• Animal cells and systems
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• 제3권4호
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• pp.407-412
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• 1999

The influence of eating habits and food type on the ultrastructural characteristics of the digestive tracts was studied under the scanning and transmission electron microscopes in two crustacean decapods (Hemigrapsus penicillatus De Haan; mud crab, Pinnotheres cyclinus Shen; symbiotic crab). The relative ratio of the length of midgut versus hindgut was 1:1 in the mud crab, but 4:1 in the symbiotic crab. Observation through the scanning electron microscope revealed that the midguts of both species have densely-arranged longitudinal mucosal folds with a smooth surface. In the hindgut of the mud crab, mucosal folds were longitudinally oriented, clusters of two to five spines were observed on the cuticular surface, and the length of the spine in the distal hindgut was longer than that in the proximal portion. In the symbiotic crab, the mucosal folds were irregulary arranged, and numerous rudimentary spinal structures were noted on the cuticular surface. Through observation of a transmission electron microscope, the epithelial cells of the midgut in both species had numerous microvilli, but the length of the microvilli was slightly longer in the mud crab than in the symbiotic crab. The central layer of the basement membrane and the muscular layer of the midgut were more developed in the mud crab than in the symbiotic crab. The thickness of the cuticular layer over the hindgut surface in the mud crab was about 4 times than that of the symbiotic crab.

• Applied Microscopy
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• 제17권1호
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• pp.29-46
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• 1987

To study hexavalent chromium effects on mitochondrial electron transport, the activities of electron transport enzymes and conformational change of mitochondria treated with $40{\mu}M$ of sodium dichromate ($Na_{2}Cr_{2}O_{7}\;2H_{2}O$) were investigated. And so were those of liver mitochondria isolated from mouse intraperitoneally injected with sodium dichromate, 40mg per kg body weight. On both treatment with chromium(VI), the activities of electron transfer enzymes (Complex I and IV) were increased to some extent and the ultrastructural transformation of mitochondria from a condensed to an orthodox conformation was inhibited under State IV respiration. These results represent' inhibitory effect of hexavalent chromium on electron transport without inhibiting electron transfer enzymes (Complex I and IV) in mitochondria. On intraperitoneal treatment with hexavalent chromium as sodium dichromate and trivalent chromium as chromic chloride, containing 37.5 mg of chromium per kg body weight, respectively, the activities of electron transfer enzymes of liver isolated from mouse with chromium(VI) was reduced, but that with chromium(III) was not affected. And with chromium(VI), all mice after 12 hours of treatment died, only after 6 hours survived. With chromium(III), however, all survived. This indicates that hexavalent chromium is more toxic than trivalent chromiumin mouse liver.

• The Journal of Korean Physical Therapy
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• 제16권2호
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• pp.63-71
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• 2004

Denervated skeletal muscle produces muscle atrophy as well as changes at the neuromuscular junction which leads to terminal axonal sprouting and an ultrastructural remodeling. NT-3 is expressed in adult muscle and motoneurons. Normally NT-3 has a potential role in regulating adult neuromuscular jungtion and recovering following muscle atrophy. Also, it could influence synaptic neurotransmission between motoneurons and skeletal muscle cells. The purpose of this study was to investigate the effect of electrical stimulation therapy(EST) on NT-3 expression in neuromuscular junction following sciatic nerve transsection in rats. After EST application during 7 days, the immunoreactivity of NT-3 was increased in neuromuscular junction

• 대한수의학회지
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• 제19권1호
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• pp.33-44
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• 1979

