• Phonetics and Speech Sciences
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• v.1 no.3
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• pp.19-28
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• 2009

This paper reports experimental findings about the duration feature of the acoustic components of English stops in Korean speakers' voicing perception. In our experiment, 35 participants discriminated between recorded stimuli and digitally transformed stimuli with different duration features from the original stimuli. 72 sets of paired stimuli are generated to test the effects of the duration feature in various phonetic contexts. The result of our experiment is a complicated cross-tabulation with 540 cells defined by five categorical independent variables plus one response variable. To find a meaningful generalization out of this complex frequency table, we ran logit log-linear regression analyses. Surprisingly, we have found that there is no single effect of the duration feature in all phonetic contexts on Korean speakers' perception of the voicing contrasts of English stops. Instead, the logit log-linear analyses reveal that there are interaction effects among phonetic contexts (=C), the places of articulation of stops (=P), and the voicing contrast (=V), and among duration (=T), phonetic contexts, and the places of articulation. To put it in mathematical terms, the distribution of the data can be explained by a simple log-linear equation, logF=${\mu}+{\lambda}CPV+{\lambda}TCP$.

• Macromolecular Research
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• v.17 no.1
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• pp.19-25
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• 2009

In order to enhance the gene delivery efficiency and decrease the cytotoxicity of polyplexes, we synthesized Solutol-g-PEI by conjugating polyethyleneimine (PEI) to Solutol (polyoxyethylene (10) stearate), and evaluated its efficiency as a possible nonviral gene carrier candidate. Structural analysis of synthesized polymer was performed by using $^1H$-NMR. Gel retardation assay, particle sizes and zeta potential measurement confirmed that the new gene carrier formed a compact complex with plasmid DNA. The complexes were smaller than 150 nm, which implicated its potential for intracellular delivery. It showed lower cytotoxicity in three different cell lines (Hela, MCF-7, and HepG2) than PEI 25 kDa. pGL3-lus was used as a reporter gene, and the transfection efficiency was in vitro measured in Hela cells. Solutol-g-PEI showed much higher transfection efficiency than unmodified PEI 25 kDa.

• Archives of Pharmacal Research
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• v.6 no.2
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• pp.141-142
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• 1983

To find anititumor metabolites in Korean basidiomycetes, the shake-cultured mycelia of eight of the higher fungi were extracted with hot water and the extracts, after being partially purified, were subjected to in vivo antitumor test. When administered i. p. at the dose of 30mg/kg/day for ten consecutive days into the female ICR mice, which had been implanted with $1{\times}10^{6}$ / cells of sarcoma 180 twenty four hours before the first injection, the extracts of Agaricus campestris, Lyophyllum decastes, Lyophyllum ulmarium, Armillaria Tabescence and Calvatia exipuliformis respectively showed inhibition ratios of 64.1%, 65.45, 60.-%, 53.0 and 49.3%. These five species were selected for further study, whereas the extracts of Phallus impudicus, Coprinus comatus and Pholiota squarrosa whih showed the inhibition ratios of 31.2%, 33.5% and 19.0% were discontinued.

• Korean Journal of Veterinary Research
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• v.26 no.2
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• pp.265-276
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• 1986

The bovine serum factor influencing the growth of swine testicle (ST) cell and the END effect of hog cholera SN test was studied. Throughout the experimental studies. following results were obtained and summarized. 1. Bovine whole serum of 16(76.2%) and 4(19.0%) samples out of 21 have shown a positive ST cell growth and the END effect, respectively. However, all of 21(100%) and 8(38.1%) samples out of 21 serum supernatant fractions, prepared from the bovine whole serum, have shown positive ST cell growth and END effect, respectively. 2. In the SDS-polyacrylamide gel electrophoretic analysis of the bovine whole serum and the supernatant fractions, ST cell growth inhibiting factor was proved present in globulin fraction and in whole gel plate as a diffusible component. 3. The END ineffective component present in the whole serum and its supernatant fraction was proved to be BVDV neutralizing antibody. 4. The difference of osmolarity, optical density, pH, degree of precipitant formation following heat cold treatment, A/G ratio as we11 as electrophoretic pattern and NDV SN index of the samples were not correlated to the degree of 57 cell growth and to the END effectiveness.

• Journal of Microbiology and Biotechnology
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• v.19 no.6
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• pp.622-628
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• 2009

In the present study, the therapeutic potential of purified and well-characterized bacteriophages was evaluated in thermally injured mice infected with Klebsiella pneumoniae B5055. The efficacy of five Klebsiella phages (Kpn5, Kpn12, Kpn13, Kpn17, and Kpn22) was evaluated on the basis of survival rate, decrease in bacterial counts in different organs of phage-treated animals, and regeneration of skin cells as observed by histopathological examination of phage-treated skin. Toxicity studies performed with all the phages showed them to be non-toxic, as no signs of morbidity and mortality were observed in phage-treated mice. The results of the study indicate that a single dose of phages, intraperitoneally (i.p.) at an MOI of 1.0, resulted in significant decrease in mortality, and this dose was found to be sufficient to completely cure K. pneumoniae infection in the burn wound model. Maximum decrease in bacterial counts in different organs was observed at 72 h post infection. Histopathological examination of skin of phage-treated mice showed complete recovery of burn infection. Kpn5 phage was found to be highly effective among all the phages and equally effective when compared with a cocktail of all the phages. From these results, it can be concluded that phage therapy may have the potential to be used as stand-alone therapy for K. pneumoniae induced burn wound infection, especially in situations where multiple antibiotic-resistant organisms are encountered.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.366-370
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• 1992

Salient chromosomal variations during the first meiotic division in primary spermatocyLes of the three brown planthopper, Nilaparvata lugens (Stal) , biotypes were observed. The meiotic index was highest in biotype 3 (58.6), followed by biotype 1 (39.4) and biotype 2 (23.6). Total chromosomal aberration including agmatoploidy, aneuploidy, loose pairings of sex chromosomes, and cytoplasmic shrinkage was found high in the order of biotype 1 (60.6%),2 (47.9 %), and 3 (38.1 %). However, percent agmatoploidy was highest in biotype 2 (19.6%) whereas in biotypes 3 and 1, it was 9.5% and 2.5%, respectively. The number of cells with isolated sex chrosomomes was observed highest in biotype 2.

