• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.539-545
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• 2021

Radiation therapy is accompanied by adverse radiation effective. In particular, it is accompanied by disorders of the vascular system. Therefore, oxygen and nutrient deficiency occurs in the regeneration area. Eventually, osteoradionecrosis is formed in this cellular environment. According to a precedent study, bone morphogenetic protein-2 is used to overcome osteoradionecrosis. The purpose of this study was to investigate the regeneration ability of osteoradionecrosis by treating bone-forming protein-2 on a fibrinogen scaffold which is a biomaterial that is frequently used for bone regeneration after irradiation of the rat head. In addition, the purpose of this study was to verify the bone regeneration effect from the eight weeks. According to the experimental results, in the calvarial defected model of the irradiated mouse, making bone-formation was obtained after 8 weeks rather than bone-formation period in the early 4 weeks. moreover, it was found that the regenerated bone formation of the fibrinogen scaffold is formed from the inside of the bone of the defect area.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.153-158
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• 1998

The internal structures of Arabidopsis thaliana infected with beet curly top virus (BCTV) were studied by light microscopy. Hyperplasia was observed in the inflorescence stems of Arabidopsis thaliana ecotype Sei-O at 2 weeks after BCTV-Logan inoculation and callus was induced on symptomatic tissues at 4 weeks after virus inoculation. The infection processes were revealed as follows: hyperplasia of phloem tissue, necrosis of hyperplastic phloems, lacuna formation of necrotic tissues, elongation and enlargement of cortex and epidermal cells surrounding the lacuna formed phloem tissues, induction of cell division in the enlarged cortex and epidermal cells, and induction of callus tissue. Callus formation on Arabidopsis was caused by the virus infection, and virus inclusion body was observed in both phloem and callus tissue by azure-A staining.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.889-894
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• 2005

This experiment was carried out to investigate the effects of simulated acid rain (SAR) in the shoot growth and internal structure of Arabidopsis thaliana. In the shoot growth, the plants treated with SAR (pH 3.0) for 15 days showed no morphological change compared to the control plants. Some change was observed in the internal structure of the stems: the epidermis and cortex tissues of the stems treated with SAR were partly damaged. The plants treated with SAR showed no noticeable difference compared to the control plants, but morphological changes were observed in the leaf. The leaves of the plants treated with SAR showed many white necrotic spots on the part of upper epidermis. A light microscopic examination of the leaves with necrotic spots showed that the upper epidermis was severely compressed with the damaged cuticle layer and the mesophyll cells were also damaged and compressed. However, noticeable structural change of vascular bundle cells was not observed.

• Journal of fish pathology
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• v.4 no.2
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• pp.79-85
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• 1991

In Feb., 1990 an epizootic disease to masu salmon fry, Oncorhynchus masou cultured at the hatchery of rainbow trout in Samchok, Kwangwon-do have broken out and induced high mortality over 70%. Externally, the diseased fish showed dark discoloration, abdominal distension with ascites, slight exophthalmus and fecal casts. Internally, the gill and the liver of diseased fish were edematous and pale, and the stomach of moribund fish contained the milkish fluid. Microscopically there was extensive necrosis of the hematopoietic tissue in kidney and spleen, and scattered necrosis of pancreas, liver and lateral muscle. Especially, the necrosis of lamina propria, muscle layer and tela submucosa in the digestive tract known as the typical signs associated with infectious hematopoietic necrosis virus was seen clearly.

