• Korean Journal of Ichthyology
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• v.19 no.1
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• pp.16-23
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• 2007

Oocyte surface in two Korean minnows, Rhynchocypris oxycephalus and R. kumgangensis was examined by light and electron microscope. In two species, the development of the oocyte was similar, but the follicular layer surrounding full-grown oocyte showed an evident difference. In R. oxycephalus, the follicular layer at the yolk vesicle stage became bilaminar with the retention of its outer squamous cell layer and the acquisition of an inner cuboidal or round cell layer just over the zona radiata. As the oocyte grows, the cuboidal cells of the inner follicular layer began to be replaced by columnar cells. At the yolk granule stage, the columnar cells secreted mucin to their cytoplasm (adhesive materials) and then surround the entire oocyte, as bundles of fence-shaped structures. Whereas, although the follicular layer of R. kumgangensis had an outer squamous layer and an inner cuboidal or round cell layer at the yolk vesicles as in R. oxycephalus, no inner cells were more changed with the retention of its cuboidal or round cells. Finally, in R. kumgangensis, the adhesive materials did not occur. In Korean two minnows, the structural difference in the oocyte surface seems to be related to their habitats and spawning characteristics as well as taxonomic characters.

• Korean Journal of Poultry Science
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• v.46 no.3
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• pp.173-183
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• 2019

Based on their virulence, the avian influenza viruses (AIVs) are classified into two pathotypes: low pathogenic avian influenza (LPAI) virus and highly pathogenic avian influenza (HPAI) virus. Among the 16 HA subtypes of AIV, only the H5 and H7 subtypes are classified as HPAI. Some AIVs, including H5 and H7 viruses, can infect humans directly. Six H7 subtype isolates from wild birds of the H7N7 (n=4) and H7N1 (n=2) subtypes were characterized in this study. Phylogenetic analysis showed that eight viral genes (HA, NA, PB2, PB1, PA, NP, M, and NS) of the H7 isolates clustered in the Eurasian lineage, the genetic diversity of which is indicated by its division into several sublineages. The Korean H7 isolates had two motifs, PEIPKGR and PELPKGR, at the HA cleavage site, which have been associated with LPAI viruses. Six H7 isolates encoded glutamine (Q) and glycine (G) at positions 226 (H3 numbering) and 228 of HA, suggesting avian-type receptor-binding specificity. None of the Korean H7 isolates had the amino acid substitutions E627K in PB2 and I368V in PB1, which are critical for efficient replication in human cells. The Korean H7 isolates showed no deletions in the NA stalk region and in NS. These results suggest that the Korean H7 isolates from wild birds are different from the H7N9 influenza viruses isolated in China in 2013, which are capable of infecting humans.

• Journal of Embryo Transfer
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• v.7 no.2
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• pp.97-110
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• 1992

돼지난포란의 안정된 체외배양 체계를 위하여 도살장에서 재취된 난소로부터 난포 및 난자난구세포체의 혀태적인 선정기준을 설정하고 이의 이론적 배경을 확립하였다. 난소를 난포상태 및 분포나 황체 존재 여부에 따라 A,B 및 C 의 세 가지 형태로 분류하고 각 type의 난소에서 직경 3-5mm인 난포로부터 난포란을 회수하였다. 회수된 난포란을 난구세포 부착상태에 따라 Good, Fair 및 Poor 의 세 가지 형태로 분류하여 각각을 호르몬이 첨가된 M16+FCS 배양액으로 35시간 동안 체외배양하여 성숙율을 비교 검토 하였다. 난소의 형태에 따라 회수된 난포란 중 Good 또는 Fair 형태는 Type A 및 C 난소에서 85%를 차지한 반면, Type B 난소에서는 53%에 불과하였다. 또한 이들 난포란을 체외배양한 결과 Type A 및 C 에서 회수된 난포란은 90 및 85%의 높은 성숙율을 보인 반면, Type C 의 난포란은 33%의 저조한 성숙을 나타냈다. 한편 핵형 분석 및 조직학적 분석에서도 Type C 난소의 경우 난포란의 핵형이 대부분 GVBD 및 퇴화 형태를 보였으며, 폐쇄포난포의 비율도 Type A 난소의 53%에 비해 월등히 높은 85%를 나타내어 성숙율 비교실험의 결과와 일치되는 경향을 나타내었다. 따라서 본 실험의 선별기준에 의한 돼지 난소 및 난포란의 형태적 분류 작업에 의해 난포란의 체외배양 성적 향상 및 안정된 배양체계의 확립이 가능하였다.

