• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.59-59
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• 2003

• Korean Journal of Animal Reproduction
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• v.27 no.2
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• pp.163-167
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• 2003

This study was carried out to get a fundamental information fur improvement of reproductive performance in gilt. We investigated the effects of breeds on body weight, age, body length, wither's height, girth and backfat thickness, and the serum concentrations of estradiol-17$\beta$, cortisol and progesterone at first estrus and mating of gilts. A total of 47 gilts of Duroc, Landrace and Yorkshire, produced at Livestock Experiment Station, Chungnam Livestock Sanitation Research Institute from 2000 through 2002, were used for this experiment. Body weight, age and girth of Duroc at first estrus and mating were higher than those of Landrace and Yorkshire. There were no differences on body length among the three breeds at first estrus and mating. Wither's height of Duroc and Yorkshire at first estrus and mating was higher than that of Landrace. Backfat thickness of Yorkshire was thinnest among the three breeds at first estrus, but there were no differences on backfat thickness among the three breeds at first mating. Serum estradiol-17$\beta$ concentration of Landrace (45.0 pg/ml) at first estrus was higher than that of Yorkshire (27.4 pg/ml) and Duroc (21.8 pg/ml), but there were no differences on estradiol-17$\beta$ concentration (from 18.5 to 31.9 pg/ml) among the three breeds at first mating. Serum cortisol concentration of Duroc at first estrus and mating was higher than that of Landrace and Yorkshire. There were no differences on serum progesterone concentration among the three breeds at first estrus and mating of gilt.

• Korean Journal of Animal Reproduction
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• v.16 no.4
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• pp.377-385
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• 1993

This study was taken to examine correlationships between ehdocrine changes such as estradiol-17$\beta$, progesterone, T4 and T3 and serum components concentrations of female Oreochromis niloticus living in 0$\textperthousand$, 10$\textperthousand$, 20$\textperthousand$, and 30$\textperthousand$ salt concentrations, respectively. The results obtained in these experiments were summarized as follows. Correlation coefficients of serum albumin and thyroxine were ＋0.907 and ＋0.611 in 10$\textperthousand$ and 20$\textperthousand$, respectively. In 30$\textperthousand$ salinity, serum BUN and other 3 kinds of hormones showed all negative correlation coefficients. Correlation coefficients of serum estradiol-17$\beta$ with calcium and cholesterol in 20$\beta$ were ＋0.624, ＋0.733, respectively. Correlation coefficient between serum triglycerides and thyroxine in 30$\beta$ was ＋0.989.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.311-311
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• 1994

어류를 이용한 화학물질의 독성평가 방법 및 기작에 관한 연구의 일환으로 암수동체 점박이 송사리에서 N-methyl-N'-nitrosourea (NMU)에 의해 유발되고 여성 호르몬의 일종인 17$\beta$-estradiol (E$_2$)에 의해 촉진유도된 갑상선 종양의 조직학적 특징을 광학 현미경과 전자현미경 수준에서 조사하였다. 본 연구에서 유도된 갑상선 종양은 광학현미경 수준에서 포유류와 유사하게 hyperplasia형, medullary형, papillae형, follicle형, 그리고 papillae형과 follicle형의 혼합형으로 구분할 수 있었다. 전자현미경 관찰 결과 미토콘드리아의 변형, 핵의 크기 증가 및 핵내 세포질 봉입체 함입등의 특징이 인간을 포함한 포유류의 양상과 매우 유사하였다. 이상의 결과는 본 종이 신약의 갑상선 종양유발성을 검증하는데 매우 유용한 실험동물 모델임을 시사한다.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.135-135
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• 2001

Mating behavior and reproductivity of male fish were studied as an in vivo screening method of endocrine disruptors. Male medaka (Oryzias latipes) were exposed to 17$\beta$-estradiol at nominal concentrations of 2 and 20 $\mu\textrm{g}$/L for 14 days.(omitted)

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2005.10a
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• pp.64-65
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• 2005

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.64-65
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• 2005

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.153-158
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• 1998

Effects of cyclic (c) AMP and G-protein related reagents (3-isobutyl-l-methyxanthine (IBMX), Forskolin (FSK), cholera toxin (CTX), and pertussis toxin (PTX≫ on estradiol-17$\beta$ induced vitellogenin (VTG) induction were examined in primary hepatocyte cultures in rainbow trout Oncorhynchus mykiss. The addition of IBMX, FSK, or CTX to the incubation medium markedly increased VTG production, while PTX was not effective in stimulating the production. It is well known that cAMP regulates phosphorylation and dephosphorylation through mediation of protein kinase A. These results suggest that VTG production is highly dependent on cAMP state in hepatocytes because of its highly phosphorylated nature.

• Development and Reproduction
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• v.17 no.4
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• pp.441-449
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• 2013

Recent study showed that T cells in the immune organs and peripheral blood are influenced by estradiol, leading to a dysfunction of the immune system. However, little is known about the thymic-gonadal relationship during the estrous cycle in mouse. Therefore, the purpose of this study was to elucidate the mechanism by which a change in estradiol levels during the estrous cycle regulates the development of T cells in the mouse thymus. Six-week-old ICR mice were used and divided into four groups, including diestrous, proestrous, estrous, and metestrous. We first confirmed that ER-${\alpha}$ and - ${\beta}$ estrogen receptors were expressed in thymic epithelial cells, showing that their expression was not different during the estrous cycle. There was also no significant difference in thymic weight and total number of thymocytes during the estrous cycle. To determine the degree of thymocyte differentiation during the estrous cycle, we analyzed thymocytes by flow cytometry. As a result, the percentage of CD4+CD8+ double-positive (DP) T cells was significantly decreased in the proestrous phase compared to the diestrous phase. However, CD4+CD8- or CD4-CD8+ (SP) T cells were significantly increased in the proestrous phase compared to the diestrous phase. In addition, the percentage of CD44+CD25- (DN1) T cells was significantly decreased in the estrous phase compared to other phases, whereas the percentages of CD44+CD25+ (DN2), CD44-CD25+ (DN3), and CD44-CD25- (DN4) were not changed during the estrous cycle. These results indicate that the development of thymocytes may arrest in the DP to SP transition stage in the proestrous phase displaying the highest serum level of estradiol. This study suggests that a change in estradiol levels during the estrous cycle may be involved in the regulation of thymocyte differentiation in the mouse thymus.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.1
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• pp.33-39
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• 2007

Objective: The objective of this study was to investigate whether serum levels of vascular endothelial growth factor (VEGF) measured at ovulation triggering day reflect ovarian response in intrauterine insemination (IUI) cycles. Methods: Forty-nine fertile women who undergoing superovulation and IUI were included. Superovulation was performed using clomiphene citrate (100 mg/d on day 3$\sim$7) in combination with human menopausal gonadotropin (150 IU every other day starting on day 5). Serum samples were obtained on the day of hCG administration and the levels of VEGF-A and estradiol were measured. The numbers of mature follicle $\geq$17 mm in diameter were also counted. Results: Serum VEGF-A levels did not correlate with the numbers of mature follicle count nor serum estradiol levels. Serum estradiol level was positively associated with mature follicle count. Serum VEGF-A levels tended to be lower in women with mature follicle count less than three or women with more than five. Conclusion: Our results indicate that serum VEGF-A levels do not have an association with superovulation outcome in IUI cycles. However, a tendency of lower VEGF-A level in poor and high responder suggests that those with extreme response to superovulation may be related with abnormal angiogenesis. Further studies should be warranted in larger populations.