• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1153-1157
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• 2011

A kinetic study is reported for aminolysis of S-4-nitrophenyl X-substituted thiobenzoates 3a-g in 80 mol % $H_2O$/20 mol % DMSO at $25.0{\pm}0.1^{\circ}C$. Thiol esters 3a-g are 7.8-47.6 fold more reactive than the corresponding oxygen esters (i.e., 4-nitrophenyl X-substituted benzoates 1a-g). Such reactivity order appears to be in accordance with the expectation that 4-nitrothiophenoxide in 3a-g is a better nucleofuge than 4-nitrophenoxide in 1a-g since the former is 2.64 pKa units less basic than the latter. Hammett plot for the reactions of 3a-g exhibit poor correlation coefficients ($R^2$ = 0.977-0.986) with negative deviation by substrates possessing an electrondonating group (EDG), while the Yukawa-Tsuno plots result in excellent linear correlation ($R^2$ = 0.995-0.997) with ${\rho}$ = 0.93-1.23 and r = 0.57-0.67, indicating that the negative deviation shown by substrates possessing an EDG is caused by ground-state stabilization through resonance interactions but not due to a change in ratedetermining step upon changing the nonleaving-group substituent X. The ${\rho}$ value increases as the incoming amine becomes more basic and more reactive, indicating that the RSP is not operative in the current reactions.

• Journal of Pharmaceutical Investigation
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• 제23권2호
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• pp.111-118
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• 1993

The hemolytic characteristics of amphotericin B-containing liposomes have been investigated in vitro. From the hemolysis of human erythrocytes against free and liposomal amphotericin B, the marked reduction in the toxicity of amphotericin B was observed by incorporating the drug in egg PC liposomes. For 45 min, free amphotericin B at $9.6\;{\mu}g/ml$ could completely lyse 2 wt% human erythrocytes. However, liposomal amphotericin B had essentially no lytic effect even in the range over $9.6\;{\mu}g/ml$. In the 66 hr-hemolysis experiment, liposomal amphotericin B showed the slowly hemolysing chracteristics during the experimental period regardless of the concentration of amphotericin B but rapid hemolysis only for 12 hr was observed in the case of free amphotericin B and the degree of hemolysis for 12 hr was maintained after that time. Also the hemolysing ability of liposomal amphotericin B at $4\;{\mu}g/ml$ was lower than that of free amphotericin B at the same concentration for 66 hr. On the other hand, the dependence of hemolysis on amphotericin B contents in egg PC liposomes was significant between 1.64 mole% amphotericin B-containing liposomes and 15.79 or 27.27 mole% amphotericin B-containing liposomes. But no marked difference in hemolysis was observed between 15.79 and 27.27 mole% amphotericin B-containing liposomes. Especially, cholesterol as an excipient in amphotericin B-containing liposomes significantly reduced the hemolysis of human erythrocyte. The degree of hemolysis in 5 mole% amphotericin B-containing liposomes was reduced to approximately 50% of value in the cholesterol-free liposomes by adding 50% cholesterol.

• 대한교통학회지
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• 제29권6호
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• pp.17-23
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• 2011

$CO_2$ 배출량은 차량의 속도와 관련이 있으며. 속도는 도로의 종류에 따라 다르게 나타난다. 그러므로 단속류 간선 도로의 차량 당 $CO_2$ 배출량은 교차로 특성과 지정체의 영향을 받을 가능성이 많다. 따라서 교차로의 존재, 지정체의 영향과 차량 당 $CO_2$ 배출량의 분석이 필요하다. 연구 방법은 첫째, 국도를 대상으로 차량의 교차로 통과방법에 따른 차량 당 $CO_2$ 배출량차이를 비교하였다. 둘째, 전체 대상구간에서 자유속도와 지정체 속도에 따른 차량 당 $CO_2$ 배출량차이를 비교하였다. 셋째, 구간별 차량당 $CO_2$ 배출량차이를 비교하였다. 차량 당 $CO_2$ 배출의 정량화를 위하여 속도에 따른 배출량 곡선을 사용하였다. 연구 결과는 첫째, 교차로에서 감가속 방법에 따라 최대 12%까지 차량 당 $CO_2$ 배출량의 차이가 나타났다. 둘째, 대상 구간 전체에서 지정체로 인해 30%이상 차량 당 $CO_2$를 배출하는 것으로 나타났다. 셋째, 구간별 비교 결과 교차로 특성 등에 따라 최대 차량 당 40%까지 차이가 나타났다. 본 연구를 통해 교차로 통과방법, 통행속도, 교차로 특성을 개선하면 차량 당 $CO_2$ 배출량을 감소할 수 있다는 추론이 가능하다.

