• Nuclear Engineering and Technology
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• 제25권3호
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• pp.413-423
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• 1993

본 논문에서는 경수로 노심 용융사고시 1차계통의 압력이 높은 경우에 발생하는 격납용기 직접가열 현상에 대한 실험연구를 하였다. 실험은 고리 1,2호기와 영광 3,4호기의 1/30 축소규모와 고리 1,2호기의 1/20 축소규모를 실험모형으로 하여 수행되었으며, 고리 1,2호기의 경우 축소 규모에 따른 검증도 시도하였다. 실험의 주요 변수는 초기 압력 용기의 압력, 파열면적 및 캐비티의 구조 등이다. 실험결과로부터 캐비티 외부로의 용융노심 분사비율은 높은 초기압력과 큰 파열면적을 가진 경우가 더 높으며 캐 비티의 구조가 분사비율에 큰 영향을 미침을 알 수 있었다. 본 연구의 실험결과를 이용하여 분사비율에 대한 실험관계식을 무차원 유효시간의 함수로 도출하여 제시하였으며, 이 실험관계식은 본 실험결과 뿐만 아니라 한국 과학기술원의 실험자료 및 미국 BNL 실험결과와도 잘 일치하였다.

• 대한영상의학회지
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• 제83권1호
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• pp.178-183
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• 2022

진성적혈구증가증은 드문 골수 증식성 질환이며 제어되지 않은 적혈구 생산으로 인해 절대 적혈구 질량이 증가한다. 진성적혈구증가증은 큰 혈관의 협착 또는 폐색과 함께 허혈성 뇌졸중의 위험이 높다. 진성적혈구증가증 환자에서 뇌경색에 대한 많은 증례 보고가 있다. 그러나 합병증으로 뇌졸중이 발생한 진성적혈구증가증 환자의 좁아진 혈관에서 혈관벽 자기공명영상 소견은 보고되지 않았다. 저자들은 뇌졸중으로 인해 입원한 후 PV로 진단된 30세 남성의 경동맥 VW-MRI 소견에 관해 보고하고자 하며, 이는 우리가 아는 한 영어로 된 첫 번째 보고이다.

• BMB Reports
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• 제48권5호
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• pp.271-276
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• 2015

Baicalin is a flavonoid derived from the dried root of Scutellaria baicalensis. In this study, oxygen-induced retinopathy was used to characterize the anti-angiogenic properties of baicalin in mice. Pups were exposed to a hyperbaric oxygen environment to induce retinal angiogenesis and were subjected to intraperitoneal injection of baicalin. Avascular area, neovascular tufts, and neovascular lumens were quantified from digital images. Compared to the vehicle, baicalin clearly reduced the central avascular zone and the number of neovascular tufts and lumens. High-dose baicalin (10 mg/kg) significantly reduced the expression of matrix metalloproteinase-2 (MMP-2), MMP-9, angiotensin II, and vascular endothelial growth factor (VEGF). These results show that baicalin is a powerful antiangiogenic compound that attenuates new vessel formation in the retina after systemic administration, and is a candidate substance for therapeutic inhibition of retinal angiogenesis. [BMB Reports 2015; 48(5): 271-276]

• 기계저널
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• 제18권4호
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• pp.35-40
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• 1978

여기서 상기 ASME Code에 대하여 간단히 설명하기로 한다. ASME Code 는 첫부분에서 ASME Code의 적용을 받아야 하는 압력용기를 정의하고, 압력용기의 건설에 관한 일반원칙을 설명한후 그 다음에는 세개의 Subsection으로 나뉘어져 있다. 즉 Subsection A General Requirements Subsection B Requirements Pertaining to Methods of Fabrication of Pressure Vessels Subsection C Requirements Pertaining to Classes of Material 여기서 Subsection A는 압력용기 재료나 제작방법의 상위와 관계없이 적용하여야 할 일반적인 요구사항을 규정한 것이며, Subsedction B에서는 압력용기의 제작방법을 용접,리벳팅,단조,경납 땜의 4가지로 나누어 각 제작방법에 따른 특수 요구사항을 규정하였고, 마지막으로 Subsection C 는 재료에 따른 특수 요구사항을 규정한 것이다. 이 각 Subsection은 다시 General, Materials, Design, Fabrication, Inspection and Tests, Stamping and Reports, Pressure Relief Devices로 나누어 이에 대한 각각의 요구사항들을 설명하고 있다. 그러나 이 기술기준에서는 제정방향으로, 다음의 목차에서도 알 수 있는 바와 같이 이들의 순서를 바꾸어 총칙,재료,설계,제작, 검사 및 시험, 압력릴리프장치를 배치한 후 이미 KS B 6231에 제정되어 있는 것은 그 규정을 대부분 그 대로 인용하였고, 그렇지않은 것은 우리의 실정을 참작하여 삭제, 보완, 수정하였다. 삭제한 내용 중 대표적인 것으로 공인검사관(Authorized Inspector) 및 Stamping and Reports 에는 9개의 Mandatory Appendix 와 16개의 Nonmandatory Appendix가 있는데, 이둘 중 이 기술기준에서 필요하다고 생각되는 것은 발췌 수록하였다. 단위에 대해서는 국가시책에 따라 메트릭 시스템을 사용하였고 단위의 환산에서 야기되는 소수점등의 처리는 공학적인 판단에 의거하였다.

