• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2004년도 춘계학술발표대회
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• pp.275-275
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• 2004

To evaluate the potential of the stem cell therapy as a method for prenatal management of spinal open neural tube defect (ONTD), the influence of embryonic stem cells injected into the amniotic cavity on the re-closure capacity of spinal ONTD was investgated. Spinal neural tube was incised open for a length of 6 somites using chick embryos of Hamburger and Hamilton stage 18 or 19. (omitted)

• 한국동물학회지
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• 제30권4호
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• pp.432-444
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• 1987

Very early stage of chick embryo cultivated in the medium containing DLtryptophan by beaker method has been investigated in vitro morphologically using electron microscopy at cellular level and found that the development of tryptophan treated chick embryos corresponding to 18∼66 hrs incubation was impaired and york granule degradation was significantly delayed. It was also found that DNA, RNA and protein biosynthesis of tryptophan treated chick embryo was greatly lowered than those of control group. Conversion of L-tryptophan into serotonin was traced using 14C-L-tryptophan and found that 13.8cA of added radioactivity was recovered from serotonin formed during 18 hrs incubation and the amounts of serotonin formed were depend upon added amount of tryptophan in e99 yolk. It seemed that the serotonin formed from external tryptophan might inhibit the degradation of yolk granule by feedback mechanism, resulting in malformation of chick embryogenesis.

• Applied Microscopy
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• 제26권2호
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• pp.123-136
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• 1996

To investigate the effect of aflatoxin $B_1$, on survival rate and ultrastructure of liver during chick embryogenesis electron microscopic methods were used. After injection of aflatoxin $B_1$ into the yolk, ultrastructural changes in the liver of chicken embryo were observed. The results were as followed. 1. 12-day old chicken embryos were treated with single injection of aflatoxin $B_1$ with the dose of $0.0005{\mu}g,\;0.005{\mu}g,\;0.05{\mu}g,\;0.5{\mu}g,\;2.5{\mu}g,\;5.0{\mu}g$ each. Chicken embryos treated with the dose of $0.5{\mu}g$ of aflatoxin $B_1$ had survival rate of 22%. The embryos treated with $2.5{\mu}g$ of aflatoxin $B_1$ hardly survived. 2. Chicken embryos treated with $0.05{\mu}g$ of afatoxin $B_1$ had hatched in 30%, but once hatched, they all survived. 3. After administration of $0.05{\mu}g$ of aflatoxin $B_1$ into the 12-day old chicken embryo, the electron microscopic studies were examined during development stages. The nuclei of hapatocytes became irregularly shaped and the structures of endoplasmic reticulum were changed to spherical types at 20-day old chicken embryo. Also, mitochondria became to be dilated and severe fibrosis was induced in the cytoplasm. However, the hepatocytes became almost normal in 30-day old young chicken.

• Applied Microscopy
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• 제18권1호
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• pp.60-76
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• 1988

Chick embryos which have received a single injection of the organophosphate compound, malathion (0.1 mg/0.05 ml, 0.5 mg/0.05 ml, 1.0 mg/0.05 ml or 2.0 mg/0.05 ml) via the yolk sac at certain times (2 days, 4 days or 6 days after incubation) have been investigated. After 9 days of incubation, chick embryos were harvested to examine the effects of malathion on the ultrastructure and the acetylcholinesterase(AChE) activity of the developing spinal cord. The effects of simultaneous injection of malathion and nicotinamide were also compared. On ultrastructural findings, neurons in the ventral horn of spinal cord showed to be inhibited in their differentiation by malathion; nuclear irregularity, separation of nuclear membranes, reduction of ribosomal distribution, and cytoplasmic vacuoles were observed. In the younger embryos treated with relatively high doses of malathion, nucleus and cytoplasmic organelles of neurons were severely destroyed, and the neurons were shown to be necrotic. On cytochemical study of AChE by electron microscope, the positive reaction products of AChE were localized at the membranes of nucleus and endoplasmic reticulum of neurons. Inhibition of AChE activity was severe in groups treated with relatively low doses of malathion. Nicotinamide (5.0 mg/0.05 ml) alleviated malathion-induced morphological alterations. In conclusion, it is suggested that malathion changes the ultrastructure and reduces. AChE activity in differentiating neurons, and the severity of which is consistently dose- and age-dependent.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2004년도 제4회 발생공학 국제심포지움 및 학술대회
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• pp.88-88
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• 2004

