• Biomolecules & Therapeutics
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• v.24 no.2
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• pp.109-114
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• 2016

In Drosophila, rhomboid proteases are active cardinal regulators of epidermal growth factor receptor (EGFR) signaling pathway. iRhom1 and iRhom2, which are inactive homologs of rhomboid intramembrane serine proteases, are lacking essential catalytic residues. These are necessary for maturation and trafficking of tumor necrosis factor-alpha (TNF-${\alpha}$) converting enzyme (TACE) from endoplasmic reticulum (ER) to plasma membrane through Golgi, and associated with the fates of various ligands for EGFR. Recent studies have clarified that the activation or downregulation of EGFR signaling pathways by alteration of iRhoms are connected to several human diseases including tylosis with esophageal cancer (TOC) which is the autosomal dominant syndrom, breast cancer, and Alzheimer's disease. Thus, this review focuses on our understanding of iRhoms and the involved mechanisms in the cellular processes.

• Toxicological Research
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• v.16 no.3
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• pp.229-238
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• 2000

The purpose of reproductive toxicity studies is to evaluate all effects resulting from paternal or maternal exposure that interfere with conception, development, birth, and maturation of offspring. In 1966, the US Food and Drug Administration (US FDA) published guidelines for a three-segment study for drug testing to examine adverse effects on fertility and pregnancy. Three segments were proposed: Segment I, Study of Fertility and General Reproductive Performance, to provide information on breeding, fertility, nidation, parturition, neonatal effects and lactation: Segment II, Teratological study, to provide information on embryo toxicity and teratogenicity: and Segment III. perinatal and Postnatal Study, to provide information on late fetal development, labour and delivery, neonatal viability, and growth and lactation. The classic guideline is still used to this day with only monor modification throughout the world. In the present review, the principles and methods of reproductive toxicity studies are discussed with special attention given to scientific issues.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.2
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• pp.182-187
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• 2010

The aim of this experiment was to evaluate the levels of hormones (progesterone, IGF-I and IGFBP-3) in blood plasma, growth, carcass traits and their interactions of sexually immature (n = 18) and sexually mature (n = 17) gilts. To calculate average daily weight gain (ADG), gilts were individually weighed at the beginning of the trial and at slaughter (110${\pm}$10 days old). Blood concentrations of progesterone, IGF-I and IGFBP-3 were determined by RIA. The right hot carcass sides were dissected and the individual basic parts from carcasses were weighed to record the carcass traits. IGFBP-3, ADG and carcass traits were not affected by pubertal maturation. Compared to sexually immature gilts, mature gilts had higher blood concentrations of progesterone and IGF-I. High correlations were noted between levels of some hormonal substances, productive performance and carcass traits of sexually immature and mature gilts.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.2
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• pp.179-187
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• 1998

In mammal, lots of follicles start simultaneously their growth but only a few oocytes are ovulated in every sexual cycles. Most of matured and grown oocytes are destined to degenerate by atresia. However, the molecular and physiological mechanisms are not elucidated yet. The present study was designed to establish an induction method of follicular atresia with ketamine or pentobarbitone and evaluate the effect of these anesthetics on oocyte maturation and granulosa cell apoptosis of the mouse ovarian follicle. The percentages of degenerated oocyte and apoptotic granulosa cell in ketamine treated groups were significantly higher than that in controls (58.9% vs 33.5%, p<0.01, degeneration; 44.9% vs 26.6%, p<0.01, apotosis). Futhermore, it was revealed that the concentrations of progesterone in both groups were markedly higher than that in control. In cunclusion, it is considered that ketamine induce an atresia as pentobarbitone, and may be useful for inducing follicular atresia.

• YAKHAK HOEJI
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• v.24 no.3_4
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• pp.143-150
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• 1980

The effect of ginseng saponin on chick embryonic dorsal root ganglia organ culture and brain, spinal cord, muscle dissociation cultures was studied. The fiber outgrowth in explanted chick embryonic dorsal root ganglia was markedly induced by water and alcohol extracts of ginseng, total ginseng saponin, protopanaxadiol and protopanaxatriol glycosides as well as ginsenosides R/sub b1/, R/sub d/, R/sub 0/+R/sub a/+R/sub b1/, and R/sub b2/+R/sub c/+R/sub e/ mixtures. The life span of the cultured chick embryonic dorsal root ganglia and potentiation of nerve cell density were also observed with all of these ginseng saponins. The effect of ginseng saponin on chick embryonic dorsal root ganglia organ culture was more marked in the absence of the chick embryonic extract which was known to contain nerve growth factor-like material in the culture media. However, the ginseng saponin did not influence the cultured central nervous system such as brain and spinal cord cells and cultured skeletal muscle cells with respect to the morphological changes, maturation and life span of these cells.

• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1154-1158
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• 2014

Hsp90 is an ubiquitous molecular chaperone protein, which plays an important role in regulating maturation and stabilization of many oncogenic proteins. Due to its potential to simultaneously disable multiple signaling pathways, Hsp90 represents great promise as a therapeutic target of cancer. In this study, we synthesized flavokawain analogues and evaluated their biological activities against drug-resistant cancer cells. The study indicated that compound 1i impaired the growth of gefitinib-resistant non-small cell lung cancer (H1975), down-regulated the expression of Hsp90 client proteins including EGFR, Her2, Met, Akt and Cdk4, and upregulated the expression of Hsp70. The result strongly suggested that compound 1i inhibited the proliferation of cancer cells through Hsp90 inhibition. Overall, compound 1i could serve as a potential lead compound to overcome the drug resistance in cancer chemotherapy.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.116-122
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• 2002

Dehydrins (LEA Dll proteins) are one of the typical families of plant proteins that accumulate in response to dehydration, cold stress, abscisic acid, or during seed maturation. A 1.3-kb cDNA was cloned from a cDNA expression library of 5-day-old germinating maize scutellums under drought stress. The deduced protein sequence indicated a dehydrin gene encoding SK$_3$ LEA protein typically expressed during cold acclimation, but not by drought stress in barley and wheat. Thus, it was named maize DEHYDRIN2 (ZmDhn2). It accumulates rapidly and highly in drought-stressed scutellum and leaf tissues at any stage, but not under cold stress. ZmDhn2 gene was transformed into Arabidopsis thaliana for functional analysis under drought condition. From electrolyte leakage test, no significant difference showed between wild type and transformants under normal growth condition, but the leakage level of electrolyte in wild type plants was about 3 times as high as that in the transformed plants under drought stress. It suggests that ZmDHN2 playa role in increasing drought tolerance.

• International Journal of Knowledge Content Development & Technology
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• v.11 no.3
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• pp.45-62
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• 2021

Half a century has passed since the academic field of library and information science, which was born at the end of the 19th Century in the Western world, was introduced to Korea. Despite years of quantitative growth and qualitative maturation, the field has been facing the inconvenient truths of discrepancies in education levels arising from varying education providers, and weakened public confidence in librarian certification. Based on analysis of librarian training and education programs and the certification system, this research seeks to point out the limitations of the national librarian certification system, which is losing public confidence, and present a model for improvement. Library and information science education has expanded from universities to the academy of librarian education and lifelong education centers, and the librarian certification system has emerged as a target of reform. This research presents measures to improve the librarian certification system to government bodies and the Committee on Library and Information Policy with the purpose of providing grounds for policy enforcement.

• Sleep Medicine and Psychophysiology
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• v.27 no.2
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• pp.33-40
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• 2020

An infant's sleep varies considerably from that of adults in terms of structure, amount, and breathing pattern. After birth, sleep becomes evenly distributed throughout the day and night. Nighttime sleep gradually increases with the maturation of circadian rhythm, and sleep is gradually consolidated. Electroencephalography characteristics change with age, from early and dominant active (REM) sleep in newborns to increasing NREM sleep. Similar to other elements of growth, the upper respiratory tract and ribcage gradually increase in size with age, and respiratory control also improves. With these changes, sleep patterns also change. At this time that various sleep disorders may appear. Improved understanding of age-dependent changes in infant sleep can help determine the etiology and facilitate diagnosis of infant sleep diseases.

• Journal of English Language & Literature
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• v.55 no.3
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• pp.429-440
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• 2009

This paper does not follow the well-known critical practice of Charles Perke, Edward Brandabur and Phillip Herring who, regarding The Dead, James Joyce s earliest masterpiece, as the conclusion of Dubliners, classify Gabriel as one of the dead. Instead it concurs with such critics as William York Tindal, Kenneth Burke and Allen Tate who, interpreting The Dead as a story of Gabriel s spiritual maturation, discuss the famous snow vision at the end of the story as a signifier of his rebirth experience. A new reading of The Dead, which is the aim of this paper, examines the very processes which produce both form and content, thereby demonstrating that The Dead is a story of Gabriel s spiritual growth and that the supreme snow vision is prepared for his spirit which progresses towards a richer synthesis of life and death, a higher altitude of flight and wider horizons.