• Korean Journal of Plant Taxonomy
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• v.40 no.4
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• pp.251-254
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• 2010

We describe a new taxon of Goodyera (Orchidaceae), G. ${\times}$ tamnaensis N.S. Lee, K.S. Lee, S.H. Yeau & C.S. Lee, sp. nov., from Jeju Island. This taxon is presumed to be a hybrid between G. schlechtendaliana and G. velutina based on several morphological characteristics, i.e., leaf venation, a patterned leaf surface and raised leaf epidermal cells, the color of the flower and the bract, the lateral sepal shape, and the hair length. The morphological characteristics and illustrations of the species based on the holotype are provided together with photographs of the habitat.

• Korean Journal of Plant Taxonomy
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• v.39 no.3
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• pp.199-215
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• 2009

Phytoliths formed on the leaf-blades of the seventeen Oryza species were examined using back-scattered electron imaging. The resulting descriptions of the phytoliths became the basis for a new key to the species of the genus. This key includes features useful for specific identification related to the silica bodies originating from epidermal cells upon both the mid-vein and bulliform cell, as well as of phytoliths originating from papillae, prickle hairs, large and small trichomes, and stomatal apparatus. These detailed phytolith descriptions, back-scattered electron images, and keys to both adaxial and abaxial sides of leaves, can now be used in identifying phytoliths from archaeological samples as well as extant species of Oryza.

• Korean Journal of Plant Taxonomy
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• v.47 no.3
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• pp.222-235
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• 2017

A comparative study of the leaf epidermal micromorphology in the tribe Neillieae (Neillia: 4 species, 4 varieties; Physocarpus: 5 species; Stephanandra: 2 species) was carried out using scanning electron microscopy in order to evaluate the taxonomic and systematic implications of these characteristics. The leaves of the genera Neillia and Stephanandra were hypostomatic, whereas those of P. monogynus, P. opulifolius were amphistomatic. The range of the size of the stomata is $12.02-34.39{\times}10.76-27.13{\mu}m$; the smallest was found in N. thyrsiflora (average $13.98{\times}12.43{\mu}m$; $L{\times}W$), while the largest was measured in N. gracilis (average $26.82{\times}20.67{\mu}m$; $L{\times}W$). Paracytic stomata complexes are only found in N. affinis, and the anomocytic type was most commonly found. The papillate epidermal cell type was only observed on the abaxial surfaces of P. insularis. Platelet epicuticular waxes were found on the adaxial surfaces of N. affinis and S. tanakae. Four types (unicellular non-glandular, two- to five-armed, stellate, and glandular) of trichomes were found on the leaves. Stellates were observed in all species of Physocarpus except for P. insularis. Consequently, leaf epidermal micromorphological characteristics (e.g., the presence of papillate epidermal cells and stellate, and stomata complexes) may have high taxonomic and systematic value in Neillieae. Our results strongly support previous molecular phylogenetic and palynological hypotheses that Stephanandra and Neillia are a single genus and that Physocarpus insularis should be considered as a member of Spiraea.

