• Toxicological Research
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• v.16 no.4
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• pp.302-309
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• 2000

The purpose of this study is to investigate toxic effects of iso-butylalcohol (iBA) in Sprague-Dawley (SD) rats under the exposure of 6 hours a day, 5 days a week for 13 weeks by inhalation, and to evaluate the occupational safety of iBA in comparison with the permissible exposure level (PEL) stipulated by the Occupational Safety and Health Administration (OSHA). iBA did not induce any abnormal changes from the aspects of clinical signs, feed consumption, ophthalmic test, urinalysis, hematology and blood chemistry during and at the terminal of the inhalation toxicity tests. We did not find any abnormal findings in the gross and microscopic observations due to the inhalation of iBA. There was no alteration in relative organ weights by the inhalation of iBA. No observed adverse effect level (NOAEL) of iBA was considered to be more than 3,000 ppm in rats under the inhalation of 6 hours a day, 5 days a week for 13 weeks. Fifty ppm of iBA, the PEL regulated by OSHA, is too conservative for working places. As iBA showed no abnormal observations in all the experimental parameters at any concentration under this experimental condition, we suggest that 150 ppm is safe enough for the PEL of iBA in the working areas, even taking into onsideration that OSHA lowered the PEL to 50 ppm for fear of the probable risk of its skin irritation.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.1
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• pp.17-22
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• 2005

We examined whether the abnormal EEG state by NMDA receptor blocker MK-801 can be reversed by typical and atypical antipsychotics differentially by comparing their spectral profiles after drug treatment in rats. The spectral profiles produced by typical antipsychotics chlorpromazine (5 mg/kg, i.p.) and haloperidol (0.5 mg/kg, i.p.) were differ from that by atypical antipsychotic clozapine (5 mg/kg, i.p.) in the rats treated with or without MK-801 treatment (0.2 mg/kg, i.p.) which produce behavioral abnormalities like hyperlocomotion and stereotypy. The dissimilarity between the states produced by antipsychotics and the control state was examined with the distance of the location of the canonical variables calculated by stepwise discriminant analysis with the relative band powers as input variables. Although clozapine produced more different state from normal state than typical antipsychotics, clozapine could reverse the abnormal schizophrenic state induced by MK-801 to the state closer to the normal state than the typical antipsychotics. The results suggest that atypical anesthetic can reverse the abnormal schizophrenic state with negative symptom to the normal state better than typical antipsychotic. The results indicate that the multivariate discriminant analysis using the spectral parameters can help differentiate the antipsychotics with different actions.

• The Korean Journal of Financial Management
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• v.20 no.1
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• pp.61-92
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• 2003

As an extension of previous researches with the conclusion that the announcement of adopting stock options generates positive abnormal returns, this paper examined whether the abnormal return changes over time or varies depending on the number of stock options granted. Empirical analysis was made to find whether the announcement of stock option awards has the same response in the stock market from the early days when stock option plans had been introduced in the Korean stock market till today when it was widespread. Results indicate that the announcement effect had been on a gradual decline since 2000. In addition, it is found that if a company announces stock option awards several times, the abnormal return gradually declines in proportion of the number of stock options granted. This implies that as the stock option awards become widespread, the positive effect that the announcement of adopting stock options generates as news has been on a relatively steady decrease. In short, it leads to a conclusion that the more companies grant stock options, and the more stock options a company announces, the less impact it has on the increase in the firm's value.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.7
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• pp.3087-3091
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• 2014

Purpose: To determine the utility of digital rectal examination (DRE), serum total prostate specific antigen (tPSA) estimation, and transrectal ultrasound (TRUS) for the detection of prostate cancer (PCa) in men with lower urinary tract symptoms (LUTS). Materials and Methods: All patients with abnormal DRE, TRUS, or serum tPSA >4ng/ml, in any combination, underwent TRUS-guided needle biopsy. Eight cores of prostatic tissue were obtained from different areas of the peripheral prostate and examined histopathologically for the nature of the pathology. Results: PCa was detected in 151 (50.3%) patients, remaining 149 (49.7%) showed benign changes with or without active prostatitis. PCa was detected in 13 (56.5%), 9 (19.1%), 26 (28.3%), and 103 (74.6%) of patients with tPSA <4 ng/ml, 4-10 ng/ml, 10-20 ng/ml and >20 ng/ml respectively. Only 13 patients with PCa had abnormal DRE and TRUS with serum PSA <4 ng/ml. The detection rate was highest in patients with tPSA >20 ng/ml. The association between tPSA level and cancer detection was statistically significant (p<0.01). Among 209 patients with abnormal DRE and raised serum PSA, PCa was detected in 128 (61.2%). Conclusions: The incidence of PCa increases with increasing serum level of tPSA. The overall screening and detection rate can be further improved by using DRE, TRUS and TRUS-guided prostate needle biopsies.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3737-3740
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• 2014