• The Plant Pathology Journal
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• 제24권4호
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• pp.392-399
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• 2008

Detached chili pepper fruits were inoculated with the conidial suspension of Colletotrichum acutatum JC-24 simultaneously (simultaneous inoculation, SI) and at delayed time (delayed inoculation, DI) after wounding with (delayed wound inoculation, DWI) or without additional wounding (delayed non-wound inoculation, DNI) at the inoculation time. Disease severity was significantly lowered by DNI, compared to SI. By DNI, the disease reduction rates were proportional with the length of delayed time, and greater at the high temperature range (18, 23 and $28^{\circ}$) than at the low temperature ($13^{\circ}$) tested. DWI was also effective in reducing the disease severity especially at 18oC; however, its effectiveness was lower than for DNI. In light microscopy, parenchyma cells at the wounding sites were modified structurally, initially forming new cell walls crossing cytoplasm, enlarged with multiple periclinal cell divisions, and finally layered like wound periderms. In DWI, the above structural modifications occurred, showing the restriction of the fungal invasion by the cell walls in enlarged modified cells, while no definite cellular modifications were found with proliferation of fungal hyphae in SI. Sclerenchyma-like cells with thickened cell walls were proliferated around the wounding sites, which were partially dissolved by DWI, probably leading to some disease development. All of these results suggest that the decline of the anthracnose disease in pepper fruit by the delayed inoculations may be derived from the structural modifications related to the healing processes of the previous wound inflicted on the tissues.

• Journal of Microbiology and Biotechnology
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• 제16권8호
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• pp.1262-1268
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• 2006

In the search for a novel cytotoxic substance from medicinal plants, HY53 ($C_{17}H_{32}O_2N_2$; molecular weight 296) was isolated from the leaves of Pata de Vaca (Bauhinia forficata). The growth of the HepG2 cells was inhibited in a dose-dependent manner when treated with 0.07 to 0.40 mM HY53 for 24 h (IC$_{50}$: 0.13 mM). Furthermore, nuclear DAPI staining revealed the typical nuclear features of apoptosis in the HepG2 cells exposed to 0.27 mM HY53, whereas a flow cytometric analysis of the HepG2 cells using propidium iodide showed that the apoptotic cell population increased gradually from 8% at 0 mM to 23% at 0.14 mM and 45% at 0.40 mM after being exposed to each concentration of HY53 for 24 h. Moreover, a TUNEL assay also exhibited the apoptotic induction of the HepG2 cells treated with HY53. To obtain further information on the HY53-induced apoptosis, the expression level of certain apoptosis-associated proteins was examined using a Western blot analysis. Treatment of the HepG2 cells with HY53 resulted in the activation of caspase-3, and subsequent proteolytic cleavage of poly(ADP-ribose) polymerase (PARP). Consequently, the results confirmed that the apoptosis in the HepG2 cells was induced by HY53 and the involvement of caspase-3-mediated PARP cleavage in the apoptotic process.

• Asian-Australasian Journal of Animal Sciences
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• 제19권5호
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• pp.756-762
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• 2006

The objective of this study was to define the effects of various cooking and re-heating methods (pan roasting, steaming, oven grilling and micro-waving) on the cholesterol and formation of cholesterol oxidation products in beef loin during storage at $4^{\circ}C$. Raw samples showed lower total cholesterol content than cooked products sampled during storage for 6 d. The following cholesterol oxidation products (COPs) were separated by gas chromatography: $7{\beta}$-hydroxy cholesterol, $20{\alpha}$-hydroxy cholesterol, 25-hydroxy cholesterol, cholestane-$3{\beta}$, $5{\alpha}$, $6{\beta}$ triol (triol), ${\alpha}$-epoxide and 7-ketocholesterol. Total amounts of COPs/cholesterol at 0 d were 0.74, 0.63, 0.76, 1.23 and 0.83% for the raw sample, pan roasting, steaming, oven grilling and micro waving methods, respectively. After 6 d storage almost of the samples had higher content of total COPs than at 0 and 3 d; the lowest (0.55%) COPs was found in the steaming cooking and re-heating method. The highest (5.96%) of COPs was found in the pan roasting cooking and re-heating method after 6 d storage. In conclusion, the concentration of total cholesterol and cholesterol oxidation of beef loin were increased as a consequence of cooking and re-heating methods. Steaming and micro-waving methods showed the lowest of cholesterol oxidation products under refrigerated storage for 6 d. However, each cooking and re-heating method had its own distinctive cooking effects.

