• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.89-89
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• 2006

Polyalkylene phosphates - polymers that are built on the repeating unit of the diester of phosphoric acid: -[OP(O)(OH)Oalkylene]-, are known to form backbones of nucleic and teichoic acids. Various synthetic ways will be reported for the synthesis of the bare chains, where "alkylene" in the formula above means mostly two or three methylene groups. Some other structures have also been prepared. Several applications of these polymers are to be discussed, namely as liquid membranes, as components of two-block copolymers (ionic-nonionic diblock dihydrophilic) used as modifiers of CaCO3 crystallization, and as components of the inorganic-polymer hybrid materials. Some other applications in the biomedical field will also be discussed.

• 한국임상수의학회지
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• 제21권3호
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• pp.248-252
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• 2004

DNase activity from infective larvae of the parasitic nematode Haemonchus contortus was characterized and compared to that from whole worm. DNase activity from infective larvae was detected throughout pHs 4-10, but high activity was detected under acidic conditions. The activity was not inhibited by 10 mM EDTA at pH 5.0, but was significantly inhibited at pH 7.0. The activity produced DNA, fragments with mixtures of 3'-hydroxyls (OH) and 3'-phosphates (P) at each pH with predominance of 3'-P. A unique DNase activity at 37 kDa was identified from infective larvae on zymograms. The 37 kDa DNase was detected only at pH 5.0, but not at pH 7.0, and this activity was not inhibited by EDTA at pH 5.0. These characteristics of the 37 kDa infective larval DNase resemble those of classic acidic DNases (e.g., DNase II). In contrast, 34, 36 and 38.5 kDa DNase activities were shown to be specific for whole worm. This result demonstrated that DNases in H contortus are regulated during development.

• 한국임상수의학회지
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• 제16권2호
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• pp.501-505
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• 1999

Two dogs were presented urinary disorder in the associated with urolithiasis. Clinical signs were increased frequency of urination with mild straining pollakiuria, general depression and anorexia. On physical examinations, the pain was revealed at the palpation of the urethral area. Urinalysis showed high specific gravity, high pH, and triple phosphates. Radiography showed an increased radiopacity, and ultrasonography showed hyperecho in the just behind of os penis. Urolithiasis was diagnosed on the basis of clinical signs, radiography, and ultrasonography. In the prescrotal urethrotomy, urethra on the midline was incised and uroliths were eliminated. After elimination of uroliths, incision area was closed with 4-0 synthetic absorbable suture. In postoperative, there was good prognosis without hemorrhage, inflammation, and urethral stricture.

• 한국물환경학회지
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• 제24권3호
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• pp.285-290
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• 2008

This study was done to explain the role of limestone which might intervene in the phosphorus cycle in a lake. The effects of limestone on the dissolution of phosphate were estimated by simulations with the computer model Visual MINTEQ, which is designed for the chemical equilibrium calculations. According to the calculations limestone shows remarkable effects for the suppression of phosphate dissolution. The limestone can suppress the dissolution of phosphates by sacrificing themselves to acids, and as a consequence can increase the hardness and alkalinity of the lake. Both hardness and alkalinity play an important role in reducing soluble P and thus alleviate the eutrophication potential.

• Journal of Radiation Protection and Research
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• 제45권1호
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• pp.11-15
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• 2020

Background: There have been various studies to investigate the mechanisms of DNA damage from low-energy electrons. To understand the mechanism of these strand breaks, it is necessary to investigate the dissociation mechanism of the DNA constituents, that is, bases, sugars, and phosphates. Materials and Methods: We studied the dissociation of thymine base upon interaction with low-energy electrons. For this experiment, thymine powder was pressed onto the indium base and irradiated by 5 eV electrons. Results and Discussion: Non-irradiated and irradiated thymine samples were compared and analyzed using the X-ray photoelectron spectroscopic technique to analyze the dissociation patterns of the molecular bonds after low-energy electron irradiation of thymine. Conclusion: With 5 eV electron irradiation, C-C and N-C = O bonds are the primary dissociations that occur in thymine molecules.

