• Applied Microscopy
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• 제25권4호
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• pp.115-123
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• 1995

This study was carried out to observe the functional ultrastructures of photoreceptor cells in frog(Rana catesbeiana) retina using transmission electron microscope. The photoreceptor cells are divided into two types-rod and cone cells-consist of outer and inner segment. The long outer segment of rod cell contains dense stacks of membrane and formed vertical and horizontal folds. The outer segment of cone cell is small, and vertical and horizontal folds are not exist. The electron dense cytoplasm of rod cell contains compact mitochondria, Golgi complexes, and endoplasmic reticula. The inner segment of cone cell shows low electron density and contains a large lipid droplet in the upper part of inner segment. In addition, cone cell contains many mitochondria, Golgi complexes. rough endoplasmic reticula, ribosomes and numerous glycogen particles. It is believed that these ultrastructural characteristics are closely associated with photoreceptive function of photoreceptor cells in frog retina.

• 한국식품영양과학회지
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• 제46권9호
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• pp.1027-1034
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• 2017

본 연구에서는 잣피 20% 주정 추출물을 첨가한 식이로 하여 바이러스에 감염되어 면역력이 결핍된 마우스에서 면역조절 효과를 확인하고자 T, B 세포의 증식능, Th1 type cytokine과 Th2 type cytokine, NK cell activity, phagocytic activity를 확인하였다. 바이러스로 인하여 AIDS와 유사하게 면역 결핍된 마우스 모델에서 cytokine의 불균형과 T 세포와 B 세포의 proliferation이 균형적으로 회복됨을 확인하였고 바이러스로 인해 자연살해세포와 대식세포의 활성능이 감소하였지만 잣피 20% 주정 추출물의 공급 시 활성능 회복에 도움을 주는 것을 확인하였다. 따라서 잣피 20% 주정 추출물은 LP-BM5 virus로 유도한 면역 결핍 마우스 모델에서 면역조절작용에 효능이 있음을 확인하였다.

• 한국안광학회지
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• 제6권1호
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• pp.81-85
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• 2001

색각은 광 수용체인 3개 R. G. B cone의 파장흡수와 대립과정의 r-g, y-b 채널에 의해 이루어진다. 전기적 회로에 의한 색각 이상 mechanism은 photo cell, relay switch, transformer로 구성하였다. 추체(cone)의 R 또는 G가 결손 된 경우 y-b chromic valence 함수가 되고, 추체의 B가 결손 된 경우는 r-g chromic valence 함수가 되어 색각 이상 mechanism을 잘 적용된다.

• Applied Microscopy
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• 제47권4호
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• pp.238-241
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• 2017

A study on the visual cell and eyeball of the endemic Korean species Liobagrus mediadiposalis was investigated by light and electron microscopes. The retina of a small and 2 mm-diameter round eye was thin, $151.0{\pm}4.0{\mu}m$ and has two visual cells, a single cone and a rod cell. The single cone cells are short and thick, $18.0{\pm}0.9{\mu}m$ in length and $5.1{\pm}0.7{\mu}m$ (n=30) in diameter, while the rod cells are longer and thinner, $54.8{\pm}2.9{\mu}m$ in length and $3.3{\pm}0.6{\mu}m$ in diameter. The cone cells are seen an irregular and random mosaic pattern, and the rod cells are also randomly situated at between cone cells. As a rare phenomenon, such structure is one of characteristics reflecting the eye of a nocturnal and bottom-dwelling freshwater fish. The ultrastructure of visual cells was observed with scanning and transmission electron microscopy, both cone and rod cells are divided into an inner segment with numerous mitochondria and an outer segment with stacks of membrane discs.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1998년도 학술발표회
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• pp.35-35
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• 1998

Catfish retina contains cone- and rod-horizontal cells. Only the cone-horizontal cell (cone-HC) has an axon and axon terminal. We compared the distribution of excitatory and inhibitory receptors in axon terminals and somata to begin to learn about the distinct functions of these two structures.(omitted)

• 한국어류학회지
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• 제20권2호
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• pp.97-104
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• 2008

한국산 고유 담수 어종인 참갈겨니와 눈동자개의 안구 외부형태와 망막구조를 광학현미경과 전자현미경으로 비교 조사하였다. 참갈겨니는 안구의 크기뿐만 아니라 수평안경/체장, 수평안경/두장의 비율이 모두 눈동자개보다 크게 나타났고 다만, 수정체직경/수평안경은 눈동자개가 더 크게 나타났다. 망막의 시각세포층에서 참갈겨니는 크게 단일원뿔세포와 이중원뿔세포, 두 종류의 원뿔세포를 가지며 단일원뿔세포는 긴단일원뿔세포와 짧은단일원뿔세포로 나뉜다. 반면 눈동자개는 긴단일원뿔세포와 짧은단일원뿔세포로 구분할 수 없는 단지 단일원뿔세포로만 구성되어 있었다. 또한 원뿔세포의 배열구조에 있어서도 참갈겨니는 보다 치밀한 열구조로 배열되어 있는 반면 눈동자개는 성긴 불규칙한 구조로 배열되어 있었다. 이상과 같이 참갈겨니와 눈동자개의 안구 및 망막의 구조적 차이는 2종 간의 생태학적 특성과 밀접한 관련이 있는 것으로 생각된다.

