• Journal of Radiation Protection and Research
• /
• 제36권2호
• /
• pp.79-85
• /
• 2011

본 논고의 목적은 듀얼 에너지 시스템의 금속 인공물 감약 (MAR) 기법을 팬텀과 환자를 대상으로 적용하여보고 그 유용성에 대해서 알아보고자 한다. 사용한 장비는 GE사(社)의 750HD CT이고 AW 4.5 볼륨 share 4 워크스테이션에서 영상 분석을 하였다. 팬텀으로는 victoreen사(社)의 사람 모형 흉부팬텀을 사용하였고 사람 대상은 2010년 12월 20일부터 2011년 2월 10일까지 금속물질이 삽입된 환자 25명을 대상으로 목 부위와 복부 부위에 MAR 알고리즘을 적용하였다. 사용한 파라미터는 복부검사의 경우 GSI-4Body-Large 0.9 sec 40 mm이고 목 부위에서는 GSI-3Body-Medium 0.5 sec 40 mm를 선택하여 시행하였다. 영상시험은 국립암센터 CT영상실에서 기본적으로 시행하고 있는 프로토콜에 MAR 옵션을 적용하여 동일하게 시행하였다. 영상분석은 MAR기법을 적용한 영상과 적용하지 않은 영상에서 검은색 인공물과 줄무늬 인공물이 있는 부위에 관심부위 (ROI)를 설정한 후 hounsfield unit(HU)과 노이즈를 이용한 정량적 평가를 하였고 임상 경험이 풍부한 의사와 방사선사가 CT영상에 대한 평가를 하여 MAR 알고리즘에 대한 유용성을 비교하였다. 환자 대상 시험 결과 MAR 알고리즘을 적용함으로서 금속 인공물이 있는 부위에서의 검은색 인공물(금속이 있는 부위) 과 줄무늬 인공물이 있는 영상에서 HU의 p값이 각각 p=0.01과 p=0.04를 보였지만 금속 인공물의 영향에서 벗어난 부위에서의 노이즈는 오히려 증가하는 모습을 보였다(p=0.05). 그리고 그 외의 영상(금속이 있는 부위에서 1 cm 떨어진 단면 영상) 에서 검은색 인공물과 줄무늬 인공물 부위의 HU와 노이즈의 p값에 대해서는 통계적 유의성은 만족하지 못하였지만 대체적으로 MAR알고리즘을 적용함으로서 금속인공물 발생이 감약 되는 결과를 보였다. 결론적으로 금속 물질이 삽입된 환자의 경우에 MAR 알고리즘을 적용함으로서 조직의 선예도가 적용하지 안했을 때보다 증가하였고 검은색 인공물 발생 또한 개선되는 모습을 보였다.

• 대한의생명과학회지
• /
• 제3권2호
• /
• pp.151-160
• /
• 1997

본 연구는 카드뮴의 이용 및 환경 오염의 증가로 일어날 수 있는 카드뮴 중독에 대한 새로운 생물학적 지표로서의 요중 ascorbic acid를 평가하기 위하여 실험적으로 중독시킨 Sprague-Dawley종의 흰쥐를 이용하여 요중 ascorbic acid측정, 신장의 조직병리학적 조사 및 생화학적 간 기능 검사를 실시하였다. 측정 된 요중 ascorbic acid 농도의 전 실험기간 (50일) 평균치는 실험군I (카드뮴 100 ppm)이 214.0 mg/dl, 실험군II (카드뮴 200 ppm)가 254.3 mg/dl로 대조군 9.0 mg/dl에 비해 각각 24배 및 28배의 증가를 보였다. 조직병리학적 소견으로는 신장의 근위 세뇨관에서 단백뇨의 원인으로 추정되는 호산성 초자양 물질이 관찰되어 신장의 손상이 있었고, 생화학적 분석에서 실험군I에서 AST, ALT의 수치가 대조군의 143 mg/dl, 50 mg/dl에 비해 각각 199 mg/dl, 88 mg/dl, 실험군II가 270 mg/dl, 226 mg/dl로 나타나 간 기능의 손상이 있었음을 알 수 있었다. 이상의 결과로 실험동물이 카드뮴에 노출됨에 따라 그 아만성 독성으로서 간장 및 신장 기능의 손상이 있었고 또한 요중의 ascorbic acid가 현저하게 증가되어 요중 ascorbic acid가 실험 동물의 카드뮴 노출에 대한 noninvasive 진단 지표로서 활용될 수 있을 것으로 기대된다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권5호
• /
• pp.2717-2722
• /
• 2013

