• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2004년도 춘계학술발표대회
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• pp.199-199
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• 2004

This study was conducted to investigate cytoskeleton alterations during vitrified (Open Pulled Straw method) porcine immature oocytes, to utilize Taxol/sup TM/ (polymerization of tubulin molecules) and Cytochalasin B (CB, depolymerization of actin filaments) during vitrification to stabilize microtubule and microfilaments (MT and MF), and to determine in vitro maturation, fertilization and development of cytoskeletal-stabilized and vitrified porcine immature oocytes. (omitted)

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2002년도 춘계학술발표대회 발표논문초록집
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• pp.48-48
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• 2002

Chimerism has become an important tool for investigating fundamental aspects of early embryonic development and differentiation in mammals for producing transgenic animals. The objective of this study was to evaluate the developmental capacity of chimeric embryos reconstructed with parthenotes and IVF bovine embryos into empty zona pellucida. The MII oocytes were activated by two treatment groups [Group 1, 5 μM inomycin, 5min, ＋ 10 ㎍/㎖ cycloheximide (CHX)/5 ㎍/㎖ cytochalasin B (CCB), 3 h; Group 2, 5 μM ionomycin, 5 min ＋ 1.9 mM 6-dimetylaminopurine (6-DMAP), 3 h]. (omitted)

• 대한음성학회:학술대회논문집
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• 대한음성학회 2007년도 한국음성과학회 공동학술대회 발표논문집
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• pp.146-148
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• 2007

Studies of cry characteristics in the newborn infant were aimed to determine if cry analysis could be succesful in the early detection of the infant at risk for developmental difficulties. Crying presupposes functioning of the respiratory, laryngeal and supralaryngeal muscles. The nervous system controls the capacity, stability, and co-ordination of the movements in these muscles. Hence, the cry provides information about how the Nervous System is functioning. 3 patients(down syndrome, cornelia de lange syndrome, Patent ductus arteriosus) were assessed through a Computerized Speech Lab (CSL). Tests had been chosen to assess Fundamental frequency(mean, maximum, minimum values), Melody contour, NHR, Energy. We compared the data from patients and healthy volunteer. Variations in cry characteristics were documented in a number of medical abnormalities.

• 대한생식의학회:학술대회논문집
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• 대한생식의학회 2007년도 제52차 춘계학술대회 초록집
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• pp.123-123
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• 2007

• 산업기술연구
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• 제16권
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• pp.113-121
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• 1996

In the early developmental stages of robotics,hydraulics played an important role. As the power-to-weight ratio of electric motors increased, they eventually replaced hydraulic actuators in robot manipulators. Recently, however, task requirements have dictated that the manipulator payload capacity increase to accomodate greater payload, greater length, greater reaction forces, and hydraulic actusators are being studied as an effective form of robot actuation again. For efficient control of hydraulic actuators, the knowledge of its dynamic equation is essential. However, the dynamic equation of hydraulic actuators are nonlinear, and the dynamic coefficients are time varying. In this paper, an estimation algorithm of the dynamic coefficients of the hydraulic piston dynamics are formulated. Simulation results are presented to show the possibility of the parameter estimation.

• Molecules and Cells
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• 제43권9호
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• pp.774-783
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• 2020

The lung has a vital function in gas exchange between the blood and the external atmosphere. It also has a critical role in the immune defense against external pathogens and environmental factors. While the lung is classified as a relatively quiescent organ with little homeostatic turnover, it shows robust regenerative capacity in response to injury, mediated by the resident stem/progenitor cells. During regeneration, regionally distinct epithelial cell populations with specific functions are generated from several different types of stem/progenitor cells localized within four histologically distinguished regions: trachea, bronchi, bronchioles, and alveoli. WNT signaling is one of the key signaling pathways involved in regulating many types of stem/progenitor cells in various organs. In addition to its developmental role in the embryonic and fetal lung, WNT signaling is critical for lung homeostasis and regeneration. In this minireview, we summarize and discuss recent advances in the understanding of the role of WNT signaling in lung regeneration with an emphasis on stem/progenitor cells.

• 한국발생생물학회지:발생과생식
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• 제23권2호
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• pp.101-110
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• 2019

Melatonin is a pineal hormone that is synthesized and released at night under the light and dark cycles of a day. Its effects on the reproductive activities have well been established by the administration through various routes in photoperiodic animals. It was also identified in plants and named phytomelatonin. The capacity of the phytomelatonin was investigated in this investigation whether it affects the reproductive function in male golden hamster. As expected, animals housed in long photoperiod (long photoperiod, LP>12.5 hours of lights in a day) had large testes and animals kept in short photoperiod ($$SP{\leq_-}12.5$$ hours of lights in a day) showed remarkably reduced testes. The dietary supplement with melatonin itself induced the complete involution of testes. Pistachios that were reported to contain a large amount of melatonin demonstrated no effects at all in male golden hamsters. These results suggest that dietary supplement containing melatonin-rich foodstuff used in this investigation may not be enough to affect the reproductive endocrine system in male golden hamsters.