Background: Abnormal uterine bleeding (AUB) is the most important symptom of endometrial hyperplasia and endometrial curettage (EC) is the gold standard diagnostic procedure. We present the results of patients who underwent EC for AUB and the efficacy of progestin administration in those with endometrial hyperplasia. Materials and Methods: A total of 415 female patients who presented to Duzce Public Hospital in 2011-2012 for AUB and who underwent EC were included. We determined the reasons for AUB, and females with hyperplasia were treated with 10 mg/day medroxyprogesterone acetate for 14 days/month or 160 mg/day megestrol acetate continuously for 3 months. We evaluated the efficacy of progestins for periods of three and/or six cycles by repeating EC. A statistical analysis of specific endometrial causes according to age of presentation was conducted using the chi-square test. Results: Among the 415 females (average age, 53.5 years) followed for 6 months, 186 had physiological changes (44.8%), 89 had simple hyperplasia (21.44%), 1 had atypical hyperplasia (0.2%), 6 had (1.44%) complex hyperplasia, 3 had (0.72%) atypical complex hyperplasia, and 5 had adenocarcinoma (1.2%). Regression rates were 72.7-100%, and the optimum results were observed after 6 months of hormonal therapy. Conclusions: The main cause of AUB was physiological change. Progestin therapy resulted in significant regression even in females with atypical hyperplasia.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.63-63
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• 2010

Using both experimental and theoretical approaches, we have investigated the adsorption properties of an organic molecule (HATCN), which is used in OLEDs as an efficient hole injection layer, on metal and inert surfaces. We have also studied the structural and electronic properties of such interfaces and the dependences on deposition thickness. We have observed different trends in work function changes with different surfaces. Our photoelectron spectroscopic measurements have revealed an abnormal phenomenon in HATCN on a metal (Cu) surface: the work function decreases at lower coverage (~monolayer) of HATCN on a metal (Cu) surface, but it increases back and becomes higher than that of a bare Cu surface at higher coverage. It has, on the contrary, been observed that the work function of graphene surface just increases as the HATCN coverage increases. Our first-principles density functional calculations has not only verified our experimental observations, but also disclosed the underlying mechanism of such abnormal and different work function behaviors. We have found that the change in work function results from mutual polarization induced by the geometrical deformation and the bond dipole formed at the interface due to the charge redistribution. At low coverage of HAT-CN on Cu substrate, the former reduces the work function significantly by pulling down the vacuum level, while the latter tends to push up the vacuum level resulting in the work function increase.

• Journal of Preventive Medicine and Public Health
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• v.25 no.1 s.37
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• pp.34-43
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• 1992

To investigate the effect of hyperoxia on EKG findings and to evaluate the applicability of EKG as noninvasive monitoring index of oxygen toxicity, 38 rabbits were continuously exposed to 6 different conditions-3 hyperbaric oxygenations (HBO-2.5, 3.5 and 5ATA, 100% $O_2$), normobaric oxygenation (NBO,100% $O_2$), hyperbaric aeration (HBA-5ATA, 21% $O_2$) and normobaric aeration (NBA, 21% $O_2$)-for 120 minutes and their EKG and time to dyspnea and convulsion were recorded. Dyspnea and death were observed in exposure conditions of HBO-3.5 and HBO-5 (Positive rate of dyspnea 10%, 100%, death : 10%, 25%, respectively) only, and convulsion in 4 oxygenation groups (NBO;20%, HBO-2.5;20%, HBO-3.5;20%, HBO-5;88%). Abnormal EKG findings included arrhythmia and ST-T changes and the incidences was increasing with doses(partial pressure of oxygen). In addition to EKG change, findings observed during exposure were dyspnea and convulsion in the order of appearance and when non specific ST-T change was accepted as positive(abnormal) finding, the frequency of abnormal EKG was statistically significant(p<0.01), but when it was excluded from positive results, the frequency of EKG change was not significant(p>0.05). These results suggest that the effect of hyperoxia on heart is myocardial ischemia and arrhythmia, that oxygenation more than 3.5ATA causes myocardial damage in 120 minutes exposure, and that EKG is valuable as monitoring index of oxygen toxicity.

