• 치과방사선
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• 제24권2호
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• pp.279-290
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• 1994

The purpose of this study was to compare the diagnostic accuracy of periapical radiographs and their digitized images for the detection of simulated interproximal carious lesions. A total of 240 interproximal surfaces was used in this study. The case sample was composed of 80 anterior teeth, 80 bicuspids and 80 molars which were prepared in order to distribute the surfaces from carious free to those containing simulated carious lesions of varying depths (0.5㎜, 0.8㎜, and 1.2㎜). The periapical radiographs were taken by paralleling technique and film used was Kodak Ektaspeed(E group). All radiographs were evaluated by five dentist to recognize the true status of simulated carious lesion. They were asked to give a score of 0, 1, 2, or 3. Digitized images were obtained using a commercial video processor(FOTOVIX Ⅱ- XS). And the computer system was 486 DX PC with PC Vision and frame grabber. The 17' display monitor had a resolution of 1280×1024 pixels(0.26㎜ dot pitch). But the one frame of the intraoral radiograph has a resolution of 700×480 pixels and each pixel has a grey level value of 256. All the radiographs and digital images were viewed under uniform subdued lighting in the same reading room. After a week the second interpretation was performed in the same condition. The detection of lesions on the monitor was compared with the finding of simulated interproximal carious lesions on the film images. The results were as follows: 1. When the scoring criteria was dichotomous ; lesion present and not present 1) The overall sensitivity, specificity and diagnostic accuracy of periapical radiographs and their digital images showed no statistically significant difference. 2) The sensitivity and specificity according to the region of teeth and the grade of lesions showed no statistically significant difference between periapical radiographs and their digital images. 2. When estimate the grade of lesions ; score 0, 1, 2, 3 1) The overall diagnostic accuracy was 53.3% on the intraoral films and 52.9% on digital images. There was no significant difference. 2) The diagnostic accuracy according to the region of teeth showed no statistically significant difference between periapical radiographs and their digital images. 3. The degree of agreement and reliability 1) Using gamma value to show the degree of agreement, there was similarity between periapical films and digital images. 2) The reliability of each twice interpretation of periapical films and digital images showed no statistically significant difference. In all cases P value was greater than 0.05, showing that both techniques can be used to detect the incipient and moderate interproximal carious lesions with similar accuracy.

• 대한치과보철학회지
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• 제43권4호
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• pp.426-437
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• 2005

Statement of problem : Although zirconium oxide ceramics are more and more commonly used in restorative dentistry, for many clinical applications only limited data can be found in the literature. However it is quite clear that hydrofluoric acid etching is impossible with zirconia ceramics. Therefore, other bonding techniques are required in order to lute these materials adhesively. Purpose : The purpose or this study was to evaluate the effects of surface treatments on shear bond strengths between two resin cements and a zirconia ceramic. Materials and methods : Experimental industrially manufactured yttrium-oxide-partially-stabilized zirconia ceramic discs (Adens, Korea) were used for this study. The ceramic specimens divided into five experimental groups and a control group (as received). Five surface treatments were studied 1) sandblasting with 110$\mu$m $Al_2O_3$ at 3 bars pressure 13 seconds at a distance of 10 mm, 2) flame-treated with the Silano-Pen for 5 $s/cm^3$, 3) grinding with a diamond bur. 4) sandblasting + Silano-Pen treatment, 5) diamond bur preparation + Silano-Pen treatment. Acrylic plastic tube (5 mm in height and 3 mm in diameter) were filled with composite to fabricate composite cylinders The composite cylinders were bonded to the ceramic specimens with either Superbond C&B or Panavia F resin luting agents. All cemented specimens were tested under shear loading until fracture on universal testing machine at a crosshead speed 1mm/min; the maximum load at fracture was recorded. Sheat bond strength data were analyzed with oneway analysis of variance and Tukey HSD tests (P<.05). Treated ceramic surfaces and fracture surfaces after shear testing were examined morphologically using scanning electron microscope. Results: Ceramic surface treatment with Silano-Pen after sandblasting improved the bond strength of Superbond C&B resin cement. Supevbond C& B resin cement at Silano-Pen aiker sandblasting($27.4{\pm}3.8MPa$) showed statistically higher shear bond strength than the others. Conclusion: Within the limitation of this study, Superbond C& &B resin cement are suitable for cementation of zirconia ceramics and flame-treated with the Silano-Pen after sandblasting is required to enhance the bond strength.

