• Journal of Distribution Science
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• v.14 no.4
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• pp.47-53
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• 2016

Purpose - The objective of this study is to investigate the dynamic relationships among Advertising Cost (AD), Newly Registered Users(NRU), and Buying Users(BU) of Social Network Game(SNG). SNG is getting pervasive mainly due to the rapid growth of mobile game and Social Network Service(SNS). It would be helpful for marketing researchers interested in SNG and related practitioners to understand the changes in AD, NRU, and BU with time as well as the effects on one another in mutual and dynamic way. Research Design, Data, and Methodology - Necessary data were collected from Social Network Game(SNG) company. AD, NRU, and BU are endogenous variables, but new event such as launching (event) and holidays(holiday) are exogenous dummy variables. Vector Auto regression (VAR) model is generally used to examine and capture the dynamic relationships among endogenous variables. VAR model can easily capture dynamic and endogenous relationships among time-series variables. Vector Auto regression with Exogenous variables(VARX) is a model in which exogenous variables are added to VAR. To investigate this study, VARX is applied. Result - By estimating the VARX model, the author finds that the past periods' NRU affect negatively and significantly the present AD, and past periods' BU have a positive and significant impact on the increase of AD. In addition, the author shows that the past periods' AD and BU have a positive and significant effect on the increase of NRU, and the past periods' AD affect positively and significantly BU. While the impact of AD on NRU happens after 3 or 4 days (carryover effect), that of AD on BU comes about within just 1 or 2 days (immediate effect). The effect of BU on NRU can be considered as word of mouth (WOM effect). Therefore, SNG companies can obtain not only the growth of revenue but also the increase of NRU by increasing BU. Through those results, the author can also find that there are significant interactions between endogenous variables. Conclusion - This study intends to investigate endogenous and dynamic relationships between AD, NRU, and BU. They also give managerial implications to practitioners for SNS and SNG firms. Through this study, it is found that there exist significant interactions and dynamic relationships between those three endogenous variables. The results of this study can have meaningful implications for practitioners and researchers of SNG. This research is unique in that it deals with "actual" field data and intend to find "actual" relationships among variables unlike other related existing studies which intend to investigate psychological factors affecting the intention of game usage and the intention of purchasing game items. This study is also meaningful by showing that the increase of BU can be a good strategy for "killing birds with one stone" (i.e., revenue growth and NRU increase). Although there are some limitations related with future research topics, this research contributes to the current research on SNG marketing in the above mentioned ways.

• Journal of Ginseng Research
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• v.17 no.3
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• pp.232-235
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• 1993

We investigated the effect of antioxidants (ascorbate, glutathione, and sodium azide), which efEectively inhibited the chlorophyll bleaching of Panax ginseng CA Meyer under the high light intensity, treated by folilar wiping on the early stage of photosynthesis and transpiration of ginseng in the 5000 $\mu$mol photon.$m^{-2}$.$s^{-1}$. Ascorbate and glutathione, endogenous antioxidant, completely recovered ginseng from the photoinhibition, but sodium azide, synthetic quencher, showed negative effect. We assumed that endogenous antioxidants could be available to the protection of the leaf-burning phenomenon of ginseng.

• The Journal of Internal Korean Medicine
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• v.12 no.1
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• pp.98-104
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• 1991

I studied some important medical Literatures in order to examine the cause of Hoarse Voice and found out some facts of follows ; 1. The exogenous cause of disease in wind. 2. Wind-cold, Wind-fire, Wind-heat, Summer-heat, Heat. 3. The endogenous cause of disease is deficiency of Yin and dificiency of blood leads fire-evil was lung-dry stool dificiency of body fluid. 4. The non-exo-endogenous causes of disease is sing ballads and call out.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.2
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• pp.71-76
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• 1998

