IgA 신병증, 미만성 반월체 사구체신염, 미소변화형 신증에서 접착분자의 발현

문경철,박소연,김활웅,이현순 대한병리학회 2000 Journal of Pathology and Translational Medicine Vol.34 No.5

용탄단조법에 의한 AC4A/SiCw 복합재료 제조에 관한 연구 (3) -기계적 특성-

문경철,이준희,윤의박 ( Kyung Cheol Moon,Jun Hee Lee,Eui Pak Yoon ) 한국열처리공학회 1994 熱處理工學會誌 Vol.7 No.3

This was studied about mechanical characteristic of AC4A/SiCw 10-30% reinforced composites. Tensile strength of pressed base metal(base metal) with SiCw preform was higher than without pressed base metal(AC4A) If SiCw whisker volume fraction was increased, tensile strength at room temperature was increased. And tensile strength of SiCw 30% was about 35㎏/㎟. Tensile strength of SiCw 30% 400℃ at same time aging was the most excellence, about 40㎏/㎟ The fracture energy value of composite material at three point bending test was higher than AC4A. Dislocation at matrix of composite material was evenly distributed. But dislocation around whisker of composite material was more existed than matrix. The reasom was thought of pile-up around whisker.

The Prognostic Implications of the Histologic Subtype and the Expression of Phosphorylated ERK 1/2 in Papillary Renal Cell Carcinoma

문경철,김보성,김동일,강태훈,신은 대한병리학회 2008 Journal of Pathology and Translational Medicine Vol.42 No.4

Background : The authors of this study wanted to confirm the prognostic implication of the histologic subtype; further, we wanted to explore the expression of phosphorylated extracellular signal-regulated kinase 1/2 (pERK) in papillary renal cell carcinoma (PRCC) and determine its clinicopathologic and prognostic significance. Methods : A total of 45 patients who underwent nephrectomy for PRCC were enrolled in this study. The hematoxylin and eosin slides were reviewed and pERK immunohistochemistry was performed. Results : Type 2 PRCC was significantly correlated with a larger tumor size (p=0.030), a higher nuclear grade (p<0.001), a more advanced tumor stage (p=0.041) and more frequent distant metastasis(p=0.019). The tumors were pERK-low (0 and 1+) in 30 cases (66.7%) and pERK-high (2+) in 15 cases (33.3%). The pERK-high PRCC was significantly associated with a smaller tumor size (p=0.001) and an earlier tumor stage (p=0.004). On the univariate analysis, the histologic subtype, the TNM stage and the pERK status were significantly associated with progression- free survival (PFS). Multivariate analysis showed that the histologic subtype (hazard ratio 22.81, p=0.042) and the TNM stage (hazard ratio 23.48, p=0.009) were independent prognostic factors for PFS. Conclusions : Type 2 PRCC, together with the TNM stage, was identified as one of independent poor prognostic factors for PFS. The pERK status was a prognostic factor for PFS on the univariate analysis, but not on the multivariate analysis.

Modified Double-Eyelid Blepharoplasty Using the Single-Knot Continuous Buried Non-Incisional Technique

문경철,윤을식,Jun-Mun Lee 대한성형외과학회 2013 Archives of Plastic Surgery Vol.40 No.4

Background Buried non-incisional double-eyelid blepharoplasty is a popular aesthetic procedure. Although various modified continuous suture techniques have been used to create a more natural appearance and to reduce downtime, complications such as loosening of the double fold, asymmetry, and foreign body reactions have been observed. Methods This study included 250 patients who underwent double-eyelid blepharoplasty between March 1997 and November 2012 using a modified single-knot continuous buried non-incisional technique. With 4 stab incisions in the upper eyelids, one of two needles loaded with double-armed 7-0 nylon was passed in one direction alternately through the dermis and the conjunctiva, while the other needle was passed subconjunctivally in the opposite direction. Both ends of the sutures were knotted within a lateral stab incision of the upper eyelids and were buried in the orbicularis oculi muscle. Results Most patients displayed satisfactory aesthetic results, and no significant complications occurred. There was no obvious regression of the double fold; however, 3 patients required reoperation to correct loosening of the fold on one side during the follow-up period. One patient presented with the suture knot subcutaneously, and the knot was removed in the clinic. Conclusions The modified single-knot continuous buried non-incisional technique is a simple and less time-consuming method for a durable double fold and provides satisfactory aesthetic results.

용탕단조법에 의한 AC4A / SiCw 복합재료의 인장특성과 미세조직

문경철,이준희 ( Kyung Cheol Moon,Jun Hee Lee ) 한국주조공학회 1994 한국주조공학회지 Vol.14 No.2

N/A Macro and micro structures by optical microscope(OM), scanning electro microscope(SEM) and transmission electro microscope(TEM) of AC4A/SiCw 10-30v/o reinforced composites were observed. Fracture mode of AC4A alloy was appeared to be plastic. But fracture mode of composites were appeared to be almost elastic. And that was occured very well with increasing of SiC whisker volume fraction. Mechanical characteristics of preformed SiC whisker reinforced composites by squeeze casting technique were more affected by squeezing pressure than temperature of molten metal. Distribution of dislocations at matrix of composites was uniform. But the number of dislocations around whisker of composites was much more than in matrix. These diffraction pattern were [011] direction for both matrix and around whisker.

