자가 산부식 프라이머의 적용시간이 상아질의 미세인장 결합강도에 미치는 영향

조영곤,이영곤,김종욱,박병철,김종진,최희영,진철희,유상훈 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.5

This study evaluated the influence of application time of self-etching primers on microtensile bond strength (μTBS) to dentin using three self-etching primer adhesive systems. Dentin surfaces were exposed from forty-eight human molars. They were conditioned with three self-etching primers (Clearfil SE Bond [SE], Unifil Bond [UF], Tyrian SPE + One Step Plus [TY]) and different primining times (10s, 20s, 30s and 40s). Composite resins were bonded to dentin surfaces and specimens were made. μTBS was tested and statistically compared using by one-way ANOVA and Tukey's Test. The results of this study presented that priming time for 10s in SE and UF groups and for 30s and 40s in TY group was highly decreased μTBS to dentin.

단일 단계 접착제의 변연 미세누출

조영곤,정진호,기영재,최희영,진철희,유상훈,김종욱,박병철 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.2

This study evaluated the marginal microleakage of five single step adhesives. Class V cavity preparations with occlusal margins in enamel and gingival margins in dentin were prepared on both buccal and lingual surfaces of extracted human molar teeth. Prepared teeth were randomly divided into five groups and restored using one of the single step adhesives and composite resins: Prompt L-Pop/Filtek Z-250 (Group 1), AQ Bond/Metafil CX (Group 2), One-Up Bond F/Palfique Toughwell (Group 3), Futurabond/Admira (Group 4), Xeno III/Spectrum TPH (Group 5). The restored teeth were thermocycled. Microleakage was assessed by dye penetration using 2% methylene blue dye solution. The teeth were bisected buccolingually and evaluated for microleakage under steromicroscope. The data were statistically analysed by Kruskal-Wallis test and Mann-Whitney tests. The results of this study were as follows; 1. Microleakage of enamel margins in group 3 was statistically higher than that in groups 1, 2, 4, 5 (p < 0.05) 2. Microleakage of dentin margins in group 1 was statistically higher than that in groups 2, 5, and that in group 3 was statistically higher than that in groups 2, 4, 5 (p < 0.05). 3. Dentin marginal microleakage was higher than enamel marginal microleakage in all experimental groups. In conclusion, Prompt L-Pop showed the least leakage at enamel margin, and AQ Bond showed at dentin margin in this study. Marginal miroleakage in dentin was higher than that in enamel.

Anatomical distribution and detection rate of colorectal neoplasms according to age in the colonoscopic screening of a Korean population

Suk-young Lee,Wan Hee Song,Sang Cheul Oh,Byung-Wook Min,Sun Il Lee 대한외과학회 2018 Annals of Surgical Treatment and Research(ASRT) Vol.94 No.1

Purpose: Because data as a basis for the determination of proper age and modality for screening of colorectal neoplasms is lacking, we evaluated detection rates and anatomical distribution of colorectal neoplasms according to age in healthy individuals who underwent total colonoscopy for health checkup. Methods: A total of 16,100 cases that had received the colonoscopic examination from January to December in 2014 were analyzed. The total number of individuals who received total colonoscopy were divided by the number of individuals harboring colorectal adenoma to calculate the detection rate of colorectal adenoma. Individuals ≤50 years old were classified as young-age group and aged >50 were old-age group. Differences in anatomical locations of colorectal neoplasms were analyzed in the 2 age groups by chi-square test. Risk factors for colorectal adenoma in each age group were analyzed using univariate and multivariate logistic regression analyses. Results: Detection rates of colorectal adenoma were 13.7% in all cases and 12.8% for those in their 40’s. The main anatomical location of colorectal adenoma was proximal colon in both age groups (P < 0.001). Hyperplastic polyp was mainly distributed to the distal colon in both age groups (P < 0.001). Distal colon was the major site for colorectal cancer in the old-age group (P = 0.001). Proximal location of neoplasms was a risk factor for colorectal adenoma in both age groups with multivariate analysis. Conclusion: These data could be the bases for earlier initiation of screening for colorectal neoplasms with total colonoscopy to detect clinically significant colorectal polyps.