To define the relations between endogenous GA levels and growth and flowering in short-day plant sorghum, growth retardant BX-112 was applied to two sorghum genotypes, wild-type and phytochrome B mutant (phyB-1), which grows faster and flowers earlier than the wild-type. BX-112 and $GA_3$ were applied as a soil drench, and plant height, culm length, and date to floral initiation were investigated. Endogenous GAs contents were measured with GC-MS-SIM. BX-112 treatments inhibited shoot growth in both genotypes and drastically reduced $GA_1$ and $GA_8$ levels. With increasing BX-112 concentrations, $GA_1$ concentrations declined linearly, but caused the accumulation of intermediates from $GA_12$ to $GA_20$. This result implies that $GA_1$ is the major active endogenous GA in shoot elongation in a short day plant sorghum. The inhibition of plant growth in both of wild type and phyB-1 by BX-112 was very similar, while BX-112 effects on floral initiation in two types of plants differed significantly. Floral initiation of phyB-1 was not affected by BX-1l2, but that of wild-type was delayed as BX-1l2 concentration increased. Because BX-112 treatment causes accumulation of biosynthetic intermediates between synthetic pathway from $GA_12$ to $GA_20$ and because phyB-1 is altered in GA metabolism in this same region of the early C13-hydroxylation pathway, BX-112 may fail to block flowering of phyB-1.

• Biomedical Science Letters
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• v.11 no.4
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• pp.487-492
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• 2005

The baculovirus/insect cell expression system is of great value in the study of structure-function relationships in mammalian glucose-transport proteins by site-directed mutagenesis and for the large-scale production of these proteins for mechanistic and biochemical studies. Spodoptera frugiperda Clone 21 (Sf2l) cells grow well on TC-100 medium that contains $0.1\%$ D-glucose as the major carbon source, strongly suggesting the presence of endogenous glucose transporters. However, very little is known about the properties of the endogenous sugar transporter(s) in Sf2l cells, although a saturable transport system for hexose uptake has been previously revealed in the Sf cells. In order to further examine the substrate and inhibitor recognition properties of the Sf2l cell transporter, the ability of hexoses to inhibit 2-deoxy-D-glucose (2dGlc) transport was investigated by measuring inhibition constants $(K_i)$. The $K_i's$ for reversible inhibitors were determined from plots of uptake versus inhibitor concentration. Transport was effectively inhibited by D-mannose and D-glucose. Of the hexoses tested, L-glucose had the least effect on 2dGlc transport in the Sf2l cells, indicating that the transport is stereoselective. Unlike the human HepG2 type glucose transport system, D-mannose had a somewhat greater affinity for the Sf2l cell transporter than D-glucose, implying that the hydroxyl group at the C-2 position is not necessary for strong binding. However, epimerization at the C-4 position of D-glucose (D-galactose) resulted in a dramatic decrease in affinity of the hexose for the Sf2l cell transporter. Such a lowering of affinity might be the result of the involvement of the C-4 hydroxyl in hydrogen bonding. It is therefore suggested that Sf2l cells were found to contain an endogenous sugar transport activity that in several aspects resembles the human HepG2 type glucose transporter, although the insect and human transporters do differ in their affinity for cytochalasin B.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.255-260
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• 2008

The purpose of this study was to evaluate the bioequivalence of the test (Daewoo Hydrocortisone 10 mg, Daewoo Pharm. Co., Busan, Korea) and reference (Jenapharm Hydrocortisone 10 mg, JayTech Biogen, Seoul, Korea) hydrocortisone tablets. Twenty-four healthy male Korean volunteers were divided into two groups with a randomized $2{\times}2$ cross-over design. In order to suppress the endogenous cortisol secretion, a single oral dose of Dexamethasone (4 mg) was administered 10 hr prior to hydrocortisone administration. Blood samples were withdrawn for 10 hr at the predetermined intervals after a single oral dose of hydrocortisone (20 mg). The serum concentration of hydrocortisone was analyzed by HPLC/UV using a column switching method after liquid-liquid extraction process. The pharmacokinetic parameters ($AUC_{0{\sim}10hr}$, $C_{max}$, and $T_{max}$) of the test and reference hydrocortisone tablets were determined while the secretion of endogenous cortisol was being suppressed. The pharmacokinetic parameters of the test tablet were not statistically different from those of the reference tablet at ex value was 0.05. The 90% confidence intervals for the average ratio (test/reference) of $AUC_{0{\sim}10hr}$ and $C_{max}$ were within the Korea Food and Drug Administration acceptance range of 0.80-1.25 ($0.89{\sim}0.99$ and $0.86{\sim}0.99$ for $AUC_{0{\sim}10hr}$ and $C_{max}$, respectively). Therefore it was concluded that the test tablet, Daewoo Hydrocortisone tablet was bioequivalent to the reference tablet, Jenapharm Hydrocortisone tablet.

