• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.96-106
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• 2008

The purpose of this study was to identify the actual conditions of operation in school and investigate the perceptions of science teachers and students regarding the 7th elective-centered curriculum of high school science subjects. For this study, a questionnaire survey was conducted for the selected subjects including 127 high school science teachers and 763 high school students in their third year who had experienced the 7th elective-centered curriculum. As a result of the study, concerning the way to present the elective subjects of science, many cases were the alternative way and the group-elective way in humanity courses while natural science courses had the alternative way and the free-elective way in most cases. In other words, in many cases, the right of elective was given within a limited range. The result of the investigation on science teachers' perceptions on the elective-centered curriculum was that negative views dominated as a whole. Especially, earth science teachers showed the most negative attitudes. The number of biology and chemistry teachers who supported students' right to opt subjects were lower than that of physics teachers and earth science teachers who were against it. To help students make a right choice, many viewed that the system of the college Scholastic Ability Test should be complemented in order to prevent any disadvantage to each elective subject or that it was necessary to have systematic and realistic career education. As the result of investigating the perception of high school students in their third year regarding the elective-centered curriculum, they were usually not very satisfied with it. As the reason for it, many said the selection right was limited. Many others also expressed that there were lack of public relations and education on subjects and careers. Based on these results, limits still exist in accepting all demands although there are a lot of efforts made to smoothly adjust supply and demand of science teachers as well as students' electives in the field of school. It is considered necessary to come up with counterplan and complements to prevent basic science from being neglected or lower academic achievement in the subject of science from happening, and at the same time to harmoniously deal with supply and demand of science teachers as well as the issues of students' demands given the actual conditions of school.

• Korean Journal of Agricultural Science
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• v.3 no.1
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• pp.77-84
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• 1976

The preservation efficiency, quality and utilization of silage from 3 species of pumpkins (Mammoth pumpkin, Queensland blue pumpkin, Korean pumpkin) without and with 10, and 20% wheat bran additive were studied in this experiment. Silages were analysised and tested the chemical composition, pH and quality of silages between at 40-60 days and egg performance were carried out with mammoth pumpkin silage without additive. The results were summaried as follows. 1. The losses of all silage ware lower and similar as about 15% at 6 monthes following after silage-making but all raw pumpkins were spoilaged during the winter storaging. 2. The moisture content of silages were higher as about 97% in mammoth pumpkin silage, 94% in Queensland pumpkin silage and 91% in Korean pumpkin silage without additive and all nutrient content of silage without and with additive were depended on its content of raw silage material of pumpkins and wheat bran. The contents of moisture and N-free extract were slightly decrease but not significantly difference during the silaging and other contents were not so much changed. 3. Good quality of silage were made from all pumpkins with and without additive. Organic acid contents were 2.09-2.93% of lactic acid, 0.68-1.71% of acetic acid and 0% of butyric acid and it was pH 3.8-4.0 in silages. 4. Feed intakes, egg production and quality of egg were showed good result in 5.0 and 7.5% silage feeding group as D.M. base for egg performance. (P<0.01) 5. It was concluded that good quality of silage were made from pumpkins with and without wheat bran additive and it was suggested that poor quality feedstuff may be improved it feeding value by extended palatability with pumpkin additive silage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.496-504
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• 1997

This study was carried out to estimate toxic effects of phenol on survival and metabolism of the abalone juvenile, Haliotis discus hannai. The experiment was conducted by renewal bioassay procedure with different salinities at $20^{\circ}C$. The $LC_{50}$ of the juvenile exposed to phenol in the range of 0.5 and $100mg/\ell\;was\;34.3\~6.5mg/\ell\;at\;2.4\%_{\circ}\;and\;52.2\~9.3m/\ell\;at\;32\%_{\circ}$ salinity with exposure time from 24 hours to 96 hours. $LT_{50}$ was remarkablely reduced with increase of phenol conentration and decrease of salinity. Lethal toxicity or phenol was higher at low salinity than at high salinity. Therefore, salinity is likely to be one of factor to increase phenol toxicity. The oxygen consumption of the juvenile was reduced with increase of phenol concentration and with decrease of salinity. In spite of phenol toxicity, the oxygen consumption of the juvenile exposed to phenol of low concentration was high and similar as compared with that of control group. Survival rates of the abalone kept in phenol-free sea water after exposure to phenol concentration of 5, 10 and $20mg/\ell$ for 96 hours were reduced with decrease of salinity. Durations required to recover the normal metabolic rate of the juvenile, which was exposed to phenol concentration of 5, 10 and $20mg/\ell$ for 96 hours, were made longer with increasing phenol concentration. In the case of the juvenile exposed to sublethal concentration of phenol for 15 days, it were elongated as compared with that of the abalone exposed to phenol concentration caused acute toxicity. The result of this experiment indicated that relatively low concentration of phenol can impact on the abalone juvenile in marine ecosystem.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.351-359
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• 2014