• Proceedings of the Korea Contents Association Conference
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• 2011.05a
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• pp.201-202
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• 2011

본 연구에는 7.0T 동물용 자기공명영상장치를 이용하여 인간의 췌장암 세포인 CFPAC-1를 이종 이식한 쥐에서 자기공명영상을 획득하여 최적화된 검사 Protocol을 정립하며, 동물 실험에서 밝혀진 종양특성과 확산강조영상과의 비교 분석을 해보고 현성확산계수 영상이 췌장암 이종이식 모형의 종양 세포 내부 구조에 관하여 어떠한 정보를 제공 할 수 있는지 알아보고자 한다. 13마리의 쥐의 26개의 종양을 전형적으로 주입 후에 2~4주 뒤에 직경이 5~10mm가 되었을 때 imaged 하였으며, pathologic specimenm을 위해 sacrificed 하였다. isofluoran gas anesthesia를 이용하여 동물 마취 하였다. 사용된 장비로는 small-animal MR images (7.0-T)를 (Bruker BioSpin GmbH, Rheinstetten, Germany)이용하여 Fast T2-weighted 와 single-shot EPI DW image를 얻었다. 종양은 H&E 염색과 CD31와 VEGF에 대한 면역조직학 염색을 하여 종양의 cellularity와 microvessel density(MVD), 종양 내 괴사 정도를 평가하였다. CFPAC-1의 현성확산계수값은 $0.7327{\pm}0.1075{\pm}10^{-3}mm2/s$이였으며, 현성확산계수는 종양내 괴사 정도와 연관성을 보였다(R = 0.7417, p = 0.0001) 이처럼 현성확산계수는 종양 내 괴사 정도 등의 현미경적구조변화를 반영하는 대리인자로 사용될 수 있음을 확인하였다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2022.07a
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• pp.311-312
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• 2022

본 논문에서는 딥러닝 기반 욕창 감지를 위한 욕창 객체 탐지를 연구한다. 객체 탐지 딥러닝 기법으로 RCNN, Fast R-CNN, Faster R-CNN, YOLO 등 다양한 기법이 존재하며, 각 모델의 특징 또한 다르다. 욕창은 단계별로 피부, 조직에 손상의 정도가 다르다. 낮은 단계의 경우 일반적인 피부색과 유사하게 나타나며, 높은 단계의 경우 근육, 뼈, 지지 조직 등의 괴사로 인해 삼출물 또는 괴사조직이 나타난다. 논문에서는 One-Stage Detection 기법인 YOLO를 기반으로 욕창 이미지 내부에서 욕창 탐지를 진행한다. 현재 보유하고 있는 이미지 데이터 수가 많지 않아 데이터 증강기법을 통해 데이터를 증강하여 학습에 활용하였다.

• Tuberculosis and Respiratory Diseases
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• v.44 no.2
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• pp.264-279
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• 1997

Background : To analyze the morphologic characteristics of low density lymph node in etiologic differentiation of lymphadenopathy, emphasizing the different features between tuberculosis and lung cancer, on contrast enhanced CT scan. Method : A total of 64 patients who showed low density lymph nodes on chest CT scan were analyzed. Primary causes were tuberculosis (n=28), lung cancer (n=27), malignant lymphoma (n=5) and metastasis from extrathoracic malignancies (n=4). CT scan was performed with 10mm slice thickness and 7 characteristic features were evaluated : location, size, presence or absence of the nonnecrotic lymph node, calcification, perinodal fat obliteration, thickness and evenness of the enhancing rim. Results : In patients with tuberculous lymphadenopathy, lymph nodes with uneven (68.0%) and thick (62.1%) enhancing rim were more common than lung cancer (p<0.05). Low density lymph nodes with less than 1 cm in size were found only in tuberculous lymphadenopathy(n=10). In 48.2% of patients with lung cancer, more than 1 nonnecrotic enlarged lymph node were coexisted, whereas 21.4% in patients with tuberculous lymphadenopathy(p=0.06). However, the size, location and calcification were not statistically significant between tuberculous lymphadenopathy and lung cancer. Conclusion : Tuberculous lymphadenopathy is strongly suggested when enhancing rim of enlarged lymph nodes is uneven and thick, when the coexisting nonnecrotic lymph nodes are few in number and when central low density is encountered in normal sized lymph nodes.

