• The Plant Pathology Journal
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• v.19 no.3
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• pp.143-147
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• 2003

Sensitivity of Phytophthora infestans isolates to fungicides metalaxyl and ethaboxam in Korea was examined with 260 isolates for 3 years (9 isolates in 2000,93 isolates in 2001, and 158 isolates in 2002). Both Al and A2 mating types were found from the isolates collected for 3 years. Al mating type was dominant in the population with 8 isolates (88.9%) in 2000, 84 isolates (89.4%) in 2001, and 138 isolates (87.3%) in 2002. Only some isolates from diseased tomatoes in Buyergun and diseased potatoes in Pyeongchanggun were of the A2 mating type. As for metalaxyl sensitivity, 77.0% of the isolates were moderately resistant with 8 isolates (88.9%) in 2000, 73 isolates (77.7%) in 2001, and 120 isolates (75.9%) in 2002. Meanwhile, those found resistant were 1 isolate (11.1%) in 2000, 16 isolates (17.0%) in 2001, and 33 isolates (20.9%) in 2002. Only 5 isolates (3.2%) were sensitive to metalaxyl in 2002. There was no significant difference in the sensitivity among years. As for ethaboxam, no isolate was able to grow at 5.0 $\mu\textrm{g}$ /ml, and only four isolates (1.5 %) grew at 1.0 $\mu\textrm{g}$ /ml with heavy retardation compared with the untreated control. Based on these 3-year results, the minimum inhibitory concentration (MIC) of ethaboxam to p. infestans was determined to be 0.2-1.0 $\mu\textrm{g}$ /ml. Results indicate that resistance development by p. infestans to ethaboxam is not likely to occur in the natural condition. furthermore, there was no indication of cross resistance between metalaxyl and ethaboxam because all the isolates, regardless of classification for their sensitivity to metalaxyl, were not able to grow at 5.0 $\mu\textrm{g}$ /ml of ethaboxam.

• The Korean Journal of Malacology
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• v.8 no.1
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• pp.52-60
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• 1992

Clams were collected from mouth part of Mangeong Gang(river) of which heavy metals were heavily contaminated. Scapharca subcrenata, one of the clams, were fed to mice for 1-2 months with regular food stuffs. Eventhough difference of body weight was recognized between the experimental group and normal diat group, accumulation of heavy metals examined, cadmium was found 1.16 $\mu\textrm{g}$/gm in liver, 3.31 $\mu\textrm{g}$/gm in kidney and 0.21 $\mu\textrm{g}$/gm in blood of experimental group at 60th day, whereas 0.14 $\mu\textrm{g}$/gm, 0.35$\mu\textrm{g}$/gm and 0$\mu\textrm{g}$/gm respectively in normal diet group ate tje same period. No specific histo pathological finding was found in brain and kidney, although slighr fatty change and focal necrosis were found in liver tissues of the experimental group in second month.

• Korean Journal of Materials Research
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• v.9 no.10
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• pp.956-961
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• 1999

When the 0-2 mol% of $\textrm{La}_{3+}$ were added to the nanocrystalline $BaTiO_3$ powders and sintered at $1200~1400^{\circ}C$, the nanocrystailine $BaTiO_3$ ceramics having the average grain size of 110-240 nm were obtained except for when no $\textrm{La}_{3+}$ was added and sintered at > $1350^{\circ}C$. As the average grain size decreased from 240 nm to 110 nm, the tetragonality (c/a) and volume fraction of the $90^{\circ}$ domain decreased, and all the properties such as relative dielectric constant at room temperature, maximum relative dielectric constant at the temperature of phase transformation $\textrm{T}_{c}$ and diffuseness of phase transformation at $\textrm{T}_{c}$ also decreased. The results were attributed to the internal stress induced by inhibition of the $90^{\circ}$ domain formation in the case of finer grain size.

• Biomolecules & Therapeutics
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• v.9 no.3
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• pp.183-187
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• 2001

Nitric oxide (NO) produced in large amounts by the inducible nitric oxide synthase (iNOS) is known to be responsible for the vasodilation and hypotension observed in septic shock and inflammation. The inhibitors of iNOS, thus, may be useful candidate for the treatment of inflammatory diseases accompanied by the overproduction of NO. We prepared alcoholic extracts of Chinese medicinal plants and screened their inhibitory activity against NO production in lipopolysaccharide (LPS)-activated macrophages. Among the 80 kinds of extracts of herbal drugs, 15 extracts showed potent inhibitory activity of NO production above 80% at the concentration o$50\mu\textrm{g}/ml$. These potent extracts showed dose dependent inhibition of NO production of LPS-activated macrophages at the concentration of 50, 30,$10\mu\textrm{g}/ml$. Especially, Rhus chinensis, Senecio scandens and Wikstroemia indica showed most potent inhibition above 50% at the concentration of $10\mu\textrm{g}/ml$. These plants are promising candidates for the study of the activity-guided purification of active compounds and would be useful for the treatment of inflammatory diseases and endotoxemia accompanying the overproduction of NO.

