defects. This study was to compare the effects of a combination of CS and CC with control treated only with modified widman flap in a periodontal repair of intrabony defects. Materials and Methods: 30 patients with chronic periodontitis were used in this study. 10 patients were treated with a combination of CS and CC as the experimental group II and another 10 patients were treated with CC as the experimental group I, and the remaining 10 patients, the control group were treated only with modified widman flap. Clinical parameters including probing depth, gingival recession, bone probing depth and loss of attachment were recorded 6 months later. Results: The probing depth changes were $3.30{\pm}1.34\;mm$ in the control group, $4.2{\pm}1.55\;mm$ in the experimental group I(CC) and $5.00{\pm}1.33\;mm$ in the experimental group II(CS+CC). They all showed a significant decrease 6 months after surgery(p<0.01). There was a significant difference(p<0.05) between the control and experimental group. However there were no significant difference(p<0.05) between the experimental group I and II. The gingival recession changes w $-1.30{\pm}1.25\;mm$ in the control group, This is a significant difference(p<0.01). However, there was a $-0.50{\pm}0.53\;mm$ change in the experimental group I(CC) and $-0.60{\pm}0.97\;mm$ in the experimental group II(CS+CC). In addition, in terms of gingival recession, there was a no significance difference(p<0.05) among the groups. The clinical attachment level changes were $2.00{\pm}1.33\;mm$ in the control group, $3.60{\pm}1.58\;mm$ in the experimental group I(CC) and $4.40{\pm}1.17\;mm$ in the experimental group II(CS+CC). They all showed a significant decrease 6 months after surgery(p<0.01). There was a significant difference(p<0.05) between the control and experimental group. However there was a no significance difference(p<0.05) between the experimental group I and II. The bone probing depth changes were $0.60{\pm}0.52\;mm$ in the control group, $3.20{\pm}1.48\;mm$ in the experimental group I(CC) and $4.60{\pm}1.43\;mm$ in the experimental group II(CS+CC). All of them showed a significant decrease 6 months after surgery(p<0.01), there was a significance difference(p<0.05) among the groups. Conclusion: Treatment using a combination of CS and CC have a potential to improve periodontal parameters in intrabony defects and More efficient clinical results can be expected in intrabony defects less than 2 walls grafted with CS and CC.

• 대한간호학회지
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• 제24권2호
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• pp.264-277
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• 1994

