• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.50-54
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• 2001

Effect of NO$_3$:NH$_4$ratio and pH of nutrient solution on nitrate content of leaves was investigated for leaf lettuce(Lactuca sativa L.) grown by a deep flow technique. Ratios(in me.L$^{-1}$ ) of NO$_3$:NH$_4$tested were 12:1, 10:3 and 8:5. The treatment of 8:5 NO$_3$:NH$_4$ratio had two solutions, one with uncontrolled pH and the other with automatically controlled pH. Solution pH continuously increased in 12:1 NO$_3$:NH$_4$treatment. Solution pH decreased gradually more as NH$_4$ratio increased. Treatment of 8:5 NO$_3$:NH$_4$with automatic pH control satisfactorily maintained the solution pH in the range of pH 5.5-6.0. Nitrate content in leaves was the greatest in treatment of 12:1 NO$_3$:NH$_4$ and the least in treatment of 8:5 NO$_3$:NH$_4$with automatic pH control. Fresh weight decreased in treatments of 10:3 and 8:5 NO$_3$:NH$_4$, whereas it increased in treatments of 12:1 and 8:5 NO$_3$:NH$_4$with pH control. It was concluded that the growth and leaf nitrate content were the greatest in high NH$_4$treatment with automatic pH control.

• Molecules and Cells
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• v.24 no.2
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• pp.194-199
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• 2007

GCN4 is a typical eukaryotic transcriptional activator that is implicated in the expression of many genes involved in amino acids and purine biosyntheses under stress conditions. It is degraded by 26S proteasomes following ubiquitination. However, the immediate receptor for ubiquitinated Gcn4p has not yet been identified. We investigated whether ubiquitinated Gcn4p binds directly to Rpn10p as the ubiquitinated substrate receptor of the 26S proteasome. We found that the level of Gcn4p increased in cells deleted for Rpn10p but not in cells deleted for RAD23 and DSK2, the other ubiquitinated substrate receptors and, unlike Rpn10p, neither of these proteins recognized ubiquitinated Gcn4p. These results suggest that Rpn10p is the receptor that binds the polyubiquitin chain during ubiquitin-dependent proteolysis of Gcn4p.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.82-89
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• 1986

This study was designed to observe the effects of dietary P/S ratio on lipid component in plasma and tissues. Changes in plasma total cholesterol and triglyceride concentration and also cholesterol and triglyceride concentrations in liver, small intestine and aorta were determined in adult rats fed experimental diets providing different dietary P/S ratios as 0.05, 0.5, 1.0, 2.0, 3.0, and 4.0, respectively. The results obtained were summarized as follows; 1. Feed efficiency ratio was not significantly different among six groups at 2nd week. But at 4th week, the higher the dietary P/S ratio the higher the feed efficiency ratio. 2. Plasma cholesterol level was getting higher as increased dietary P/S ratio at 2nd week, But that was significantly decreased as P/S ratio increased at 4th week. 3. Plasma triglyceride level was significantly decreased as increased dietary P/S ratio at 4th week. 4. Cholesterol concentrations in liver and small intestines were getting higher as increased dietary P/S ratio at 4th week, But aortas cholesterol concentration was not influenced by P/S ratio. 5. Triglyceride concentrations in liver and small intestines were significantly increased as increased dietary P/S ratio. On the contrary, triglyceride concentration in aortas was not influenced by P/S ratio.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2083-2087
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• 2014

