• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1288-1294
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• 2009

We have used mutational analysis to identity four genes, MXAN3553, MXAN3554, MXAN3555, and MXAN3556, constituting an operon that is essential for normal fruiting body development in Myxococcus xanthus. Deletion of MXAN3553, which encoded a hypothetical protein, resulted in delayed fruiting body development. MXAN3554 was predicted to encode a metallopeptidase, and its deletion caused fruiting body formation to fail. Inactivation of MXAN3555, which encoded a putative NtrC-type response regulator, resulted in delayed aggregation and a severe reduction in sporulation. Fruiting bodies also failed to develop with the deletion of MXAN3556, another gene encoding a hypothetical protein.

• Journal of Yeungnam Medical Science
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• 제35권1호
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• pp.135-139
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• 2018

There has been a significant increase in the number of multiple pregnancies that are associated with a high risk of preterm delivery among Korean women. However, to date, delayed-interval delivery in women with multiple pregnancy is rare. We report a case of delayed-interval delivery performed 128 days after the vaginal delivery of the first fetus in a dichorionic diamniotic twin pregnancy. The patient presented with vaginal leakage of amniotic fluid at 16 weeks of gestation and was diagnosed with a preterm premature rupture of membranes. Three days later, the first twin was delivered, but the neonate died soon after. The second twin remained in utero, and we decided to retain the fetus in utero to reduce the morbidity and mortality associated with a preterm birth. The patient was managed with antibiotics and tocolytics. Cervical cerclage was not performed. The second twin was delivered vaginally at 34 weeks and 5 days of gestation, 128 days after the delivery of the first-born fetus. This neonate was healthy and showed normal development during the 1-year follow-up period. Based on our experience with this case, we propose that delayed-interval delivery may improve perinatal survival and decrease morbidity in the second neonate in highly selected cases.

• Archives of Pharmacal Research
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• 제25권5호
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• pp.718-723
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• 2002

CKD-602 (7-[2-(N-isopropylamino)ethyl]-(20S)-camptothecin) is a recently-developed synthetic camptothecin analogue and currently under clinical development by Chong Kun Dang Pharm (Seoul, Korea). CKD-602 showed potent topoisomerase inhibitory activity in vitro and broad antitumor activity against various human tumor cells in vitro and in vivo in animal models. This study describes the pharmacodynamics of the immediate and delayed cytotoxicity induced by CKD-602 in a human colorectal adenocarcinoma cell line, HT-29, and its intracellular drug accumulation by HPLC. The present study was designed to address whether the higher activity of CKD-602 with prolonged exposure is due to delayed exhibition of cytotoxicity and/or an accumulation of anti proliferative effect on continuous drug exposure. The drug uptake study was performed to determine whether the delayed cytotoxicity is due to a slow drug accumulation in cells. CKD-602 produced a cytotoxicity that was exhibited immediately after treatment (immediate effect) and after treatment had been terminated (delayed effect). Both the immediate and delayed effects of CKD-602 showed a time dependent decrease in 4IC_{50}$ values. Drug uptake was biphasic and the second equilibrium level was obtained as early as at 24hr, indicating that the cumulative and delayed antitumor effects of CKD-602 were not due to slow drug uptake. On the other hand, CKD-602 treatment was sufficient to induce delayed cytotoxicity after 4hr, however, longer treatment (＞24hr) enhanced its cytotoxicity due to the intracellular accumulation of the drug, which requires 24hr to reach maximum equilibrium concentration. In addition, $C^n$$\times$T=h analysis (n=0.481) indicated that increased exposure times may contribute more to the overall antitumor activity of CKD-602 than drug concentration. Additional studies to determine the details of the intracellular uptake kinetics (e.g., concentration dependency and retention studies) are needed in order to identify the optimal treatment schedules for the successful clinical development of CKD-602.