A beverage was produced by the fermentation of mixed extracts from the various fruits, vegetables, algae, and medical herbs. The physicochemical properties of the fermented beverage of plant extracts (FBPE) and microbial diversity were analyzed in cultures enriched from FBPE using 16S and 26S rRNA gene sequence analyses. The pH, acidity, $^{\circ}brix$, reducing sugar, and alcohol contents of the FBPE were determined to be the 3.48, 1.68%, 70.0, 1,026 g/L, and 3.5%, respectively. The most abundant free sugar and organic acid in the FBPE were glucose (567.83 g/L) and tartaric acid (93.68 mg/L), respectively. Lactobacillus homohiochii was the predominant species in all enriched culture samples: 100% of the species in 0B (0% sugar) and 40B (40% sugar) libraries and 95.6% of 20B library (20% sugar). Lactobacillus fructivorans was detected in the 20B library. The predominant species in the samples of enrichment cultures collected from FBPE with three different sugar concentrations were: Candida zeylanoides (45.2%) in the 0Y library (0% sugar), Candida lactis-condensi (35.7%) and C. zeylanoides (35.7%) in the 20Y library (20% sugar), and C. lactis-condensi (38.1%) in the 40Y library (40% sugar). This result may provide a useful frame of reference for further analyses of microbial population dynamics in FBPE.

• Journal of the Korean association of regional geographers
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• v.6 no.2
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• pp.21-40
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• 2000

The retail trades in many countries have changed recently according to the high quality, diversification, and marked individuality of consumer needs. Under the continually competing system of the WTO agreement, corporations based in the USA and the EU try to raise their market share in other countries so it is inevitable for Korean retail enterprises to compete with them. This paper is aimed at contributing to the efficient growth for Korean retail trade from the analysis of the development process in retail trade and its changing locations comparing Korea and the USA. Retailers in the USA have practiced diversified marketing strategies considerably in order to survive in a rapidly changing retailing environment. American retailing, which has the most advanced marketing system in the world, has been of growing concern to marketing strategies in Korea. The following is a brief summary of this study. 1. Speedy and higher quality consumption is needed in accordance with the great increase in the single-family household and the female labor force participation both in Korea and in the USA. Senior citizens have become a new consumer group due to the aging population. In the future the retail trade will switch over to diversified retail formats and internet shopping as countries are transformed into information and communication societies. 2. In Korea, the former retail system characterized by markets and department stores has been greatly changed since the late 1980s with emphasis on high quality and convenience in consumption behaviors, with large domestic enterprises and foreign distribution corporations participating in Korean retailing. In the USA, retailing mergers and takeovers by major retails, bankruptcies, and extra-large shopping centers have emerged since the late 1980s. Recently, the USA retailing formats have been changed from the lower price-oriented discount types to the large scale theme parks. Much emphasis was put on entertainment, resorts, and convention centers. On the other hand, non-store types, such as the internet shopping, the CATV shopping, as well as catalog and mail-order sales are drastically increasing, although the proportion of their sales is low up to now. 3. In Korea, most of the retail facilities are concentrated in Seoul and the Metropolitan Region, and the distribution ratio of facilities came to 52% in 1997. The periodic markets, traditional markets which open on a periodic basis, are located mainly in Chollanam-do and Kyungsangbuk-do. The large-sized discount stores have expanded their locations to the over-crowded apartment complexes in new towns, located in the Metropolitan Region, and the large provincial cities, unlike the suburban locations in the USA. Therefore we needed to give attention to the locational relations in retail facilities between Seoul & the Metropolitan Region and rural settlement areas. In the USA, urban areas grew quickly with the development of the automobile in the 1920s, and the location of stores changed from a dispersed style centering around rural areas to a centralized one in urban areas. There is an accelerated growth for suburban areas, which have grown rapidly since 1950. As the membership warehouse clubs were introduced in the 1970s, the decentralization of location was more intensified. On the other hand, inner cities were revitalized by rearranging existing facilities to cope with suburban areas. And the location-free virtual retailing & TV shopping are also growing every year. 4. In view of the above, the continuous and desirable development devices in Korean retail trade are summarized as follows: First, the countermeasures against economies of scale, increase in retailing sales, and rise of a employment percentage in retailing are in need. Second, a scheme of lowering the proportion of food retail sales, and increasing a ratio of durable goods sales need to be worked out. Third, the original ideas are needed to apply positively information, communication and technology to retailing, to graft the traditional types on modem ones based on the social culture. Fourth, strategies are needed to strengthen the competitiveness of our retail trade through cooperation and chains of smaller retailers, the large enterprises participating in the distribution industry. Fifth, in order to realize the above, the retail industry, the administration, and the academic world should support the retail segment with concern and a practical strategy plan.