• BMB Reports
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• v.53 no.10
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• pp.521-526
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• 2020

Endogenous retroviruses (ERVs) are retrotransposons present in various metazoan genomes and have been implicated in metazoan evolution as well as in nematodes and humans. The long terminal repeat (LTR) retrotransposons contain several regulatory sequences including promoters and enhancers that regulate endogenous gene expression and thereby control organismal development and response to environmental change. ERVs including the LTR retrotransposons constitute 8% of the human genome and less than 0.6% of the Caenorhabditis elegans (C. elegans) genome, a nematode genetic model system. To investigate the evolutionarily conserved mechanism behind the transcriptional activity of retrotransposons, we generated a transgenic worm model driving green fluorescent protein (GFP) expression using Human endogenous retroviruses (HERV)-K LTR as a promoter. The promoter activity of HERV-K LTR was robust and fluorescence was observed in various tissues throughout the developmental process. Interestingly, persistent GFP expression was specifically detected in the adult vulva muscle. Using deletion constructs, we found that the region from positions 675 to 868 containing the TATA box was necessary for promoter activity driving gene expression in the vulva. Interestingly, we found that the promoter activity of the LTR was dependent on che-1 transcription factor, a sensory neuron driver, and lin-15b, a negative regulator of RNAi and germline gene expression. These results suggest evolutionary conservation of the LTR retrotransposon activity in transcriptional regulation as well as the possibility of che-1 function in non-neuronal tissues.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2493-2496
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• 2010

Erythropoietin (EPO) is mainly produced in kidney and stimulates erythropoiesis. The use of recombinant EPOs for doping is prohibited because of its performance enhancing effect. This study investigated whether biosimilar EPOs could be differentiated from endogenous one by iso-electro-focusing plus double blotting and SDS-PAGE for antidoping analysis. The established method was validated with positive control urine. The band patterns were reproducible and meet the criteria, which was made by world anti doping agency (WADA). Isoelectric focusing was conducted in pH range 2 to 6. Recormon (La Roche), Aropotin (Kunwha), Epokine (CJ Pharm Co.), Eporon (Dong-A), Espogen (LG Life Sciences), and Dynepo (Shire Pharmaceuticals) were detected in basic region. All biosimilars showed discriminative isoelectric profiles from endogenous EPO profiles, but they showed different band patterns with the reference one except Epokine (CJ Pharm Co.). Next, SDS-PAGE of biosimilar EPOs resulted in different molecular weight patterns which were distributed higher than endogenous EPO. Commercial immune assay kit as an immune affinity purification tool and immobilized antibody coated magnetic bead were tested for the purification and concentration of EPO from urinary matrix. The antibody-coated magnetic bead gave better purification yield. The IEF plus double blotting and SDS-PAGE with immunoaffinity purification method established can be used to discriminate biosimilar EPOs from endogenous EPO.

• Korean Journal of Plant Tissue Culture
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• v.22 no.6
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• pp.351-355
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• 1995

A truncated Polygalacturonase (PG) cDNA was fused in reverse orientation to the CaMV 35S promoter of the binary vector pCA643, and introduced into tomato cells by Agrobaderium - mediated transformation. Transformed cells were selected using kanamycin as select agent then regenerated into plants. After selfed, one transgenic line (T9), was germinated and grown on MS medium containing 1 mg/mL of kanamycin Genomic Southern analysis of a T9 progeny with labelled PG2 cDNA probe showed a single antisense PC fragment as well as the endogenous PG2 gene, suggesting that PC antisense gene was integrated into tomato genome. Northern blot analysis demonstrated that the antisense RNA was produced from the transgene at much tiger level than the endogenous PG2 gene. Polygalacturonase activity analysis of the fruit from transgenic plants demonstrated that the antisense transgene expression caused 4 to 60% reduction of endogenous PG activity.

• Mass Spectrometry Letters
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• v.7 no.4
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• pp.111-115
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• 2016

Glycerol was identified and isolated from endogenous interferences during analysis of human urine using high-resolution mass spectrometry (HRMS) for doping control. Urinary sample preparation was simple; the samples were diluted with an organic solvent and then analyzed using a liquid chromatography-mass spectrometry ("dilute and shoot" method). Although the interfering ion peaks were observed at the similar retention time of glycerol, the inference could be identified by isolation with HRMS and further investigation. Thus, creatinine was identified as the endogenous interference for glycerol analysis and it also caused ion suppression resulting in the decrease of glycerol signal. This study reports the first identification and efficient isolation of endogenous interferences in human urine for "dilute and shoot" method. The information about ion suppression could be novel to prevent overestimation or a false result for antidoping analysis.