생체분해성 안과제형의 안구내흡수정도와 안독성

민병무,김용백,박근성,송규상,양준묵,이성복,조항진,길숙종,김승영,김학용 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

An improved retinal tack can be used to fix the retina in complicated retinal detachment and proliferative vitreoretinopathy. We used the retinal tack made by biodegradable polyglycolic acid, polylactic acid and copolymers. The tacks with polyglycolic acid were placed in the retina the right eyes of 10 rabbits as group 1, with polylactic-polyglycolic acid copolymers as group 2 in each left eyes. We examined the absorption rates and degree of intraocular inflammation at 1 day, 1, 2, 4, and 8 weeks and compared both eyes. The tacks were absorbed with time in both eyes, but more rapid in copolymers. And there was no inflammation in both eyes. Now, this study will be a base on the drug delivery system in intraocular pharmacological and surgical management.

RUS법에 의한 Micro-Crack을 가진 Ferrule의 주파수 특성 평가

백경윤,이길성,양순호,김성훈,조영재,민한기,양인영 朝鮮大學校 機械技術硏究所 2003 機械技術硏究 Vol.6 No.2

광섬유 정렬부품으로 사용되는 페롤은 극히 높은 정밀도를 요하는 제품으로서, 높은 치수 정밀도와 결함이 포함되지 않는 등 높은 신뢰성이 요구되는 제품이다. 이러한 페롤의 형상결함평가에 종래의 광학현미경 평가법과는 달리. 본 논문에서는 공명초음파법(ResonantUltrasound Spectroscopy)을 이용하고자 한다. 공명초음파법이란 결함이 없는 시험편을 기계적으로 진동시켰을 때의 공진 주파수와 시험편 내에 결함을 가지고 있을 때의 공명 주파수 양상을 비교 분석하여 결함유무를 검출해내는 방법이다. 본 연구에서는 양품과 크랙을 가진 시험편을 현장에서 직접 사용되고 있는 광학현미경에 의해 분류를 한 다음, 더욱 정확한 측정을 위해 SEM에 의해 다시 분류하였다. 각각에 대해 공진 주파수를 측정하였고, 이 데이터의 검증을 위해 FEM해석을 수행하였다. 실험으로부터 얻는 양품의 공진 주파수와 FEM해석을 통해 얻었던 양품의 공진 주파수의 오차는 1∼2%정도의 범위를 벗어나지 않음을 알 수 있었다. 또한 크랙에 대한 공진 주파수를 측정하여서, 양품의 공진 주파수와 비교를 행하였고, 이 데이터를 가지고 모드별로 히스토그램을 그려서, 그것으로부터 현장에서 실제로 이용 가능한 모드를 존재함을 확인하였다. The Ferrule which is used as the product optical fiber very precisely, is required high to set the optical axes of an dimensional precision, lack of defect and high expectation. Up to now the optical instrument has been used for the defect and shape inspection of the Ferrule, but in this paper we examined the detectable defect and expectation by using the Resonant Ultrasound Spectroscopy (RUS). The RUS is the measurement' which is to excite specimen and to inspect the difference of natural frequency pattern between acceptable specimen and specimen has some defects. In this paper, we classified specimens into three groups by using She optical instrument; acceptable specimen A-type, 3-type and specimen A-type which has crack. And we reclassified by Scanning Microscope to carry out the more exact measurement. We surveyed the resonant frequency of every specimen, and carried out the simulation from the explicit finite elements code, NasEran t o verify the experiment data. The average error between the resonant frequency of acceptable specimens which is obtained from experiment and that from FEM analysis is in the range of 1-2 percentage. Also, we measured the resonant frequency of specimen which has crack, and compared that of acceptable specimen. We drew histogram by using these data, and confirmed the available mode in the plant.

포스포닐화된 어택틱 폴리프로필레수지에 의한 금속이온의 흡착에 관한 연구

백승화,이수민,오인교 圓光大學校 1981 論文集 Vol.15 No.1

The adsorption of metal ions by chelating agent-loaded resins was studied in aqueous media. The resins were prepared by loading the conventional cation exchange resin, coated glass powder by pohsphonyl atactic polypropylene resin(200 to 250 mesh) with chelating agents containing hydroxyl groups. The composition of synthetic resins was analyzed by infrared absorption spectroscopy and also discussed. The optimum conditions for the adsorption of metal ions were determined with respect to the shaking time, the effect of cation concentration and the effect of adsorption of capacities on the industrial waste water in the medium.

