치료용 방사선의 입사각에 따른 광섬유 방사선량계의 체렌코프 빛 측정 및 분석

장경원,조동현,유욱재,신상훈,서정기,이봉수,박병기,문주현 제주대학교 방사선응용과학연구소 2008 방사선응용과학연구소논문집 Vol.22 No.-

In this study, we have measured scintillating light generated in a fiber-optic dosimeter by high energy photon and electron beams using a charge-coupled device. The intensity of Cerenkov lights are also measured and characterized as functions of incident angles and energies of the high energy beams from a clinical linear accelerator. To minimize or remove Cerenkov light, a simple subtraction method using a background optical fiber and wavelength discrimination method using optical filters are investigated. Also, the intensities of Cerenkov light induced by high energy photon and electron beams are compared.

매복된 하악 제2대구치 맹출유도의 치험례

한수경,김정욱,이상훈,김종철,한세현,장기택 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.1

정상적인 하악 성장에서, 하악 제1대구치 후방의 치배는 근심경사되어 있다. 보통 이러한 근심경사는 자발적으로 해소되나, 항상 그런 것만은 아니다. 첫 번째 증례는 14세 여아로서 가족이 모두 하악 제2대구치가 매복된 병력을 가지고 있었다. 환아 역시 양측 모두 매복되어 분절호선과 개방용 코일 스프링으로 치료하였다. 두 번째 증례는 14세 남아 환자로 Halterman 장치를 이용하여 매복된 하악 우측 제2대구치를 치료하였다. 세 번째 증례는 11세 남아로서 고정성 교정 치료 중, 하악 양측 제2대구치가 매복되었다. 분절호선과 개방용 코일 스프링 구리선으로 치료하였다. In the normal growth and development of the mandible, the molar tooth buds distal to the first permanent molar have a mesial inclination. This inclination is usually self-correcting, but, unfortunately this self-correction does not always occur. The first case is about, 14-year old female patient with familial history of lower second molar impaction. Hew lower second molars were both impacted, and she was treated with sectional wires and open-coil springs. The second case, 14-year-old male, we treated his impacted #47 with Halterman appliance. The third case, 11-year-old male, his both mandibular second molars were impacted during full-fixed orthodontic treatment. They were treated with brass wire sectional wire and open coil spring.

활석을 이용한 사포나이트의 수열합성

배인국,장영남,채수천,류경원,최상훈 한국광물학회 2003 광물과 암석 (J.Miner.Soc.Korea) Vol.16 No.2

삼팔면체형의 스멕타이트계 사포나이트(saponite)를 천연 광물질인 활석을 이용하여 수열법에 의해 합성하였다. 출발물질은 활석에 Na₂CO₃를 첨가하여 공기중에서 800℃로 가열한 후, 화학양론적 조성에 맞게 Al(No₃)₃·9H₂O 및 Mg(No₃)₂·6H₂O 금속염 수용액을 첨가하였고, pH는 7∼12 범위 내로 NH₄OH 수용액에 의해 조절하여 제조하였다. 수열반응 조건은 약 1리터의 수열반응 용기에서 230 ℃, 압력은 25∼75 kgf/㎠의 범위 내에서 10∼60시간이었다. 실험결과, 반응온도 및 회전속도를 230℃와 180 rpm으로 고정시킨 수열조건 하에서 반응시간, 반응압력, pH 조건을 각각 40시간, 25 kgf/㎠, 약 10으로 하였을 때, 그리고, 화학조성을 화학양론적 조성에 필요한 Na₂O의 양보다 200% 과량 추가하였을 때, 양호한 사포나이트가 합성되었다. 또한 압력을 75 kgf/㎠까지 증가시켜도 결정도에 미치는 영향은 미미하였으며, 반응시간이 길수록 더 좋은 결정도를 나타냈다. Saponite was synthesized from talc by hydrothermal method. The starting material was prepared by adding Al(N0₃)₃·9H₂0 and Mg(N₃)₂·6H₂O solution to the talc powder, which was previously activated in air at 800℃ together with Na₂C0₃. The alkalinity of the solution was controlled by NH₄0H solution. The autoclaving was carried out in the closed stainless steel vessel (about 1 liter) for 40 hours under the pressure of 25 ㎏f/㎠ at 230℃. The characterization of the reaction product shows that saponite was crystallized successfully. After the experimental results, pressure was not sensitive parameter in the range of 25-75 ㎏f/㎠, but longer reaction time results in better crystallinity.