• 한국가금학회지
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• 제14권2호
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• pp.89-96
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• 1987

본 연구에서는 가금에 있어 세포유전학적 방법을 이용하여 닭 염색체의 분리방법과 G, C-banding에 의한 분염분석 방법을 재고하여 보다 명확한 염색체의 형태적 양상을 제시하였다. 염색체의 분리는 성장중인 초기배아를 이용하므로써 유사분열 중기상을 쉽게 포악할 수 있었으며, 성장 4-5일째의 배아조직으로부터 염색체의 분리는 다소 불편함이 많았다. 가금에 있어 염색체 분리기술중 가장 중요한 것으로 적합한 sample의 채취와 적절한 중기상의 유도, hypotonic 처리에 따른 뚜렷한 형태의 유도, 도말방법 및 염색의 처리과정이다. 또한 보다 명확한 염색체의 분석을 위하여서는 중기 분열상중 초기 중기 상태의 상을 포착함이 바람직하다. G. C-banding 처리를 위해서는 공히 충분하고도 완전히 건조된 air-dried prepration된 sample을 이용하여야 바람직한 결과를 얻을 수 있으며, slide의 보존시간에 따라 band 양상에 많은 차이를 나타낸다. G-banding 양상에 크게 영향하는 요인으로서는 trypsin의 농도, 처리시간, 처리온도가 주된 작용을 하고, Giemsa solution에 사용하는 buffer의 pH도 크게 작용하는 것으로 나타났다. C-banding에 있어서는 Ba(OJ)$_2$의 농도 처리시간, 처리온도가 큰 영향을 미친 바 다소 짧은 시간의 처리가 바람직한 양상을 보이고, 처리전 HCl 처리로서 세포들의 균일성을 가하고, 처리후 철저한 수세가 좋은 결과를 나타내었다. Band 양상의 보다 정확한 해석을 위해서는 densitometer를 이용하므로써 구체적 양상을 분석할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권12호
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• pp.1702-1707
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• 2002

The effects of dark-control (D) and continuous green light (GL) exposure of incubated meat-type breeder eggs (Hybro) on embryonic growth from 5 to 15 days of age, hatching time, hatchability per cent and chick hatching weight were investigated in three consecutive experiments at 33, 38, and 41 weeks of age. A total of 798 eggs were used in this study. Eggs were set in an incubator on trays either in the D or under two tubes of 20-watt green fluorescent light during the first 18 days of incubation. Eggs from both treatments were transferred to the dark hatching compartment at 19 days of incubation. The light intensity was in the range of 1,340 to 1,730 lux at the surface of the eggs. GL incubation of eggs significantly (p<0.01) increased weight (expressed as an absolute value) and daily weight gain of embryos at 11 and continued to 15 days of age, hatchability per cent by 4.8%, reduced dead embryos per cent and chick weight at hatch by 37 and 2%, respectively and accelerated hatching time by about 24 h when compared with the D-control incubation. Chicks hatched at 504 h of incubation had significantly (p<0.01) higher body weight, expressed as an absolute value or as a percentage of egg weight, than those hatched earlier at 456 h of incubation. It was concluded that the GL incubation of meat breeder eggs reduced incubation period and chick weight at hatch and increased embryonic growth and hatchability per cent.