Background: The objective of this research is the computed axial tomography (CT) imaging grading of radiation induced pneumonitis (RP) and its correlation with clinical and radiotherapeutic parameters. Materials and Methods: The chest CT films of 20 patients with non-small cell lung cancer who have undergone threedimensional conformal radiation therapy were reviewed. The proposed CT grading of RP is supported on solely radiological diagnosis criteria and distinguishes five grades. The manifestation of RP was also correlated with any positive pre-existing chronic obstructive pulmonary disease (COPD) history, smoking history, the FEV1 value, and the dosimetric variable V20. Results: The CT grading of RP was as follows: 3 patients (15%) presented with ground glass opacity (grade 1), 9 patients (45%) were classified as grade 2, 7 patients (35%) presented with focal consolidation, with or without elements of fibrosis (grade 3), and only one patient (5%) presented with opacity with accompanying atelectasis and loss of pulmonary volume (grade 4). Both univariate and multivariate analysis revealed as prognostic factors for the radiological grading of RP the reduction of FEV1 and the V20 (P=0.026 and P=0.003, respectively). There was also a significant (P<0.001) correlation of radiological grading of RP with FEV1 and V20 (spearman rho 0.92 and 0.93, respectively). Conclusions: The high correlation of the proposed radiological grading with the FEV1 and the V20 is giving a satisfactory clinical validity. Although the proposed grading scale seems relevant to clinical practice, further studies are needed for the confirmation of its validity and reliability.

• 대한핵의학회지
• /
• 제24권2호
• /
• pp.222-228
• /
• 1990

The development of histomorphometric and histodynamic investigations has permitted the description of a specific and complex osteopathy in hyperthyroidism. The increased bone turnover rate in hyperthyroid patients may be accompanied by a considerable bone loss. These features are associated with both inclosed osteoclastic bone resorption and increased osteoblastric bone formation, with an accelerated calcification rate. Conventional biochemical markers of bone metabolism, i.e. serum calcium and alkaline phosphatase and urinary hydroxyproline and calcium are normal in most patients with hyperthyroidism. However, the correlation between serum BGP and serum concentration of thyroid hormon suggests that serum BGP may be a sensitive marker of increased bone formation due to the hypersecretion of thyroid hormones. Any increase in bone turnover, whether focal or diffuse, will result in an increase in $^{99m}Tc-methylenediphosphonate$ uptake (MDP). The measurement of this uptake in hyperthyroid patients by bone provides a sensitive and objective means of quantifying skeletal metabolism. Using a standard shadow-shield whole-body monitor and radioimmunoassay kit, we have measured whole-body retention of $^{99m}Tc-MDP$ up to 24hr and concentration of serum Osteocalcin in 20 patients with hyperthyroidism and in 42 normals. The results were as follows; 1) The average of serum Osteocalcin level in 42 patients with normals was $9.90{\pm}4.87(ng/ml)$ and in 20 patients with hyperthyroidism was $19.54{\pm}5.7(ng/ml)$. Both the averages of serum Osteocalcin and 24hr $^{99m}Tc-MDP$ uptakes in hyperthyroid patients were higher than those in normals. 2) $^{99m}Tc-MDP$ uptakes in skeletal system increased in proportion to normal ageing after 40 yrs old in 42 patients with normals. The average of $^{99m}Tc-MDP$ uptakes in hyperthyroid patients were higher than those in normals without related ageing. 3) A significant relationships between the $^{99m}Tc-MDP$ uptakes and serum Osteocalcin level were peformed (r=0.55, $y=17.58+6.7\times$). From the above results we concluded that the measurement of serum Osteocalcin and 24hr $^{99m}Tc-MDP$ uptakes can be used for evaluation of bone turnover as a specific marker in hyperthyroid patients.