광섬유 방사선 센서와 EBT 필름을 이용한 심부선량 백분율 측정 및 비교

조동현,장경원,유욱재,신상훈,이봉수,문주현,박병기 제주대학교 방사선응용과학연구소 2008 방사선응용과학연구소논문집 Vol.22 No.-

In this study, fiber-optic sensor is fabricated to measure PDD of CLINAC. As a scintillating light generated by a high energy X-ray from the medical LINAC is measured using photo diode amp system, It is expected that a high-resolution, real-time fiber-optic dosimeter for medical LINAC can be developed.

광섬유 집합체 센서를 이용한 6MV 광자선의 반음영 및 심부선량백분율 측정

신상훈,장경원,조동현,유욱재,서정기,이봉수,문주현,박병기 제주대학교 방사선응용과학연구소 2008 방사선응용과학연구소논문집 Vol.22 No.-

In this study, a fiber-optic bundle sensor has been developed using water-equivalent organic scintillating fibers for photon beam measurement. Beam penumbra and percent depth doses(PDD) are measured according to the depth of the photon beam. This sensor has many advantages such as high resolution, real-time measurement and ease of calibration over conventional radiation measurement devices.

방사성 페기물 처리장의 지하수 온도 측정을 위한 광섬유 센서의 제작 및 특성 분석

서정기,유욱재,장경원,조동현,신상훈,이봉수 제주대학교 방사선응용과학연구소 2008 방사선응용과학연구소논문집 Vol.22 No.-

Fiber-optic temperature sensing technology can alternative to classical measurement techniques in nuclear environment, Its advantages allow low cost, a long distance measurement and real-time, In this study, we have measured the optical power of power meter and the output voltage of photodiode according to change temperature of water.

S-상 심실중격의 임상적 고찰

이동민,장경식,양종태,장대용,김종오,서영욱,고영엽,홍순표 조선대학교 부설 의학연구소 2002 The Medical Journal of Chosun University Vol.27 No.1

Background: The sigmoid septum described an anatomical variation in the contour of the left ventricular outlet. It is related to degenerative change with aging. We observed clinical significance of sigmoid septum in Korean. Methods: Echocardiographic examination was performed in 434 patients. Sigmoid septum is defined as discrete bulging of the proximal interventricular septum with that thickness is greater than 1.3cm or the thickness is grater 1.5 times than adjacent mid interventricular septum in apical 3 chamber view. Result: The incidence of patient with sigmoid septum(septum patient) is 24.8% (male 8.4%, female 16.3%) . The incidence increases with age and is more common in women. The patients with sigmoid septum were compared with targeted groups, there was no significant difference in blood pressure between them, but in height and weight, the former were lower. (p<001, p<03). In the patients with sigmoid septum, weight and the surface area of a body have an opposite correlation with increase of age (p<03, r=-0.34) (p<04, r=-0.31) , but no decrease of height was found according to age increase (p=0.47, r=-0.11) The main reason patients with sigmoid septum ask echocardiolography and its clinical symptoms were abnormal results of previous electrocardiography and/or usual chest pain. Compared with control group, interventricular septal thickness is larger in septum patients (p<001). The thickness of interventricular septum located in subaortic left ventricular outflow tract is 1.6±0.3cm. There is another web like structure that continued from interventricualr septum to anterior free wall of left ventricle and the width is 1.6±0.4cm. A sign of insignificant obstruction due to left ventricular outflow was observed from three sigmoid septum patients. Conculusion: Septum patient is largely found in older age group and the body weight and body surface area are lower than control group. The body weight and body surface area are opposite correlation with age. So sigmoid septum is considered as structural change by weight reduction with aging. It is assumed that septum patients are related with asymptomatic ischemia because they have more abnormal ECG finding such as T wave inversion on precordial leads or standard leads, nonspecific ST-T change, LBBB etc. Sigmoid septum is not only proximal interventricular septal bludging but also another web like structure continuing to anterior wall of left ventricle.

두개강내로 전이된 Adenoid Cystic Carcinoma 2례 : 증례보고 Report of Two Cases

송재욱,윤상민,이창훈,장지수,이승훈,조경자,강신광 대한신경외과학회 1996 Journal of Korean neurosurgical society Vol.25 No.10

The authors describe two cases of unusual intracranial metastatic adenoid cystic carcinomas. A 42-year-old woman had a right pariental epidural metastatic mass. presumed hematogenous. spread from a primary tumor in the parotid gland. In second case, a 32-year-old man had a intracranial metastatic adenoid cystic carcinoma mimicking calcified psammomatous meningioma on CT scans. We present these unusual cases with a review of relevant literature and a discussion of possible pathogenesis.