• Journal of Oral Medicine and Pain
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• 제20권1호
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• pp.7-18
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• 1995

The Purpose of this article is to describe the biochemical properties and biological functions of several salivary proteins that possess the unusual properties of inhibiting spontaneous and secondary precipitation of calcium phosphate. This function is very important since human salivary secretion is supersaturated with respect to calcium phosphate. Biological function of statherin, proline rich protein (PRP) and histidine rich protein (HRP) is to inhibit precipitation of calcium phosphate in salivary glands, in the oral fluids, and onto tooth surfaces. The resulting supersaturated state of the salivary secretions contributes a protective and reparative environment which is important for the integrity of the tooth. Beneficial consequences of salivary supersaturation with respect to calcium phosphate are selectively expressed in the oral cavity- that is, protection is provided for the dental enamel-while undesirable consequences, for example, precipitation of calcium phosphates in the salivary glands and onto the teeth do not occur. Purification and structural characteristics of these proteins as well as clinical significance of functions of each protein will be discussed.

• Archives of Pharmacal Research
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• 제15권4호
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• pp.343-346
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• 1992

The synthesis of 6-aza-3', 5'-p-nitrophenylphosphoryltrioxy-2'-azido-2'-deoxy-2', 3' secouridine and 6-aza-3', 5'-phosphoryltrioxy-2'-azido-2'-deoxy-2', 3'-secouridine ammonium salt are described and they were evaluated for antiviral activity primarily against DNA and RNA viruses and found to be inactive, but no significant cytocidal effect was observed against Vero and Hela cell.

• 한국식품영양학회:학술대회논문집
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• 한국식품영양학회 2004년도 하계 학술 심포지엄
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• pp.48-48
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• 2004

Shiitake mushroom contained numerous nutrients, special flavor (lenthionine) and taste. In Asia, they are thought to have numerous medical properties f3r several diseases such as diabetes, anemia, tumors. Phosphates are known to increase hydration and water binding, stabilize meat emulsions, improve juiciness and tenderness, provide mineral supplementation, and maintain flavor of processed meat products. A lexicon f3r describing the texture and flavor of cooked pork patties were developed. (omitted)

• 한국연초학회지
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• 제3권2호
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• pp.129-130
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• 1981

The potato tuberworm, Phthorimaea operculella, is an occasional pest to tobacco plants in southern regions of Korea. In order to screen effective pesticides against the worm in tobacco leaves, pot and field experiments were carried out in 1981. In the pot experiment with a tobacco variety, Hicks, several effective organic phosphates (Dimecron- LQ 50, Dursban-WP 25, Ekalux-EC 25. Elsan-EC 47.5, and EPN-EC 45), out of 9 Pesticides tested, were solecte4 from their high mortality of more than 90%. Among these Pesticides Ekalux- EC 25 and Elsan- EC 47.5 were recommended to tobacco growers from their excellent efficacy in the field experiment with a tobacco variety, Burley 21.

• Mycobiology
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• 제28권3호
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• pp.119-122
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• 2000

Phytases (myo-inositol hexakisphosphate phosphohydrolase; EC 3.1.3.8) are enzymes which catalyze the hydrolisys of phytate into myo-inositol and inorganic phosphates. Phytases are found in plants and a variety of microorganisms. Aspergillus species were treated with 254 nm of UV irradiation for the screening of phytase overproducing mutant strains. At 15 minute irradiation, the survivals of population were less than 5%, and UV irradiation time was decided at 20 minute for the isolation of mutant strains. Four UV mutant strains in A. oryzae (YUV-47, -169, -341, -511) and six in A. ficuum (FUV-17, -36, -69, -193, -317, -419) were isolated on PSM media containing ammonium phosphate. The specific enzyme activities of A. ficuum mutants are 110 to 140% higher than that of wild type.