Herpes virus인 소의 전염성 비기관염 바이러스와 악성 카탈열 바이러스의 형태(形態)와 그 형성과정(形成過程)(형태발생(形態發生))을 조직배양(組織培養)에서 각기 시험(試驗)하였다. 이 두 종류(種類)의 바이러스는 herpes virus의 특징적(特徵的)인 구조(構造)를 가지나 그 형태발생(形態發生)이 상이(相異)함을 밝혔다. 1. 소의 전염성비기관염(傳染性鼻氣管炎) 바이러스 (IBRV/CT3) 배양에서 그 바이러스의 envelope는 세포질막(細胞質膜)으로부터 유래(由來)됨을 밝혔다. 2. IBRV/CT3 배양에서 envelope는 가진 바이러스는 세포핵내(細胞核內)에는 전혀 나타나지 않았다. 3. 소의 악성(惡性)카탈열(熱) 바이러스(MCFV/C500)의 배양에서 그 바이러스의 envelope는 세포핵막(細胞核膜)으로부터 유래(由來)됨을 밝혔다. 4. 소의 악성(惡性)카탈열(熱) 바이러스(MCFV/C500)에 감염(感染)된 토끼의 폐장(肺臟)에서 얻은 macrophage에 대해 바이러스의 소재(所在)를 추구(追究)한바, 이 바이러스는 macrophage의 세포질내(細胞質內)에만 존재(存在)함을 밝혔다. 그리고 이 바이러스는 탐식(貪食)된 바이러스임을 알았다.

• 대한한의학회지
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• 제22권4호
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• pp.79-89
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• 2001

Objectives : This study has been carried out to investigate the effects of the Saengjinyanghyutang-gamibang and Rosa rugosa extracts on pancreas of the hyperglycemia mice induced with streptozotocin. Methods : We examined immunohistochemistry for insulin and COX-2, ultrastructural changes of acini by electron microscope, and changes of the blood glucose and BUN levels. Results : The ${\beta}-cells$ on Langerhnan's islet were destructed by administration of streptozotocin, so that few insulin-positive cells were observed in the control group. However, a lot of insulin-positive cells were observed in the experimental groups. These cells had recovered from the damage. As a result of COX-2 immunostain, COX-2 expression were highest in the control group other than the Saengjinyanghyutang-gamibang and Rosa rugosa extracts administered groups. As the electron microscopical observation, the centroacinar cells and acini of pancreas were destructed or damaged by administration of streptozotocin in the control group, but these recovered !Tom the damage in the other experimental groups. The levels of serum glucose were decreased remarkably on the Rosa rugosa and Saengjinyanghyutang-gamibang extracts administered groups compared with control group. Conclusions : These results suggest that administration of the Rosa rugosa and Saengjinyanghyultang-gamibang extracts to the mice reduced the damage induced by streptozotocin.

• 대한의생명과학회지
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• 제6권2호
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• pp.109-118
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• 2000

본 연구는 전자현미경적인 방법을 이용하여 흰쥐 기관지와 폐조직에 미치는 간접흡연의 영향을 조사하였다. 실험동물은 1일 3회씩 매회 15분간, 4주 동안 비주류 담배연기를 흡입하도록 하였다. 간접흡연 그룹의 폐조직에서는 세포질내에 다수의 용해소체을 함유하고 있는 중성구, 그리고 다양한 크기의 용해소체와 잔사체를 함유하는 대식 세포가 관찰되었다. 또한 폐포격벽은 팽대되었으며 섬유화현상이 나타났다. 기관지상피는 섬모상피세포가 점차 소실되었고, 분비세포 또는 배상세포들은 그 수가 증가하였으며, 섬모가 소실되고 표면적이 확장된 배상세포도 관찰되었다. 본 연구결과 이러한 미세구조의 변화는 간접흡연에 의한 세포상해의 전형적인 결과로 파악된다.

• 한국가축번식학회지
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• 제15권3호
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• pp.207-220
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• 1991

This study was carried out to investigate the ultrastructural changes of ooplasm and follicular membrane of oocytes, obtained from 150 of 3-year-old female rainbow trout(Oncorhynchus mykiss). All data were collected from March in 1989 to February in 1990, and from August to October in 1991. The size of the nucleoli and number of the yolk granules increased as the oocyte growed. Yolk granules were deposited in the oocyte as crystalline granules. Due to the presence of large early and late maturing oocytes, their ovaires were enlarged, transparent and granular. The lattice was broken down at hydration, leaving the egg transparent. As thepercentages of fish in LPO and EMO stage increased from September to October, Mean GSI values increased. Follicle cells such as granulosa cell and thecal cell change a squamous into cuboid shape in LPO and EMO stage. Seasonal changes in the microscopic appearance of the ovaries were well correlated with those in bothgonadosomatic index and macroscopic apearance. Under the natural conditions,t he ovarian follicle influences the histological development and periodical secretion of the hormones, sufficient for a oogenesis and gonadal steroid production. The electrophoretic pattern of major band in mature stage was much thicker(70∼110k dalton) than that in previtellogenic phase.

