• Title/Summary/Keyword: Morphological features

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MOLECULAR CONTROLS OF EPIDERMAL GROWTH AND DIFFERENTIATION: TRANSFORMING GROWTH FACTORE

  • Son, Youngsook;Fuchs, Elaine
    • Toxicological Research
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    • v.7 no.2
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    • pp.209-229
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    • 1991
  • In the epidermis of skin, a fine balance exists between proliferating progenitor cells and terminally differentiating cells. We examined the effects of TGF-betas and retinoic acid (RA) on controlling this balance in normal human epidermal keratinocytes cultured under conditions where most morphological and biochemical features of epidermis in vivo are retained. Our results revealed marked and pleiotropic effects of both TGF-beta and RA on kerationcytes. In contrast to retinoids, TGF-betas acted on mitotically active basal cells to retard cell proliferation.

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Nosocomial submandibular infections with dipterous fly larvae

  • Joo, Chong-Yoon;Kim, Jong-Bae
    • Parasites, Hosts and Diseases
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    • v.39 no.3
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    • pp.255-260
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    • 2001
  • In September 1998, a case of nosocomial cutaneous myiasis caused by Lucilia serocata (Meigen, 1826) in a 77-year-old male was found. The patient had been receiving partial maxillectomy due to the presence of malignant tumor on premaxilla. This is the first verified case involving Lucilia sericata in Taegu, Korea. In the present paper, the salient morphological features of the third instar larvae involved have been studied.

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Role of linked color imaging for upper gastrointestinal disease: present and future

  • Sang Pyo Lee
    • Clinical Endoscopy
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    • v.56 no.5
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    • pp.546-552
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    • 2023
  • Techniques for upper gastrointestinal endoscopy are advancing to facilitate lesion detection and improve prognosis. However, most early tumors in the upper gastrointestinal tract exhibit subtle color changes or morphological features that are difficult to detect using white light imaging. Linked color imaging (LCI) has been developed to overcome these shortcomings; it expands or reduces color information to clarify color differences, thereby facilitating the detection and observation of lesions. This article summarizes the characteristics of LCI and advances in LCI-related research in the upper gastrointestinal tract field.

Taxonomic Notes on Acrosorium Dabellatum and A. venulosum (Delesseriaceae, Rhodophyta) in Korea

  • Kim Young Sik;Choi Han Gil;Nam Ki Wan
    • Fisheries and Aquatic Sciences
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    • v.4 no.2
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    • pp.93-97
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    • 2001
  • Morphological features of the two Korean Acrosorium species, A. flabellatum Yamada and A. venulosum (Zanardini) Kylin (Delesseriaceae, Rhodophyta) are described based on specimens collected from several localities along the coasts of Korea. Acrosorium flabellatum is easily distinguished from other Acrosorium species in lacking rhizoids in branchlets for attachment to substratum. The flabellate branching is also characteristic for this species. By contrast, Acrosorium venulosum is distinct from others in having the unique hooked branchlets. Taxonomic features found in the Korean Acrosorium species are compared, and a key to the species is provided based on this and previous data.

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Fine Needle Aspiration Cytology of Hepatoblastoma -Report of Two Cases- (간아세포종의 세침흡인 세포학적 소견 -2예 증례보고-)

  • Park, Young-Nyun;Lee, Kwang-Gil;Park, Chan-Il
    • The Korean Journal of Cytopathology
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    • v.1 no.1
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    • pp.98-102
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    • 1990
  • Hepatoblastoma (HB) is a rare embryonic malignant tumor of the liver. Most morphological studies on HB have limited to the histological characteristics and only 3 cases of HB have been described in the cytology literature. We present 2 cases of HB occurring in children aged 1 year and 3 years, respectively. The distinctive cytologic features of fine needle aspiration of HB were clusters of tumor cells showing acinar and trabecular pattern, smaller tumor cells with a high nuclear-cytopalsmic ratio and hyperchromatic nuclei having prominent nucleoli, and the presence of extramedullary hematopoiesis and osteoid material. These features were also found in the cell block and the biopsy specimen, and appeared very useful in the differentiation of HB from hepatocellular carcinoma.