상아질에 적용된 재 습윤제가 미세인장 결합강도에 미치는 영향

강희영,조영곤,김종욱,박병철,유상훈,진철희,최희영,기영재 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.2

This study investigated that the effect of rewetting agent on dentinal microtensile bond strength (μTBS). Human molars were sectioned to expose the superficial dentin surfaces. Samples were divided into two groups according to type of adhesives-Single Bond (S) and One-Step (0)], and again subdivided into five groups by different dentin surface treatment-dry for 15s (D) , blot dry (BD) or dry for 15s, and rewet with different rewetting agents[distil1ed water (DW), Gluma Desensitizer (GD) and Aqua-Prep (AP)]for 30s. After application of adhesive, composite resin was built up on the bonding surface. Each tooth was sectioned to obtain stick with 1mm^(2) cross sectional area and the μTBS was determined by EZ test. In the S group, the mean μTBS of GD, AP and BD group was significantly higher than that of DW and D group (p < 0.05). In the 0 group, the mean μTBS of AP, GD, BD and DW group was significantly higher than that of D group (p < 0.05). The data suggested that Gluma Desensitizer and Aqua-Prep could be successfully used as rewetting agents, and Distilled water could be acceptable in aceton based adhesive system only.

Anatomical distribution and detection rate of colorectal neoplasms according to age in the colonoscopic screening of a Korean population

Lee, Suk-young,Song, Wan Hee,Oh, Sang Cheul,Min, Byung-Wook,Lee, Sun Il The Korean Surgical Society 2018 Annals of Surgical Treatment and Research(ASRT) Vol.94 No.1

<P><B>Purpose</B></P><P>Because data as a basis for the determination of proper age and modality for screening of colorectal neoplasms is lacking, we evaluated detection rates and anatomical distribution of colorectal neoplasms according to age in healthy individuals who underwent total colonoscopy for health checkup.</P><P><B>Methods</B></P><P>A total of 16,100 cases that had received the colonoscopic examination from January to December in 2014 were analyzed. The total number of individuals who received total colonoscopy were divided by the number of individuals harboring colorectal adenoma to calculate the detection rate of colorectal adenoma. Individuals ≤50 years old were classified as young-age group and aged >50 were old-age group. Differences in anatomical locations of colorectal neoplasms were analyzed in the 2 age groups by chi-square test. Risk factors for colorectal adenoma in each age group were analyzed using univariate and multivariate logistic regression analyses.</P><P><B>Results</B></P><P>Detection rates of colorectal adenoma were 13.7% in all cases and 12.8% for those in their 40′s. The main anatomical location of colorectal adenoma was proximal colon in both age groups (P < 0.001). Hyperplastic polyp was mainly distributed to the distal colon in both age groups (P < 0.001). Distal colon was the major site for colorectal cancer in the old-age group (P = 0.001). Proximal location of neoplasms was a risk factor for colorectal adenoma in both age groups with multivariate analysis.</P><P><B>Conclusion</B></P><P>These data could be the bases for earlier initiation of screening for colorectal neoplasms with total colonoscopy to detect clinically significant colorectal polyps.</P>

복합레진의 지연충전이 미세인장 결합강도에 미치는 영향

박현식,조영곤,박병철,김종욱,최희영,김종진,진철희,유상훈,기영재 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.3

The purpose of this study was to evaluate the effect of immediate or delayed composite resin filling on dentinal microtensile bond strength (μTBS) after applied the adhesive. The coronal dentin of human third molars was exposed. Single-Bond or One-Step was applied on the dentin surfaces, and composite resin were constructed immediately (group 1) or 5 min., 10 min., 15 min., 20 min. and 30 min. (groups 2-6) after an adhesive was applied. The specimens were sectioned and made bar-shaped. Each surface area of them was about l ㎟. The RBS test was performed by EZ test. The results were analysed by One-way ANOVA and Tukey's test at 95 % significance level. The results suggested that the μTBS of Single-Bond to dentin was decreased when the composite resin was constructed 20 min. and 30 min. after Single-Bond was applied. But the μTBS of One-Step was not affected by delayed composite resin filling.