• Applied Microscopy
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• 제27권2호
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• pp.189-196
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• 1997

The ultrastrucures of Xenopus otic vesicle from normal embryo (st. 43) and induced otic vesicle from animal cap assay with Activin A were compared. Activin A was applied to the presumptive ectoderm at various concentrations for three days at $20^{\circ}C$. The results were almost identical to the reference studies, but it was found that the otic vesicle was induced at the concentration of 10 ng/ml in to)v rate. This otic vesicle may be secondarily induced by the neural tissue showed commonly at the concentration of 10 ng/ml. Otoliths were observed as three or four-axis crystaline bodies in the lumen of otic vesicle. In electron micrograph of the normal embryo, two kinds of microvilli were observed on the apical position of hair cells. One was small and common, the other was large-sized and sparsely distributed. In both cell of otic vesicle, mitochondria, golgi apparatus and multivesicular body were rich, so, they showed a lot of similarities in ultrastructure. However, the otolith was not found and microvilli were overexpressed in the otic vesicle induced by Activin A.

• The Plant Pathology Journal
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• 제17권3호
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• pp.128-140
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• 2001

Infection of pepper leaves by Colletotrichum cocodes at the two- and eight-leaf stages caused susceptible and resistant lesions 96 h after inoculation, respectively. At the two-leaf stage, progressive symptom development occurred on the infected leaves. In contrast, localized necrotic spots were characteristic symptoms at the eight-leaf stage. Infected leaves at the two-leaf stage exhibited cell death accompanied by the accumulation of autofluorescent compounds. At the eight-leaf stage, pepper leaves infected by the anthracnose fungus displayed localized autofluorescence from the symptoms. Infection of pepper leaves by C. cocodes at the two-leaf stage resulted in its rapidand massive colonization of all the leaf tissues including the vascular tissue, together with cytoplasmic collapse, distortion of chloroplasts, and disruption of host cell walls. However, penetration of C. cocodes was very limited in the older leaf tissues of pepper plants at the eight-leaf stage. Fungal hyphae grew only in the intramural spaces of the epidermal cell walls at this stage. Occlusion of amorphous material in xylem vessels, aggregation of fibrillar material in inter-cellular spaces, and deposition of protein bodies were found as resistance responses to C. cocodes.

• Journal of Chest Surgery
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• 제21권2호
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• pp.246-253
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• 1988

An in vitro model providing with a recirculating perfusion apparatus using an isolated canine heart and its autogenous blood, which was prepared for study of myocardial protection method. This apparatus was easily used by quick connect system and maintained well heart function for about 2 hours. The Langendorff perfusion was initiated for a 10 minute period by introducing perfusate at 37` into the aorta from aortic reservoir located 100 cm above the heart. The isolated perfused working canine heart model was a left heart preparation in which oxygenated perfusion medium [at 37K] entered the cannulated left atrium at a constant flow rate [900ml/ min] under 20 mmHg overflow system and was spontaneously ejected[no electrical pacing] via an cannula against a hydrostatic pressure of 80 cm H2O. During this working period, various indices of cardiac function were measured. The cardiac functions were stable for over 2 hours with perfusion of Krebs-Henseleit solution and autologous blood[1:1] mixture in volume and maintained heart rate ]]3-122/bpm peak systolic pressure 109-113 mmHg, cardiac output 900 ml / min and left atrial mean pressure 8-9 mmHg. In this model, the efficiency of myocardia] protection could be easily measured by means of functional, enzymatic, biochemical and ultrastructural assessment. And also, we believe this model to be a useful assessment screening model of recovery state after long duration of myocardial preservation of donor heart without difficult transplantation procedures.