• Journal of Korean Neurosurgical Society
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• 제54권2호
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• pp.107-111
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• 2013

Objective : We investigated the effectiveness of stereotactic gamma knife Radiosurgery (GKR) for radioresistant brain metastases with the impact upon histology. Methods : Between April 2004 and May 2011, a total of 23 patients underwent GKR for 67 metastatic brain tumors from 12 renal cell cancers, 5 sarcomas and 6 melanomas. The mean age was 56 years (range, 18 to 79 years). Most of the patients were classified as the Radiation Therapy Oncology Group recursive partitioning analysis class II (91.3%). The synchronous metastasis was found in 6 patients (26.1%) and metachronous metastasis in 17 patients (73.9%). We analyzed the local control rate, intracranial progression-free survival (PFS) and overall survival (OS). Results : The mean tumor volume for GKR was 2.24 cc and the mean prescription dose was 19.4 Gy (range, 10 to 24) to the tumor margin. Out of metachronous metastases, the median duration to intracranial metastasis was 3.3 years in renal cell cancer (RCC), 2.4 years in melanoma and 1.1 years in sarcoma (p=0.012). The total local control rate was 89.6% during the mean 12.4 months follow-up. The six-month and one-year local control rate was 90.2% and 83% respectively. Depending on the pathology, the control rate of RCC was 95.7%, sarcoma 91.3% and melanoma 80.5% during the follow-up. The common cause of local failure was the tumor bleeding in melanoma. The median PFS and OS were 5.2 and 8.4 months in RCC patients, 6.5 and 9.8 months in sarcoma, and 3.8 and 5.1 months in melanoma. Conclusion : The GKR can be one of the effective management options for the intracranial metastatic tumors from the radioresistant tumors. The melanoma showed a poor local control rate compared to other pathologies because of the hemorrhage.

• 한국진공학회지
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• 제17권1호
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• pp.67-72
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• 2008

본 연구에서는 염료감응 태양전지의 상대전극으로써 다중벽 탄소나노튜브를 사용하여 전기화학적 특성에 미치는 열처리 효과에 대해 연구하였다. 다중벽 탄소나노튜브는 실리콘 기판위에 철 촉매를 사용하여 열화학 기상증착법으로 합성하였다. 직경이 다른 다중벽 탄소나노튜브를 각각 성장하여 두 개의 샘플을 준비하였고 질소 분위기의 RTA(rapid thermal annealing) system에서 $900^{\circ}C$ 온도로 1분간 열처리 하였다. 다중벽 탄소나노튜브의 구조적, 전기적, 전기화학적 특성은 FE-SEM, Raman spectroscopy, 2-point probe station, electrochemical impedance spectroscopy (EIS)을 이용하여 측정하였다. 라만 스펙트럼 분석에서 열처리 한 다중벽 탄소나노튜브의 I(D)/I(G) ratio는 상당히 감소한 것을 확인하였으며, 다중벽 탄소나 노튜브 표면과 전해질과의 산화 환원 반응 특성에서는 열처리 전보다 열처리 후의 전해질과의 산화 환원 반응 특성이 향상된 것을 알 수 있었다. 표면에서의 반응 저항 또한 열처리 후의 다중벽 탄소나노튜브가 더 낮은 값을 나타내었다. 그 결과, 열처리 후의 다중벽 탄소나노튜브를 상대전극으로 사용하였을 때의 전기화학적 특성이 더 좋은 것을 확인하였다.