직장암에서 수술 전 방사선-화학요법 후 발생한 후기 합병증

이승현,이철민,안병권,백승언 고신대학교 의과대학 2011 고신대학교 의과대학 학술지 Vol.26 No.1

OBJECTIVES: To compare the late complications after operations for rectal cancers with and without preoperative chemoradiation. METHODS: From January 2003 to December 2005, 55 patients underwent operation after preoperative chemoradiation for adenocarcinoma of the rectum. All of them received the full scheduled dose of radiation with concurrent chemotherapy. The interval between preoperative chemoradiation and surgery was 4-6 weeks. 47 patients who had tumors below 8 cm from the anal verge were enrolled into the study group (CRT group). During same period, we selected 153 patients who had adenocarcinoma of the rectum below 8cm from the anal verge, underwent surgery alone without postoperative radiotherapy non-CRT group). We compared the early and the late postoperative complications between the CRT group and the non-CRT group. RESULTS: Of the late complications, the incidence of anastomotic stricture was significantly higher in the CRT group (P = 0.018). The incidence of anal stricture was higher in the CRT group (P = 0.164). In the CRT group, 3 cases (17.6%) had failed to preserve the anal function due to moderate or severe anal stricture. Of the 3 cases, protective ileostomy was persistent in 2 cases, colostomy was performed in one case. Otherwise, the late complications of the CRT group were intestinal obstruction in 2 cases (4.3%), lymph edema in 2 cases (4.3%). CONCLUSION: In CRT group, failure of anal function preservation due to anastomotic stricture or anal stricture was more common and serious than non-CRT group. We emphasize the need for careful management for postoperative anal stricture after preoperative chemoradiation.

생체분해성 고분자를 이용한 사시수술용 제형개발 및 효용성에 대한 연구

민병무,김용백,김승영,김창식,박근성,길숙종,조항진,이성복,노승무,송규상,강대영,조준식,양준묵,정경수,최선웅,이진호,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

A new device, muscle clamping system was developed to facilitate exact quatifying technique A strabismus surgery, and reduce the risk of complications. The device is composed of a lower fixing body with three jaws and an upper supporting body. They are used to clip an extraocular muscle and fix it to the sclera with a single bite. Superior rectus recession on 16 rabbit eyes were performed with this new device. Conjunctival injection, muscle adhesion strength, and light microscopic findings were examined at 1, 2, 4 and 8 weeks postoperatively. The Conjunctival injection were minimal, adhesion power ranged from 420 to 600 gram gravity, which is sufficient in withstand the normal pull of human extraocular muscle. In microscopic exam, some Inflammatory cells and fibrosis were found. The new device was technically easy, fast, and accurate, so it may be useful in stabismus surgery.

부정교합이 성인 여자대학생의 자존감에 미치는 영향

정민호,허욱,백승학 대한치과교정학회 2008 대한치과교정학회지 Vol.38 No.6

Objective: The purpose of this study was to evaluate the effects of malocclusion on the self-esteem of female university students. Methods: The subjects were composed of 67 female university students who showed Class I molar relation, no missing or supernumerary teeth and has had no orthodontic treatment experience. Each subject was evaluated with Rosenberg's Self-esteem Scale to measure the level of self-esteem and also evaluated the degree of anterior crowding and lip protrusion through model analysis and cephalometric soft tissue profile analysis. Results: The results showed that a protrusive profile and crowding of upper anterior teeth had significant reducing effects on the level of self-esteem. The protrusion and crowding groups showed no significant differences in self-esteem between groups. Conclusions: Malocclusion had significant negative effects on the self-esteem of female university students. Further research to investigate the negative psychological influence of malocclusion and the education of lay people about this influence is necessary. 본 연구의 목적은 성장이 끝난 성인 여대생들에 있어 가장 흔한 부정교합의 하나인 전치부의 crowding과 입술주위 돌출감이 자존감(self-esteem)에 미치는 영향을 알아보는 것이다. 연구를 위하여 대학에 재학중인 여자대학생 67명을 대상으로 구강검진과 두부계측방사선 사진촬영, 모형계측을 실시하여 상악전치부의 치아배열과 입술의 돌출도를 평가하였다. 또한 Rosenberg의 자존감 평가 설문조사문항을 이용하여 이들의 자존감을 평가한 후 전치부의 치아배열, 입술주위 돌출도와 자존감 간에 어떠한 관계가 있는지 통계처리 하였다. 실험결과, 입술의 돌출을 가졌거나 전치부의 치아배열이 고르지 못한 학생들은 치아배열이 고르고 돌출되지 않은 안모를 가진 학생들에 비하여 유의하게 낮은 자존감을 보여주었다. 부정교합이 심리적으로 미치는 부정적 영향력에 관하여 더욱 체계적인 연구와 교육, 홍보가 필요하다고 생각한다.