• The Korean Journal of Pharmacology
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• v.22 no.2
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• pp.79-87
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• 1986

Recently it has been shown that central dopaminergic system regulates the renal function and that intracerebroventricularly (icv) administered dopamine (DA) produces antidiuresis and antinaturiuresis, resembling icv norepinephrine, and evidence has been accumulated which would suggest the involvement of adrenergic system in the DA effects. It was attempted therefore in this study to see whether the DA effect is influenced by pretreatment of yohimbine which is known as a specific ${\alpha}_2-adrenoceptor$ antagonist. Yohimbine produced, when given icv in doses of $100\;{\mu}g/kg$, marked antidiuresis and antinatriuresis along with decreases in renal perfusion and glomerular filtration. DA, in doses of $15\;{\mu}g/kg$, also produced antidiuresis and antinaturiuresis. However, after yohimbine-pretreatment DA $15\;{\mu}g/kg$ improved renal hemodynamics, and electrolyte excretion and urine flow rate transiently increased. With $150\;{\mu}g/kg$ DA, the antidiuresis was more marked in the control group. But the yohimbine-pretreated animals responded with marked diuresis and natriuresis, sodium excretion increasing more than three-fold, which lasted for 20 minutes. $K^+-excretion$, osmolar clearance as well as free-water reabsorption increased. Renal hemodynamics improved partly. Apomorphine, a DA agonist, when given icv in doses of $150\;{\mu}g/kg$, produced diuresis and naturiuresis, concomitant with increased renal hemodynamics. Yohimbine-pretreatment however did not abolish the apomorphine-induced diuresis and naturiuresis. Antidiuresis and antinatriuresis elicited by norepinephrine, $10\;{\mu}g/kg$, was not affected by yohimbine-pretreatment. These results indicate that the renal effects of icv DA is not so simple as those of norepinephrine, and the diuretic natriuretic cffect which had been masked by the hemodynamic effect becomes manifest only when the decreases in hemodynamics were removed by the pretreatment of yohimbine. It was further suggested that those DA receptors which mediate the natriuretic response to icv DA is not affected by yohimbine, whereas those receptors involved in the decrease in renal hemodvnamics are blocked by yohimbine. And the possibility of involvement of adrcnergic system in the DA action is not substantiated.