• 한국산학기술학회논문지
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• 제20권12호
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• pp.747-757
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• 2019

본 연구는 노인환자가 인식하는 간호사와의 상호작용을 측정하기 위해 개발된 the Korean version of Nurse-Patient Interaction Scale (K-NPIS)을 한국 요양병원에 입원한 노인환자를 대상으로 간호사와의 상호작용을 측정의 신뢰도와 타당도를 검증하려는 목적으로 시행되었다. 진주시, 순천시, 남원시에 소재하는 4개의 요양병원에 입원한 노인환자 202명을 대상으로 신뢰도와 타당도 검증을 실시하였다. 문항분석과 내적일관성 검증을 통해 K-NPIS의 Cronbach α 값은 .96이었다. 전문가들을 통한 내용타당도 검증에서 내용타당도 지수가 0.8 이상으로 확인되었으며, 확인적 요인분석을 거쳐 최종 단일속성으로 구성된 12개 문항 각 10점 척도의 최종 도구가 도출되었으며, 재원기간에 따라 K-NPIS의 점수가 유의하게 차이가 나(p=.042) 판별타당도도 검증되었고, 천장효과나 바닥효과는 나타나지 않았다. 이와 같이 K-NPIS는 신뢰도와 타당도가 높은 도구임이 검증되어 요양병원에서 노인환자를 대상으로 간호사-환자의 상호작용을 측정하는 도구로 사용되는데 적절한 것으로 보이나 장차 준거타당도를 검증할 필요가 있다. K-NPIS는 노인환자가 인식하고 있는 간호사와의 상호작용을 자가보고 형식으로 측정하는 것이므로, 노인환자와의 상호작용을 기반으로 한 돌봄 중재의 성과를 평가하여 간호서비스 질 향상에 기여할 수 있을 것으로 기대된다.

• Restorative Dentistry and Endodontics
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• 제15권2호
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• pp.77-92
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• 1990

The purpose of this study was to evaluate the cytotoxic effects of 6 cavity liners in vitro. Human fibroblasts were cultured in ${\alpha}$-MEM and each liner was manually mixed and filled in glass ring cylinder ($8{\times}8mm$ in diameter, in height). The cylinders filled with the liners were placed in the center of the dish (35mm in diameter) containing 3ml of ${\alpha}$-MEM. Millipore filters (pore size $0.22{\mu}m$) to simulate dentin barrier were also placed between the bottom of cylinder and the dish. Then the culture dishes were stored in 5% $CO_2$ containing incubator for 5 and 10 days at the temperature of $36.6^{\circ}C$. The results of the experiments were analyzed by counting the cells in the period of 5 and 10 days respectively, and were assessed by calculating the cell multiplication rate and the relative growth rate. The experiemntal groups and the control group were compared statistically. The results of the study were summarized as follows: 1. The cell number of Zinc oxide-eugenol was $(4.13{\pm}1.31){\times}10^4$ cells/ml at 5 days and $(4.32{\pm}1.61){\times}10^4$ cells/ml at 10 days. 2. The cell number of Cavitec was ($8.35{\pm}2.87{\times}10^4$ cells/ml and $(10.08{\pm}5.10){\times}10^4$ cells/ml at 5 and 10 days respectively. 3. The cell number of Dycal was $(13.56{\pm}3.89){\times}10^4$ cells/ml at 5 days and $(34.75{\pm}8.85){\times}10^4$ cells/ml at 10 days. 4. The cell number of life was $(11.46{\pm}3.32){\times}10^4$ cells/ml and $(21.92{\pm}6.18){\times}10^4$ cells/ml at 5 and 10 days. 5. The cell number of Base cement was $(13.73{\pm}3.73){\times}10^4$ cells/ml and $(36.68{\pm}5.20){\times}10^4$ cells/ml at 5 and 10 days. 6. The cell number of Dentin cement was $(13.58{\pm}3.90){\times}10$ cells/ml and $(66.95{\pm}24.09){\times}10$ cells/ml at 5 and 10 days. 7. The cell multiplication rate of zinc oxide-eugenol cements was significantly less than that of the calcium hydroxide and glass ionomer cement. (P < 0.05)

• 한국식품영양과학회지
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• 제32권7호
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• pp.1147-1152
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• 2003