• Journal of Embryo Transfer
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• v.24 no.2
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• pp.89-95
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• 2009

Successful in vitro embryo production heavily relies on the normal maturation and fertilisation of oocytes. We examined the normal and abnormal fertilisation of zebu cattle oocytes matured in vitro. Immature cumulus oocyte complexes (COCs) from zebu cattle ovaries at slaughter were matured in vitro (IVM) for 24 h. The oocytes were either fixed, stained and examined for nuclear changes or fertilised in vitro (IVF) with Percoll-separated, heparintreated spermatozoa (1.0 ${\times}$ $10^6$/mL) of zebu (n = 7) and crossbred bulls (n = 7). After 18 h of sperm-COCs co-incubation at $39^{\circ}$C with 5% $CO_2$ in humidified air, the presumptive zygotes were fixed, stained and examined for pronuclei. The number of oocytes retrieved per ovary was 5.4 ${\pm}$ 0.7. The percentage of matured oocytes was 73.0. The difference in motility of spermatozoa before and after Percoll seperation was significant (p<0.001). The percentages of normal and abnormal fertilisation (polyspermia and oocytes with one pronucleus) varied significantly depending on individual bulls (p<0.05). A protocol for IVF of IVM oocytes in Bangladeshi zebu cattle is developed. A future study may elucidate the capacity of such IVM-IVF oocytes to develop to the blastocyst stage for transfer to surrogate mother.

• Journal of Powder Materials
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• v.11 no.5
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• pp.383-390
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• 2004

In order to investigate behavior of abnormal expansion of the iron-copper compacts, we compared the dilatometric curves of the compacts which mixed the copper powder to the iron powder with those of compacts which mixed the copper powder to the iron-copper alloy powder. The dilatometric curves were obtained below the sintering conditions, which heated up to 115$0^{\circ}C$ by a heating rate of 1$0^{\circ}C$/min, held for 60min at 115$0^{\circ}C$ and cooled down at a rate of 2$0^{\circ}C$/min to room temperature. The dilatometric curves of the compacts showed the different expansion behavior at temperatures above the copper melting point in spite of same chemical composition. All of the compacts of former case showed large expansion, but all of the compacts in latter case showed large contraction. The microstructures of sintered compacts also showed the different progress in alloying of the copper into the iron powder. Namely we could observe the segregation at alloy part of copper into iron powder in case of the sintered compacts, which mixed the copper powder to the iron powder, but could not observe the segregation in compacts which mixed the copper powder to the iron-copper alloy powder. But the penetration of liquid copper into the interstices between solid particles was occurred at both cases. Therefore, the showing of the different dimensional changes in the compacts in spite of same chemical composition is due to more the alloying of copper into iron powder than the penetration of liquid copper into the interstices between solid particles.

• Korean Journal of Food Science and Technology
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• v.54 no.3
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• pp.343-350
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• 2022

In this article, we report a case study on the cause of abnormal fermentation of Takju based on a microbial community analysis of wheat-based Nuruk and Takju using next-generation sequencing. The microbial community showed notable changes during alcoholic fermentation. Members of the genera Aspergillus and Staphylococcus were dominant in Nuruk, whereas Saccharomyces, Pediococcus, Bacillus, Lactobacillus, and Enterobacter were predominant during Takju fermentation. In particular, members of the Enterobacter and Bacillus genera that were present were identified as the opportunistic pathogens B. wiedmannii and E. cloacae. The relative abundance of two species increased in Mitsul-3, wherein the concentration of organic acid rapidly decreased, and in Deotsul-1, in which raw materials were added. Furthermore, the relative abundance of lactic acid bacteria (LAB) in both the Nuruk and Takju was very low. Therefore, this result showed that the abnormal proliferation of E. cloacae and B. wiedmannii in Takju was due to the absence of LAB.