• Title/Summary/Keyword: 최기형성

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Toxicity Evaluation of Chemicals using Black-spotted Pond Frog Embryos, Rana nigromaculata (참개구리 배아를 이용한 화학물질의 독성평가 연구)

  • Ko, Sun-Kun
    • Korean Journal of Environmental Biology
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    • v.30 no.3
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    • pp.231-237
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    • 2012
  • Toxicity of $Ni^{2+}$ and Tebuconazole were investigated via FETAX (Frog Embryo Teratogenesis Assay-Xenopus) protocol using domestic frog embryos. Embryos of Black-spotted pond frog, Rana nigromaculata, were incubated and toxic effects of $Ni^{2+}$ and Tebuconazole were investigated by probit analysis. As a result, mortality and malformation rates were increased and larval body length was decreased in a dose dependant manner of $Ni^{2+}$ and Tebuconazole. The half maximal effective concentration ($EC_{50}$) of $Ni^{2+}$ and Tebuconazole were 0.07, $12.7mg\;L^{-1}$, respectively and the half maximal lethal concentration ($LC_{50}$) of $Ni^{2+}$ and Tebuconazole were 4.2, 39.1, respectively. The teratogenic index (TI) were 61.4 in $Ni^{2+}$ and 3.1 in Tebuconazole, respectively. These results reveals that $Ni^{2+}$ and Tebuconazole suppress the development of Black-spotted pond frog embryos at the low concentration as showing teratogenic effects in other assay system. Therefore, teratogen assay system using the Rana nigromaculata embryos could be useful as a tool to evaluate the toxicity of the pollutants in environment.

A case of recurrent respiratory infection resulting from a congenital anomaly of the bronchial tree tracheal bronchus (반복적인 호흡기 감염을 가진 환아에서 진단된선천성 기도 기형, 기관기관지 1예)

  • Choi, Ah-Reum;Choi, Sun-Hee;Kim, Seong-Wan;Sung, Dong-Wook;Rha, Yeong-Ho
    • Clinical and Experimental Pediatrics
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    • v.51 no.6
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    • pp.660-664
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    • 2008
  • The term tracheal bronchus refers to an abnormal bronchus that comes directly off of the lateral wall of the trachea (above the carina) and supplies ventilation to the upper lobe. Tracheal bronchi occur almost exclusively on the right trachea and are associated with other congenital anomalies. In addition, tracheai bronchus may be related to other inflammatory conditions with persistent wheezing, such as recurrent pneumonia, chronic bronchitis and bronchiectasis, which is a result of the relatively poor local drainage of the involved bronchi. An infant with recurrent wheezing is likely to be a challenge for a clinician in the evaluation of the etiology of airway obstruction and in the differential diagnosis of wheezy breathing. The authors report a case of an 8-month-old female infant with a ventricular septal defect, who presented with stridor and recurrent respiratory infection and finally was finally diagnosed with a tracheal bronchus using computed tomography and a bronchoscopy. Therefore, tracheal bronchus should be included in the differential diagnosis of any child who presents with chronic or recurrent respiratory tract symptoms such as coughing, wheezing, stridor and recurrent respiratory infection, particularly in children with other congenital deformities.

Comparison of the recovery behavior of a transformer type SFCL and a flux-coupling type SFCL (변압기형과 자속결합형 초전도 한류기의 회복성능 비교)

  • Kim, Deog-Goo;Choi, Hyo-Sang;Cho, Yong-Sun;Park, Hyoung-Min;Jung, Byung-Ik;Ha, Kyoung-Hun;Choi, Soo-Geun
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.2166-2167
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    • 2011
  • 급격히 증가해온 사고전류로부터 전력망을 보호하기 위한 해결책으로 초전도 한류기가 제시되어 왔다. 초전도체의 영저항 특성을 이용한 초전도 한류기는 정상상태시 무손실로써 동작하기 때문에 전력 공급의 효율성을 저하시키지 않는 장점이 있다. 이러한 초전도 한류기를 전력망에 적용하기 위해서는, 용량증대의 문제가 우선적으로 해결되어야 하는 바, 초전도 소자의 직 병렬 연결과 더불어 변압기를 이용한 여러 타입의 초전도 한류기가 제시 및 연구되어 왔다. 본 논문에서는 변압기형 초전도 한류기와 자속결합형 초전도 한류기를 구성하여 단락사고 발생시 각 초전도 한류기의 회복성능을 비교 분석 하였다. 각 초전도 한류기는 사고전류 제한 동작특성에 따라 회복시간의 차이를 보였다.