• 생명과학회지
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• 제19권9호
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• pp.1309-1313
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• 2009

내분비교란물질은 일상생활에서 쉽게 발견되는 화학물질이다. Bisphenol A, DDT, benzophenone, phenylphenol 등과 같은 화학물질들은 플라스틱 식품용기나 살충제 등을 통해서 체내에 흡수된다. 내분비교란물질은 내분비계의 정상적인 기능을 방해하기 때문에 인체에 해로우며, 매우 독성이 강한 것으로 알려져 있다. 이러한 내분비교란물질은 심혈관계, 생식계, 신경계뿐만 아니라 인체의 여러 기관에 심각한 타격을 주는 것으로 알려져 있다. 따라서 본 연구에서는 benzophenone과 같은 내분비교란물질이 계배의 발생과정에 영향을 미치고, 계배의 기형을 유도하는지를 알아보고자 하였다. Benzophenone $1{\mu}g$/egg에서 $500{\mu}g$/egg까지를 투여한 후 부화기에서 발생을 유도한 후 각각 6. 9. 12. 15. 18. 21일째마다 확인하였다. 체장의 경우에는 중용량($40{\mu}g$/egg $\sim$ $60{\mu}g$/egg)에서 감소가 시작되는 것을 확인할 수 있었다. 고용량의 실험군($80{\mu}g$/egg $\sim$ $500{\mu}g$/egg)에서는 높은 사망률을 보였으며, 부리 이상이나 안구 기형과 같은 기형의 징후를 발견할 수 있었다. 결론적으로 benzophenone은 계배의 기형을 유도하며, 발생단계에서 심각한 영향을 미치는 것을 확인할 수 있었다.

• 한국환경성돌연변이발암원학회지
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• 제25권1호
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• pp.25-31
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• 2005

The objective was to use MR imaging to provide a template of posterior fossa development during the late stages in the chick embryos. The MR findings were then correlated with histological data. Fourteen normal formalin-fixed embryonic specimens with a gestational age of 14 to 20 days were examined with 1.5 Tesla unit MRl using a conventional clinical magnet and pulse sequences. The MR findings were correlated with the whole-mount histological specimens. Resolution of the morphological features of posterior fossa development in embryos greater than 14 days gestational age was possible. Development of cerebellum, brain stem, 4th ventricle and bony posterior fossa was documented. In the 14-day-old embryos, a premordial cerebellum was visualized in the enlarged bony posterior fossa, and it covered the the roof of the primitive fourth ventricle. The bony posterior fossa grows at the same rate along the supratentorial skull. The supratentorial skull and the rostral part of the brain grows at the same rate. The cerebellum begins to grow later than the rostral part of the brain. In the 19- to 20-day-old embryos, MRl revealed the rapid development of the cerebellar hemispheres, along with an increase in volume manifested by the more typical mushroom-shaped configuration observed in the newly hatched. At this stage, the cerebellum almost completely filled the posterior fossa and covered the entire fourth ventricle. The brain stem grew steadily, but the volume change was too subtle to evaluate. Features of cerebellar histogeneis were beyond the resolution of MRl. However, there were lots of artifacts in the features of the bony posterior fossa. An MR template of normal posterior fossa development would be useful to avoid confusion of normal development with abnormal development and to identify the expected developmental features when provided the estimated gestational age of a embryo.

• Asian-Australasian Journal of Animal Sciences
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• 제8권6호
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• pp.557-562
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• 1995

In this study, characteristics of chick primordial germ cells (PGCs), which is the founder cell of the germline, and gonadal development of the chick embryo between 12hrs and 6 day of incubation were investigated by transverse serial sections of chick embryos under the light microscopic observation. In embryo stage 20 (3 day of incubation), there are a lot of PGCs at the mesenchym, which were moving to the thickened epithelium (gonadal ridge). The PGCs arrive at both right and left gonad primordial in equal number prior to stage 24 (4 day of incubation), but in the following stages, the distribution of the PGCs became asymmetrical. More PGCs colonized the left than the right gonad, but the reason for the unequal distribution of PGCs is uncertain. The PGCs have mostly settled in the gonadal ridge (GR) at 6 day embryo. This study was conducted to investigate characteristics of the PGC migration and gonadal formation and observe the best condition for PGC isolation, culture and to attempt the possibility of the production for transgenic germline chimeras with manipulated PGCs.