• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.665-670
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• 2014

We isolated twelve lignans and three terpenoids were isolated from the n-hexane fraction of Schisandra chinensis extract. Using spectroscopic data and comparison with available literature, the following compounds were identified: (1) wuweizisu C, (2) gomisin N, (3) deoxyschisandrin, (4) gomisin A, (5) schisandrin, (6) chamigrenal, (7) schisanlactone D, (8) methylgomisin O, (9) angeloylgomisin O, (10) (-)-gomisin $L_2$, (11) schisandronic acid, (12) (-)-gomisin $L_1$, (13) (+)-gomisin $K_3$, (14) gomisin J, and (15) tigloylgomisin H. Notably, this was the first finding that compound (8) was isolated from this plant. Each compound was evaluated for its in vitro cytotoxic activities toward HL-60 (human leukemia), HeLa (human cervical carcinoma), and MCF-7 (breast cancer) cell lines. Compounds (7), (8), and (9) exhibited strong cytotoxic effects on HL-60 ($IC_{50}$ 7.37, 6.60, and $8.00{\mu}M$, respectively), whereas compound (6) exhibited weak cytotoxicity towards MCF-7 ($IC_{50}$ $30.50{\mu}M$). In addition, compound (8) showed the strongest activity towards HeLa cells ($IC_{50}$ $1.46{\mu}M$).

• Parasites, Hosts and Diseases
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• v.29 no.3
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• pp.311-313
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• 1991

This study revealed the infection status of p. larva with the metacercariae of M. orientalis in the Sunam stream of the Nakdong River, a well-known focus of Clonorchis sinensis. A total of 60 P larva were divided into :l groups by the size (80~90, 70~79, 60~69 and 50~59 mm) and were digested by pepsin-HCI solution in a $36^{\circ}C$ incubator. The metacercariae of M orientalis were collected and counted under a stereomicroscope. A total of 3,885 metacercariae were found, and average number/fish in each group were 143, 54, 23 and 40. They were $175.3{\times}155.4{\;}{\mu\textrm{m}}$ in average size and had thick cyst wall($13.1{\;}{\mu\textrm{m}}$ in average), By the results, it is proved that the life cycle of M. orientalis is actively maintained in the Sunam stream of the Nakdong River.

• YAKHAK HOEJI
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• v.42 no.4
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• pp.345-352
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• 1998

Praecoxin A, an ellagitannin, purified from Alnus hirsuta var.microphlla was evaluated on the antitumor activity. Praecoxin A had the significant cytotoxicity to s ix tumor cell lines: human chronic myelogenous leukemia K-562, human promyelocytic leukemia HL-60, mouse leukemia P388, mouse lymphocytic leukemia L-1210, sarcoma-l8O, mouse lymphoma L5178Y except L-1210. And the most sensitive cell line was K-562 ($ED_{50}=2.43{\mu}g/ml$). The $ED_{50} of praecoxin A against HL-60, P388, L-1210, sarcoma7l8O and L5178Y were 6.28, 8.66, 10.00, 7.01, $9.32{\mu}g/ml$, respectively. Praecoxin A showed the increasing effect in life span by 36.8% on the 1st day after treatment of 10mg/kg in mice bearing sarcoma-180 tumor cells (ascitic form) via NCI (National Cancer Institute, U.S.A.) protocol in vivo assay. As a result, praecoxin A is considered to show the antitumor activity.

• Journal of Environmental Health Sciences
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• v.23 no.3
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• pp.50-55
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• 1997

1992년부터 1995년까지 약 4개년 동안 전남 지역에서 사육하고 있는 가축의 유병률을 조사한 결과, 유방염으로 의심이 되는 젖소 970두 중에서 180두(18.6%)가 유방염에 이환되었으며, 돼지 2,400두 중에서 84두(3.5%)가 설사증에 이환되었고, 닭 1,010수중에서 9수(0.9%)가 설사증에 이환되었다. 대장균의 분리율을 조사한결과, 유방염에 이환되어 있는 젖소 180두중 37두(20.6%)에서 대장균이 분리되었으며, 설사증에 이환되어 있는 돼지 84두중 51두(60.7%)에서 대장균이 분리되었고, 설사증에 이환되어 있는 닭 9수중 5수(55.6%)에서 대장균이 분리되었다. Acriflavine을 이용하여 대장균의 S-R변이를 조사한 결과, S-R변이는 mercuric chloride, cysteine, caffeine, glucose, nicotine 등의 순으로 나타났는데, 이중 mercuric chloride가 가장 감수성이 높았다. 대장균의 항균요법제에 대한 감수성은 naxcel, linsmycin, cephalexin, gentamycin등이 높은 감수성을 나타내었는데, S-R변이 후에는 감수성이 일반적으로 저하되는 경향이었다.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.4
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• pp.273-278
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• 2015

The purpose of this study was to evaluate the in-vitro efficacy of PDT using red light emitting diode (LED) with Radachlorin for biofilm inhibition of clinical Candida albicans isolates. The suspensions containing C. albicans at $9{\times}10^8CFU/mL$ were prepared on yeast nitrogen base containing 5% glucose. The biofilm formation was grown for 3 h after seeding suspensions each 100 ul on a 96-well plate and then supernatant was discarded. Each well was treated with $0.39{\mu}g/mL$ from $50{\mu}g/mL$ concentrations of Radachlorin on adherent biofilm. After a 30-minute incubation, light was irradiated for 30, 60, or 90 minutes using the following light source of wavelength 630 nm LED, at energy densities of 14, 29, and $43J/cm^2$. Afterwards, all supernatant was removed and dried. Adherent cells were stained with safranin O and dried. The cell viability was measured using a microplate reader at 490 nm. Also, a fluorescent signal on C. albicans was observed by saturation of a photosensitizer. In conclusion, a significant inhibition of 72.5% was observed to C. albicans on biofilm at the Radachlorin dose of $50{\mu}g/mL$ with 630 nm LED. The Photosensitizer (Radachlorin) was adequate at 30 minuttes for C. albicans. Overall, the results showed that inhibition of biofilm formation was Radachlorine dose-dependent. The results suggest that PDT, using Radachlorin with 630 nm LED, is able to decrease biofilm formation of C. albicans.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.168-173
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• 2000