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Teratogenicity of phenytoin in ICR mouse and antiteratogenic effect of dimethyl sulfoxide (ICR마우스에서 phenytoin의 최기형성 및 dimethyl sulfoxide의 항최기형 효과)

  • Lee, Jae-kwon;Lee, Chang-eop;Lee, Mun-han;Ryu, Pan-dong;Cho, Myung-haing;Sung, Ha-jung;Park, Jin-bong
    • Korean Journal of Veterinary Research
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    • v.34 no.4
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    • pp.821-831
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    • 1994
  • Phenytoin(PHT), a commonly prescribed anticonvulsant, has been known as a teratogen in experimental animals and human. However, PHT has strain-specific teratogenic effects for mice and human. Dimethyl sulfoxids(DMSO) has been known to antagonize the teratogenic effects of secalonic acid D, a toxic mold metabolite that has similar teratogenic effects to PHT. Therefore, this study was performed to examine the embryopathic effects of PHT in terms of treatment period and the antiteratogenic effect of DMSO in ICR mice. PHT(75mg/kg, BW) was administered intrapetitoneally on day 10, 10-11 and 10-12 of gestation with or without DMSO(2ml/kg, BW), and the fetal malformation was observed on day 18. Major malformation of fetuses treated with PHT on day 10, 10-11 and 10-12 of gestation was cleft palate, and the percentages of fetus with cleft palate were 14.5%, 31.7% and 51.7%, respectively. Also, there was a significant decrease of cleft palate from 51.7% in PHT alone group to 30.8% in PHT plus DMSO group. Our findings suggest that cleft palate is one of major malformation by PHT treatment in ICR mouse and DMSO has strong antiteratogenic effect.

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Culture of Rat Embryos During Early Organogenesis (초기 기관형성기중 랫트배자의 배양에 관한 연구)

  • Chin Kang;Lee, You-Mie;Rheu, Hang-Mook
    • Environmental Analysis Health and Toxicology
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    • v.6 no.1_2
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    • pp.71-82
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    • 1991
  • Rat embryos were cultured out of the mother from the head-fold stages, 9.5 days to 11.5 days during which they start to develop the brain, eyes, ears and cardiovascular system etc. We principally did the basic experiment in order to establish the best condition of the rat whole embryo culture in our laboratory. The temperature in the culture system was maintained 37$^{\circ}C$$\pm$0.2$^{\circ}C$ for 48 hrs. The culture was carried out in humidified atmosphere of the air, intially, the bottles were equilibrated with 5% $O_2$,5% $CO_2$, and 90% $N_2$gas mixture. After 22 or 24 and 29 or 30 hrs the cultures were reequilibrated with 20% $O_2$, 5% $CO_2$,75% $N_2$and 40% $O_2$, 5% $CO_2$, 55%$N_2$respectively. Various types of sera were tested and for the purpose of minimizing the quantity of rat serum, artificial medium was also tried and it was determined that rat serum supported normal growth over a period of 48 hrs, based on total growth analysis and structural comparisons with in vivo specimens.

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The effect of thiamin on fetal growth and development in CD-1 mice exposed with mercury for the gestation period (임신 중 수은을 섭취한 CD-1 마우스 태아의 성장발육과 기형발생에 미친 티아민의 효능 평가)

  • Kim, Jin-suk;Choi, Seok-wha
    • Korean Journal of Veterinary Research
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    • v.34 no.1
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    • pp.69-75
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    • 1994
  • Pregnant CD-1 mice were exposed to methylmercury in the drinking water at concentration of 20ppm with subcutaneous treatment of thiaminHCl(vitamin $B_1$) (100mg, 200mg or 300mg/ kg b.w.) or BAL(5.0 mg/kg b.w.) under the alone or combined base at the therapeutic agents from day 6 to 15 of gestation. Fetal growth parameters, including body weight and crown-rump length in the mice exposed to mercury, were reduced as placental weight compared to those in the control group(no treatment). The incidence of dead fetuses/resorption and malformed fetuses(especially cleft palate) was also increased even in the group treated with thrapeutic agents as well as in the mercury only treated group. However, all kinds of alteration indicated above, possibly induced by mercury, reduced/or decreased significantly compared to those of control. A subtle indication of maternal toxicity was noted in most experimental animals as evidenced by decreased water consumption and increased relative liver weight. The present study confirmed that methylmercuric chloride is embrytoxic and teratogenic in CD-1 mice when administered during organogenesis and that thiamin administration may have therapeutic application for the treatment or prevention against of deleterious effects induced by mercury during gestation period.

