• Journal of fish pathology
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• v.34 no.1
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• pp.117-121
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• 2021

An ayu (Plecoglossus altivelis) farm in Korea recently experienced an epidemic of vertebral column deformities where about 90% of fry displayed a vertebral column that was grossly opaque along either the cranial part of the column or its entire length. Abnormal fish were lordotic, scoliotic and/or kyphotic about midway down the spine. Examination of serial sections of whole fish showed only histological lesions in the vertebral column and suggested some disturbance in the early development of the vertebral centrum. Such abnormalities included a frayed spinal or notochord sheaths with irregular thickening and compression, mal-absorbed notochord cells, thickening of around cell layer and hypercellularity on both facets of the notochord sheath. No parasites, fungi, or bacteria were detected. While this lesion has only been reported once in the past, this is the first report of histopathological findings.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.37-42
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• 2002

In ascidians, a primitive chordate, maternal cytoplasmic factors and inductive interactions are involved in the specification of cell fate in early embryos. The larval structure of ascidians is relatively simple, and the major mesodermal tissues of the tadpole larva are notochord, muscle and mesemchyme. Formation of muscle cells is a cell-autonomous process, and localized maternal macho-1 mRNA specify muscle fate in the posterior marginal zone of the early embryo. In contrast, inductive influence from endoderm precursors plays important roles in the specification of notochord and mesenchyme fates. FGF-Ras-MAPK signaling is involved in the induction of both tissues. The difference in responsiveness of the posterior mesenchyme and anterior notochord precursors is caused by the presence or absence of the posterior-vegetal egg cytoplasm, respectively. In these cases, directed signal may polarizes the responding cells and cause asymmetric cell divisions that operate in both the anterior and posterior regions.

• Ocean Science Journal
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• v.41 no.4
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• pp.207-210
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• 2006

Leptocephali of the genus Saurenchelys in the family Nettastomatidae were collected from the coastal area of Pohang, Korea and described as the first record from Korean waters. S. stylura and S. lateromaculatus are characterized by two intestinal swellings, the pattern of pigments in the notochord, and by smaller pectoral fins than those of other genus. They are very similar to each other but they are distinguished by the pattern of pigments in the notochord and the intestinal swellings.

• Korean Journal of Ichthyology
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• v.32 no.2
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• pp.97-102
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• 2020

The feeding habits of larval Ammodytes japonicus were examined. A total of 208 individuals were collected by RN80 Net from January to February, 2019 in the coastal waters of Gujora and Mangchi, Geoje, Korea. Range of notochord length of larval A. japonicus was 1.46~8.00 mm and fed mainly on copepods that constituted 99.9% in %IRI. The results of analysis in ontogenetic changes, divided with 3 classes (≤2 mm, 3~4 mm, ≥5 mm, Notochord length), was all classes mainly fed copepods. An opposite relationship was found between the calanoida and cyclopoida. When percentage of calanoida of copepods increased, cyclopoida of copepods decreased.

• Development and Reproduction
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• v.6 no.2
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• pp.77-82
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• 2002

In ascidians, a primitive chordate, maternal cytoplasmic factors and inductive interactions are involved in the specification of cell fates in early embryos. The larval structure of ascidians is relatively simple, and the major mesodermal tissues of the tadpole larva are notochord, muscle, and mesenchyme. Formation of muscle cells is a cell-autonomous process, and localized maternal macho-l mRNA specify muscle fate in the posterior marginal zone of the early embryo. In contrast, inductive influence from endoderm precursors plays important roles in the specification of notochord and mesenchyme fates. FGF-Ras-MAPK signaling is involved In the induction of both tissues. The difference in responsiveness of the posterior mesenchyme and anterior notochord precursors to FGF signaling is caused by the presence or absence of intrinsic factors that inherited from the posterior-vegetal egg cytoplasm, respectively. In these inductions, directed signal polarizes the induced cells and promotes asymmetric cell divisions to produce two daughter cells with distinct fates.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1987.05a
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• pp.24.1-24
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• 1987

척색종은 1856년 루스카(Luschka)에 의해 발견된 이후 1977년까지 약 1000례가 보고되었으며 매년 10∼15례의 새로운 환자가 보고되고 있다. 이는 notochord의 잔유물에서 발생하는 종양으로 척추의 양 끝에서 주로 발생한다. 그러나 경추의 발생은 다른 부위에 비해 드물다. 저자들은 경부 척색종 1례를 경험하였기에 문헌적 고찰과 함께 보고하는 바이다.

• Journal of Chest Surgery
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• v.36 no.9
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• pp.707-710
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• 2003

Chordomas are slowly growing and rare malignant tumors arising from the remnants of the notochord. Furthermore, intrathoracic chordomas presenting as a posterior mediastinal tumor account for only 1∼2％ of all reported chordomas. Incomplete resection of these tumors can lead to local recurrence, distant metastasis and result in a poor outcome, but complete remission can be expected with complete resection and adjuvant radiotherapy. We report a case of thoracic chordoma presenting as a posterior mediastinal tumor which was successfully treated with complete resection and adjuvant radiotherapy without recurrence and distant metastasis for 2 years.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.3
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• pp.368-376
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• 2015

The Feeding habits of larval Liparis tanakae collected from the Nakdong River estuary were studied. L. tanakae [3.8-10.6 mm notochord length(NL)] was a carnivore thatconsumed mainly copepods. Its diet also included small numbers of free-living flatworms (Macrostomida), tintinnids, cladocerans, and polychaetes larvae. To evaluate ontogenetic changes in dietary composition, three size groups were designated: 3-5, 5-7, and >7 mm. Copepods were the most important prey items for all size groups. The smallest size group frequently preyed on polychaete and bivalve larvae, along with copepods. As notochord length increased, the numbers of cladocerans and Macrostomida increased relative to those of polychaete and bivalve larvae.

• Journal of Chest Surgery
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• v.14 no.1
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• pp.95-97
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• 1981

Cystic intrathoracic lesions of foregut origin are now well recognized and account for approximately 10% of lesions presenting as mediastinal tumors. The terminology used to describe mediastinal endodermal cysts has been confused and sometimes ambiguous. The embryological derivation of these lesions has been the cause of much speculation. It Is suggested that these lesions should be classified Into three main categories based on embryology bronchogenic cyst[resulting from a defect of lung budding], Intramural esophageal cyst[true duplication], and enteric cyst[resulting from the split notochord syndrome]. This communication describes a 26 year old man with intramural esophageal cyst who was diagnosed as posterior medlastlnai tumor preoperatively and cured with extirpation of the cyst.

• Journal of Korean Neurosurgical Society
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• v.45 no.4
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• pp.243-245
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• 2009

Chordoma is a rare bone tumor derived from remnants of the notochord. The majority of chordomas involve the sacrum or skull base. We report a rare case of a L4 vertebral body chordoma treated with anterior en bloc vertebrectomy and posterior stabilization. No tumor recurrence was observed at the 5 year follow-up examination.