단분자층내의 표면광산(1)

정성택,Berg,John C 한국화학공학회 1972 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.10 No.4

Experimental data on surface diffusion coefficients are obtained for monolayers of myristic, pentadecylic, palmitic, stearic and oleic acids formed on 0.01N HCl aqueous substrates at 22.3℃ using a radioactive tracer technique. Each of these acids is studied at various monolayer concentrations with reference to surface pressure-area isotherms.

폴리이미드 막의 기체투과특성에 미치는 플라즈마 처리의 영향

정성택,남세종,박노춘,김태욱 한국화학공학회 1997 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.35 No.1

합성하여 제조한 6FDA-p-TeMPD 폴리이미드 막표면에 Ar및 CF₄플라즈마 처리와 C₃F_6 플라즈마 중합 처리하여 기체투과 특성에 미치는 초기압력, 방전전력, 기체유속과 처리시간의 영향을 조사하고 기체 선택성이 최고가 되는 조건을 찾았다. XPS 스펙트라에 의하면 Ar 플라즈마는 폴리이미드의 탄소 일부를 ablation시키고 불소를 재배치 가교시키는 것으로 판단되었다. 플라즈마 초기압력 0.12 torr, 방전전력 100W, 유속 4.7sccm, 처리시간 10분의 조건에서 산소 투과계수 67barrer에 산소/질소의 최고 선택도 4.2를 얻을 수 있었다. CF₄의 경우 플라즈마 조건이 기체투과에 미치는 영향은 Ar플라즈마의 경우와 비슷하나 Ar 플라즈마만큼 선택도를 증가시킬 수 없었다. C₃F_6 플라즈마 중합처리의 경우에는 방전전력과 단량체의 유속이 선택도에 가장 민감한 영향을 끼쳤다. 플라즈마 조작 조건으로 초기압력 0.12 torr. 방전전력 60W, 단량체 유속 2.5 sccm에서 10분간 처리하였을 때 산소 투과계수 50 barrer에 최고 산소/질소 선택도 5.0에 도달할 수 있었다. The surface of 6FDA-p-TeMPD polyimide, which was synthesized by chemical imidization, was modified by plasma treatment using Ar, CF₄ and C₃F_6 . The effects of plasma conditions such as initial pressure, discharge power, gas flow rate and treatment time on gas permeation properties of the modified membrane were investigated in detail. The XPS spectra showed that the surface of the Ar plasma-treated membrane was fairly different from that of untreated membrane due to the ablation of carbon moieties and the reorientation of fluorine moieties in the polymer surface. The O₂/N₂ selectivity and the O₂ permeability were 4.2 and 67 barrer, respectively, under the conditions of 0.12 torr initial pressure, 100 W discharge power, 4.7 sccm Ar flow and 10 min treatment time. The effects of the CF₄ plasma treatment on the gas permeation properties of the membrane exhibited the similar tendency to those of Ar plasma-treated membrane. The selectivity of the CF₄ plasma-treated membrane, however, was smaller than that of Ar plasma-treated membrane. In the case of C₃F_6 plasma polymerization treatment, the O₂/N₂ selectivity and the O₂ permeability of the film were influenced mostly by discharge power and monomer flow rate, and reached 5.0 and 50 barrer, respectively, under the conditions of 0.12 torr initial pressure, 60 W discharge power, 2.5 sccm monomer flow rate and 10 min treatment time.

포상 연부 육종 - 2례 보고 -

정성택,서형연,신상규,박용철,Jung, Sung-Taek,Seo, Hyoung-Yeon,Shin, Sang-Gyoo,Park, Yong-Cheol 대한근골격종양학회 2003 대한골관절종양학회지 Vol.9 No.2

포상 연부 육종(Alveolar soft part sarcoma)은 성인에서 하지 대퇴부, 소아에서 두경부에 주로 발생한 것으로 알려져 있고, 비교적 천천히 성장함에도 불구하고 전이된 후에 발견된 경우가 많아 예후는 좋지 않은 매우 드문 종양이다. 조직학적으로 가포상(pseudoalveolar pattern)의 종양 세포들이 특징적으로 관찰되며 폐, 뇌, 골격 순으로 전이된다. 저자들은 비교적 드문 부위인 골반골에서 발생해 뇌에 전이된 1예와 하퇴부에 원발성으로 발생한 1예에 대한 치료를 경험하였기에 그 희귀성에 비추어 문헌과 함께 보고하고자 한다. As we know, alveolar soft part sarcoma is usually found at the head region in children and thigh in adults. It is very rare tumor that has poor prognosis due to its late detection after distant metastasis in spite of its slow growth rate. It is histologically characterized by pseudoalveolar pattern tumor cells. And metastasis usually occur in the site of lung, brain and skeleton in order lately. We have managed two cases of the sarcoma, one which took place in relatively rare part, pelvic bone and has spread to the brain, the other which primarily occured in the calf. For its varity, we report these two cases with reviewing of the literatures.