Colorectal cancers remain to be a common cause of cancer-related death. Early-onset cases as well as those of various ethnic origins have aggressive clinical features, the basis of which requires further exploration. The aim of this work was to examine the expression patterns of $p15^{INK4b}$ and SMAD4 in colorectal carcinoma of different ethnic origins. Fifty-five sporadic colorectal carcinoma of Egyptian origin, 25 of which were early onset, and 54 cancers of Finnish origin were immunohistochemically stained with antibodies against $p15^{INK4b}$ and SMAD4 proteins. Data were compared to the methylation status of the $p15^{INK4b}$ gene promotor. $p15^{INK4b}$ was totally lost or deficient (lost in ${\geq}50%$ of tumor cell) in 47/55 (85%) tumors of Egyptian origin as compared to 6/50 (12%) tumors of Finnish origin (p=7e-15). In the Egyptian cases with $p15^{INK4b}$ loss and available $p15^{INK4b}$ promotor methylation status, 89% of cases which lost $p15^{INK4b}$ expression were associated with $p15^{INK4b}$ gene promotor hypermethylation. SMAD4 was lost or deficient in 25/54 (46%) tumors of Egyptian origin and 28/48 (58%) tumors of Finnish origin. 22/54 (41%) Egyptian tumors showed combined loss/deficiency of both $p15^{INK4b}$ and SMAD4, while $p15^{INK4b}$ was selectively lost/deficient with positive SMAD4 expression in 24/54 (44%) tumors. Loss of $p15^{INK4b}$ was associated with older age at presentation (>50 years) in the Egyptian tumors (p=0.04). These data show for the first time that $p15^{INK4b}$ loss of expression marks a subset of colorectal cancers and ethnic origin may play a role in this selection. In a substantial number of cases, the loss was independent of SMAD4 but rather associated with $p15^{INK4b}$ gene promotor hypermethylation and old age which could be related to different environmental exposures.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.343-349
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• 1990

The solubility of protein and phytate was measured at various pH's in distilled water and at various concentrations of NaCl, $CaCl_2\;and\;Na_2SO_3$ solutions, and then optimum condition for producing low phytate protein isolate from perilla flour was investigated. The protein solubility in water showed minimum at pH 4.0 and increased at pH higher or lower than 4.0, while phytate solubility was highest at pH 5.0 and decreased at pH higher or lower than 5.0. In NaCl solution, protein solubility was lowest between pH 3.0-4.0, while phytate solubility was high between pH 2.0-5.0 and abruptly decreased above PH 6.0. In $Na_2SO_3$ solution, protein solubility was lowest between pH 2.0-3.0 and phytate solubility showed maximum values between pH $5.0{\sim}6.0$, and it's solubility was low in 3% salt concentration at all pH ranges. In $CaCl_2$ solution, protein solubility in 3% salt concentration was relatively low at all pH ranges, and phytate solubility showed highest values between pH $2.0{\sim}3.0$ and abruptly decreased (1.0%) above pH 4.0. In order to make low phytate protein isolate, defatted perilla flour protein was extracted at pH9.0 and precipitated at pH 4.0 in 3% NaCl solution. The yield of low phytate protein isolate was 61.4% of total protein. This protein was found to contain 0.02% phytate by weight.

• Journal of the Korean Chemical Society
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• v.27 no.5
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• pp.340-344
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• 1983

It has been found that both of the iridium (Ⅰ) complexes, Ir$(ClO_4$)(AN)(CO)$(Ph_3P)_2$(AN = $CH_2$CHCN, $Ph_3P = (C_6H_5)_3$P) and [Ir(AN)(CO)$(Ph_3P)_2]ClO_4$, react with $Cl^-$ to give IrCl(AN)(CO)$(Ph_3P)_2$, and [Ir(AN)(CO)$(Ph_3P)_2]ClO_4$ dissociates AN to yield Ir$(ClO_4)(CO)(Ph_3P)_2$ in the absence of excess AN added, and Ir$(ClO_4)(CO)(Ph_3P)_2$ reacts with $Cl^-$ to produce IrCl(CO)$(Ph_3P)_2$. It is suggested that the catalytic polymerization of AN with Ir$(ClO_4)(AN)(CO)(Ph_3P)_2$ proceeds through the formation of [(CO)(Ph_3P)_2$Ir(-CH=CHCN)(H)($CH_2$=CHCN)]Cl$O_4$ followed by the formation of iridium(alkyl)(alkenyl) type complex which undergoes a reductive elimination to produce the polymer of acrylonitrile.