• Radiation Oncology Journal
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• v.22 no.4
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• pp.307-315
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• 2004

Purpose: The purpose of this work was to study the differences of cyclooxygenase (COX-2) expression between Korean and Caucasian patients with early-onset breast carcinoma by immunohistochemistry. The test were analyzed to find a correlation between COX-2 and other biomarkers including HER-2/neu amplification, because we previously reported that a significant difference had been found in the expression of HER-2/neu between the two races. Furthermore, we investigated prognostic significance of COX-2 in korean patients. Materials and Methods: Sixty Korean women who were diagnosed breast carcinoma at 45 years old or younger and 60 Caucasian women with breast carcinoma were selected for this study. The median age of both groups was 37 years and tumor sizes were distributed evenly between the two group. Paraffin embedded blocks of primary tumor were processed for immunohistochemical staining of COX-2. The COX-2 expression was evaluated according to the percentage of positive cells and the intensity of staining. And the results were compared with the data of the previous studies to find correlation between COX-2 and other parameters and survival data. Results: Proportion of the COX-2 expression in total patients was $27.6\%$. The percentage of tumors that stained positive for COX-2 in korean and Caucasian women with early-onset breast carcinoma were $37.9\%$ and $20.8\%$, respectively. The difference was statistically not significant(p=0.090). Expression of COX-2 was not associated with several clinicopathologic parameters including HER-2/neu overexpression, but negative estrogen receptor status was correlated with significance (p=0.046). The 5 year disease free survival rate for patients with COX-2 expression was $67.9\%$, compared to $81.9\%$ of the COX-2 negative patients and the result was statistically not significant. Conclusions : A significant difference was not found in the expression of COX-2 between the two groups of patients with early-onset breast carcinoma. And correlation between COX-2 and other parameters was not observed except estrogen receptor negativity. Large scaled further research including radiotherapy factors will be needed to identify COX-2 as a prognostic role in patients with early-onset breast carcinoma.

• The Korean Journal of Nuclear Medicine
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• v.36 no.6
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• pp.333-343
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• 2002

Purpose: A new linker, hydrazino nicotinamide (HYNIC), was recently introduced for labelling of liposome with $^{99m}Tc$. In this study we synthesized HYNIC derivatized PEG (polyethylene glycol)-liposomes radiolabeled with $^{99m}Tc$. Materials and Methods: In order to synthesize HYNIC-DSPE (distearoyl phosphatidyl ethanolamine) which is a crucial component for $^{99m}Tc$ chelation, first of all succinimidyl 6-BOC-hydrazinopyridine-3-carboxylic acid was synthesized from 6-chloronicotinic acid by three sequential reactions. A DSPE derivative of succinimidyl 6-BOC-hydrazinopyridine-3-carboxylic acid was transformed into HYNIC-DSPE by HCI/dioxane. HYNIC-PEG-liposomes were prepared by hydration of the dried lipid mixture of EPC (egg phosphatidyl choline): PEG-DSPE : HYNIC-DSPE:cholesterol (1.85:0.15:0.07:1, molar ratio). The HYNIC-PEG-liposomes were labeled with $^{99m}Tc$ in the presence of $SnCl_2{\cdot}2H_2O$ (a reducing agent) and tricine (a coligand). To investigate the level of in vivo transchelation of $^{99m}Tc$ in the liposomes, the $^{99m}Tc$-HYNiC-PES-liposomes were incubated with a molar excess of DTPA, cysteine or glutathione solutions at $37^{\circ}C$ for 1 hour. The radiolabeled liposomes were also incubated in the presence of human serum at $37^{\circ}C$ for 24 hours. Results: 6-BOC-hydrazinopyridine-3-carboxylic acid was synthesized with 77.3% overall yield. The HYNIC concentration in the PEG-coated liposome dispersion was 1.08 mM. In condition of considering the measured liposomal size of 106 nm, the phospholipid concentration of $77.5\;{\mu}mol/m{\ell}$ and the liposomal particle number of $5.2{\times}10^{14}$ liposomes/ml, it is corresponded to approximate 1,250 nicotinyl hydrazine group per liposome in HYNIC-PEG-liposome. The removal of free $^{99m}Tc$ was not necessary because the labeling efficiency were above 99%. The radiolabeled liposomes maintained 98%, 96% and 99%, respectively, of radioactivity after incubation with transchelators. The radiolabeled liposomes possessed above 90% of the radioactivity in serum. Conclusion: These results suggest that the HYNIC can be synthesized easily and applied in labelling of PEG-liposomes with $^{99m}Tc$.