생쥐 위장관의 Interstitial cells of Cajal(ICC)에 대한 면역조직화학적 연구

김영철,차경훈,신무경,임건한,김주영,안병수,김장만,양경철,박도영,오재욱,장인엽 조선대학교 2003 The Medical Journal of Chosun University Vol.28 No.1

Background and Objectives : Interstitial cells of Cajal(ICC) are the pacemakers in gastrointestinal tract that modulates gastrointestinal motiliey and these cells also transmit neural input from enteric nerves to smooth muscles. Recent work on tissues from patients with motility disorders that suggest that loss or defect in ICC could be related to pathophysiology in human and animal models. Immunolabelling of ICC in intestinal wall is recently developed by using specific marker, anti-c-kit antibody. Immunohistochemistry was done for ICC network in attempt to provide a morphological basis for the mechanism regulating gastrointestinal motility Methods : Cryosection was done, and whole-mount preparations of mouse stomach, gastrointestinal tract were immunolabelled using the anti-c-Kit. Immunolabelled ICC networks were observed under a confocal laser scanning microscopy. Results : According to three dimensional reconstruction study, we found that the c-Kit-positive celluar networks were widely distributed in the gastrointestinal muscle (1) circular muscle layer(IC-IM), (2) myenteric plexus(IC-MY), (3) deep muscular plexus(IC-DMP) in ileum, (4) submucosal plexus(IC-SMP) and longitudinal muscle layer(IC-LM) in colon. Conclusion : The characteristic profiles of ICC celluar networks provide a morphological basis upon the mechanism regulating gastrointestinal motility. Additional studies for the enteric nerves-ICC interaction are need to evaluate the detailed roles of Icc in gastrointestinal tract.

17β-Estradiol의 심근 보호작용에 대한 연구 ; 재관류 부정맥을 유발한 동물실험

홍정석,김원,조규종,이미우,장성은,임경수 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Background: Although reperfusion certainly prevents tissue ischemia from possible cardiac death, several lines of evidence suggest that reperfusion may paradoxically aggravate the frequency of serious reperfusion-induced lethal arrhythmias. It has been reported that acute administration of estrogen at physiological concentrations reduced with myocardial ischemic injury in women with coronary heart disease. In studies with canines, acute administration by either the intra-muscular or the intra-coronary route similarly prevented ischemia and reperfusion dysrhythmias and also reduced the infarct size because the estrogen increased the distal coronary perfusion pressure, scavenged free radicals and had other effects during both ischemia and reperfusion. However, the canine heart is notoriously well collateralized. 17β-estradiol induces very little vasorelaxation in cat coronary rings, suggesting that increased ischemic myocardial blood flow dose not contribute to the protective effect. In the present study, employing a cat model of regional cardiac ischemia, we examined whether reperfusion rendered after acute administration of 17β-estradiol could lower the incidence of reperfusion-induced lethal arrhythmia and the death rate. Method: Adult mongrel male cats(n=31, 2.7∼4.5 kg) were anesthetized under positive-pressure artificial ventilation with room air. Electrocardiograms were recorded. The animals of the control group(n=15) were subjected to 20-minute left anterior descending coronary artery(LAD) occlusion followed by abrupt reperfusion. The animals in the experimental 17β-estradiol(2 or 20 ㎍/kg) group were subjected to ischemia/reperfusion insult following drug treatment: 17 β -estradiol was applied intravenously within the 60 seconds just before LAD ligation followed by abrupt reperfusion. The Fisher's exact test was used to compare the data from different animal groups(p<0.05). Results: The number of arrhythmias(ventricular premature beat, ventricular tachycardia and ventricular fibrillation) emerging during the reperfusion phase were not statistically different from that in the control group. The death rate in the 17β-estradiol 20㎍/kg group was lower from that in the control group(P value = 0.039). Conclusion: Acute administration of 17β -estradiol at a supraphysiological concentration might produce cardioprotective effects, not by modificating the coronary blood flow into the threatened myocardial region, but by other mechanisms that directly or indirectly increase the intrinsic myocardial ischemic tolerance in the cat during the reperfusion phase.