• Restorative Dentistry and Endodontics
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• v.37 no.1
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• pp.16-23
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• 2012

Objectives: Present study was undertaken to investigate the crystal growth onto synthetic hydroxyapatite (HA) seeds in pH 4.3 and pH 7.0 supersaturated solutions with different fluoride concentrations. Materials and Methods: 8 groups of pH 4.3 and 7.0 calcium phosphate supersaturated solutions were prepared with different fluoride concentrations (0, 1, 2 and 4 ppm). Calcium phosphate precipitates yield crystal growth onto the HA seed surface while solutions flow. For evaluation of crystallizing process, the changes of $Ca^{2+}$, $PO{_4}^{3-}$, $F^-$ concentrations of the inlet and outlet solutions were determined. The recovered solid samples were weighed to assess the amount of minerals precipitated, and finally determined their composition to deduce characteristics of crystals. Results: During the seeded crystal growth, there were significantly more consumption of $Ca^{2+}$, $PO{_4}^{3-}$, $F^-$ in pH 4.3 solutions than pH 7.0 (p < 0.05). As fluoride concentration increased in pH 4.3 solution, $Ca^{2+}$, $PO{_4}^{3-}$, $F^-$ consumption in experimental solutions, weight increment of HA seed, and fluoride ratio in crystallized samples were increased. There were significant differences among the groups (p < 0.05). But in pH 7.0 solution, these phenomena were not significant. In pH 7.0 solutions, analyses of crystallized samples showed higher Ca/P ratio in higher fluoride concentration. There were significant differences among the groups (p < 0.05). But in pH 4.3 solution, there were not significant differences in Ca/P ratio. Conclusions: Crystal growth in pH 4.3 solutions was superior to that in pH 7.0 solutions. In pH 4.3 solutions, crystal growth increased with showed in higher fluoride concentration up to 4 ppm.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.459-465
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• 1997

In order to extend the shelf-life of the low-salted Myungran-Jeot, before immersing alaska pollack roe, the salt solutions was adjusted to pH 7.0 and 4.7, respectively. pH during ripening was somewhat constant, whereas the content of lactic acid was slightly increased, and especially, that of pH 4.7 Myungran-Jeot was increased rapidly in the begining of fermentation period. $NH_2-N$ content of pH 4.7 Myungran-Jeot was increased with increasing fermentation period, whereas those of control and pH 7.0 decreased except the begining of fermentation period. The contents of TMA, TBA, and VBN of pH 4.7 were lower than those of control and pH 7.0. In addition, the mirrobial growth was significantly inhibited in pH 4.7 Myungran-Jeot. The estimated shelflives of control, pH 7.0, and pH 4.7 Myungran-Jeots were about 12, 12, and 16 days, respectively.

• Korean Journal of Microbiology
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• v.23 no.1
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• pp.9-12
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• 1985

As a part of the host cell development for a amplified recombinant trp operon, $aroP^-$ mutation was introduced in a E. coli host strain. $aroP^-$ mutation was induced by transposon Tn10 and transduced into the E. coli host cell by bacteriophage P1Kc. The effect of $aroP^-$ mutation on the excretion of tryptophan in E. coli $trpR^{-ts}/ColE_1 -trp^+$ cells was investigated. Mutant lacking the general aromatic transport system was resistant to ${\beta}-2-thienylalanine\;(2{\times}10^{-4}\;M)$, p-fluorophenylalanine $(2{\times}10^{-4}M)$, or 5-methyltryptophan $(2{\times}10^{-4}\;M.)[^3H]-tryptophan$ uptake of the $aroP^-$ mutant strain was reduced considerably as compared with $aroP^+$ counterpart. The rate of $[^3H]-tryptophan$ uptake of the $aroP^-$ mutant strain treated with $NaN_3(3{\times}10^{-2}\;M)$ was much less affected than that of $aroP^+$ counterpart. The $aroP^-$ transductants increased the tryptophan excretion from E. coli $trpR^{-ts}/ColE_1 -trp^+$ four times more than $aroP^+$ counterpart.

• Journal of Mushroom
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• v.4 no.2
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• pp.43-47
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• 2006

PMO-P4, being cultivated as "Sanghwang" in Korea, was proved to be P. baumii based on ITS (internal transcribed spacer) sequencing and RFLP (Restriction Fragment Length Polymorphism) patterns along with some Phellinus species including P. linteus. The similaraty of ITS sequencing between PMO-P4 and other Phellinus species was given the range of 48.6%~72.2%, showing the highest homology from P. linteus and the lowest from P. gilvus.