• Proceedings of the Membrane Society of Korea Conference
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• 1998.10a
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• pp.96-98
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• 1998

1. 서론 : 팔라듐이나 이의 합금막들은 높은 선택적 투과특성으로 인해 수소 정제나 분리막 반응기와 같은 산업응용 분야에서 매우 높은 관심을 갖고 있다. 상업적으로 이용되고 있는 이러한 막들은 통상적인 metallugical process에 의해 제조괸 self-supported type으로 수소 투과 속도가 낮을 뿐만 아니라 팔라듐 등은 고가의 귀금속이므로 비경제적이다. 따라서 현재 대부분의 연구자들은 기계적 강도를 유지하기 의한 다공성 지지체 위에 얇은 금속 박막을 코팅함으로서 투과성을 높이는 동시에 경제적인 복합막 형태의 막을 만드는데 연구의 촛점을 맞추고 있다. 이러한 형태의 막을 제조하기 위한 금속 박막 제조법은 무전해 도금법(electroless deposition), 화학증착법(CVD), 스퍼터링(sputtering), 전해도금법(electrodeposition) 등이 시도되었다. 그러나 수소에 대한 우수한 선택적 투과 특성을 갖기 의해서는 대부분 5$\mu$m 이상의 두꺼운 막을 제조하였으며 이보다 얇은 막의 제조에 한계가 있기 때문에 이들 막에 대한 기체 투과 특성에 대한 연구결과는 많지 않다. 본 연구에서는 기존의 전기도금법을 응용한 소위 'vacuum electrodeposition' 이란 새로운 기술을 도입함으로써 우수한 선택적 투과성을 갖는 2$\mu$m 이하의 팔라듐 합금 박막 제조를 가능하게 하였다. 지지체 표면의 거칠음 정도, 평균 기공 크기 등의 지지체 성질의 조절에 의한 금속 박막의 핀홀을 최소화함으로써 질소와 같은 inert gas의 투과도는 거의 없게 유지하는 동시에 금속 박막 두께, 결정 구조(e.g. grain size), 합금 조성 등을 조절함으로써 수소의 투과도를 높이고자 하였다. 있다. 후자의 경우, 미량의 과산화수소수 (1~10,000 ppm)를 이용해 처리 해주는 방법의 경우 경제적으로 큰 장점이 있고, 처리가 단순하다는 장점이 있으나 과산화수소수 자체에 포함하고 있는 높은 impurit level, 그리고 처리후 장시간의 flushing time을 가져야 한다는 단점등이 존재 하고 있다.요구된다. 몰입이 가능하여 임계치가 저하된 것으로 여겨진다. 또한 광학적 이득의 존재는 이 구조에 의한 극단파장 반도체 레이저다이오드의 실현 가능성을 나타내는 것이다.548 mL에 비해 통계학적으로 의의 있게 적었다(p<0.05). 결론: 관상동맥우회로 조성수술에서 전방온혈심정지액을 사용할 때 희석되지 많은 고농도 포타슘은 fliud overload와 수혈을 피하고 delivery kit를 사용하지 않음으로써 효과적이고 만족할 만한 심근보호 효과를 보였다.를 보였다.4주까지에서는 비교적 폐포는 정상적 구조를 유지하면서 부분적으로 소폐동맥 중막의 비후와 간질에 호산구 침윤의 소견이 특징적으로 관찰되었다. 결론: 분리 폐 관류는 정맥주입 방법에 비해 고농도의 cisplatin 투여로 인한 다른 장기에서의 농도 증가 없이 폐 조직에 약 50배 정도의 고농도 cisplatin을 투여할 수 있었으며, 또한 분리 폐 관류 시 cisplatin에 의한 직접적 폐 독성은 발견되지 않았다이 낮았으나 통계학적 의의는 없었다[10.0%(4/40) : 8.2%(20/244), p>0.05]. 결론: 비디오흉강경술에서 재발을 낮추기 위해 수술시 폐야 전체를 관찰하여 존재하는 폐기포를 놓치지 않는 것이 중요하며, 폐기포를 확인하지 못한 경우와 이차성 자연기흉에 대해서는 흉막유착술에 더 세심한 주의가 필요하다는 것을 확인하였다. 비디오흉강경수술

• Journal of fish pathology
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• v.26 no.3
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• pp.303-310
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• 2013

