• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.164.2-164.2
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• 2003

Human embryonic stem (ES) cell lines derived from the inner cell mass of human blastocysts have potential to differentiate into any cell types. We have established in vitro neural differentiation of human ES cells. After the formation of embroid bodies (EBs), the differentiating EBs formed neural tube-like rosettes in the presence of basic fibroblast growth factor (bFGF). The rosettes were selectively isolated by the treatment of dispase and cultured in a medium for human neural precursors in the presence of bFGF. (omitted)

• 대한수의학회지
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• 제27권2호
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• pp.253-258
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• 1987

The erythrocytes(E) rosette forming capacity of peripheral blood lymphocytes(PBL) in Korean native cattle was determined with 2-aminoethylisothiouronium bromide hydrobromide(AET) and dextran(Dex)-treated sheep erythrocytes(SRBC). To further standardize the assay, optimum concentration of AET and/or Dex-treatment and incubation time for rosette forming cell(RFC) counts were determined. In untreated SRBC resuspended in the rosetting medium(RPMI 1640 containing 10% FCS), PBL from 7 animals formed low percentage of rosettes($7.8{\pm}6.0%$). Both AET and Dex treatment not only enhanced the rosette formation but also made it easy to enumerate rosettes by increasing numbers of SRBC attached on them. SRBC treated with 0.1M AET for 20 min or 8% Dex formed the highest percentages of rosettes, ($35.7{\pm}6.0%$ and $48.3{\pm}4.7%$, respectively) and were used in subsequent studies. With SRBC treated with 0.1M AET for 20 min and suspended in 8% Dex, the maximum RFC observed were $56.6{\pm}6.8%$ in female and $65.8{\pm}6.3%$ in male and the rates of RFC did not change significantly between 3 and 20 hr incubation time at ${4^{\circ}C}$.

• The Korean Journal of Ceramics
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• 제6권1호
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• pp.74-77
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• 2000

Ta-doped PZT thin films prepared by reactive co-sputtering method could be transformed into single grained perovskite structure utilizing physical etching of Pt bottom electrode. It is found that PZT perovskite phase on damaged (111) Pt electrode by IMD was more easily crystallized than random oriented Pt electrode and less crystallized than (111) Pt electrode. This shows that amorphized Pt electrode surface by IMD process has an effect on crystallization of PZT perovskite phase. 40$\mu\textrm{m}\times40\mu\textrm{m}$ square shape single grain PZT array could be obtained utilizing the difference of incubation time for nucleation of rosettes between ion damaged Pt and (111) oriented Pt electrode. Single grained PZT thin films show low leakage current density of $1\times10^{-7}$ A/$\textrm{cm}^2$ and high break down field of 440kV/cm. The loss of remanent polarization after $10^{11}$ cycles was less than 15% of initial value.

• 천문학회보
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• 제46권2호
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• pp.78.2-78.2
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• 2021

We present high resolution spectroscopic observations of transverse magnetohydrodynamic (MHD) waves in mottles located near the solar disk center. Different from previous studies that used transversal displacements of the mottles in the imaging data, we investigated the line-of-sight (LOS) velocity oscillations of the mottles in the spectral data. The observations were carried out by using the Fast Imaging Solar Spectrograph of the 1.6 meter Goode Solar Telescope of Big Bear Solar Observatory. Utilizing the spectral data of the Hα and Ca II 8542 Å lines, we measure the LOS velocity of a quiet region including the mottles and rosettes that correspond to the footpoints of the mottles. Our major findings are as follows: (1) Alfvénic waves are pervasive in the mottles. (2) The dominant period of the waves is 2 to 4 minutes. (3) From the time-distance maps of the three-minute filtered LOS velocity constructed along the mottles, it is revealed that the transverse waves in the mottles are closely related to the longitudinal waves in the rosettes. Our findings support the notion that Alfvénic waves can be generated by mode conversion of the slow magnetoacoustic waves as was shown in sunspot regions by Chae et al. (2021).

• 한국재료학회지
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• 제28권3호
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• pp.189-194
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• 2018

Porous graphites were synthesized by removing the template in HF after cabothermal conversion for 3 h at $900^{\circ}C$, accompanied by intercalations of pyrolyzed fuel oil (PFO) in the interlayer of Co or Ni loaded magadiite. The X-ray powder diffraction pattern of the porous graphites exhibited 00l reflections corresponding to a basal spacing of 0.7 nm. The particle morphology of the porous graphites was composed of carbon plates intergrown to form spherical nodules resembling rosettes like a magadiite template. TEM shows that the cross section of the porous graphites is composed of layers with very regular spaces. In particular, crystallization of the porous graphite was dependent on the content of Co or Ni loaded in the interlayer. The porous graphite had a surface area of $328-477m^2/g$. This indicates that metals such as Co and Ni act as catalysts that accelerate graphite formation.

• Journal of Chest Surgery
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• 제11권1호
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• pp.12-17
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• 1978

Rifampicin has been widely hailed as the most effective antituberculosis antibiotics since the clinical use of streptomycin, but its immunosuppressive side effect was still annoying problem to be excluded. These studies were carried out to determine the effect of Tuberein-3, tuberculous bacilli extraction with water, on Rifampicin induced T-lymphocytopenia in 5 cases of pulmonary tuberculosis who have never exposed to antimetabolites or steroid compounds. After 2 weeks treatment of Rifampicin, all cases showed T-lymphocytopenia, active $13.0{\pm}2.3$ % and total $43.1{\pm}4.4$%. Followed by another 2 weeks treatment with Rifampicin combined with Tuberein-3, T-lymphocytes in peripheral blood returned to the normal limit, active $21.6{\pm}3.3$% and total $56.3{\pm}1.7$%. Tubercin-3 revealed the restoring activity of suppression of T-lymphocyte rosettes by Rifampicin.