• The Journal of the Korean bone and joint tumor society
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• v.9 no.2
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• pp.190-199
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• 2003

Purpose: The aim of this study was to find out a clinically appliable method to insert a biodegradable solid material containing holmium-166-chitosan complex into the surgical field, and to evaluate the histological changes in the normal tissues after ${\beta}$ -ray irradiation from holmium-166 according to the dose, period and type of tissues. Materials and Methods: 3.0 mCi, 50 ${\mu}l$ of the liquid state $^{166}$Ho-chitosan complex was attached to the absorbable gelatin sponge. The radiation activity measured by dose caliberator was 1.5 mCi. These $^{166}$Ho-chitosan complex containing absorbable gelatin sponges were inserted into the thigh muscles and over the femur bones of the Wistar rats. The cases were evaluated at 2 weeks after insertion, and 4, 6 weeks with respect to the histological changes of the soft tissues and bone, the depth of the tissue necrosis, and the changes of the $^{166}$Ho-chitosan complex containing absorbable gelatin sponges. Results: At 2 weeks, the muscles showed coagulation necrosis, degenerating myocytes, regenerating myocytes, intermuscular edema, and inflammatory cells. The necrosis depth was 3.3 mm. In the bones, there was no osteocyte in the lacuna of cortex (empty lacuna), marrow fibrosis, inflammation. The necrosis depth was 2.9 mm. At 4 weeks, in the muscle, calcification and increased fibrosis with necrosis depth by 3.3 mm were the additional findings. In the bone, marrow fibrosis with necrosis depth by 3.3 mm were detected. At 6 weeks, soft tissue shrinkage, increased fibrosis and granulation tissue formation, and nearly resolving inflammatory reaction were the findings. Conclusion: The local application of the $^{166}$Ho-chitosan complex attached to biodegradable gelatin material with surgery in the laboratory animals resulted in no mortality and morbidity, and satisfactory tissue necrosis. Holmium-166 can be applied to the treatment of the malignant tumor patients.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.144-151
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• 2012

Diagnosis of nutrient disorders in cultivating crops is based on the visual symptoms and results of soil and plant analysis. This study was carried out to investigate the influence of B concentrations in fertilizer solution on the growth of and nutrient uptake by domestically bred strawberries. Tissue analysis based on the dry weight were also conducted to determine the threshold levels in plants when toxicity developed in boron. The growth was seriously restricted in the three strawberry cultivars as the B concentrations in fertilizer solution were elevated. The fresh and dry weights were heavier and crown diameters were thicker in the 0.25 mM boron treatment than the other treatments tested. The toxicity symptoms of boron appeared on the older leaves of three strawberry cultivars while interveinal chlorosis symptoms appeared on the young leaves of 'Keumhyang' and 'Seolhyang' strawberries. The toxicity symptoms in lower leaves were developed when B concentrations in fertilizer solution were higher than 2 mM in 'Keumhyang' and 0.5 mM in 'Maehyang' and 'Seolhyang' strawberries. The elevated boron concentrations in fertilizer solution did not influence the tissue K, Ca, and Mg contents, but influenced the phosphorus contents with decreasing tendency. The tissue Fe and Zn contents decreased and increased, respectively, as the B concentrations in fertilizer solution were elevated. When the concentration of boron at which the growth of a plant is retarded by 10% is regarded as a upper threshold level, the boron contents based on dry weight of above ground plant tissue should be lower than 25.1, 44.2, and 62.5 $mg{\cdot}kg^{-1}$ in 'Keumhyang', 'Maehyang', and 'Seolhyang' strawberries, respectively.

• Journal of the Korean Society of Radiology
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• v.81 no.2
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• pp.423-427
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• 2020

Angiosarcoma is a malignant endothelial cell tumor of lymphatic or vascular origin and is most commonly found in the skin and soft tissue. Primary mesenteric angiosarcoma has rarely been reported. Here, we present a case of primary mesenteric angiosarcoma manifesting as a gradually enhancing mass along with necrosis and hemorrhage.