• Journal of Korean Biological Nursing Science
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• v.12 no.3
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• pp.127-132
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• 2010

Purpose: The aim of this study is to evaluate the effect of Xanthium sibiricum Patr. on carcinogenesis. Method: Water extract from Xanthium sibiricum Patr. (XPW) was prepared and investigated for the potential antitumor activity and inhibition of benzo[a]pyrene-DNA adduct formation and free radical formation. Result: It was shown that the water possess considerable toxicity toward tumor cell lines. Concentration of XPW at 1.0 mg/mL and 2.5 mg/mL resulted in more than 30% inhibition of growth in HeLa cells. Toxicity of XPW to A549 revealed that 54% inhibition of growth at concentration of 2.5 mg/mL. At concentrations of 0.5 mg/mL, 1.0 mg/mL and 2.5 mg/mL of XPW, the binding of [$^3H$]B[a]P metabolites to DNA of human Chang cell was inhibited by 19%, 33%, and 41%, respectively. There 18% and 32% inhibition in the free radical formation with XPW at the concentration of 1.0 mg/mL and 2.5 mg/mL, respectively. Conclusion: Water extract from Xanthium sibiricum Patr. (XPW) has antitumor and cancer chemopreventive activities.

• Korean Journal of Animal Reproduction
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• v.20 no.3
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• pp.315-322
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• 1996

The study was conducted to determine the optimal glucose, superoxide dimutase(SOD) and catalase levels during the in vitro culture of porcine oocytes matured and fertilized in vitro for morulae and blastocyst development. Oocytes were cultured for 0~8 days in TCM-199 medium supplemented with 20% FCS, different glucose, SOD and catalase levels. The results are summairzed as follows ; 1. The in vitro developmental rates of porcine oocytes cultured in TCM-199 medium containing 0.1, 0.3, 0.5, 1.0, 3.0 mM glucose levels 0~3 and 0~8 days after insemination were 22.8, 24.2, 21.9, 20.0, 12.1 and 21.9, 26.7, 25.0, 22.6, 16.7%, respectively. 2. The in vitro developmental rates of porcine oocytes cultured in TCM-199 medium containing 100, 200, 300, 500 $\mu\textrm{g}$/ml SOD levels 0~3 and 0~8 days after insemination were 16.7~23.3 and 16.7~25.0%, respectively. High levels of SOD(500 $\mu\textrm{g}$/ml) significantly reduced the rates of molurae and blastocysts stage(P<0.05). 3. The in vitro developmental rates porcine oocytes cultured in TCM-199 medium containing 100, 200, 300, 500 $\mu\textrm{g}$/ml catalase levels 0~3 and 0~8 days after insemination were 18.8~26.7 and 19.4~28.1%, respectively, and there was significant differences on the development to the molurae and blastocysts stage among the cumulus cells and glucose levels.

• Journal of Preventive Medicine and Public Health
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• v.19 no.2 s.20
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• pp.177-183
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• 1986

Subjective symptoms, counts of blood cells and liver function test were conducted on 198 male workers who were exposed to toluene in Kyungin area from September to November, 1986. According to the level of urinary hippuric acid concentration, the total sample was classified into the high exposure group ($concentration{\geqq}3g/1$) and the low exposure group(concentration<3g/1). The following findings were obtained by comparing the two group: 1) Contrary to the previous findings. the urinary hippuric acid concentration of toluene exposed workers showed bimodal distribution. It meant that the toluene exposed workers were mixed with the non-exposed or minimal exposed workers. 2) The high exposure group showed a lower level of leucocytes counts ($6,630{\pm}1,860{\mu}l$) than the low exposure group ($6,340{\pm}1,960/{\mu}l$). 3) The high exposure group showed a higher level of SGOT, SGPT and r-GTP than the low exposure group (p<0.05). 4) The high exposure group complained much more subjective symptoms (e. g. skin rash, loss of appetite, palpitation) than the low exposure group.

• Journal of Korean Neurosurgical Society
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• v.39 no.6
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• pp.432-437
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• 2006

Objective : In order to establish the index of degeneration, the authors performed a histochemical study with Safranin-O staining and investigated the occurrence of apoptosis in the human intervertebral disc. Methods : Eighteen intervertebral disc specimens surgically extracted from the patients and two additional specimens from the autopsied cases were stained with Safranin-O for proteoglycan according to a standard protocol. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate- biotin nick end labeling[TUNEL] was used to detect the fragmented DNA known to be associated with apoptotic cell death and classification scheme was formulated for categorization of the degree of Safranin-O staining [normal, moderate reduction, faint] by modification of Makin's histological-histochemical grading. The Kruskal-Wallis H test and Chi-square test were used for statistical analysis. Results : The statistical results showed a significant difference in the mean age between "normal" Safranin-O staining group and the others [19.3 versus 55, 43.4, p=0021]. However, there was no statistically significant correlation between Safranin-O staining and MR grading of disc degeneration. Only six of eighteen surgical specimens and none in autopsies showed positive apoptotic cells in TUNEL staining. Conclusion : The determination of the degree of degeneration in surgically obtained disc tissue per se by histochemical staining or by the degree of apoptosis that corresponds to its morphologic change was not feasible.