공명초음파분광법을 이용한 광컨넥터용 결합소자의 비파괴 검사

김성훈,조영재,백경윤,양순호,민한기,양인영 朝鮮大學校 機械技術硏究所 2004 機械技術硏究 Vol.7 No.1

본 연구의 목적은 비파괴 평가방법인 공명초음파분광법(RUS)을 사용하여 세라믹제 페롤과 볼렌즈의 결함과 형상오차를 평가하는 것이다. RUS시스템은 스펙트럼에너라이저,파워 엠플리파이어,압전진동자센서와 지지프레임으로 구성되어진다. RUS 시스템에 의한 페롤과 볼렌즈의 비파괴평가를 위해 본 연구에서는 각 시험편에 대한 공진주파수를 측정하였으며,측정된 공진 주파수의 비교분석에 의해 결함의 유 · 무를 판별하였다. 그 결과 페롤의 경우,크랙을 갖는 페롤의 공진주파수 대역이 양품페롤의 공진 주파수 대역보다 고주파대역으로 이동함을 알 수 있었으며,볼렌즈의 경우,시험편 질량이 감소함에 따라 공진주파수 대역이 고주파 대역으로 이동함을 알 수 있었다. 또한 볼렌즈의 공진주파수가 측정되는 대역을 예측할 수 있는 파라메타인 β를 설정하여 그 결과를 고찰하였다. The objective of this paper is to evaluate the defect and shape error of a ceramic ferrule and ball lens by Resonant Ultrasound Spectroscopy(RUS) method. RUS system is consisted of spectrum analyzer, power amplifier, PZT sensor, and support frame. For nondestructive evaluate by using RUS system, first of all, we measured the natural frequency of each specimen, and we decided on the shape and size of flaw by measured natural ferquencies. And then, in the case of ferrule, natural frequency bandwidth of ferrule with crack was higher than acceptable ferrule. As mass of ball lens decreased, natural frequency bandwidth was shifting to high-frequency range. Thus, we discussed on the relationship between β and mass of ball lens, which β is parameter that we can predict measurable natural frequency bandwidth of ball lens.

Rat의 복강에 삽입한 Filorouracil-Polyglycolic acid제형의 Fluorouracil용출에 관한 연구

노승무,정경수,오정연,김진향,양준묵,강대영,송규상,최정목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

A common form of relapse in adenocarcinoma of the stomach is intraperitioneal dissemination, in fact, among gastric adenocarcinoma patients who have undergone surgery intended to cure, approximately 50% of the patients develope initial recurrence in the peritoneal cavity regardless of the anatomic site of the primary tumor within the stomach. The efficacy of systemic postoperative chemotherapy to prevent peritoneal recurrence of gastrric adenocarcinoma is not satisfactory. There is still a great need for improved therapeutic strategies on the disseminated microscopic disease and small miliary nodules remaining on the peritoneal surface or lymphatics after operation. The authers have made fluorouracil-polyglycolic acid composite disks(Fu-PGA disks) with fluorouracil and biodegradable polymer: polyglycolic acid for more effective intraperitoneal chemotherapy. We inserted the Fu-PGA disk(s) in the peritoneal cavity of rat and pharmacokinetic study was performed to measure fluorouracil concentration in the peritoneal fluid, plasma, liver, kidney and heart tissue at 24 hour, 72 hour and 168 hour after insertion of Fu-PGA disk(s). Myelosuppressive action of this composite also was determined following its administration. The data of this study suggested that Fu-PGA composite will be a new device releasing drugs in a controlled manner and having targetability to peritoneum, and this device will be improving the efficacy of intraperitoneal chemotherapy for gastric adenocarcinoma.

