• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2003년도 한국우주과학회보 제12권2호
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• pp.78-78
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• 2003

Dwarf galaxies are the most common type of galaxy in the universe and believed to be basic building blocks of the large scale structures. In order to understand the formation history of these galaxies, we selected two well-observed galaxies in the Local Group and constructed the stellar population models including HB stars. We employed Y$^2$ Isochrones (Yi et al. 2001) and HB tracks (Yi et al. 1997) for stellar population synthesis. Our models show that (1) the Carina dSph has several distinct populations with age of ∼10.5, 5.8, 4.1, 2.8 and 1.0 Gyrs, and (2) stellar populations of the Sextans dSph are constructed in terms of the two populations with age of ∼ 11 and ∼2.5 Gyrs. Observational data were kindly provided by Lee et al. (2003, in preparation) and Monelli et al. (2003) for Sextans and Carina dsphs, respectively.

• 한국컴퓨터정보학회논문지
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• 제21권9호
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• pp.73-78
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• 2016

In 2014, Wuu et al. proposed a group key management scheme based on (2,2) secret sharing. They asserted that their scheme satisfies security requirements and mutual authentication. But this paper pointed out that their scheme does not satisfy mutual authentication and impersonating attack. In this paper, we describe the reasons and processes that a malicious group member can impersonate the Group Key Distributor. To fill the gaps, we discuss the problems, and propose an improved protocol.

• Natural Product Sciences
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• 제18권2호
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• pp.76-82
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• 2012

Stamens of Mesua ferrea L. are a well-known herbal drug used in Indian System of Traditional Medicine to treat various diseases. The claimed activity of this plant part is necessitated to investigate antioxidant and hepatoprotective activity. Authenticated plant sample was extracted with hexane, ethanol (EtOH) and water (aq.) using ASE 100 accelerated solvent extractor. Antioxidant activity was evaluated by means of different in vitro assays. Hepatoprotective effect was investigated on carbon tetrachloride induced oxidative stress in liver slice culture model. Cytotoxic marker lactate dehydrogenase (LDH) released in culture medium and the activity of lipid peroxidation along with antioxidant enzymes (AOEs) namely superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) were estimated. Hexane and EtOH extracts were significantly inhibited DPPH, NO, SOD and $ABTS^+$ radical in dose dependent manner. The trade of phenol content was: aq. extract < hexane extract < EtOH extract. A significant correlation was shown by total phenol content and free radical scavenging activity of extracts. The culture system treated with hexane extract, EtOH extract or ascorbic acid exhibited significant depletion in LDH, lipid peroxidation, antioxidative enzymes SOD, CAT and GR. Hexane extract and EtOH extracts of stamen of M. ferrea protected liver slice culture cells by alleviating oxidative stress induced damage to liver cells.

• Journal of Nutrition and Health
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• 제40권2호
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• pp.105-110
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• 2007

The study was designed to observe antioxidant activities of conjugated linoleic acid (CLA) by determining antioxidant enzyme protein levels [cytochrome P4502 El (CYP2E1), Copper, Zinc-superoxide dismutase (CuZn-SOD), glutathione peroxidase (CSH-Px), glutathione S-transferase (GST)] by Western blot analysis and the levels of ${\alpha}$-tocopherol and 2-thiobarbituric acid reactive substances (TBARS) in the liver of chronically ethanol-treated rats. Sixty Sprague Dawley male rats were divided into 3 groups (Control, EtOH, EtOH+CLA). All rats were fed Lieber-DeCarli liquid diet for 4 weeks by pair-feeding against the EtOH group. The liquid diet was supplemented with 1.77g CLA mixture per kg diet in the EtOH+CLA group. Isocaloric maltose dextrin was added in replace of 50g ethanol (36%kcal) for the Control group. Ethanol ingestion significantly increased the levels of CYP2E1 protein and TBARS, but significantly reduced CuZn-SOD protein level and increased GST protein level. There was no significant effect on the level of GSH-Px protein and ${\alpha}$-tocopherol in the liver by ethanol. CLA supplementation with ethanol significantly increased the levels of CuZn-SOD, GSH-Px and GST and also significantly attenuated TBARS level, whereas there was no significant effect on the levels of CYP2E1 protein and ${\alpha}$-tocopherol by CLA. Overall, the CLA supplemented to ethanol could significantly increase the levels of CuZn-SOD, GSH-Px and GST proteins and reduce the level of TBARS in the liver of chronically ethanol-treated rats.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.2976-2980
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• 2012