법랑질 접착에 대한 습윤 효과

고근호,조영곤,진철희,유상훈,김종욱,박병철,기영재,최희영,김종진 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.3

This study evaluated the microleakage and interfacial gap between enamel and composite resin under the dry and wet condition of the enamel surface, V shaped class 5 cavities were prepared on the occlusal portion of extracted human molars. Samples were divided into three groups: D group (air dry for 10-15s), BD group (blot dry with moist cotton pellet), and DR group (air dry for 10-15s and rewet with Aqua-Prep F for 20s). Cavities were filled using Aelitefil composite resin after applied One-Step. Microleakage was tested by 2% methylene blue dye solution and the data were statistically analysed by Kruskal-Wallis test and Mann-Whitney test. Also Enamel-resin interface was observed under SEM. Group BD showed statistically lower microleakage than group D (p〈0.05). but there was no statistically significant difference between group BD and DR (p)0.05). At the enamel-resin interface, group D showed the gap of 2 ㎛ thickness, but group BD and DR showed close adaptation. In conclusion, the use of blot dry and rewetting agent (Aqua-Prep F) resulted in decreased microleakage and improved adhesion between enamel and resin when using One-Step.

기능성 소화불량증에서 증상에 따른 고형식의 반위배출시간의 차이

김영호,이풍렬,성인경,손희정,김재준,고광철,백승운,이종철,최규완 大韓消化器病學會 1998 大韓消化器病學會誌 Vol.32 No.3

Interleukin-5 저해 활성 chalcone 화합물의 유효 입체 구조

이기철,김민석,P. Thanigaimalai,Vinay K. Sharma,박경래,김영수,정상헌 충남대학교 약학대학 의약품개발연구소 2010 藥學論文集 Vol.25 No.-

Interleukin(IL)-5 appears to be one of the main proinflammatory mediators among the growing number of cytokines and chemokines that induce eosinophilic inflammation. Previously, our group synthesized a number of chalcone derivatives to determine their inhibitory activity against IL-5. However, the structure-activity relationship (SAR) of these chalcones was somewhat unclear, robably due to presence of three free rotatable bonds. To further, explore the SAR of these chalcones, we synthesized eight 2-(benzylidene)-2,3-dihydroinden-1-ones and 2- benzylidene)-3,4-dihydronaphthalen-1(2H)-ones 6 and evaluated for their inhibitory activity against IL-5. These rigidified chalcones 6 exhibited very weak inhibitory activity against IL-5 compared to chalcones 2. The structures of 6 closely resemble to the stretched conformations of chalcone 2, not effective conformation for the inhibition on IL-5 function.

[논문]직렬형 2배수 권선비 변압비를 이용한 HBML PWM 인버터

고희영,김철우 釜山大學校生産技術硏究所 2005 生産技術硏究所論文集 Vol.64 No.-

본 논문에서는 고조파를 저감하고 출력 파형을 개선하기 위하여 H-Bridge 인버터와 변압기 조합을 이용한 다중레벨 인버터를 구성함에 있어 변압기 출력 전압의 조합을 이용한 새로운 하이브리드형 멀티레벨 인버터를 제안한다. 제안한 다중 레벨 인버터는 THD을 저감하기 위해 변압기의 권션비가 1배,2배,4배인 3대를 사용하여 출력전압을 기존의 9 레벨에서 15 레벨로 증가 하였다. 또한 PWM 인버터 스위칭 패턴을 변경하여 스위칭 소자수를 10개에서 8개로 저감하고,변압기를 4개에서 3개로 저감할 수 있는 방법을 제안한다. 제안된 다중레벨 PWM 인버터의 전력회로 및 제어신호의 타당성을 입증하기 위해 프로토 타입 15레벨 언버터에 대하여 실험을 행하였다.