Since March in 2013, Inland Aquaculture Research Center, NFRDI has cultivated 1,000 wild swamp eel(Monopterus albus) for species conservation research. While cultivating, 100 fishes showed clinical sign that darkness color, mucus hypersecretion and anus rubor. Even some of them were died. Result of anatomical test, all 100 fishes were infected with intestinal parasite, acanthocephalan. So we were going to determine the case of acanthocephalans infection in swamp eel(Monopterus albus) as histopathologically. Acanthocephalan was founded in alimentary canal only. Parasite were confirmed 19 unit in individual fish, averagely. Heavy infected fishes were confirmed enterocleisis by acanthocephalans. Worms were attachment in submucosa layer of alimentary canal by invading proboscis. Characteristic symptoms were observed in stomach and intestine, including hyperemia in mucous epithelium, infiltration of eosinophills in submucosa layer, inflammation, parasitic granuloma. Some fishes showed vacuolization of gastricgland epithelium, necrosis of intestinal mucosa. Other organs, excluding alimentary canal, were not found lesion. The results of this study, the effect of the acanthocephalan infection on swamp eel(Monopterus albus) could find and it seems to be a big help in the future swamp eel(Monopterus albus) cultivation.

• Journal of the Korean Society of Radiology
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• v.84 no.3
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• pp.676-685
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• 2023

Purpose To investigate the incidence, outcomes, and imaging characteristics of clustered microcysts detected on breast US in asymptomatic women, and suggest appropriate management guidelines. Materials and Methods We identified and reviewed the lesions recorded as "clustered microcysts" on breast US performed in asymptomatic women between August 2014 and December 2019. The final diagnosis was based on pathology and imaging follow-up results for at least 12 months. Results The incidence was 1.5% and 100 patients with 117 lesions were included. Among 117 lesions, 3 (2.6%), 2 (1.7%), and 112 (95.7%) were malignant, high-risk benign, and benign lesions, respectively. The malignant lesions included two cases of ductal carcinoma in situ and one invasive ductal carcinoma. Two of them were assessed as category 4, showing mammographic suspicious microcalcifications and internal vascularity on Doppler US. The remainder was a false negative case and showed echo pattern change on the 12-month follow-up US. Conclusion The incidence of clustered microcysts on breast US in asymptomatic women was 1.5% and malignancy rate was 2.6% (3 of 117). Knowledge of outcomes and imaging features of benign and malignant clustered microcysts may be helpful for radiologists, thereby aiding categorization and management recommendations.

• The Korean Journal of Nuclear Medicine
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• v.35 no.5
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• pp.301-312
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• 2001

Purpose: Stomach cancer is one of the most common malignancies in Korea, but there is no report on FDG PET in patients with stomach cancer. We observed findings of FDG PET in patients with stomach cancer. Materials and Methods: In 13 patients with pre-operative stomach cancer, PET and CT were performed. Primary lesion and regional lymph nodes detection were aualyzed. Correlation between FDG uptake ratio and each prognostic factor of primary lesion was analyzed. In 19 patients diagnosed as recurrence or displaying suspicious symptoms, conventional work up including tumor marker and PET were performed. Recurrence detection of anastomotic site, distant metastasis, and tumor marker elevation were analyzed. Results: Sensitivity for primary lesion detection was 83.3% (CT 71.4%) and two submucosal lesions were undetected. FDG uptake ratio was variable and had no correlation with invasion-depth, size, Borrmann type, staging and differentiation. Sensitivity for regional lymph node detection was 58.3% (CT 58.3%) and the lesions less than 1cm were undetected. Sensitivity for recurrence detection was 100% but there were three false positives. Sensitivity for distant metastasis detection was 64.3% and significantly higher than that of conventional work-up (21.4%). Average of tumor marker level in patients who were confirmed as recurrence was higher than false positive. Conclusion: PET is more useful than conventional work up in distant metastasis detection when recurrence is suspected. In pre-operative stomach cancer, PET is comparable to CT for detection of primary lesion and regional lymph node metastasis and detection of distant metastasis requires further study.

• The Korean Journal of Nuclear Medicine
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• v.39 no.4
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• pp.239-245
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• 2005