Anticariogenic activity of the unripe apple extract was studied by observing the inhibitory effects on GTase(glucosyltransferase) activity, cell adherence and acid production of Streptococcus mutans. Among the four S. mutans strains, S. mutans MT 8148 had the highest water-insoluble glucan forming activity. (+)-Catechin and tannic acid, the major components of the unripe apple polyphenols inhibited GTase activity by 60% at 1 mg/ml and 90% at 5 mg/ml. Tannic acid and unripe apple extract inhibited adherence ability of S. mutans by 50% and 30%, respectively. But the acid production of S. mutans was not influenced by the polyphenols. Disc diffusion test showed that the polyphenols have no antimicrobial activity against S. mutans, which indicates that the inhibition of GTase activity and cell adherence were not resulted from the cell growth inhibition. Our results convinced the possible application of the unripe apple extract as the anticariogenic food additives.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.191-200
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• 2022

This study analyzes the perception survey of the general public on the problems of a neologism(new words), which are frequently used in media media, and derives improvement measures and implications based on the data. In general, it can be seen that the creed is exposed and used indiscriminately through media, and those in their 20s and 30s are positive for the use of new words and those in their 50s and 60s are relatively negative. The biggest problem is that excessive use of creed can cause conflict and alienation between generations, and the need for correct Korean use is recognized overall as it can enhance Hangeul destruction and inappropriate social awareness. However, media outlets often use new words in a positive way to induce interest and enrich content by using them in the right place for the latest trends, such as small but certain happiness. As an alternative to this problem, self-purification of media workers is the most important, and it is recommended to encourage proper use of Korean through media literacy education and campaigns.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.77-81
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• 2012

We assessed the toxicity of cryoprotectant agents (CPAs) to gametophytic thalli of red alga Porphyra yezoensis at room temperature. The CPAs used were: dimethyl sulfoxide (DMSO), ethylene glycol (EG), glycerol (GC), 1,2-butanediol (1,2-BD), 1,3-butanediol (1,3-BD), 2,3-butanediol (2,3-BD), 1,3-propanediol (1,3-PD) and propylene glycol (PG). CPA concentrations of 10, 15, 20, 25, 30, 35, 40, 45, and 50% were employed with 30 or 60 s immersion. The toxicity of the eight CPAs to gametophytic thalli of P. yezoensis was in the order: 1,3-BD < DMSO ${\approx}$ 2,3-BD ${\approx}$ PG ${\approx}$ EG < GC < 1,3-PD ${\approx}$ 1,2-BD. All thalli were more sensitive to high CPA concentrations, and most (>75%) thalli survived exposure to 10-25% CPA for 60 s. These data will facilitate selection of the optimal cryoprotectant concentration for cryopreservation of P. yezoensis thalli.

• Journal of the Korean Society of Clothing and Textiles
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• v.38 no.3
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• pp.404-414
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• 2014

This study investigates the dyeability and fastness of jacquard fabric for blind using low-melting flame retardant polyester. Two types of jacquard fabric were prepared with a low-melting flame retardant polyester and regular polyester. The low-melting flame retardant polyester has a sheath and a core. The core consists of flame retardant polyester and the sheath consists of low-melting polyester. Disperse red 50 (DR 50), disperse blue 56 (DB 56), disperse yellow (DY 54) of E-type dyes and disperse 92 (DR 92), disperse blue 60 (DB 60), disperse yellow (DY 79) of S-type dyes were used and dyed on jacquard fabrics dependent of dyeing temperature and time. The fastness, dye exhaustion, color strength (K/S value), and colorimetric properties of jacquard fabrics were evaluated. The dyeability of S-type dyes were higher than E-type dyes. The experiments indicated optimum dyeability that the dyeing temperature was $110^{\circ}C$ for E-type dyes and $120^{\circ}C$ for S-type dyes for 40 minutes. The fastness to washing and light were excellent at a 4-5 grade.

• Phonetics and Speech Sciences
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• v.10 no.4
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• pp.67-76
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• 2018

This study was performed to investigate acoustic characteristics of sustained vowels produced by Seoul Korean speakers. For this study, three hundred nine healthy adults were chosen as participants from Korean Standard Speech Database. These subjects were divided into five chronological age groups (20s, 30s, 40s, 50s, 60-70s) and two gender groups (male and female). Fundamental frequency (f0), jitter, shimmer, and NHR (noise-to-harmonics ratio) was measured with 8 Korean vowels (/ɑ/, /æ/, /ʌ/, /e/, /o/, /u/, /ɯ/, /i/) by using Praat. The results showed that the vowel type significantly affected all acoustic parameters. Gender affected f0, jitter, and NHR significantly. The mean female speakers' f0 was greater than the males', and the mean jitter and NHR of male speakers was greater than the females'. Moreover, age affected shimmer and NHR significantly; in particular, the shimmer and NHR of elderly speakers was greater than the young speakers.