• Journal of Korean Neurosurgical Society
• /
• 제46권3호
• /
• pp.232-238
• /
• 2009

Objective : Intracranial aneurysms are sometimes presented with visual symptoms by their rupture or direct compression of the optic nerve. It is because their prevalent sites are anatomically located close to the optic pathway. Anterior communicating artery is especially located in close proximity to optic nerve. Aneurysm arising in this area can produce visual symptoms according to their direction while the size is small. Clinical importance of visual symptoms presented by aneurysmal optic nerve compression is stressed in this study. Methods : Retrospective analysis of ruptured anterior communicating artery aneurysms compressing optic apparatus were carried out. Total 33 cases were enrolled in this study. Optic nerve compression of the aneurysms was confirmed by the surgical fields. Results : In 33 cases among 351 cases of ruptured anterior communicating artery aneurysms treated surgically, from 1991 to 2000, the dome of aneurysm was compressed in optic pathway. In some cases, aneurysm impacted into the optic nerve that deep hollowness was found when the aneurysm sac was removed during operation. Among 33 cases, 10 cases presented with preoperative visual symptoms, such as visual dimness (5), unilateral visual field defect (2) or unilateral visual loss (3), 20 cases had no visual symptoms. Visual symptoms could not be checked in 3 cases due to the poor mental state. In 6 cases among 20 cases having no visual symptoms, optic nerve was deeply compressed by the dome of aneurysm which was seen in the surgical field. Of 10 patients who had visual symptoms, 8 showed improvement in visual symptoms within 6 months after clipping of aneurysms. In 2 cases, the visual symptoms did not recover. Conclusion : Anterior communicating artery aneurysm can cause visual symptoms by compressing the optic nerve or direct rupture to the optic nerve with focal hematoma formation. We emphasize that cerebral vascular study is highly recommended to detect intracranial aneurysm before its rupture in the case of normal CT findings with visual symptoms and frequent headache.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2007년도 동계학술발표대회 논문집
• /
• pp.570-575
• /
• 2007

The thermal performance of the air receiver filled with porous material for 5kWt dish solar collector installed in Inha University, Korea, is experimentally investigated. The diameter of the parabolic dish is 3.2 m, and its focal length is 2 m. It consists of 10 small pieces of glasses which have their own curvatures, and the effective reflecting area is 5.9 m2. The reflectivity of the glass is 0.95, and the thermal capacity of the system is about 5 kW thermal. The aperture diameter of the cylindrical-shape receiver which is made of stainless steel is 100 mm, and the height is 210 mm. A quartz window is installed at the receiver aperture to minimize the convective heat loss and prevent air leakages. In order to increase the heat transfer area, porous material (nickel-alloy) is inserted into the receiver. Air flows into the upper part of the receiver, which is the opposite side of the aperture. After the air flows through the inside receiver, that goes out of the receiver through 3 exits which are located near the aperture. The volumetric flow rates of air are varied from 600 to 1200 L/min. The thermal efficiency of the receiver ranges from 82% - 92% depending upon the flow rate. The results show that the system efficiency and receiver efficiency increase as the volume flow rate increases as expected. These results from the experiment will be useful for the applications to air heating receivers and solar reactors.

• 한국환경성돌연변이발암원학회지
• /
• 제26권4호
• /
• pp.125-132
• /
• 2006

Previous studies showed that epigallocatechin gallate(EGCG) have substantial effects of suppressing the N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)-initiated cell transformation process on the bases of foci formation frequency and loss of anchorage dependency. In this study we tried to clarify the molecular mechanism of suppressing the cell transformation process. Mouse cell line balb/c 3T3 A31-1-1 was exposed 2 days to MNNG followed by 15 days 12-O-tetradecanoylphorbol-13-acetate(TPA) treatment for our transformation process. EGCG was added after the time point of 24 hours exposure to TPA and incubated for 19 days. 2029 genes were selected in our transformation process that showed fold change value of 1.5 or more in the microarray gene expression analysis covering the mouse full genome. These genes were found to be involved mainly in the cell cycle pathway, focal adhesion, adherens junction, TGE-$\beta$ signaling, apoptosis, lysine degradation, insulin signaling, ECM-receptor interaction. Among the genes, we focused on the 631 genes(FC>0.5) reciprocally affected by EGCG treatment. Our study suggest that EGCG down-regulate the gene expressions of up stream signaling factors such as nemo like kinase with MAPK activity and PI3-Kinase, Ras GTPase and down stream factors such as cyclin D1, D2, H, T2, cdk6.