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Dictyota bartayresiana, a Brown Algal Species Newly Recorded in Korea

  • Kang, Pil Joon;Nam, Ki Wan
    • Korean Journal of Environmental Biology
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    • v.35 no.3
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    • pp.335-340
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    • 2017
  • A marine brown alga was collected from Geoje, located on the southern coast of Korea. This species shares the generic features of Dictyota and is morphologically characterized by the combined features of erect or prostrate thallus with smooth margin, dichotomous to subdichotomous branches not twisted at the terminal part, absence of surface proliferations, 1-3 cell layered cortex and unilayered medulla, and lack of involucrum in sporangia subtended by a single stalk cell. In a phylogenetic tree based on rbcL sequences, this species nests in the same clade with Dictyota bartayresiana. The genetic distance between both sequences within the clade was calculated as 1.2%, considered to be within the intra-species range for the genus. Based on these morphological and molecular analyses, this Korean alga is identified as D. bartayresiana described originally from the West Indies. This is the first record of D. bartayresiana in Korea.

First Record of Paramenophia platysoma (Copepoda: Harpacticoida: Thalestridae) from Korea, with Notes on the Morphology of the Genus

  • Kim, Jong Guk;Choi, Hyun Ki;Yoon, Seong Myeong
    • Animal Systematics, Evolution and Diversity
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    • v.33 no.3
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    • pp.176-188
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    • 2017
  • Paramenophia platysoma (Thompson and Scott, 1903) is newly reported from Korean waters based on the materials collected from several seagrass and algal bed habitats. The Korean materials of P. platysoma in the present study coincide well with the original description of the species with respects to the characteristic features of the first, fourth, and fifth legs, and in most respects to P. platysoma sensu $Gam{\hat{o}}$ (1969) reported from Japan except for the antennary exopod. However, they show some differences to P. platysoma sensu Pallares (1973, 1975) reported in Argentina, in terms of the morphology of the fifth leg in females and the second leg in males. Detailed description and illustrations of P. platysoma are provided for both sexes. The morphological features of Paramenophia species are discussed and a key to the species of genus is provided.

COMMON FEATURES OF SPATIAL ORIENTATION OF DISK GALAXIES IN THE COMA AND VIRGO CLUSTER

  • Hul F. X.;Wu G. X.;SU H. J.;LIU Y. Z.;YUAN Q. R.
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.53-54
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    • 1996
  • Based on the database of 128 disk galaxies (66 SO, 62 S and Irr) mailnly compiled from Kent and Gunn (1982) and Doi et a1.(1995) which is complete down to m < 15.6 mag within a radius of $3^{\circ}$, the orientation of spin vectors of disk galaxies of the Coma cluster has been analyzed. The results confirm the morphological dependence of the orientation of disk galaxies found from the analsis of the Virgo cluster. Common features of orientation of disk galaxies of both clusters are outlined.

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Cuticle Micromorphology of Korean Gymnosperms I. Cycadaceae, Ginkgoaceae, Taxaceae and Cephalotaxaceae

  • Sung Soo Whang
    • Journal of Plant Biology
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    • v.38 no.2
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    • pp.181-193
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    • 1995
  • Cuticle micromorphology of four families of Korean gymnosperms, Cycadaceae, Ginkgoaceae, Taxaceae, and Cephalotaxaceae, were studied with scanning electron microscopy. The outer and inner features of abaxial and adaxial cuticles were described in details; the absent or present of Florin ring, orifice, trichome, and plug and their shape, the shape and periclinal and anticlinal wall sculpture of epidermal cells, the shape of cuticular flange of epidermal cell, guard cell, and subsidiary cell, the number of stomatal bands and rows, and stomatal apparatus including the shape of polar extension, number of subsidiary cells, the sculpture of guard cell and subsidiary cell. Most of these features have not been sufficiently substantiated by the previous reprots. Furthermore, all the species investigated showed distinctive cuticle morphology with morphological and taxonomical informations.

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