Choice of recipient vessels in muscle-sparing transverse rectus abdominis myocutaneous flap breast reconstruction: A comparative study

문경철,이재민,Si-Ook Baek,Seo-Yoon Jang,Eul-Sik Yoon,이병일,Seung-Ha Park 대한성형외과학회 2019 Archives of Plastic Surgery Vol.46 No.2

Background Thoracodorsal vessels (TDVs) and internal mammary vessels (IMVs) have both been widely employed as recipient vessels for use in free muscle-sparing transverse rectus abdominis myocutaneous (MS-TRAM) flaps. However, whether TDVs or IMVs are preferable as recipient vessels for autologous breast reconstruction with a free MS-TRAM flap remains controversial. The purpose of this study was to compare the clinical outcomes when TDVs were used as recipient vessels to those obtained when IMVs were used as recipient vessels for autologous breast reconstruction with a free MS-TRAM flap. Methods A retrospective matched-cohort study was performed. We retrospectively reviewed data collected from patients who underwent a free MS-TRAM flap for autologous breast reconstructions after mastectomy between March 2003 and June 2013. After a one-to-one matching using age, 100 autologous breast reconstructions were selected in this study. Of the 100 breast reconstructions, 50 flaps were anastomosed to TDVs and 50 to IMVs. Patient demographics and clinical outcomes including operation time, length of hospital stay, postoperative complications, and aesthetic score were compared between the two groups. Results No statistically significant differences were found between the two groups in patient demographics and clinical outcomes, including the complication rates and aesthetic scores. There were no major complications such as total or partial flap loss in either group. Conclusions The results of our study demonstrate that both TDVs and IMVs were safe and efficient as recipient vessels in terms of the complication rates and aesthetic outcomes.

용탕 단조법에 의한 AC4A/Si$C_w$복합재료 제조에 관한 연구 (I)

문경철,이준희,Moon, Kyung-Cheol,Lee, Jun-Hee 한국재료학회 1992 한국재료학회지 Vol.2 No.6

최근 선진국에서 강화되고 있는 CAFE(Corporate Average Fuel Economy :기업평균연비) 규제를 극복하기 위해서는 차량의 경량화가 필수적이며 이를 위해 기존의 금속재료에 비하여 비강도, 탄성계수, 인성등이 우수한 기계적 성질을 가지면서 고분자 기지의 복합재료에 비해서 고온강도, 전기 및 열전도도와 내마모성이 우수한 금속기지 복합재료의 개발은 필수적이고도 중요한 위치를 차지한다. 따라서 본 연구에서는 자동차용 부품재 및 일반산업용 재료로 사용되고 있는 AC4A Al합금에 Si$C_w$prefohm을 용탕 단조법으로 강화하여 복합재료를 제조란 후 matrix와 함계 기계적성질, 마멸특성, 조직실험을 행한 결과 용탕 단조법에 의한 AC4A/Si$C_w$ 복합재료의 최적 제조조건은 용탕온도 80$0^{\circ}C$, 금형은도 40$0^{\circ}C$, preform은도 750-80$0^{\circ}C$, 가압압력 75MPa이었으며 Si$C_w$강화재가 I/M재에 비하여 경도값은 두배이상으로 상승하였고 Si$C_w$ 20v/o에서는 가압에 의한 큰 효과는 없었다. A fabrication process for SiC whisker preform reinforced AC4A Al composites is being developed. The Al alloy used as the matrix in this study is AC4A. SiC whisker preform made by Tokai Carbon Co. Ltd. Shizuoka, Japan were used. These consisted of $\beta$-type single crystals 0.1 ~ 10${\mu}$m in diameter and 20~10${\mu}$m in length. The most adequate fabrication condition was that whisker preform was preheated up to 750~80$0^{\circ}C$, set into a mould preheated to ~40$0^{\circ}C$, molten Al alloy heated to ~80$0^{\circ}C$ and applied pressure 75MPa. And Si$C_w$reinforced AC4A composite was advanced above twice than AC4AI/M. Also it was not large effect by pressure at Si$C_w$ 20v/o.

한국어와 일본어의 형용명사 특성으로 본 고찰

문경철 국제한국어교육학회 2017 국제한국어교육학회 학술대회논문집 Vol.2017 No.-

計裝化 샬피 시험법 에 의한 알루미늄 합금 용접부 의 동적파괴 인성

문경철,강락원,이준희 대한용접접합학회 1985 대한용접·접합학회지 Vol.3 No.2

The dynamic fracture toughness, fracture characteristics, impact tension and tensile properties of Al-Mg-Si T5 alloy and Al-Zn-Mg T6 alloy respectively welded with filler metal of Alcan 4043 were investigated. The dynamic fracture toughness values were obtained rapidly and simply for the specimen of small size by using instrumented Chirpy impact testing machine. the testing temperatures of the specimen were a range of room temperature and-196.deg. C. The results obtained in this experiment are summarized as follows. With decreasing the testing temperatures, dynamic tensile stress and fracture load were increased, on the other hand the deflection and impact value showed decreasing tendency in order of base metal>HAZ>weld. Changes of total absorbed energy were more influenced by the crack propagation energy than the crack initiation energy. At the low temperatures, the unstable rapid fracture representing the crack propagation appeared for the specimens of Charpy press side notched in Al-Zn-Mg alloy, but it was difficult to obtain the unstable rapid fracture in Al-Mg-Si alloy. Because of the development of plastic zone at the notch root, it was difficult to obtain thevalid $K_{1d}$ value in Al-Mg-Si alloy. Therefore the fatigue cracked specimens were effective in both Al-Mg-Si and Al-Zn-Mg alloys. With decreasing the impact testing temperatures, specimens underwent a transition from dimple-type transgranular fracture to lamella surface-type intergranular fracture because of the precipitate at the grain boundaries, impurities and crystal structure of the precipitates.s.

계장화 샬피시험법에 의한 Al 합금 용접부의 동적파괴 인성

문경철,이준희,강락원 대한금속재료학회 1985 대한금속재료학회 학술대회 개요집 Vol.1985 No.0