In Korea the concept of social support was first used as a research concept in nursing and has not had much application in the clinical field. Another problem is that research on social support has used a direct translation of the words “social support” into Korean as “sawhejuk jiji”. Three questions were posed to direct the re-search. 1) Is there a concept of social support in Korean society? 2) if so, what words or expressions are used to de-scribe it? 3) further, if so, how is social support structured and how does it function? In order to answer the research questions a three-step research methodology was used : The first step consisted of a literature review on re-search related to social support and on information on the background of, and the way of thinking re-lated to interpersonal relations among Korean people. The second step, which was done to identify whether there is a concept of social support in korean society, involved interviewing a sample of the population. The third step involved a panel discussion that included the members of the research team and three consultants, a sociologist, a philosopher and a scholor in korean literature. A review of the literature on interpersonal relationships in traditional korean society identified a four cirole structure that explains interpersonal relationships. The first circle with “me” at the center is the family but here “me” disappears into the “we” that is essential for a cooperative agricultural society. In the second circle are those close to “me” but outside the family. The third circle includes those with whom “I ” have infrequent but regular contact and with whom correct conduct is important. The last circle is all the people with whom “I” have nothing in common. They are excluded in interpersonal relationships. The literature on interpersonal relationships showed that within the traditional Korean society people lived in villages where most people were very familiar with each other. “Yun”, the social network established the connection and “Jung”, the feeling of affection increased with time as the connection was strengthened. In the traditional village psychological support was provided through “Mallaniki”, “Pumashi” and “Kae” with the latter two also providing material support. In modern Korea there are more informal and formal social networks, like social services and community activities on the formal level and cultural and leisure groups along with “kae’s on the informal level. But even with this modern variety of groups, most social support comes from informal networks that resemble the traditiorlal “Pumashi”, “Kai” md “Mallaniki”. The six member research team interviewed 65 people in order to identify whether there is a concept of social support and then analysed their responses. There were 20 different words describing the reception of the social support and these could be grouped into seven major categories : virtuous, fortunate, helped, supported, blessed, attached(receiving affection) and receiving (grace) benevolence. there were 27 words describing the act of social support which could be categorized into seven major categories : love, looking after, affection(attachment), kindness(goodness), faith, psychological help and material help. for the meaning of social support translated as “sawhe juk jiji” there were a total of 14 different answers which could be categorized into 3 major categories : help, agreement, and faith. In third step, the results of the literature review and the answers to the questions were discussed in a pannel. The results of the discussion led to the following definition of social support in Korea which is shaped like a the four sided pyramid on a base. Social support is the apex of the pyramid and four sides are made up of : “do-oom” (both emotional and material help), “jung” (connectedness, or relationship bound by affection, regard or shared common experience ), “midum” (faith or belief in), “eunhae” (kindness or benevolence). The research team identified “Yun”( the basic network of relationships) as the base of the pyramid and as such the foundation for the components of social support in Korean culture. On “Yun” rest the other four components of social support : “Jung”, “Midum”, “Do-oom”, and “Eunhae”, For social support to take place there must be “Yun”. This is an important factor in social support. In private social network “Jung” is an essential factor in social support. But not in the public social network. “Yun” is a condition for “Jung” and “Jung” is the manifestation of support.

• 대한치과보철학회지
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• 제43권3호
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• pp.363-378
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• 2005

Statement of problem. Hydroxyapatite(HA) coated titanium surfaces have not yet showed the reliable osseointegration in various conditions. Purpose. This study was aimed to investigate microstructures, chemical composition, and surface roughness of the surface coated by the hydrothermal method and to evaluate the effect of hydrothermal coating on the cell attachment, as well as cell proliferation. Material and Methods. Commercially pure(c.p.) titanium discs were used as substrates. The HA coating on c.p. titanium discs by hydrothermal method was performed in 0.12M HCl solution mixed with HA(group I) and 0.1M NaOH solution mixed with HA(group II). GroupⅠ was heated at 180 $^{\circ}C$ for 24, 48, and 72 hours. GroupⅡ was heated at 180 $^{\circ}C$ for 12, 24, and 36 hours. And the treated surfaces were evaluated by Scanning electron microscopy(SEM), Energy dispersive X-ray spectroscopy(EDS), X-ray photoelectron spectroscopy(XPS), X-ray diffraction method(XRD), Confocal laser scanning microscopy(CLSM). And SEM of fibroblast and 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) assay were used for cellular responses of the treated surfaces. Results. The color of surface changed in both groups after the hydrothermal process. SEM images showed that coating pattern was homogeneous in group II, while inhomogeneous in group I. H72 had rosette-like precipitates. The crystalline structure grew gradually in group II, according to extending treatment period. The long needle-like crystals were prominent in N36. Calcium(Ca) and phosphorus(P) were not detected in H24 and H48 in EDS. In all specimens of group II and H72, Ca was found. Ca and P were identified in all treated groups through the analysis of XPS, but they were amorphous. Surface roughness did not increase in both groups after hydrothermal treatment. The values of surface roughness were not significantly different between groups I and II. According to the SEM images of fibroblasts, cell attachments were oriented and spread well in both treated groups, while they were not in the control group. However, no substantial amount of difference was found between groups I and II. Conclusions. In this study during the hydrothermal process procedure, coating characteristics, including the HA precipitates, crystal growth, and crystalline phases, were more satisfactory in NaOH treated group than in HCl treated group. Still, the biological responses of the modified surface by this method were not fully understood for the two tested groups did not differ significantly. Therefore, more continuous research on the relationship between the surface features and cellular responses seems to be in need.