• Clinical and Experimental Reproductive Medicine
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• 제19권2호
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• pp.117-123
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• 1992

Development in vitro of 2-cell mouse embryos was examined after appropriate exposure to oviductal milieu to demonstrate biological activity present in the oviducts. ICR and ($C57Bl/6{\times}Balb/c$) $F_1$ hybrid mice were superovulated and mated for the recovery of early embryos. Embryos were recoverd at every 2h intervals from 32h post-hCG(hph) to 56 hph. The proportions of developmental stages were determined in the recovered embryos. Development in vitro of 2-cell embryos was more rapid in $F_1$ hybrid than in ICR, showing high proportions of 4-cell embryo and blastocyst at 120 hph. 100% of blastocyst development was obtained at 38hph in $F_1$ hybrid and at 50 hph in ICR when 2-cell embryos were cultured upto 120hph in vitro. Moreover, in vitro culture of oviducts containing 2-cell embryos in ICR mice for 12h from 34hph to 46hph increased developmental capacity of ICR mouse embryo in vitro. The results indicate that oviductal environment contains substances having mitogenic activity and overcoming early cell block in vitro. The mitogenic activity is effective in vitro as well as in vivo.

• 한국가축번식학회지
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• 제18권2호
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• pp.113-119
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• 1994

To improve nuclear transplantation(NT) efficiency and to produce a large scale genetically identical cloned calves, examined the in vitro development capacity after co-culture of bovine oviductal epithelial cells (BOEC) and granulosa cells in TCM-199 supplemented with 10% fetal calf serum (FCS) with early bovine embryos derived from in vitro matured fertilized(IVM-IVF) oocyte. In addition, the age dependence of IVM oocyte on electro-stimulation and the effective electric voltage on in ivtro development of bovine NT embryos were examined. The results obtained were summerized as follows; 1. The cleavage rates of IVM-IVF bovine embryos in co-culture with bovine oviductal epithelial cells and granulosa cells were not significantly different(P<0.05), but the developmental rate into morula and blastocyst stage were different showing 38.3 and 20.2%, respectively. 2. The activation (82.5%) and development in vitro(8.6%) into later embryo stages of the aging oocytes of 32 hours post-maturation (hpm) were significantly higher than those of 24 hpm at direct current (DC) voltage of 1.5kV/cm, 60$\mu$sec pulse duration and 1 pulse time. 3. The fusion rates of NT eggs of 32 hpm following to different DC voltages from range 0.75 to 1.5kV/cm were not differ, but the developmental rate into morula and blastocyst stages at DC voltages of 0.75 and 1.0kV/cm were higher(11.4 and 12.6%, respectively) than those of 1.5kV/cm(0%). From these results, it can be suggested the optimal culture system for in vitro culture of IVM-IVF bovine embryos is a co-culture system with BOEC in TCM-199 supplemented 10% FCS. The effective time and the DC voltage for activation, electrofusion and in vitro development of NT embryos derived from IVM-IVF bovine embryo are 32hpm and 0.75~1.0kV/cm. But to improve NT efficiency, the advanced research (cell cycle synchronization, micromanipulation, culture system, etc.) is needed.

• Reproductive and Developmental Biology
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• 제31권4호
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• pp.261-265
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• 2007

Insulin, transferrin and selenium (ITS) complex is reported to improve in vitro development of oocytes and embryos. This study was carried out to investigate the effects of ITS during in vitro culture (IVC) of porcine parthenogenetic and nuclear transfer (NT) embryos on subsequent developmental capacity in vitro. The electrically activated oocytes were cultured in Porcine Zygote Medium (PZM-3) with various concentrations (0, 0.1, 0.5, and 1.0%) of ITS for 7 days. Also, the electrically activated reconstructed embryos were cultured in PZM-3 with various concentrations (0, 0.1, 0.5, and 1.0%) of ITS for 6 days. Addition of ITS to culture medium did not affect development of porcine parthenogenetic embryos in vitro. To test the effect of ITS on the in vitro development of porcine NT embryos, factorial experiments were also performed for in vitro maturation (IVM) medium (TCM-199) with or without 1% ITS and culture medium (PZM-3) with or without 0.5% ITS. Addition of 0.5% ITS to culture medium increased (p<0.05) the proportion of NT blastocysts compared with non-treated group. In contrast, addition of 1% ITS to culture medium was ineffective or had a detrimental effect. Also, addition of ITS only to maturation medium increased (p<0.05) the percentage of NT blastocysts formation compared with the control group. In conclusion, addition of ITS to IVM or IVC medium could improve subsequent blastocyst development of porcine NT embryos.