Purpose: Hypereosinophilic syndrome (HES) is an infiltrative disease of eosinophils affecting multiple organs including the iung. F-18 2-fluoro-2-deoxyglucose (F-18 FDG) may accumulate at sites of inflammation or injection, making interpretation of whole body PET scan difficult in patients with cancer. This study was to evaluate the PET findings of HES with lung involvement and to find out differential PET features between lung malignancy and HES with lung involvement. Material and Methods: F-18 FDG PET and low dose chest CT scan was performed for screening of lung cancer. light patients who showed ground-glass attenuation (GGA) and consolidation on chest CT scan with peripheral blood eosinophilia werr included in this study. The patients with history of parasite infection, allergy and collagen vascular disease were excluded. CT features and FDG PET findings were meticulously evaluated for the distribution of GGA and consolidation and nodules on CT scan and mean and maximal SUV of abnormalities depicted on F-18 FDG PET scan. In eight patients, follow-up chest CT scan and FDG PET scan were done one or two weeks after initial study. Results: F-18 FDG PET scan identified metabolically active lesions in seven out of eight patients. Maximal SUV was ranged from 2.8 to 10.6 and mean SUV was ranged from 2.2 to 7.2. Remaining one patient had maximal SUV of 1.3. On follow-up FDG PET scan taken on from one to four weeks later showed decreased degree of initially noted FDG uptakes or migration of previously noted abnormal FDG uptakes. Conclusions: Lung involvement in the HES might be identified as abnormal uptake foci on FDG PET scan mimicking lung cancer. Follow-up FDG PET and CT scan for the identification of migration or resolution of abnormalities and decrement of SUV would be of help for the differentiation between lung cancer and HES with lung involvement.

• Parasites, Hosts and Diseases
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• v.28 no.1
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• pp.45-52
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• 1990

Intestinal histopathological changes due to infection with Echinostcma hortense (Trematoda) were studied in rats after experimental infection with the metacercariae. The metacercariae were obtained from the tadpoles of Rana nigrcmaculata, a second intermediate host infected in the laboratory. Total 18 albino rats(Sprague-Dawley) were given 200 matacercariae each and sacrificed on the day 1, 3, 7, 11, 22 or 44 post-infection(PI) Segments of- the small intestine at 1, 3, 5, 8 and 30 cm posterior to the pylorus(PTP) were rejected and studied histopathologically. 1. The flukes were seen to have intruded into the intervillous space in the upper small intestine at early stages(1∼3 days PI), however, they were located mainly in the intestinal lumen at later stages(7∼44 days PI) . The flukes were sucking and destroying the epithelial layers of villi with their oral and ventral suckers. 2. Histopathological changes of the intestine were recognizable in as early as 1∼3 days after infection, and the changes became severer as the infection progressed. 3. The intestinal mucosa was histopathologically characterized by villous atrophy and crypt hyperplasia throughout the infection period. Major villous changes were blunting, fusion, severe destruction and loss of epithelial layers of villi. Villous/crypt(V/C) height ratio was remarkably reduced from 3 : 1 in controls to 1 : 1 in severely infected animals. In the stroma of villi, inaamma- tory cell infiltrations, vascular congestion, edema, and/or fibrosis were recognized. The goblet cells were increased in number after 11 days PI. It was revealed in the present study that the pathological changes in the intestine of rats infected with E. hortense were chieay confined to the mucosal layer of the upper small intestine, however, the changes were very severe accompanying remarkable destruction of villi and loss of mucosal integrity, and persistent until 44 days PI.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.54-61
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• 2000

Amalgam, though a widely used dental material, does not bond to the tooth substrate Therefore, retentive preparation of the cavity is necessary. Such amalgam restorations, until corrosion products form and plug the margin, will show significant marginal leakage. Unless this is prevented early on, saliva and bacteria may enter the cavity causing postoperative hypersensitivity, dissolution and collapse of the restoration, discoloration of the margin and secondary caries, leading to shortened life-span of the restoration and pulpal pathosis. Recently, a method of restoration has been introduced whereby tooth material can be preserved, cavity margin can be sealed and preventive treatment of pit and fissure can be administered while retaining all the advantages of conventional amalgam restorations. Such sealed amalgams involve removing the carious lesion without extending the cavity for prevention and using pit and fissure sealants to seal cavity margins and pit and fissures to reduce microleakage. In this study, finishing of the amalgam and sealant application were performed after different intervals following of amalgam restoration to compare the microleakage of sealed and conventional amalgam restorations. Thirty bicuspids were prepared with Class V cavity preparations on the buccal and lingual surfaces. After amalgam placement, they were divided into the following groups and treated accordingly. Group 1 : Polishing after 24 hours Group 2 : Immediate sealant application without polishing Group 3 : No polishing, but sealant applied after thermocycling 500 times After treatment, the samples were thermocycled 500 times between $5^{\circ}C$ and $55^{\circ}C$ with a dwell time of 30 seconds. After thermocycling, the samples were dipped into 1% methylene blue kept in a $37^{\circ}C$ incubator at 100% humidity for 24 hours. The teeth were then embedded in resin and cut bucco-lingually along the tooth axis and observed with a stereomicroscope to determine the degree of microleakage, The following results were obtained : 1. Group 2 showed the least microleakeage, while group 1 showed the greatest. 2. Group 1 showed significantly greater microleakage compared to group 2 (p<0.05). However, no significant differences were found between group 1 and 3(p>0.05). No significant differences in microleakage were also found between cup 2 and 3(p<0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.3
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• pp.527-533
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• 2004

