Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

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

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

Numerical analysis of flow and bed change at a confluence of the Namhan River and the Seom River using a two-dimensional model

Park Moonhyung,Kim Hyung Suk,Baek Chang Hyun 한국수자원학회 2018 한국수자원학회논문집 Vol.51 No.12

본 연구에서는 4대강 살리기 사업 후 퇴적현상이 지배적으로 발생하는 남한강과 섬강 합류부 구간을 대상으로 2차원 수치모형인 CCHE2D 모형을 이용하여 하천의 흐름 및 하상변동에 대한 해석을 수행하였다. 대상지점 합류부는 남한강 본류의 만곡부에 지류 섬강이 유입되는 특성을 갖는다. CCHE2D 모형은 비평형 유사이송을 해석하며 소류사와 부유사 조정거리가 중요한 입력변수로 대상지점에서는 소류사 조정거리가 하상변동에 가장 큰 영향을 주는 것으로 나타났다. 수치모의 결과 유량비(Qr) 변화가 남한강과 섬강 합류부 지점에서 흐름 및 하상변동에 영향을 미쳤으며, Qr≤ 2.5인 경우에는 합류전 본류의 유속이 증가하여 흐름박리구역을 감소시켰으며 이로 인해 합류부 내측의 퇴적이 감소하였다. Qr>2.5이면 합류부 구간에 퇴적이 증가하여 사주가 형성될 가능성이 높은 것으로 나타났다. 수치모의를 통해 2013년에 발생한 유량비 변화에 의해 합류부에 고정사 주가 형성된 것을 알 수 있었다. The flow and bed change were analyzed using the CCHE2D model, which is a two-dimensional numerical model, at a confluence of the Namhan River and Seom River where deposition occurs predominantly after the “Four Major Rivers Restoration Project.” The characteristic of the junction is that the tributary of Seom River joined into the curved channel of the main reach of the Namhan River. The CCHE2D model analyzes the non-equilibrium sediment transport, and the adaptation lengths for the bed load and suspended load are important variables in the model. At the target area, the adaptation length for the bed load showed the greatest influence on the river bed change. Numerical simulation results demonstrated that the discharge ratio (Qr) change affected the flow and bed change in the Namhan River and Seom river junction. When Qr ≤2.5, the flow velocity of the main reach increased before confluence, thereby reducing the flow separation zone and decreasing the deposition inside the junction. When Qr>2.5, there was a high possibility that deposition would be increased, thereby forming sand bar. Numerical simulation showed that a fixed sand bar has been formed at the junction due to the change of discharge ratio, which occurred in 2013.

근거리 무선통신용 블루투스 베이스밴드 시스템 설계 및 구현

백은창,조현묵 국립7개대학공동논문집간행위원회 2001 공업기술연구 Vol.1 No.-

In this paper, it is designed and verified the baseband system that performs various protocol functions of specification of the Bluetooth system. In order to verify the developed circuits, various baseband functions are tested by using the ModelSim simulator. The developed circuits operate at 4㎒ main clock. Test suite includes hop selection function, generation of the sync word, error correction(l/3 rate FEC, 2/3 rate FEC), HEC generation/checking, CRC generation/checking, data whitening/dewhitening and packet trans/reception procedure, etc. As a result of the simulation, it is verified that the developed baseband system conform to the specification of the Bluetooth system. Also, the developed function blocks synthesized by using the Synopsys tool. The synthesized top level circuit has 136 cells and 3,362 μ㎡ cell area. Design of Encryption and CVSD function block and implementation of FPGA chip deserve future study for better Bluetooth baseband system.

지속가능경영 우수기업의 교육훈련투자 안정성이 종업원복지와 경영성과에 미치는 영향

백평구(Baek, Pyoung-Gu),김창수(Kim, Chang-Soo),이현주(Lee, Hyun-Joo) 대한경영학회 2013 大韓經營學會誌 Vol.26 No.7

시간영역 적분방정식에 의한 도체의 산란 근접장 산출

이창현,정백호 湖西大學校 工業技術硏究所 2005 工業技術硏究所論文集 Vol.24 No.-

In this paper, we present a stable computation of the transient near-field scattered from the conducting objects. We solve the time-domain integral equation by expressing the transient behavior of the induced current in terms of weighted Laguerre polynomials. By using this basis functions for the temporal variation, the time derivative in the integral equation cam be handled analytically. Since these temporal basis functions converge to zero as time progresses, the transient response of the induced current does not have a late time oscillation. To show the validity of the proposed method, we solve a time-domain combined field integral equation and compare the results with the inverse discrete Fourier transform (IDFT) of the solution obtained in the frequency domain.

Lactobacillus casei YIT9018로부터 분리, 정제한 Whole Peptidoglycan의 In Vitro 항종양활성

金昌漢,李明燮,高時煥,朴相瑨,朴圭炫,白永振 건국대학교 생명과학연구원 1995 생명과학지 Vol.2 No.1995

공공 건설공사 중 부도에 따른 공사지연 방지 방안 : Focused on Apartment Houses

김백용,조영준,구교진,현창택 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1

The purpose of this study was to reduce the factor of construction delay in the owner's aspect by analyzing the actual condition of field supervision positively such as construction delay sample and process at the distressed company's construction site. As we analyze the examples of construction delay and reopening into various types, to minimize construction delay after the dishonor of a contractor we propose "Cooperation and reliance fixing between the contract parties through the improvement of order method, Contracting system and Construction management system".

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.

Lactobacillus casei YIT9018로부터 분리ㆍ정제한 Whole Peptidoglycan의 In Vitro 항종양활성

金昌漢,李明燮,高時煥,朴相瑨,朴圭炫,白永振 건국대학교 생명과학연구원 1995 생명과학지 Vol.2 No.-

In vitro antitumor activity of whole peptidoglycan(WPG) purified from Lactobacillus casei YIT9018 was examined by clonogenic assay. WPG had antitumor activity against five human tumor cell lines and three mouse tumor cell lines. Antitumor activity of WPG against human tumor cell lines such as A-427, SKMES-1, SF-188, FARROW and RAJI was observed at 300, 1,000, 600, 800 and 900㎍/ml concentration, respectively. Antitumor activity of WPG against mouse tumor cell lines such as 3LL, S-180 and P388 was observed at 100, 500 and 1,000㎍/ml concentration, respectively.

곡선을 포함한 임의형상의 최적자동배치에 관한 연구

이춘만,백창현 國立 昌原大學校 産業技術硏究所 1998 産技硏論文集 Vol.12 No.-

Nesting is a difficult problem which is frequently encountered in a number of industries where raw material has to be cut enconomically from a given stock part. The problem is present in industerial applications like shipbuilding, parts of a machine, clothing, manufacturing, paper or leather cutting. An algorithm for automatic nesting is proposed to obtain optimal allocation on a given part. The goal is to cut the part out of the material in such a way as to minimize the waste. Some typical nesting problems are simulated by the developed program.