생체분해성 망막압정을 이용한 망막고정에 대한 실험적 연구

김용백,민병무,김창식,박근성,김승영,길숙종,조항진,이성복,노승무,송규상,강대영,조준식,양준묵,정경수,최선웅,이진호,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

Biodegradable retinal fixation devices obtain mechnical fixation of the retina with desirable chorioretinal scarring and with the potential for local, sustained release of antimetabolites and steroids to inhibit proliferative vitreoretinopathy. We manufactured a biodegradable retinal tack with barb that was designed in order to prevent intrusion from implantation of retinal tacks. This study was carried to evaluate the efficacy for retinal fixation and the capability for sustained release of drugs with a newly designed biodegradable retinal tack Biodegradable retinal tacks were made of polymers of glycolic acids and were designed with barbs in a shape to prevent the disinsertion. Biodegradale retinal tacks are divided into 3 parts, a conical portion that is inserted into the sclera, a cylinder portion that remains in the vitreous, and a neck portion between the pin and the cylinder. The tapered conical end was manufactured to allow easy insertion through the retina and choroid into the sclera. A cylinder portion was manufactured with a tapered angle that fixes firmly into the orifice of 19 gauge spinal needle. A neck portion, 0.4 mm in diameter, was designed to prevent disinsertion from following implantation of retinal tack. The applicator was a 19 gauge spinal needle and its orifice was prepared to 15°angle to accept the tapered cylinder portion of the retinal tack. The retinal tacks, secured in the needles, were passed through the formed vitreous and inserted into the retina, choroid, and sclera and were released by pushing the internal needle, usually within 2-3mm of the medullary ray of the posterior rabbit retina A retinal tack was placed in each of 8 pigmented rabbit eyes. Slit-lamp biomicroscopy, indirect ophthalmoscopy and fundus photography were performed periodically from 1 day to 8 weeks after surgery. Eight eyes were enucleated and studied by light microscopy at 8 weeks. Biomicroscopic evaluation of the animals revealed edemas adjacent to the retinal surfaces immediately after insertion of the biodegradable retinal tacks in all the animals. These edemas disappeared after 1 week. The first noticeable change in the size of retinal tacks was shown after 2weeks. The size of the retinal tacks gradually got smaller, decreasing to about one-half at 4 weeks and about one-third at 8 weeks. All retinal tacks remained in inserted places without any movement for an 8 week period. On light microscopy, epiretinal proliferations were seen to extend into the vitreous cavity. Cellular capsules that lined the inner aspect of the scleral defect caused by tack insertion were found. However the adjacent retina had a normal cytologic appearance and architecture in all specimens. We manufactured a biodegradable retinal tack that is designed to prevent intrusion from implantation of retinal tacks. All biodegradable retinal tacks reduce in size with time, but no retinal tacks extruded from the inserted place. The newly designed biodegradable retinal tack can be used for retinal fixation and may be used as a vehicle for the introduction of pharmacologic agents to prevent the cellular events that promote proliferative vitreoretinopathy.

Rat의 복강에 삽입한 Fluorouracil-Polyglycolic acid 제형의 Fluorouracil 용출에 관한 연구

노승무,정경수,오정연,김진향,양준묵,강대영,송규상,최정목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 忠南大學校 癌共同硏究所 1998 癌共同硏究所 硏究誌 Vol.2 No.1

A common form of relapse in adenocarcinoma of the stomach is intraperitoneal dissemination, in fact, among gastric adenocarcinoma patients who have undergone surgery intended to cure, approximately 50% of the patients develope initial recurrence in the peritoneal cavity regardless of the anatomic site of the primary tumor within the stomach. The efficacy of systemic postoperative chemotherapy to prevent peritoneal recurrence of gastrric adcnocarcinoma is not satisfactory. There is still a great need for improved therapeutic strategies on the disseminated microscopic disease and small miliary nodules remaining on the peritoneal surface or lymphatics after operation. The authers have made fluorouracil-polyglycolic acid composite disks(Fu-PGA disks) with fluorouracil and biodegradable polymer: polyglycolic acid for more effective intraperitoneal chemotherapy. We inserted the Fu-PGA disk(s) in the peritoneal cavity of rat and pharmacokinetic study was performed to measure fluorouracil concentration in the peritoneal fluid, plasma, liver, kidney and heart tissue at 24 hour, 72 hour and 168 hour after insertion of Fu-PGA disk(s). Myelosuppressive action of this composite also was determined following its administration. The data of this study suggested that Fu-PGA composite will be a new device releasing drugs in a controlled manner and having targetability to peritoneum, and this device will be improving the efficacy of intraperitoneal chemotherapy for gastric adenocarcinoma.