One clinical technique recommended for improving marginal integrity is "rebonding" or application of unfilled resins to the surface of composite restoration. But continuously the restorations are affected with occlusal load. There is room for doubt that the rebonding agent has the positive effect on microleakage in spite of the stress generated by the occlusal load. This study determined the effect of rebonding on microleakage of Class V resin composite restorations under load cycling. Class V cavities were prepared on the buccal surface of 40 sound extracted premolars and restored with a hybrid light-cured resin composite according to manufacturers' directions. They were randomly divided into two groups consisting of 20 samples: a control(group I), without surface sealing, and the other group(group II) in which margins were etched and rebonded. After thermocycling, each of groups was divided into subgroups(group A, B), and load cycling(total 100,000 cycles with 4-100N load at a rate of 1 Hz) were applied on the group B. Assessment of microleakage utilized methylene blue dye penetration. The following results were obtained: 1. In the occlusal region, no significant difference was noted in the scores regardless of whether or not the rebonding agent was used(group TA-IIA, IB-IIB)(p>0.05). 2. In the cervical region, the control group with rebonding(group IIA) showed the better result than the group without rebonding(group IA)(p<0.05). 3. In the cervical region, the rebonded group with load cycling(group IIB) showed similar results to the group without rebonding(group IB) and no significant difference was noted(p>0.05).

• Journal of Gastric Cancer
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• v.6 no.2
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• pp.76-83
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• 2006

Purpose: Endoscopic incision and submucosal dissection (EISD) is a technique that is being implemented for the resection of gastric adenomas and early gastric cancer (EGC). Since EISD requires a high degree of skill and experience, and due to its association with a moderate risk of gastrointestinal bleeding, its use has been limited. The objective of this study is to investigate the clinical benefits of EISD based upon clinical data on the EISD procedure. Materials and Methods: This study was conducted at Soonchunhyang University Hospital and it included 179 gastric adenoma and early gastric carcinoma lesions from 164 patients who had undergone an EISD from February 2003 to May 2005. Results: Among the total of 179 lesions, the distributions of EGC and adenomas were 70.3% (126/179) and 23.4% (42/179) respectively. The sizes of lesions were divided into 10 mm or less, $11{\sim}20\;mm,\;21{\sim}30\;mm$ and greater than 31 mm and each rates are 10.0% (18/179), 46.3% (83/179), 30% (50/179) and 15.0% (28/179). Among 120 cases which could be measured depth of lesion in according to pathologic findings, m1 (0.8%, 1/120), m2 (38.3%, 46/120), m3 (25%, 57/120), sm1 (11.7%, 14/120), sm2 (1.6%, 2/120) were diagnosed as early stages of gastric cancer. The complete resection rate was 85.2% (150/176) and en-bloc resection rate was 96.0% (169/176). Complications as such as perforation and bleeding developed in 4.4%(8/179) and 21.2% (38/179), respectively. Conclusion: EISD is an effective in the endoscopic treatment for gastric adenoma and early gastric cancers. However, further evaluation of this method and long-term follow-up will be necessary for an evaluation of the recurrence rate after resection of a tumor.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.16.2-16
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• 1982

The palatine tonsils which are located in entrance of digestive and upper respiratory tracts are the most important organ in anatomical and functional structures of the pharyngeal lymphatic tissues. As for function of the tonsil, there have been many suspected theories that were included hematopoietic, hormonal, digestive function and production of vitamin, entry of bacteria with other antigenous materials and defence mechanism of which has taken charge by Virchow in 1860 in past. But among these theories, in recently, defence mechanism of the tonsil was strongly accepted immunologically. For the purpose of elucidating immune response of the tonsil, the author observed serum immunoglobulin levels, peripheral total lymphocyte counts and populations of T, B and Null lymphocytes before and after tonsillectomy in 30 cases of patients with chronic tonsillitis and 29 cases of healthy controls. The results obtained were as follows; 1) Serum Ig M level was significantly higher in patient group than in control group but was not significantly different preoperative from postoperative patient group. 2) Population of T-lymphocyte more significantly decreased in patient group than in control group but it was not significantly different preoperative from postoperative patient group. 3) Population of B-lymphocyte more significiantly increased in patient group than in control group but it was not significantly different preoperative from postoperative patient group. On the basis of these results, it may be suggested that tonsil play partially a role in the immune response of human.