본 연구는 경남 남해군 서면과 설천면에 거주하는 85세 이상의 고령 노인 중에서 거동에 불편함이 없고 특별한 질환이 없는 대체로 건강한 노인 100명을 대상으로 하였다. 대상자들의 일반적인 특성, 식습관 및 건강관련 요인들을 조사한 결과는 다음과 같다. 교육수준은 무학이 95.0%로서 남자는 83.3%, 여자는 98.7%를 나타내었고 가족형태는 아들과 함께 사는 경우가 63.0%로 가장 많았으며 딸과 함께 사는 경우가 1.3%로 가장 적었다. 월 평균 용돈은 5만원 이하가 51.7%로 가장 많았고 81.0%의 노인들이 자녀에게 용돈을 받는 것으로 나타났다. 부모님의 사망연령은 아버지가 평균 67.3$\pm$15.9세, 어머니가 평균 58.1$\pm$16.6세로 거의 유사하였으나 남자 노인인 경우는 아버지가 여자노인인 경우는 어머니가 더 오래 생존했던 것으로 나타났다. 하루에 세 끼니를 섭취하는 노인이 평균 84.0%로 가장 많았는데 여자(89.5%)가 남자(66.7%)에 비해 유의적으로 많았으며(p<0.05)남녀 각각 91.7%, 93.4%의 노인이 규칙적인 식습관을 갖고 있었다. 조사 노인의 약 77.1%가 금기식품이 없다고 하였고 약 90.5%가 건강식품이나 보충제를 섭취하지 않고 있었다. 음주는 남자 58.3%, 여자 35.5%가 하는 것으로 나타났고 음주시작 연령은 남자는 30세 이전이 71.4%로 가장 많았으며 여자는 31∼40세가 33.3%로 가장 많았고 일일 평균 알코올 섭취량은 남자는 11∼30g, 여자는 10g이하가 대부분이었다. 남자 33.3%, 여자 28.9%가 흡연을 하였으며 흡연시작 연령은 남자는 20세 이전, 여자는 31∼40세가 가장 많았고 흡연량에 있어서는 하루 5개비 이하가 남녀 각각 37.5%, 50.0%로 가장 높은 비율을 차지하였다. 조사 노인들의 평균 수면시간은 6∼8시 간, 활동시간은 4∼5시간이 가장 많았고 남자 91.7% 여자 85.5%가 ‘건강하다’, 남자 58.3% 여자 67.1%가 ‘행복하다’라고 스스로 인식하고 있었다.

• 한국산림과학회지
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• 제95권3호
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• pp.323-327
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• 2006

국내 주요 경제수종인 소나무의 내성 가계와 민감성 가계간의 오존에 대한 피해반응 및 내성반응을 알아보고자 본 연구를 수행하였다. 내성 가계와 민감성 가계를 각각 5가계씩 선발하여 오존 100 ppb 농도에서 90일간 처리를 하여 근원경 생장, SOD 활성, MDA 함량을 측정하였다. 근원경 생장에서 오존 처리 초기에 내성 가계가 민감성 가계에 비하여 약 3배 높은 생장율을 보였으며, 처리 기간 동안 내성 가계의 생장이 더 우수한 것으로 나타났다. 대조구에 대한 처리구의 SOD 활성비는 민감성 가계의 경우 오존 처리 초기에 증가하고 처리 기간이 길어짐에 따라서 지속적으로 감소한 반면, 내성 가계는 60일까지 증가한 후 감소하였다. 오존 처리구의 MDA 함량은 대조구에 비하여 전체적으로 높게 나타났으며, 민감성 가계가 내성 가계보다 높은 MDA 함량을 나타냈다. 따라서 내성 가계는 민감성 가계에 비하여 항산화 능력이 우수하기 때문에 지질과산화 작용을 억제하는 등 생리적 장애를 극복하는 능력이 높아 생장감소가 적게 나타나는 것으로 판단된다.