• Journal of Korean Neurosurgical Society
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• 제45권4호
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• pp.236-239
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• 2009

Carotid occlusion is an inevitable therapeutic modality for the treatment of complex aneurysms such as giant, traumatic, and intracavernous aneurysms. Late complications of carotid occlusion include 'de novo' aneurysm formation at a distant site because of hemodynamic changes in the circle of Willis. We report a case of de novo aneurysm in a vessel that appeared to be normal on initial angiography. The patient developed an anterior communicating artery aneurysm and marked growth of a basilar bifurcation aneurysm 9 years after trapping of the left internal carotid artery for the treatment of a ruptured large saccular aneurysm involving ophthalmic and cavernous segments. We propose that patients who undergo therapeutic carotid occlusion should be periodically followed by magnetic resonance angiography or computed tomographic angiography to evaluate the possibility of de novo aneurysm formation; this advice is in line with previous reports.

• Journal of Chest Surgery
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• 제17권4호
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• pp.691-697
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• 1984

After the real birth of vascular surgery occurred with the introduction of the first practical arterial prosthesis about 50 years ago, a variety of potential vascular graft had been tested and rejected. Polytetrafluoroethylene [Teflon, PTFE] was first used as a vascular prosthesis in 1957. Thereafter this pros-thesis was first used clinically in 1972 and has subsequently been widely applied as a small and medium sized vessel replacement because it is easy to use and readily available. There are numerous reports of good results about Polytetrafluoroethylene graft. We experienced the three cases of arterial bypass graft using polytetrafluoroethylene vascular pros-thesis. First, 21 years old female patient had suffered from Takayasus disease which affected the left subclavian artery and right subclavian-left axillary extra anatomical bypass graft as done. Second, 64 years old male patient had suffered from Leriche syndrome for 12 years and the left axillofemoral and femorofemoral extra anatomical bypass graft was done. Third, 34 years old male patient had suffered from recurrent Buergers disease which affected the left popliteal artery and the isolated popliteal artery segment bypass graft was done. Relatively satisfactory result was obtained in early post-operative period in all three cases.

• Journal of Korean Neurosurgical Society
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• 제42권4호
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• pp.342-345
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• 2007

The azygos anterior cerebral artery, a rare anomaly in the circle of Willis in which only a single vessel supplies the medial aspects of both anterior cerebral hemispheres, is closely associated with saccular aneurysms. We present three cases of azygos anterior cerebral artery aneurysms among the 781 cerebral aneurysms surgically treated at our institution in an 11-year period. These three cases all involved elderly women who presented with subarachnoid hemorrhage. Conventional cerebral angiography and CT angiography revealed small saccular aneurysms at the distal ends of the azygos anterior cerebral arteries. These aneurysms were clipped successfully using a bifrontal interhemispheric approach. Hence, the pathogenesis of these particular aneurysms relating to hemodynamic change, associated anomalies, and surgical pitfalls is discussed with review of literature.

• Journal of Yeungnam Medical Science
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• 제25권2호
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• pp.175-181
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• 2008

Central venous catheterization via an internal jugular vein or subclavian vein has become a common procedure in monitoring CVP and managing severely ill patients. However, there have beennumerous reports of complications associated with central venous catheterization. These include vessel injury, pneumothorax, hemothorax, nerve injury, arrhythmias, arteriovenous thrombosis, pulmonary embolism, and infection at the insertion site. We report a case of hemothorax after subclavian vein catheterization failure, along with successful treatment.

• BMB Reports
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• 제49권5호
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• pp.255-262
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• 2016

The disease known as cerebral cavernous malformations mostly occurs in the central nervous system, and their typical histological presentations are multiple lumen formation and vascular leakage at the brain capillary level, resulting in disruption of the blood-brain barrier. These abnormalities result in severe neurological symptoms such as seizures, focal neurological deficits and hemorrhagic strokes. CCM research has identified 'loss of function' mutations of three ccm genes responsible for the disease and also complex regulation of multiple signaling pathways including the WNT/β-catenin pathway, TGF-β and Notch signaling by the ccm genes. Although CCM research is a relatively new and small scientific field, as CCM research has the potential to regulate systemic blood vessel permeability and angiogenesis including that of the blood-brain barrier, this field is growing rapidly. In this review, I will provide a brief overview of CCM pathogenesis and function of ccm genes based on recent progress in CCM research.

• Plant Biotechnology Reports
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• 제2권2호
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• pp.133-136
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• 2008

Cell cultures of Commiphora wightii (Arnott.) Bhandari were grown in shake flasks and a bioreactor and an increase in guggulsterone accumulation up to $18{\mu}g\;l^{-1}$ was recorded in cells grown in the production medium containing a combination of sucrose:glucose (4% total), precursors (phenylalanine, pyruvic acid, xylose, and sodium acetate), morphactin, and 2iP. A yield of $10g\;l^{-1}$ biomass and ${\sim}200{\mu}g\;l^{-1}$ guggulsterone was recorded in a 3-l flask and in a 2-l stirred tank bioreactor compared with 6.6 g biomass and $67{\mu}g\;l^{-1}$ guggulsterone in 250-ml flasks. Increased vessel size was correlated with increased biomass and guggulsterone accumulation. 2iP alone was not effective for biomass and guggulsterone accumulation in cell cultures of C. wightii.