• Journal of Korean Neurosurgical Society
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• 제48권5호
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• pp.461-464
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• 2010

The authors report a 58-year-old woman with low-grade fibromyxoid sarcoma primarily located in the right paravertebral area with extension to L4 neural foramen. The patient complained lower back pain with radiating pain along the posterolateral aspect of the right lower leg. She underwent subtotal surgical removal and Cyber Knife therapy. Diagnosis was made by strikingly characteristic microscopic appearance of a bland spindle cell sarcoma which contained numerous giant collagen rosettes and was also supported by immunohistological findings. The diagnostic image findings and literatures are reviewed and discussed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.281-285
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• 2002

A new method of dynamic contact force measurement between a pantograph and a contact wire is proposed in this paper The method does not require design modification of an original pantograph in order to install sensors such as load cells. Contact forces can be expressed as the sum of vertical shear forces at the support points and inertial forces. Using specially-designed strain gage rosettes. vertical shear forces at the supported points can be measured without noise mixing and thermal effects. In order to obtain contact forces from shear forces, 3 inertial force compansation methods are proposed and compared in this paper. By validation process, the new proposed measurement method is verified to be applicable to the on-line current collection test.

• Journal of Chest Surgery
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• 제54권3호
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• pp.232-234
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• 2021

Ependymomas arise from ependymal cells and can grow at any site in the central nervous system (CNS), as well as in some locations outside of the CNS. The latter is rare, contributing to the frequent misdiagnoses of such cases. Herein, we present the case of a 54-year-old man with a history of lower limb weakness and numbness. Magnetic resonance imaging revealed an extradural, heterogeneously enhanced solid lesion with a regular and well-defined border in the posterior mediastinum. A post-resection histopathological examination revealed tumor-forming perivascular pseudo-rosettes that showed immunoreactivity against glial fibrillary acidic protein, epithelial membrane antigen, and vimentin, as well as a high Ki-67 labeling index. Based on pathological features, a diagnosis of anaplastic ependymoma was established.

• 한국발생생물학회지:발생과생식
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• 제12권1호
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• pp.87-95
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• 2008

만능성 인간 배아줄기세포로부터 확립된 신경줄기세포 또는 신경전구세포는 퇴행성 신경질환 세포치료제로 이용될 수 있는 다양한 종류의 신경세포로 분화 유도될 수 있다. 하지만, 인간 배아줄기세포로부터 신경세포를 생산하기 위한 기술은 아직 많은 장애를 가지고 있다. 인간 배아줄기세포 유래 신경전구세포에서 특징적으로 나타나는 신경관 유사로제트에 대한 이해는 인간 배아줄기세포 신경 분화의 효율을 높이는데 유용한 정보를 제공할 것으로 사료된다. 일반적으로 신경로제트(neural rosette)는 분화 중인 배아체를 부착 배양함으로써 유도하지만, 이 방법은 시간이 걸리고 복잡하다는 단점이 있다. 본 연구에서는 신경로제트가 부착배양을 하지 않고 부유배양으로 형성될 수 있는지 조사하였다. 우선적으로, 배아체 형성 및 신경분화에 인간 배아줄기세포 클럼프(clump) 크기가 영향을 주는지를 조사하였고, 사방 $500\;{\mu}m$ 크기의 인간 배아줄기세포 클럼프가 신경 분화 유도에 가장 효과적임을 확인하였다. 로제트 형성을 유도하기 위해, 사방 $500\;{\mu}m$ 크기의 인간 배아줄기세포 클럼프를 1주일 동안 EB 배양배지에 부유 배양함으로써 균일한 크기의 배아체를 얻은 후, NES 배양 배지에서 부가적으로 $1{\sim}2$주 동안 계속 부유 배양한 결과, $7{\sim}10$일 사이에 신경관 유사 로제트가 형성됨을 확인하였다. 로제트 형성 세포의 신경전구세포로서 특성은 RT-PCR과 면역형광염색법을 이용한 신경전구세포 특이적 마커(vimentivi, nestin, MSI1, MSI2, Sox1, Tuj1) 발현을 통해 확인하였다. 또한, 성장인자를 제외한 NES 배양 배지에서 신경로제트를 $2{\sim}6$주 동안 지속적으로 배양하면 성숙 신경세포로의 말단 분화가 유도됨을 확인하였다. 신경세포 특이적 마커(Tuj1, MAP2, GABA)와 신경아교 특이적 마커($S100{\beta}$, GFAP)는 $2{\sim}3$주 또는 4주 후에 각각 발현이 유도됨을 확인하였고, 희소 돌기아교 특이적 마커(O1과 CNPase)는 $5{\sim}6$주 후에 발현이 증가함을 확인하였다. 본 연구결과는 신경로제트가 부유 배양시스템에서 성공적으로 형성됨을 보여주고 있으며, 이는 인간 배아줄기세포의 신경 분화를 이해하고, 신경전구세포 유도 과정을 단순화하는데 효과적으로 이용될 수 있을 것으로 사료된다.