• Clinical and Experimental Reproductive Medicine
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• 제23권1호
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• pp.95-102
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• 1996

This study was performed to investigate the effect of human follicular fluid (HFF) on development of mouse embryos, for evaluating the suitability of HFF as a substitutive material of human fetal cord serum in ART program. The various concentrations of HFF were added into the culture medium and the effects of HFF concentrations were examined to identify the optimal concentration of HFF for embryo development. The potency of HFF in improving embryo development was compared to that of other protein supplement. Collected HFFs were classified with the maturity of the containing oocytes; mature, immature, atretic, and then the effects of the classified HFFs on embryo development were examined. Also, HFF was separated into the low (<30,000 Da) and high (>30,000 Da) molecular weight fractions and the effects of the fractions on embryo development were investigated. The highest development rate was found in culture medium supplemented with 20% HFF, bnt this rate was reversely reduced at the concentrations of HFF higher than 20%. The development rates to the blastocyst, hatching blastocyst, attachment and outgrowth cultured in mature HFF was significantly higher than those in immature and atretic HFF, and mean cell number in blastocyst was higher in mature HFF than in immature and atretic HFF. The development rates of mouse embryos according to protein sources were significantly higher in HFF than in fetal cord serum (FCS), maternal serum (MS) and bovine serum albumin (BSA), and mean cell number in blastocyst cultured in HFF was higher than that in FCS, MS and BSA. The development rates of embryo and mean cell number in blastocyst cultured in high molecular weight fraction of HFF were higher than those in low molecular weight fraction, but the results of high molecular weight fraction were lower than those of whole HFF. Therefore, these results indicated that human mature follicular fluid was useful for improving the development of mouse embryos, which suggests a possibility that HFF also may be used efficiently for improving the culture condition in human ART program as a protein supplement.

• Journal of Periodontal and Implant Science
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• 제38권4호
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• pp.657-668
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• 2008

Purpose: In this study, we compared low-power $CO_2$ laser treatment to ultrasonic scaling, which is generally approved as a power-driven mechanical instrumentation, and evaluated both of these treatments regarding their clinical effectiveness and change in the volume of in GCF. Material and methods: 20 patients who had gingivitis were selected. all of patients has no systemic problems. Randomly selected, one quadrant received ultrasonic scaling only, another quadrant received ultrasonic scaling and $CO_2$ laser irradiation, the other quadrant received $CO_2$ laser irradiation only. Clinical parameters measured at baseline, 1 weeks, 2weeks, 4weeks and 8weeks. Result: Pocket probing depth and clinical attachment level were not changed during study period. Gingival index of all group were improved after treatment. At 1 weeks after treatment, Gingival index of ultrasonic scaling group was only significantly different compared to control group. At 2 weeks after treatment, gingival index of all experimental group were significantly different compared to control group. At 4 and 8 weeks after treatment, gingival index of all group were increased, but experimental group were lower than control group. Sulcus bleeding index was similar to the results of gingival index. At 1 weeks after treatment, all experimental group were significantly different compared to control group and it maintained during study. At 2 weeks after treatment, sulcus bleeding index of all group were lowest during study. Gingival crevicular fluid were measured with $Periotron^{(R)}$ 8000($Oraflow^{(R)}$, Inc. USA). At baseline, all group were showed moderately severe condition. At 1 week after treatment, laser treatment only group was reduced quantity of gingival crevicular fluid mostly, and all group were reduced quantity of gingival crevicular fluid. At 2 weeks after treatment, all group were health state. At 4 and 8 weeks after treatment, all group were showed recurrent of inflammation, and control group was the most significantly increased. Conclusion: This study showed that the effects of $CO_2$ laser treatment were similar to conventional ultrasonic scaling and this result remained longer than plaque control only. These results suggest possibility of $CO_2$ laser treatment for altered periodontal therapy.