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Establishment of Short-Term Teratogenicity Study for Detecting Developmental Toxicity Induced by Gamma Radiation (방사선의 발생독성 검색을 위한 단기 최기형성 시험법의 확립)

  • 김종춘;김성호;신동호;신진영;김세라;이해준;박승춘;조성기;이윤실
    • Toxicological Research
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    • v.20 no.2
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    • pp.117-122
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    • 2004
  • The present study was carried out to establish a short-term teratogenicity study for detecting developmental toxic potential induced by gamma radiation in ICR mice. Pregnant mice were exposed at dose levels of 0, 0.5, 1, 2, or 4 Gy on gestational day 8.5. All dams were subjected to caesarean section on gestational day 10.5 and their embryos were examined for growth, differentiation, and morphological abnormalities. An increase in the number of resorption was found at 4 Gy in a dose-dependent manner. Dose-dependent decreases in the developmental score of yolk sac circulation and olfactory system at above 1 Gy, in the number of somite pairs and developmental score of allantois, optic system, and maxillary process at above 2 Gy, and in the all growth and developmental parameters examined at 4 Gy were found. Various types of morphological abnormalities were seen at dose levels of 0.5 Gy or greater. Characteristic malformations induced by gamma radiation were abnormal axial rotation, hematoma, craniofacial hypoplasia, open neuropore, shortened prosencephalon, kinked somites, irregular somites, swelling, hydropericardium, absent branchial bar, and absent limb bud. Morphological alterations such as hematoma, craniofacial hypoplasia, open neuropore, and kinked somites were noted even in the lowest dose (0.5 Gy). These results indicated that the short-term teratogenicity study established in this study can be a useful tool for not only detecting the developmental toxic potential induced by gamma radiation, but also screening radio-protective agents in ICR mice.

A Teratogenicity Study on Original Woo-Whang-Chung-Sim-Won in Rats (원방우황청심원의 랫드 최기형성에 관한 연구)

  • 한순영;박귀례;신재호;김판기;권석철;장성재
    • Toxicological Research
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    • v.13 no.4
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    • pp.331-338
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    • 1997
  • A teratogenic study on Original Woo-Whang-Chung-Sim-Won was carried out in SpragueDawley rats. Original Woo-Whang-Chung-Sim-Won suspended in distilled water was administered to pregnant dams by oral gavage during organogenesis period (from 7th to 17th day of gestation) at daily doses of 1/9, 1/3 and I pill/kg. About two-thirds of dams were sacrificed at 20th day of gestation to scrutinize the pregnant performances and fetal development, and the remaining dams were allowed to deliver. The growth, reflex, behaviour and reproductive function of F1 offsprings were examined. There was no treatment-related difference in body weight, food consumption and necropy findings of dams. No gross, skeletal and visceral abnormalities was observed in F1 fetuses from dams treated with Original Woo-Whang-Chung-Sim-Won. F1 offsprings did not show any treatment-related difference in growth, reflex, behaviour and reproductive peuformance. At caesarean section of F1 dams, no growth retardation and gross abnormality was observed in F2 fetuses. In conclusion, Original Woo-Whang-Chung-Sim-Won did not show any potential teratogenic activity in rats.

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Study on Hybrid Type Cloud System (하이브리드형 클라우드 시스템에 관한 연구)

  • Jang, Jae-Youl;Kim, Do-Moon;Choi, Chul-Jae
    • The Journal of the Korea institute of electronic communication sciences
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    • v.11 no.6
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    • pp.611-618
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    • 2016
  • The suggested paper studies communications network and system technology, designing data to sync to both USB memories and cloud storages at the same time, which would allow users to safely keep and manage data even in case of network troubles, affecting cloud storages, and/or loss of physical USB memories, resulting in lost data in the physical memory. The need of secure data management policy for cloud storage users form the basis of this study, offering solutions to network failures and loss of physical storage by creating hybrid cloud system. To provide convenience to windows users, the UI design should integrate that of windows explorer to maximize security and convenience.