• 한국산학기술학회논문지
• /
• 제18권4호
• /
• pp.469-486
• /
• 2017

말레이시아에서는 전면개발방식의 도시 재개발이 주로 이루어지고 있다. 그 결과 젠트리피케이션, 역사성과 정체성의 상실, 불평등 등과 같은 사회적 문제를 야기했다. 따라서 앞으로의 말레이시아 정부는 도시 재개발에만 의존하는 것 에서 벗어나 또 다른 대안을 모색하는 것이 매우 중요하다. 지역 기반 주거재생은 낙후 지역을 총체적인 방법으로 개선하기 위하여 재개발, 회복, 재활성화 및 보전 등을 통합하는 전력이다. 본 연구 목적은 선진국 주거재생 사례를 비교 검토 하고 말레이시아에 적용 가능한 요소들을 도출하는 것이다. 이를 위해 본 연구는 문헌 검토를 통한 비교 분석을 수행하였다. 그 결과 사람중심 장소중심 체계중심의 정책을 통합하는 주거지 재생을 통해, 적절한 자원활용을 목적으로 하는 다양성의 중요성, 주민참여, 그리고 공평하고 공정하며 체계적으로 자원을 제공할 수 있도록 하는 도시 협치 등이 가능하다는 것을 발견했다. 결론적으로 말레이시아의 주거지재생은 진정한 지역 주민의 참여와 지속 가능한 재원조달 시스템을 기반으로 지역주민으로부터 시작되어야 할 것이다. 정부와 지자체는 실행자 역할을 하기 보다는 지원자 역할을 하여야 할 것이다.

• 한국건축시공학회지
• /
• 제21권5호
• /
• pp.483-493
• /
• 2021

도시 인구의 과밀화로 고층 건물에 대한 폭발적인 수요와 공급이 발생하였다. 고층 빌딩은 각 도시의 구심점으로 도시 이미지를 제고하는데 기여하고 있으나 연돌효과로 인해 승강기 문의 오작동, 외벽의 문과 창문 개폐의 어려움, 상층부로 확산하는 연기와 악취, 소음, 에너지 손실, 화재 및 오염물질의 급속한 확산 등 예기치 못한 다양한 문제를 야기하고 있다. 본 연구에서는 초고층 건축물을 수직조닝별로 구분하여 연돌효과의 원인과 해결방안을 분석하고 설계와 시공 방안으로 도출하였다. 외기를 차단하는 초기 계획과 정밀한 시공을 통한 기밀성 확보를 통해 저층부에서 유입되는 기류를 능동적으로 차단하여 건물의 내·외부 기밀성을 확보하는 방안을 모색하였다. 설비적 해결대책은 연돌효과로 인한 특정 현상을 줄이기 위한 대책이 될 수 있으나 이에 따른 2차 피해의 가능성이 높기 때문에 최소한으로 적용해야 한다. 따라서 본 연구는 연돌효과의 원인과 대책방안을 수직 조닝별로 설계적, 시공적 대책을 제시함으로써 체계적인 연돌효과 관리의 필요성을 역설하였다. 또한 본 연구가 설계 및 시공뿐만 아니라 건물 유지관리에도 도움이 되기를 기대한다.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제24권1호
• /
• pp.7-18
• /
• 2021

Purpose: The long-term efficacy and safety of infliximab (IFX) in children with ulcerative colitis (UC) have not been well-evaluated. Here, we reviewed the long-term durability and safety of IFX in our single center pediatric cohort with UC. Methods: This retrospective study included 20 children with UC who were administered IFX. Results: For induction, 5 mg/kg IFX was administered at weeks 0, 2, and 6, followed by every 8 weeks for maintenance. The dose and interval of IFX were adjusted depending on clinical decisions. Corticosteroid (CS)-free remission without dose escalation (DE) occurred in 30% and 25% of patients at weeks 30 and 54, respectively. Patients who achieved CS-free remission without DE at week 30 sustained long-term IFX treatment without colectomy. However, one-third of the patients discontinued IFX treatment because of a primary nonresponse, and one-third experienced secondary loss of response (sLOR). IFX durability was higher in patients administered IFX plus azathioprine for >6 months. Four of five patients with very early onset UC had a primary nonresponse. Infusion reactions (IRs) occurred in 10 patients, resulting in discontinuation of IFX in four of these patients. No severe opportunistic infections occurred, except in one patient who developed acute focal bacterial nephritis. Three patients developed psoriasis-like lesions. Conclusion: IFX is relatively safe and effective for children with UC. Clinical remission at week 30 was associated with long-term durability of colectomy-free IFX treatment. However, approximately two-thirds of the patients were unable to continue IFX therapy because of primary nonresponse, sLOR, IRs, and other side effects.