• 유통과학연구
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• 제11권4호
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• pp.51-60
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• 2013

Purpose - The objective of this paper is to investigate the effect of asset specificity, the level of information sharing, the importance of information sharing, and an integrated collaborative environment on supply chain performance. Research design, data, and methodology - Data collection was implemented as follows: questionnaires were distributed to 250 companies that have business ties with Halla Climate Control Corporation. The empirical study to test our hypothesis was based on statistical analysis (using SPSS 18.0 and AMOS 18.0). The hypothesis of this paper is that the asset specificity variable has positive effects on the following variables: Level of information sharing, the importance of information sharing, and integrated collaborative environment. Moreover the variables, the level of information sharing, and the importance of information sharing are strongly influenced by the variable integrated collaborative environment, and these when combined, have an effect on the dependent variable, supply chain performance. We tested our hypothesized model utilizing path analysis with latent variables. Results - According to the results of our analysis, hypothesis H1, which tests whether there is a relationship between asset specificity and the integrated collaborative environment, is supported at the 0.01 level. Hypotheses H2 and H3 were also confirmed, and asset specificity had positive effects (+) on the level of information sharing variable. The importance of the information sharing variable was statistically significant at the 0.01 level. Hypotheses H4 and H5 posited that the integrated collaborative environment variable would have a positive effect on the level of information sharing; the importance of information sharing variable was strongly supported statistically, with a significant p-value below. Moreover, the level of information sharing (H6), and the importance of information sharing (H7) variables also had a statistically relevant influence on supply chain performance. As a result, existence of a collaborative system between companies would influence supply chain performance by strengthening real-time information access and information sharing. Thus, it is important to construct a collaborative environment where information sharing among companies and cooperation is possible. Conclusions - First, with rapid changes in the business environment, it becomes necessary for enterprises to acquire the right information in order to properly implement SCM. For successful SCM, firms should understand the importance of collaboration with supply chain partners and an internally built collaboration system, which in turn will better promote a partnership commitment with suppliers as well as collaborative integration with buyers. A collaborative system, as we suggest in this paper, facilitates the maintenance of a long-term relationship of trust, and can help reinforce information sharing. Second, it is necessary to increase information sharing over time via a collaborative system so that employees of the suppliers become aware of the system. The more proactive and positive attitudes are towards such a collaborative system by the managerial group, the higher the level of information sharing will be among the users. Successful SCM performance is achieved by information sharing through a collaborative environment rather than by investing only in setting up an information system.

• Journal of Periodontal and Implant Science
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• 제35권1호
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• pp.99-109
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• 2005

It has been focused on the importance of the host inflammatory response in periodontal pathogenesis and progression, treatment has been introduced to control the host response and the method, which diminishes production and activity of MMP by doxycycline, has been used in periodontal field. MMP is a proteolytic enzyme which plays a major role in tissue destruction and MMP-1 is secreted in the periodontally healthy tissue, while MMP-8, 9, 13, etc in the inflammatory state. Among these, MMP-13 has been discovered lately and reported to degrade primarily type II collagen. Periodontal ligament (PDL) cell plays a role in destruction of periodontal tissue. This study was to evaluate the effect of doxycycline and mefenamic acid, non-steroidal antiinflammatory drug on MMP-13 mRNA expression in the rat PDL cell. Doxycycline concentration of $1{\sim}100\;{\mu}g/ml$ was added rat PDL cell and cell activity was measured by MIT assay at day 1 and 3. MMP-13 gene expression was evaluated by RT-PCR after PDL cells were pre-treated for 1hour with doxycycline (50 ${\mu}g/ml$) alone or with mefenamic acid ($10^{-6}M$), then added $IL-1{\beta}$(1.0 ng/ml) and incubated for 16-18 hours. The results are as follows: 1. Cell activity decreased Significantly at 24 and 72 hours in 100 ${\mu}g/ml$ (p<0.05). 2. Level of MMP-13 mRNA was in 20.2% increase by $IL-1{\beta}$ and in pre-treating doxycycline group, expression of $IL-1{\beta}$ induced MMP-13 mRNA was inhibited by 31% than $IL-1{\beta}$ treated only. 3. Mefenamic acid did not inhibit on the expression of $IL-1{\beta}$ induced MMP-13 mRNA, while mefenamic acid in combination with doxycycline inhibited the expression by 41% compared to only $IL-1{\beta}$ stimulation. These results suggest that doxycycline synergistically inhibit the expression of $IL-1{\beta}$ induced MMP-13 mRNA in combination with mefenamic acid.