• Journal of Yeungnam Medical Science
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• 제8권2호
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• pp.24-34
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• 1991

1986년 1월부터 1988년 6월까지 30개월동안 '말이 늦다(언어발달지연)'는 것을 주소로 본원 소아과에 내원한 환아 중 언어발달지연의 진단기준에 부합하였던 52명의 아동을 대상으로 관찰하여 다음과 같은 성적을 얻었다. 1. 환아의 초진시 연령은 2-2.9세군이 16례 (30.8%), 3-3.9세군이 11례(21.2%)로 전체 환아의 반수 이상이 2-3.9세 사이에 내원했다. 2. 성별분포로는 남아가 39례, 여아가 13례로서 3:1의 비로 남아에서 많았다. 3. 원인은 지능발달지연이 28례(53.8%)로 가장 많았으며 그 외 발달성 언어장애가 12례(23.1%), 자폐증이 7례(13.5%)의 순으로 많았다. 4. 동반된 질환들로는 발음장애가 9례(17.3%)로 가장 많았고 사시가 5례(9.6%), 경련성질환이 4례(7.7%)에서 있었다. 5. 치료는 특수교육이 23례(44.2%), 언어치료가 12례(23.1%), 정신과적 자문이 7례(13.5%)에서 행해졌다.

• 대한소아치과학회지
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• 제45권4호
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• pp.484-491
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• 2018

선천적 치아의 결손은 비교적 흔한 치아 발육장애이며 하악 제2소구치의 결손은 치아 결손 중 가장 많이 나타나는 것으로 알려져 있다. 이 연구의 목적은 하악 제2소구치 결손과 연관되어 나타나는 다른 치아의 결손 및 치아의 발육 지연에 대해 조사하는 것이다. 이 연구는 2014년부터 2016년까지 연세대학교 치과대학을 내원하여 파노라마 방사선을 찍은 만 9세-15세의 소아청소년 중 하악 제2소구치 결손이 있는 환자를 대상으로 시행되었다. 하악 제2소구치의 결손을 가진 125명의 환자들 중 다른 치아의 결손은 58명(46.4%)에서 나타났으며 발육이 지연된 치아는 38명(30.4%)에서 나타났다. 이번 연구에서 하악 제2소구치의 결손을 가진 환자는 그렇지 않은 어린이와 비교하였을 때 치아 결손 및 치아 발육지연의 유병률이 높게 나타났다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제5권3호
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• pp.381-391
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• 2005

The level of reliability attained largely depends upon the investment in reliability growth programs during development phase. In order to find the relationship between reliability growth test time and BRTE(basic reliability tasks effectiveness) in a reliability improvement program that minimizes LCC in which contains the reliability growth cost, repair and replacement costs, and spare parts ordering costs in service with given service rate in management policy, the growth rate has been suggested proper LCC versus growth rate. This model employs the reliability growth projection with delayed fixes in avionic equipment based on AMSAA.

• Nuclear Engineering and Technology
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• 제52권3호
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• pp.614-620
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• 2020

In a previous study, delayed hydride cracking (DHC) assessment of pressurized water reactor (PWR) spent fuel during dry storage using the threshold stress intensity factor (K_IH) was performed. However, there were a few limitations in the analysis of the cladding properties, such as oxide thickness and mechanical properties. In this study, those models were modified to include test data for irradiated materials, and the cladding creep model was introduced to improve the reliability of the DHC assessment. In this study, DHC susceptibility of PWR spent fuel during dry storage depending on the axial elevation was evaluated with the improved assessment methodology. In addition, the sensitivity of affecting parameters such as fuel burnup, hydride thickness, and crack aspect ratio are presented.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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• pp.571-574
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• 2000

When fresh concrete is exposed to low temperature, the concrete may suffer from the frost damage at early ages and the strength development may be delayed. To solve such problems of cold weather concreting admixtures called agent for enduring cold climate are developed to prevent the fresh concrete from being frozen at early ages. In this study, the experiments are carried out on several kinds of agent for enduring cold climate to present their performance. According to experimental results, most kinds of agent for enduring cold climate show the strength development in the range $-5^{\circ}C$ of curing temperature, it tends to be delayed at long term maturity without agents for enduring cold climate. while it gains high strength maturity when agents for enduring cold climate is applied.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 추계학술발표회요약집
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• pp.50-50
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• 1998

• Clinical and Experimental Pediatrics
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• 제49권10호
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• pp.1031-1036
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• 2006

In this article, the following topics will be discussed: What is a developmental disability? What are the risk factors for developmental disability? What are the causes of delayed motor development? What are the early manifestations of developmental disability in young infants? What are the goals of early intervention and the forms or types of early intervention services? What are the dynamis of families with a developmentally delayed child? What is the role of a pediatrician for a developmentally disabled child and his or her family?