Nitrile-forming eliminations from (E)-2,4-$(NO_2)_2C_6H_2CH=NOC_6H_4-2-X-4-NO_2$ (1a-e) promoted by $R_3N$ in MeCN have been studied kinetically. The reactions are second-order and exhibit Br$\ddot{o}$nsted ${\beta}$ = 0.83-1.0 and ${\mid}{\beta}_{lg}{\mid}$ = 0.41-0.46. The results have been interpreted in terms of highly E1cb-like transition state with extensive $C_{\beta}$-H bond cleavage and limited $N_{\alpha}$-OAr bond cleavage. Comparison with existing data reveals that the structure of the transition state changes from E2-central to highly E1cb-like either by the change of the ${\beta}$-aryl group from Ph to 2,4-dinitrophenyl under the same condition or by the base-solvent system variation from $EtO^-$-EtOH to $Et_3N$-MeCN for a given substrate (1a-e).

• Clinical and Experimental Reproductive Medicine
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• 제13권2호
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• pp.101-112
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• 1986

It is now common practice to attempt ovarian hyperstimulation in vitro fertilization and embryo transfer (IVF-ET) to promote the development of multiple preovulatory follicles and to maximize the number of mature egg available. There are several drugs for hyperstimulation such as clomiphene citrate only, clomiphene citrate and human menopausal gonadotropin (HMG) and HMG only. Accumlated experience has shown that the hyperstimulation of the ovary in IVF-ET results in high pregnancy rate. But the hyperstimulation of the ovary in IVF-ET may cause the hyperandrogenism, so we must consider the adverse effect on pregnancy rate of the hyperandrogenism. Little is known about the functional significance of androgen for the follicular growth, however, the hyperandrogenism might interfere with oocyte maturation. The aim of the present investigation was to determine the serum profiles of estradiol, androstenedione and testosterone during the hyperstimulated menstrual cycles in IVF. The results were summarized as follows: 1. There was a gradual increase in the mean levels of serum estradiol, androstenedione, and testosterone approaching follicular maturation. 2. The mean serum estradiol levels in the hyperstimulated groups were significantly higher than that in the control group in late follicular phase and ovum retrieval (ovulation) day (p<0.01). 3. The mean serum androstenedione levels in the clomiphene citrate groups were significantly higher than that in the control group in late follicular phase (p<0.01). There was no statistically significant different in the mean serum androstenedione levels between the control group and the HMG group (p>0.05). 4. There was no statistically significant difference in the mean levels of testosterone among each group (p>0.05). 5. There was no statistically significant different in the mean levels of estradiol, androstenedione and testosterone between the fertilized patients and non-fertilized patients in clomiphene citrate and HMG group (p>0.05).

• Journal of Chest Surgery
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• 제20권1호
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• pp.1-12
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• 1987

Respiratory care with oxygen inhalation is often a necessity to maintain life, and it is one of the important therapeutic adjuncts in respiratory disease and in intensive care after surgery. However, it has been reported that oxygen toxicity occurs after prolonged exposure to 100% 0, [Smith, 1899; Kistler et al. 1967; Schaffner et al. 1967; Rowland and Newman, 1969. Subjective symptoms of oxygen toxicity include tracheal irritation, frequent cough, some burning sensation in the trachea, tachypnea, severe dyspnea, etc. [Welch, 1963; Fisher et al, 1968; Milier et al, 1970; Clark and Lambertsen, 1971; Sackner, 1975]. Pathologic findings are atelectasis, injuries to the pulmonary capillaries and hemorrhage in the alveoli in gross specimens. There can be inflammation, proliferation of fibrin, thickening of alveolar membranes, degeneration of collagen fibers and interstitial edema in the microscopic findings. [Penrod, 1956; Cedergren, 1959; Bean, 1965; Schaffner, 1967]. Dubois and colleagues [1961] found that the amount of pulmonary surfactant was decreased in oxygen toxicity and atelectasis followed by the decreased pulmonary surfactant. Many authors reported that vital capacity, inspiratory force, pulmonary compliance, pulmonary capillary blood flow and pulmonary elasticity were deceased and arteriovenous shunting increased. [Comroe et al, 1945; Fuson et al, 1965; Kistler et al, 1966; Knowles and Blenner-hassett, 1967; Barber et al, 1978]. Many human volunteers were examined after prolonged exposure in a high oxygenated chamber and there were a few reports on animals with oxygen toxicity, subjects including rabbits. Gas partial pressures of alveoli and arteries were measured in rabbits exposed to 100% $O_2$ and the alveolar-arterial gas gradients were analyzed, which is the basis for the study of oxygen toxicity. These rabbits were divided into two groups; rabbits under natural respiration, and second group under artificial respiration with a respirator. The alveolar $PO_2$ [$P]AO_2$] and $PCO_2$ [$PACO_2$], and the arterial $PO_2$ [$PaO_2$] were measured under varying $O_2$ pressures; 15% $O_2$, 21% $O_2$ and 100% $O_2$.