• Restorative Dentistry and Endodontics
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• v.29 no.1
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• pp.36-43
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• 2004

The purpose of this study was to compare the microhardness and the fluoride content of enamel and dentin around fluoride- or non fluoride-containing restorations. Forty extracted human teeth were used and prepared cervical cavities on proximal surface. Experimental teeth were divided into five groups . Group 1 : Prime & Bond NT and Z100, Group 2 Prime & Bond NT and F2000, Group 3 : Scotchbond Multi-purpose and Z100, Group 4 : Scothcbond Multi-purpose and F2000, Group 5 : Fuji II LC. The cavities were filled with dentin adhesives and restorative materials. After each tooth was bisected, one half was tested microharaness and the other half was analyzed the fluoride at the enamel and dentin by an EPMA-WDX device. The results were as follows; 1. There was no statistical difference among the microhardness of enamel surface in all group. 2. The microhardness at dentin of $100{\;}\mu\textrm{m}$ point in Group 2 and $20{\;}\mu\textrm{m}$ point in Grocup 4 was lower than that of normal dentin (p>0.05). 3. There was no statistical difference among the fluoride content of enamel surface in all group. 4. The fluoride content at the dentin of $30{\;}\mu\textrm{m}$ point in Group 2 and 5 were higher than those at $100{\;}\mu\textrm{m}{\;}and{\;}200{\;}\mu\textrm{m}$ point in Group 2 and normal dentin (p<0.05). 5. At the dentin of $30{\;}\mu\textrm{m}$ point, Group 2 showed higher fluoride content than Group 1 and 3, and Group 5 showed higher fluoride content than other groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.822-829
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• 1999

Antimicrobial activity of dandelion(Taraxacum platycarpum D.) was investigated. Methanol extract of dried dandelion was fractionated to hexane, chloroform, ethylacetate, butanol and aqueous fraction. Ethylacetate fraction among these fractions showed the highest inhibitory effect on the microorganisms such as B. subtilis, L. monocytogenes, S. aureus, E. coli and V. parahaemolyticus at $500\mu\textrm{g}/disc$. Ethylacetate fraction was further fractionated into 13 fractions by silica gel column and thin layer chromatography(TLC). The results showed that ethylacetate fractions No. 4, 5 and 6 had high antimicrobial activity. These were mixed again, re separated and five fractions were obtained. Among them, No. 2 fraction had the highest inhibitory effect on the microorganisms, which was then separated into six fractions. In the 3rd fractionation, No. 3 fraction was identified as benzoic acid by HPLC, $^{1}H-NMR$ and GC MS.

• Environmental Mutagens and Carcinogens
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• v.21 no.1
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• pp.14-22
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• 2001

The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is of great concern at present. In this respect, administrative authorities has great concern to regulate and to evaluate the chemical hazard to environment and human health. The clastogenicity of 28 synthetic chemicals was evaluated in Chinese hamster lung fibroblast cells in vitro. Glycidylacrylate which is one of the most cytotoxic chemical among 28 chemicals tested revealed clastogenicity in the range of 0.31-1.25 $\mu\textrm{g}$/$m\ell$ both in the presence and absence of metabolic activation system. Neopentyl glycol (340-1360 $\mu\textrm{g}$/$m\ell$) also revealed weak positive result both in the presence and absence of metabolic activation system. Cyanoguanidine (/$420.5-841 $\mu\textrm{g}$m\ell$) and N-butylchloride ($231.5-926 $\mu\textrm{g}$/m\ell$) revealed weak positive result only in the absence of S-9 metabolic activation system. Nevertheless total aberration percentages of N-butylchloride in the presence of metabolic activation system, and 3,4＇-dichlorobenztrifluoride in the absence of S-9 metabolic activation revealed above 5% aberration, there is no statistical significance. From the results of chromosomal aberration assay with 28 synthetic chemicals in Chinese hamster lung cells, glycidylacrylate (CAS No. 106-90-0), neopentyl glycol (CAS No. 126-30-7), N-butyl chloride (CAS No. 109-69-3) and cyanoguanidine (CAS No. 461-58-5) revealed positive clastogenic results in this study.