• Korean Journal of Ichthyology
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• v.30 no.3
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• pp.161-166
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• 2018

The olfactory organ of Korean endemic fish Microphysogobio yaluensis are described anatomically and histologically, focused on relationship to its habitat and ecology. The paired olfactory organs are located at the dorsal snout, and externally consist of two semicircular nostrils and single nasal flap. They internally have rosette structure with 22 to 24 units of lamellae and the raphe inside the olfactory chamber. The lamella is made up of the sensory and the non-sensory epitheliums. The sensory epithelium has olfactory receptor neurons, supporting cells and basal cells whereas the nonsensory epithelium has stratified epithelial cells, ciliated non-sensory cells and mucous cells with acidic and neutral mucins. These structures might be considered that M. yaluensis has the olfactory organ which corresponds to the high sensitivity for its habitat and ecology, and is usable as a taxonomic key.

• The Korean Journal of Zoology
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• v.33 no.1
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• pp.22-27
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• 1990

The gastro-endocrine cells were examined in the fundic region of stomach of the frog, Rana rugosa, by transmission electron microscope. In the present paper, at least three kinds of cell type distributed in this region were idendfted according to their morphological charactedstics based on the size, shape and electron density of the secretory granules. Type I cells were characterized by the presence of round or oval granules (300-5OOnm in diameter) with high electron density. The granules showed a wide lucent between the contents and the limiting membrane. This cell was reminiscent of the ECL cell in the human alimentary mucosa. Type II cells were characterized by the presence of spherical or oval granules (11O-230nm in diameter) with low or high electron density. The granules showed a clear halo between the homogenous contents and the limiting membrane. This cell was reminiscent of the G cell in the human alimentary mucosa. Type Ill cells were characterized by the presence of elongated oval or pheomorphic granules (50-2OOnm in diameter) with low or moderate electron density and abundant microfilament bundles in the cytoplasm. The granules contained a very thin halo.

• Journal of Wellness
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• v.7 no.4
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• pp.177-186
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• 2012

The purpose of this study was to find out how Accumulation of Short Duration exercises influence on expression of apoptosis genes in a mouse skeletal muscle. The subjects, ICR-type mice, were divided into three cohorts, Accumulation of Short Duration exercise group, continuous aerobic exercise group, and control group. Accumulation of Short Duration exercise group performed wheel-running for fifteen minutes respectively in the morning and afternoon three times a week. Continuous exercise group performed wheel-running for thirty minutes three times a week. Both split and continuous groups completed the wheel-running trials for sixteen weeks. To identify the difference of apoptosis expression between groups, the data colleted from the skeletal muscle were analysed by one way ANOVA. Analyses of the data revealed that significant differences of apoptosis concentration in both continuous and Accumulation of Short Duration exercise groups, there was a notable differences were observed in control group.

• Korean Journal of Plant Taxonomy
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• v.48 no.2
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• pp.143-152
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• 2018

A comparative study of leaf epidermal microstructures in genus Aruncus (two species, five varieties) was carried out using scanning electron microscopy in order to evaluate their significance in terms of taxonomy. All of the leaves of the taxa studied here were amphistomatic with undulate anticlinal walls, and smooth and flat periclinal walls on both surfaces. The size range of the stomata complex is $8.95-21.97{\times}7.50-16.99{\mu}m$: the largest one was found in Aruncus dioicus var. astilboides (average $18.01{\times}13.47{\mu}m$) and the smallest was measured and determined to be A. gombalanus (average $11.11{\times}8.94{\mu}m$). An anomocytic stomata complex was found in all of the studied taxa. The stomatal frequency on average was $27.54/0.05mm^2$; it is highest in A. gombalanus ($60.4/0.05mm^2$) and lowest in A. dioicus var. acuminatus ($11.6/0.05mm^2$). Two types (short stalked capitate glandular trichome and non-glandular trichome) of trichomes are found in the leaves. The non-glandular trichome was divided into three types based on the presence and degree of development of subsidiary cells. Anomocytic stomata of the hypostomatic type and the distribution pattern of capitate glandular trichomes were the major characters in this genus. The stomata size and frequency, the epidermal cell structure, the trichome type and the distribution pattern may have diagnostic importance among the taxa in the genus. Our leaf micromorphological results provide useful information for the taxonomic revision of the genus Aruncus.