• Clinical and Experimental Reproductive Medicine
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• 제21권2호
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• pp.137-147
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• 1994

Controlled ovarian hyperstimulation(COH) for in vitro fertilization and embryo transfer(IVFET) often results in the production of more embryos than can be efficaciously transferred at one time. However, embryo cryopreservation provides a mechanism by which additional embryos can be stored for later thawing and transfer. From November, 1990 to October, 1992, we completed 42 transfer cycles of cryopreserved pronucleus(PN) l-cell embryos using the fixed protocol of hormonal replacement therapy in a physiological manner regardless of individual ovarian function. Artificial endometrial stimulation was performed with only exogenous estradiol and progesterone(E-P) in 36 transfer cycles (Group I) and with gonadotropin-releasing hormone agonist(GnRHa) and exogenous estradiol and progesterone(GEEP) in 6 transfer cycles(Group II ). The results were as follows. 1. The Survival rate of total cryopreserved-thawed embryos was 64.9%(198/305): 64.9% (172/265) in Group I and 65.0% (26/40) in Group II. 2. Total 168 embryos were transferred with an average of 4.7 per ET in Group I and total 26 embryos were transferred with an average of 4.3 per ET in Group II. 3. The pregnancy rate(PR) per cryopreserved-thawed ET and the implantation rate was 33.3 %(14/42) and 6.7%(13/194), respectively. The PRs per cryopreserved-thawed ET were 30.6% (11/36) in Group I and 50.0% (3/6) in Group II without significant difference. 4. The take home baby rate was 11.1%(4/36) in Group I and 33.3% (2/6) in Group II.

• 종양간호연구
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• 제9권2호
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• pp.136-144
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• 2009

Purpose: This study was to compare the differences in self-care behaviors between the group with fighting spirit and the group with helplessness. Methods: This study utilized a cross-sectional descriptive design. A total of 97 ambulatory cancer patients completed the Mental Adjustment to Cancer (MAC) scale by Watson et al. (1988) and Self Care Behaviors Scale by Oh et al. (1997). The data was analysed using frequency, percentage, t-test, ANOVA, Pearson's correlation and stepwise multiple regression. Results: Fighting spirit group were found to conduct self-care behaviors more compared to the helplessness group (t=3.346, p<.0001). The score of the self-care behaviors in fighting spirit group was 4.42 out of a total score of 7 and that of helplessness group was 3.85. There was a significant difference (p<.0001) in self-care behaviors according to the level of faith and performance status. Fighting spirit ($R^2$=0.120, p<.0001), performance status ($R^2$=0.078, p=.001) were predictive of self-care behaviors. Conclusion: Cancer patients' mental adjustment is correlated with the degree of self-care behaviors. Having fighting spirit is one of the most adaptive techniques that cancer patients could use in adjustment to the life with cancer.

• 대한예방한의학회지
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• 제2권1호
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• pp.45-54
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• 1998

The antilipidperoxidative and hepatopreventive effects of Houttuynia cordata extract(HCE) were investigated at the level of liver homogenates and serum of SD rats intoxicated EtOH(3g/kg for 3days). We measured MDA(malondialdehyde) in the live. homogenate, AST(1-aspartate-2-oxoglutarate aminotransferase) and ALT( 1-alanine-2-oxoglutarate aminotransferse) in the serum. The analysis of the measurement indicated that HCE reduced MDA, ALT and AST significantly and their reduction was in relation to dose dependence. In rat liver homogenate intoxicated with EtOH, HCE treatment group inhibited lipidperoxidation by 50-75%. In rat serum intoxicated EtOH, HCE inhibited AST and ALT by 40-70%.