• 한국지반신소재학회논문집
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• 제22권4호
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• pp.83-92
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• 2023

In this study, we conducted verification of key influencing factors during cone penetration testing using the developed Mini Cone Penetration Tester (Mini-CPT), and compared the experimental results with empirical formulas to validate the equipment. The Mini-CPT was designed to measure cone penetration resistance through a Strain Gauge, and the resistance values were calibrated using a Load Cell. Moreover, the influencing factors were verified using a model ground constituted in a soil box. The primary influencing factors examined were the boundary effect of the soil box, the distance between cone penetration points, and the cone penetration speed. For the verification of these factors, the experiment was conducted with the model ground having a relative density of 63.76% in the soil box. It was observed that the sidewall effect was considerably significant, and the cone penetration resistance measured at subsequent penetration points was higher due to the influence between penetration points. However, within the speed range considered, the effect of penetration speed was almost negligible. The measured cone penetration resistance was compared with predicted values obtained from literature research, and the results were found to be similar. It is anticipated that using the developed Mini-CPT for constructing model grounds in the laboratory will lead to more accurate geotechnical property data.

• Imaging Science in Dentistry
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• 제52권1호
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• pp.109-115
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• 2022

Purpose: The aim of this study was to evaluate the prevalence of clinically relevant anatomical variations of the ethmoid sinuses and their potential association with ethmoid and maxillary sinus pathologies on cone-beam computed tomography (CBCT) scans. Additionally, potential associations with different sides and demographic factors, including age and sex, were evaluated. Materials and Methods: In total, 273 CBCT scans with complete ethmoid and maxillary sinuses were analyzed to determine the prevalence of Agger nasi cell, supraorbital ethmoid cell, Haller cell, Onodi cell, and ethmomaxillary sinus. In addition, the health or pathology of the ethmoid and maxillary sinuses was also recorded to assess correlations with the aforementioned variations. Results: The prevalence of Agger nasi cell was found to be the highest (95.6%) in this study, followed by Onodi cell (60.4%), Haller cell (29.3%), and supraorbital ethmoid cell (19.4%). Ethmomaxillary sinus was the least common finding (16.5%). Males and persons above 61 years of age had a significantly higher frequency of supraorbital ethmoid cell and Onodi cell, respectively. However, no significant relationships were noted between anatomical variations of the ethmoid sinus and pathologies of the ethmoid or maxillary sinus. Conclusion: There was a high prevalence of ethmoid sinus variations in this Southern Chinese population. The prevalence of Agger nasi cell and Onodi cell was higher than that of other anatomical variations of the ethmoid sinuses. Anatomical variations of the ethmoid sinuses were not associated with ethmoid or maxillary sinus pathologies in this patient cohort.

• Imaging Science in Dentistry
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• 제49권2호
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• pp.103-113
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• 2019

Purpose: Anatomical variations of the external nasal wall are highly important, since they play a role in obstruction or drainage of the ostiomeatal complex and ventilation and can consequently elevate the risk of pathological sinus conditions. This study aimed to assess anatomical variations of the nasal cavity and ethmoidal sinuses and their correlations on cone-beam computed tomography (CBCT) scans. Materials and Methods: This cross-sectional study evaluated CBCT scans of 250 patients, including 107 males and 143 females, to determine the prevalence of anatomical variations of the nasal cavity and ethmoidal sinuses. All images were taken using a New Tom 3G scanner. Data were analyzed using the chi-square test, Kruskal-Wallis test, and the Mann-Whitney test. Results: The most common anatomical variations were found to be nasal septal deviation (90.4%), agger nasi air cell (53.6%), superior orbital cell(47.6%), pneumatized nasal septum(40%), and Onodi air cell(37.2%). Correlations were found between nasal septal deviation and the presence of a pneumatized nasal septum, nasal spur, and Haller cell. No significant associations were noted between the age or sex of patients and the presence of anatomical variations (P>0.05). Conclusion: Radiologists and surgeons must pay close attention to the anatomical variations of the sinonasal region in the preoperative assessment to prevent perioperative complications.

• 환경생물
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• 제20권4호
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• pp.386-390
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• 2002

소나무 구과의 열개현상을 비교형태학적 형질을 통해 관찰하였다. 어린 구과에서는 조직의 분화가 완전하게 일어나지 않았지만 각 기관으로 분화되는 과정임을 알 수 있었다. 성숙한 구과와 동일 크기의 녹색 구과에서 유관속다발과 보강조직의 수축률은 각각 1.0∼l.5%와 14.0∼l6.0%였다 실편의 종단부는 유조직과 보강세포로만 구성되어 있었고, 중앙부는 종단부와 기부 두께가 비슷하였다. 기부는 실편과 실편 받침이 있어 더욱 두꺼웠으며, 유관속다발보다 보강조직이 2배 이상 두껍게 나타났다. 결론적으로 구과가 완전 성숙하여 건조됨에 따라, 종단부는 보강조직으로만 구성되어있어 조직내 수축만 일어나고 중앙부는 두 조직간 두께가 비슷해 밖으로 휘지 않는다. 그러나 실편내 기부에서 배축면에 위치한 보강조직이 두껍고, 유관속다발보다 보강조직에서 수축률이 훨씬 크므로 실편의 기부가 밖으로 펴지게 되어 구과는 열개된다.