• Journal of Hospice and Palliative Care
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• v.7 no.1
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• pp.37-48
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• 2004

Purpose: Population using complementary and alternative medicine (CAM) and the cost or it are increasing all over the world. In this study, we investigated the utilization state of CAM in the elderly people during the last 6 months of life. Methods: We found 4,210 persons in Seoul, older than 65 years who received a funeral subsidy from health insurance after death during the latter half of the year, 2001. We stratified them by age and gender and selected 301 persons and surveyed them by questionnaire. Results: 247 persons (83.1%) used at least one of CAM during their last 6 months of life. Diet and Nutrition remedy showed the highest utilatization rate (65.5%), and drug therapies also were much used (29.9%). Utilization rate was higher in female (60%) and according to the cause of death, the highest in a geriatric disease groups, and the lowest in the cancer group. Whole satisfaction to CAM was high with average 4.25 points out of total 6, and adverse effects were almost free with average 5.55 points out of total 6. Satisfaction was the highest in Diet and Nutrition remedy but the lowest in Manipulative and Body-Based methods. Adverse-effect score was best in Manipulative and Body-Based methods. According to age and the causative disease of death, there were significant differences in satisfaction and adverse effect levels. Conclusion: Majority of old people used at least one of CAM during their last 6months of life. Whole satisfaction and adverse-effect level were very excellent.

• Journal of Korean Neurosurgical Society
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• v.64 no.6
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• pp.983-994
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• 2021

Objective : The effectiveness of gamma knife radiosurgery (GKR) in the treatment of brain metastases is well established. The aim of this study was to evaluate the efficacy and safety of maximizing the radiation dose in GKR and the factors influencing tumor control in cases of small and medium-sized brain metastases from non-small cell lung cancer (NSCLC). Methods : We analyzed 230 metastatic brain tumors less than 5 mL in volume in 146 patients with NSCLC who underwent GKR. The patients had no previous radiation therapy for brain metastases. The pathologies of the tumors were adenocarcinoma (n=207), squamous cell carcinoma (n=18), and others (n=5). The radiation doses were classified as 18, 20, 22, and 24 Gy, and based on the tumor volume, the tumors were categorized as follows : small-sized (less than 1 mL) and medium-sized (1-3 and 3-5 mL). The progression-free survival (PFS) of the individual 230 tumors and 146 brain metastases was evaluated after GKR depending on the pathology, Eastern Cooperative Oncology Group (ECOG) performance score (PS), tumor volume, radiation dose, and anti-cancer regimens. The radiotoxicity after GKR was also evaluated. Results : After GKR, the restricted mean PFS of individual 230 tumors at 24 months was 15.6 months (14.0-17.1). In small-sized tumors, as the dose of radiation increased, the tumor control rates tended to increase (p=0.072). In medium-sized tumors, there was no statistically difference in PFS with an increase of radiation dose (p=0.783). On univariate analyses, a statistically significant increase in PFS was associated with adenocarcinomas (p=0.001), tumors with ECOG PS 0 (p=0.005), small-sized tumors (p=0.003), radiation dose of 24 Gy (p=0.014), synchronous lesions (p=0.002), and targeted therapy (p=0.004). On multivariate analyses, an improved PFS was seen with targeted therapy (hazard ratio, 0.356; 95% confidence interval, 0.150-0.842; p=0.019). After GKR, the restricted mean PFS of brain at 24 months was 9.8 months (8.5-11.1) in 146 patients, and the pattern of recurrence was mostly distant within the brain (66.4%). The small and medium-sized tumors treated with GKR showed radiotoxicitiy in five out of 230 tumors (2.2%), which were controlled with medical treatment. Conclusion : The small-sized tumors were effectively controlled without symptomatic radiation necrosis as the radiation dose was increased up to 24 Gy. The medium-sized tumors showed potential for symptomatic radiation necrosis without signifcant tumor control rate, when greater than 18 Gy. GKR combined targeted therapy improved the tumor control of GKR-treated tumors.