• Journal of Chest Surgery
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• 제22권4호
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• pp.525-547
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• 1989

Hemorrhagic tendency observed in open heart surgery patients has been attributed, among other causes, to increased fibrinolytic activity during extracorporeal circulation. But the exact mechanism of enhanced fibrinolytic activity which occurs during extracorporeal circulation is still unknown. So, we studied and compared the changes of parameters of fibrinolytic and protein C system according to time obtained from the plasma of 31 adult open heart surgery patients[EGG group] and 10 adult general thoracic surgery patients[control group], in order to confirm the hypothesis that the activated protein C system might affect the fibrinolytic system during extracorporeal circulation. In ECC group, the nature of the enhanced fibrinolytic activity that evolved during extracorporeal circulation was characterized by significant increase in fibrin degradation products[P < 0.01] and significant decrease in plasminogen and alpha2-antiplasmin[P < 0.05, P < 0.01] in spite of adequate amount of heparin administration. These changes were most pronounced in the early phase of extracorporeal circulation and normalized after termination of extracorporeal circulation. The results of these observations were the same after volume correction with the value of hematocrit. The change of volume corrected protein C ratio during extracorporeal circulation revealed similar pattern to those of plasminogen and alpha2-antiplasmin [P < 0.01], but volume corrected ratio of free protein S showed significant increase after the commencement of extracorporeal circulation then decreased after extracorporeal circulation. Although the above mentioned changes occur similarly in both bubble type oxygenator-used and membrane oxygenator-used patients groups, but the degree of decrease was more severe in membrane oxygenator-used patients group [P < 0.01] and showed much slower recovery to reach to the preextracorporeal circulation level. These results confirm the hypothesis that the enhanced fibrinolysis during extracorporeal circulation might be caused by the activation of protein C system and the activation is possibly linked to the appearance of thrombin from contact activation of blood after wide exposure to the synthetic surfaces of extracorporeal circuit. Key words: Extracorporeal circulation, Enhanced fibrinolysis, Protein C system.

• 한국식품과학회지
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• 제16권1호
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• pp.41-46
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• 1984

Aspergillus niger sherumanni IAM 2059가 분비하는 펙틴질분해효소 중에서 endo-polygalacturonase 를 Sephadex G-100, DEAE-Sephadex A-50을 이용하여 분리하고 점도감소와 분해산물분석을 통해 효소의 특성을 조사하였다. Chromatography를 통해 얻은 3 개의 역가 fraction (F-A, F-I 및 F-II) 은 각각 exo형 효소, eodo-polygalacturonase, endo-polymethylgalacturonase 이었다. endo-polygalacturonase의 역가 최적 pH는 환원당 생성으로는 pH4.2 근방이었고 점도감도로는 pH4.7 근방이었다. 이 효소의 Z-value는 $7.5^{\circ}C$이고 $D40^{\circ}C$는 240sec 이며 $40^{\circ}C$에서 활성화엔트로피(Enthalphy of activation) 217.3KJ/mol, 활성화엔트로피(Entropy of activation) 409.2J/mol.K, 활성화자유에너지(Free energy activation) 89.2KJ/mol 이었다.

• 한국세라믹학회지
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• 제16권4호
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• pp.201-205
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• 1979

Domestic Yungil bentonite (montmorillonite) was treated with 1N sodium hydroxide solution in an autoclave at several temperatures, between 100 to 200℃, for 1 to 24 hrs. The products were examined by X-ray diffraction analysis. The following concecutive reaction was valid. montmorillonite→amorphous aluminosilicate→analcime The reaction rate constants k and k' at 200℃ were 0.35hr-1 and 0.22hr-1, respectively. The activation energies for the conversion from montmorillonite to amorphous aluminosilicate and from amorphous aluminosilicate to analcime were 10 kcal/mol and 12kcal/mol, respectively.

• The Korean Journal of Ceramics
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• 제5권1호
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• pp.35-39
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• 1999

For many years, alkali activated blast furnace slag cement containing no ordinary portland cement has received much attention in the view of energy saving and its many excellent properties. We examined the structural change of slag glass which was activated by alkali metal compounds using IR spectroscopy. The properties of hydrated products and unhydrated slag grains was characterized by XRD and micro-conduction calorimeter. Ion concentration change in the liquid during the hydration of blast furnace slag was also studied to investigated the hydration mechanism.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.861-865
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• 1991

In general, the fusion of neural network and fuzzy logic theory is based on the fact that neural network and fuzzy logic theory have the common properties that 1) the activation function of a neuron is similar to the membership function of fuzzy variable, and 2) the functions of summation and products of neural network are similar to the Max-Min operator of fuzzy logics. In this paper, a fuzzy-neural network will be proposed and a force controller of the robot gripper, utilizing the fuzzy-neural network, will be presented. The effectiveness of the proposed strategy will be demonstrated by computer simulation.

• 한국의류학회지
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• 제25권7호
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• pp.1293-1302
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• 2001

The purpose of this study was to investigate the characteristics of apparel purchase motivation in the sense of tonic activation. 746 female apparel consumers answered the questions about the apparel purchase motivation, apparel purchase behavior; frequency of apparel purchase and monthly clothing budget, and demographic variables. There were three factors in the apparel purchase motivation; preference of apparel shopping, priority of apparel purchase to other purchase to other products, interest in clothing. Apparel purchase motivation affected apparel purchase behavior especially in thee monthly clothing budget. Demographic variables such as age, income, education level, job status, and marital status affected apparel purchase motivation.

• 한국세라믹학회지
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• 제15권1호
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• pp.21-27
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• 1978

Hadong Kaolin (Halloysite) was granulated cylindrically and treated with 1N aqueous sodium hydroxide solution for 6-48 hrs at 60-10$0^{\circ}C$. The crystalling structure of surface of the products was studied by X-ray powder diffraction method. The reaction rate of halloysite to sodium A zeolite showed a gradual decrease from surface to inner layer. At the surface layer, the reaction mechanism was observed as first order consecutive reaction as follows: halloysitelongrightarrowamorphous aluminosilicatelongrightarrowsodium A zeolitelongrightarrowhydroxysodalite By applying the above reaction mechanism, the rate constants and activation energies was measured.

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2001년도 Korean Environmental Mutagen Society
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• pp.128-129
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• 2001

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.69.3-70
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• 2003

A substantial body of evidence indicates that reactive oxygen intermediates (ROIs) are implicated in pathogenesis of diverse human diseases, including cancer, diabetes and neurodegenerative disorders. Oxidative stress induced by ROIs often causes cell death via apoptosis that is regulated by a plenty of functional genes and their protein products. In the present work, we have investigated the role of bcl-2 in protecting against oxidative death induced by hydrogen peroxide in cultured rat pheochromocytoma (PC12) cells. (omitted)

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2003년도 추계학술대회
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• pp.192-193
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• 2003