양성 골병변의 골결손에 사용한 수산화인회석 이식술

정성택,송은규,이재준,선종근,박용철 대한정형외과학회 골.연부조직이식학회 2003 대한골.연부 조직이식학회지 Vol.3 No.1

소아 대퇴 근위부 골절의 치료결과

정성택,이근배,윤택림,문은선,송은규 全南大醫大 2001 전남의대학술지 Vol.37 No.1

역마이셀을 이용한 α-Chymotrypsin 추출의 속도론 및 방법론

정성택,노경호,문창섭 한국화학공학회 1997 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.35 No.5

음이온성 계면활성제 AOT와 iso-octane으로 이루어진 역마이셀상을 이용하여 α-chymotrypsin을 추출하는데 있어 속도론적 및 방법론적 연구를 하였다. 단백질의 이동속도는 이중경막론에 근거한 수학적 모델을 이용하여 정량화하였다. 상간이동법에서 단백질의 순이동 속도는 이동률과 아울러 pH(<pI)와 이온세기가 낮아질수륵 증가한 반면, 그 반대 조건에서는 역이동이 우세하였다. 그러나 역이동 속도는 순이동 속도에 비해 약 10-100배 정도 느림을 보였다. 또한, 순이동의 pH조건은 역이동 속도 및 이동률에 큰 영향을 주었다. α-Chymotrypsin의 역이동을 위하여 분자체를 이용한 탈수법을 도입한 결과 pH나 이온세기의 조작 없이 단백질을 침전으로 얻어내는 것이 가능하였고 역이동에서 순이동시의 pH와 이온세기는 단백질을 침전으로 얻어내는데 영향을 주지 않았다. 그리고 분자체의 투입량이 증가할수록 회수율이 증가하였고 상간이동법에 비해 높은 값을 나타내었다. Kinetics and methodology were investigated for the extraction of a-chymotrypsin using reverse micellar phase composed of AOT and iso-octane. Experimental data on the transfer rates of protein were analyzed quantitatively by a mathematical model based on the two-film theory of mass transfer. In the case of phase transfer method, the rate and percentage of the forward transfer increased with decreasing pH(<pI) and ionic strength, while the opposite conditions favored the back extraction from the reverse micellar phase. The rates of the back extraction, however, were approximately 10 to 100 times smaller than those of the forward extraction. The forward pH condition also had a significant influence on the rate and percentage of backward transfer. In another method that was introduced for the backward transfer, the micelles were dehydrated with molecular sieves in order to precipitate protein without manipulating pH and ionic strength. The forward pH and ionic strength did not act upon the precipitation of protein and the recovery of protein was elevated with molecular sieves input and higher than in the phase transfer method

Importance of Early Follow-up Colonoscopy in Patients at High Risk for Colorectal Polyps

정성택,손대경,홍창원,김병창,박지원,한경수,장희진,최효성,오재환 대한대장항문학회 2013 Annals of Coloproctolgy Vol.29 No.6

Purpose: Minimizing the polyp miss rate during colonoscopy is important for patients at high risk for colorectal polyps. We investigated the polyp miss rate and the factors associated with it in high-risk patients. Methods: The medical records of 163 patients who underwent follow-up colonoscopy between January 2001 and April 2010, which was within 9 months after a polypectomy, because the index colonoscopy had shown multiple (more than 3) adenomas or advanced adenoma were retrospectively reviewed. Miss rates were calculated for all polyps, for neoplastic polyps and for advanced adenomas. Factors associated with the miss rates in these patients, such as the location, shape and size of the polyp, were analyzed. Results: The miss rates for polyps, adenomas, adenomas <5 mm, adenomas ≥5 mm and advanced adenomas were 32.6%, 20.9%, 17.7%, 3.2%, and 0.9%, respectively. No carcinoma, except for one small carcinoid tumor, was missed. Flat shape and small size (<5 mm) were significantly associated with adenoma miss rate. The miss rate was significantly higher for flat-type advanced adenomas than for protruded-type advanced adenomas (27.7% vs 4.1%). Conclusion: The polyp miss rate in patients at high risk for colorectal polyps was higher than expected. Efforts are needed to reduce miss rates and improve the quality of colonoscopy. Also, early follow-up colonoscopy is mandatory, especially in patients at high risk.

양성 골 종양의 절제 및 소파술 후 사용한 신선 동결 동종골 이식의 결과

정성택,배봉현,임근영,공일규,Jung, Sung-Taek,Bae, Bong-Hyun,Lim, Keun-Young,Kong, Il-Kyu 대한근골격종양학회 2005 대한골관절종양학회지 Vol.11 No.1