• Korean Journal of Plant Tissue Culture
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• v.25 no.6
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• pp.515-518
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• 1998

The effect of ethylene on the proliferation of rhizomes and plant regeneration were investigated from rhizome segment culture of Cymbidium niveo-marginatum. Ethylene levels in the rhizome culture vessels were reached a maximum after 8 days of culture; total amount of ethylene evolution was much on the initiation of shoot induction than of rhizome proliferation. The treatment with ethephon on rhizomes was inhibited in the proliferation of rhizome and the growth of shoot length; however, the treatment was effective on shoot induction from rhizomes. Aminoethoxyvinylglycine(AVG) 1mg/L was effective on the proliferation of rhizomes and shoot induction from them; however, the proliferation of them was inhibited, and the growth of shoot length was significantly promoted at the concentration of 10mg/L AVG. The presence of $\textrm{AgNO}_{3}$ inhibited in the proliferation of rhizomes and shoot induction from them.

• Investigative Magnetic Resonance Imaging
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• v.6 no.1
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• pp.47-54
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• 2002

Purpose : Hippocampal atrophy is one of the characteristic pathologic findings of hippocampal sclerosis, for which MR imaging of the hippocampus is essential in the evaluation of hippocampal sclerosis. The purpose of this study is to present the normal MR volumetric data of the hippocampus in normal adult Korean and to compare those with MR volumetric data of hippocampus in patients with hippocampal s-clerosis, providing the diagnostic volume criteria of the hippocampal atrophy. Materials and methods : MR volumetry was performed in 30 normal adults and 28 patients with temporal lobe epilepsy whose final diagnosis was hippocampal sclerosis. The volumetric data were compared between sexes, right and left sides, and normal and abnormal hippocampus, and the volume criteria for the diagnosis of hippocampal atrophy was determined. Results : The mean $volumes({\pm}standard$ deviation) of normal Korean adult were $2.20{\pm}0.73\textrm{cm}^3$ (right) and $2.17{\pm}0.72\textrm{cm}^3$ (left) in male and $2.27{\pm}0.47{\;}\textrm{cm}^3$ (right) and $2.23{\pm}0.48\textrm{cm}^3$ (left) in female. The mean right-left differences were $0.14{\pm}0.11\textrm{cm}^3$ and $0.19{\pm}0.13\textrm{cm}^3$ in male and female, respectively. The MR volumetry showed no significant statistical differences between sexes and between right and left. The mean volume and standard deviation of the hippocampus in hippocampal sclerosis patients was $1.46{\pm}0.60{\;}\textrm{cm}^3$, and the right-left difference was $0.51{\pm}0.41\textrm{cm}^3$, In comparison of two volume distributions between normal adult group and hippocampal sclerosis patients group, the reasonable diagnostic volume criteria was $0.4{\;}\textrm{cm}^3$ as right-left volume difference, in which the sensitivity and specificity are 0.61 and 0.90. In all patients with right-left volume difference more than $0.4{\;}\textrm{cm}^3$, visual determination of unilateral hippocampal atrophy was possible. Conclusion : The MR-based hippocampal volumetry is a useful add-on of visual MR diagnosis, only when visual diagnosis of hippocampal sclerosis is difficult.

• Korean Journal of Animal Reproduction
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• v.13 no.3
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• pp.179-187
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• 1989

The experiment was carried out to study the profile of uterine specific protein during early pregnancy in sows and to test it's immunosuppressive activity. Uterine protein samples were obtained by flushing the uterine horn on Day 3, 6, 9, 12 and 15 of the estrous cycle and the pregnancy respectively and the protein concentration of each sample was determined. The change of uterine protein was examined by sodium dodecyl sulfate(SDS)-PAGE. The immunosuppressive activity of uterine secretory protein was investigated according to the lymphocyte blastogenesis response to mitogen. The results of this experiment are summarized as follows ; 1. The uterine protein during estrous cycle and early pregnancy was relatively constant up to Day 9, but increased on Day 12. Maxium total protein values were found on Day 15. The concentration of serum proteins were about 82-95 mg during estrous cycle, but decreased to about 70-82 mg during early pregnancy. 2. The proteins components similar electrophoretic patterns(PAGE) that were no differences (band ; a, b, c, d, e, f, g, I) on Days 3, 6 and 9 of the estrous cycle and pregnancy. But there were more 2 bands specifically on Day 12 of the pregnancy and on Day 15 of estrous cycle and showed more 4 bands on Day 15 of early pregnancy. They seemed to be acidoprotein and their average molecular weight were 38,000, 22,300 and 12,600. 3. When uterine protein were added 500$\mu\textrm{g}$/ml, there was no immunosuppresive activity on Day 3 of estrous cycle and lymphocyte blastogenesis was slightly suppressed on Day 3 of pregnancy. The immunosuppressive activity on Day 9 of estrous cycle and pregnancy appeared in 500$\mu\textrm{g}$/ml and 150$\mu\textrm{g}$/ml, respectively the uterine protein on Day 12 and 15 showed immunosuppresive activity, which at the level of 150$\mu\textrm{g}$/ml during non-pregnancy and at the level of 100 to 125$\mu\textrm{g}$/ml during early pregnancy, respectively.