목적: 양성 골종양의 치료 시 발생한 공동의 골 결손에서 신선 동결 동종골 이식술을 시행한 결과에 대해 분석하고자 하였다. 대상 및 방법: 본원에서 양성 골종양으로 진단되어 종양 제거술 및 소파술 후 신선 동결 동종골 이식술을 이용한 재건술을 시행 받은 29례를 대상으로 하였다. 골 결손 부위의 크기는 술 전 단순 방사선 사진에서 병소 부위의 부피를 산출하였다. 최종 추시 상 이식된 동종골의 유합 여부 및 신생골 형성 및 재발 등을 조사하였다. 결과: 이식 골의 방사선학적 유합 소견이 관찰되기까지 소요되는 시간은 평균 11주였으며 순수하게 동종골 이식술만을 사용한 군은 11.4주, 동종골 이식술과 함께 자가골 이식술을 사용한 군은 10.7주, 동종골과 골대체물을 사용한 군은 13.6주 소요되었다. 술 전 방사선 사진상 병소의 면적이 40 $cm^3$미만인 군은 9.3주, 40 $cm^3$이상인 군에서는 12.9주에 유합 소견이 관찰되었다. 2례에서 동일 부위의 재발 소견을 보여 재수술을 시행하였으며 동종골 이식술로 인한 염증 반응 및 질환의 전파는 없었다. 결론: 저자들은 양성 골 종양의 소파술 후 신선 동결 동종골의 사용과, 동종골 및 자가골의 사용에 있어 비슷한 결과를 얻을 수 있었으며, 양성 골종양의 소파술 후 결손부위의 치료에 대해 자가골 이식이 가장 이상적인 방법으로 사료되나, 자가골 이식이 여의치 않은 소아의 경우나 골 결손부위가 커서 적절한 자가골을 얻을 수 없는 경우 등은 골 획득 및 처리가 비교적 간단하고 다양한 형태를 얻을 수 있는 신선 동결 동종골을 이용한 치료가 좋은 치료 방법의 하나로 생각된다. Purpose: We compared the time how much time spent until the bone unions, when we grafted fresh frozen allograft during therapy of benign bone tumor depends on the degrees of bony unions. Materials and Methods: This study selected 29 cases, in which a curettage on the benign bone tumors was conducted and a fresh frozen allograft was transplanted. The area of the focus, the new bone formation, the recurrence of the focus and complications in the plain radiographs were observed. Results: The average time when we could find out bony unions in the radiographs is eleven weeks. The time when we could observe the unions in the radiographs are 11.4 weeks in allograft group, 10.7 weeks in allograft and autograft groups and 13.6 weeks in allograft and bone substitute. On radiologic findings, the average lesion size is 40 cm3. The time when we could find bony unions are 9.3 weeks in less than 40 $cm^3$ and 12.9 weeks in more than 40 $cm^3$. We could observe recurrences in two cases. Conclusion: The authors could get the similar results between fresh frozen allograft, allograft and autograft after curettage of benign bone tumor. We can think the ideal method which is the transplantation of autograft, but if we can’t get autograft enough, the best way which heal the defects is the transplantation of fresh frozen allograft.

대퇴골 원위부 분쇄골절에서 시행한 이중금속판 고정술

정성택,윤택림,서형연 대한골절학회 1997 대한골절학회지 Vol.10 No.4

Supracondylar fracture of femur is not well suited to internal fixation. A wide canal, a thin cortex, comminution and compound wound make open reduction more difficult. Especially, type C2 and C3 on AO classification is problematic. The cases of nine patients who had type C2 or C3 fracture including three open fractures and deficient medial-cortical buttress were reviewed. Stable fixation was achieved with the lateral condylar buttress plate. Additional stabilization with a medial plate and bone graft from the iliac crest was applied in all nine patients. At an average duration of follow-up nineteen months (range from twelve to forty-eight months), all of the fracture had healed. Evaluation of the functional outcome revealed two excellent, three good and four fair results. In three patient, less than 90 degree of flexion of the knee was present and in six, the arc of flexion was limited to between 90 and 110 degrees. One patient had two centimeter shortening, one had medial screw loosening which need not additional fixation. The results of our study suggest that, for the treatment of patients who have a difficult fracture in whom stable fixation of the distal part of the femur cannot be achieved with a condylar buttress plate because of medial cortical communition, a short distal condylar fragment, or loss of metaphyseal bone, double-plating is indicated.

압박성 교합 골수정을 이용한 대퇴골 간부골절의 치료

정성택,윤택림,선종근 대한골절학회 1998 대한골절학회지 Vol.11 No.2

The results of treatment of femoral shaft fractures with interlocking compression nail, the third generation nail, were evaluated to determine the incidence of union of the fracture & clinical usefulness. Fifty-three femoral fractures that had been treated by interlocking compression nailing between February 1994 and March 1996 and had been followed for more than twelve months were included in this study. Forty-eight cases were fresh closed fracture and five, fresh open fracture. The results were as follows 1. According to Winquist-Hansen classification, 25 cases were type I, 13 type II, 7 type III, 5 type IV, 3 type V. 2. Union occurred in 52(97%) of 53 femoral shaft fractures. The mean fracture union period was I 8. I weeks with a range of 10 to 32 weeks. 3, Postoperative complication were delayed union(5 cases), leg length discrepancy(2 cases) and nonunion( 1 case). We concluded that interlocking compression nailing for femoral shaft fracture seems to promote the fracture healing process without conversion to dynamic intramedullary fixation.