• Clinical and Experimental Reproductive Medicine
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• 제16권2호
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• pp.131-138
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• 1989

The present study was designed to develop a new method for the determination of estrogen receptor in porcine uterus using frozen sections. Cryostat sections were incubated with $^3H$-estradiol($^3H$-$E_2$) in the presence or absence of diethylstilbestrol(DES) and the radioactivity of 3H-E2 bound to estrogen receptor(ER) was detected. The level of specific estrogen receptor was determined by Scatchard analysis. The highest ratio of specific binding against total binding was achieved in 3 sec. tions(5mm x 5mm) which was corresponded to lOO${\mu}$/ml protein concentration. Optimal binding was obtained during incubation with $^3H$-$E_2$ for 30 minutes at 23$^{\circ}C$ after treatment of sections with acetone for 20 seconds. Three time-washing of sections was proved to be appropriate for the removal of unbound 3H-E2. 200-fold molar excess of DES was substituted for the binding of $^3H$-$E_2$ to ER sufficiently(binding efficiency of 54.8%). ER was saturated with 4nM of $^3H$-$E_2$ and its dissociation constant was 0.1nM. ER assay using frozen sections(Histological radioreceptor assay, HRRA) was significantly correlated with radioreceptor assay for estradiol(RRA, 0.976 , p

• The International Journal of Costume Culture
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• 제3권3호
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• pp.201-211
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• 2000

The purpose of this study is to pinpoint currently arising issues concerning cyber fashion mall by analysing present status and contents of its web design, management and planning within the limits o business to customer (B2C) commerce, and to suggest a direction for building an ideal fashion mall on the internet. As for the study method, conceptual definitions were given based on previous studies. And a positive study was implemented, in which the cases of 23 chosen cyber fashion malls among 60 or so domestic and foreign malls selling fashion products were found by internet search engines and analysed. Results of the case analysis of cyber fashion malls are as follows : 1) cybermall must provide customers with an integrated service as well as e-commerce. 2) various products assortment and price differentiation must be developed, 3) the techniques of graphics, coloring and texturing, and layout design must be adopted to process and express product information, 4) the legislative system is needed to deal with the security, and 5) design and management of customer oriented interface are needed to process and express product information matter of electronic payment and customer protection. Considering the issues in internet fashion cybermalls, are suggested the important factors that are necessary or web design, planning and management to build an ideal cyber fashion mall. These results will contribute to the development of fashion e-commerce.

• Asian-Australasian Journal of Animal Sciences
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• 제8권6호
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• pp.617-625
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• 1995

Distribution of wholesale carcass cuts and tissues was studied in Omani Dhofari bulls and steers raised under intensive management and slaughtered over a range of 110 to 210 kg body weight. The fore quarter of Dhofari cattle carcasses was heavier than the hind quarter with the chuck being the heaviest cut in the half carcass followed by the round whereas the flank was the lightest cut. Proportions of the fore quarter and its cuts increased whereas that of the hind quarter and its cuts decreased with increasing carcass weight. The fore quarter contained higher proportions of carcass tissues especially intermuscular fat than the hind quarter. The chuck and round contained the highest proportions of lean and bone and the flank the least. There was a general trend of increasing proportions of fat and decreasing proportions of lean and bone in carcass cuts and fore and hind quarters with increasing slaughter weight and age. As % total body fat (TBF), total carcass fat (TCF) increased whereas total non-carcass fat (TNCF) decreased. The largest proportion of TBF was deposited in the intermuscular site. Among the TNCF depots, the kidney and omental contributed the highest proportions whereas the pelvic and channel were the lowest. Proportions of M. rhomboideus and M. splenius increased in the half carcass whereas that of M. semitendinosus decreased as the cattle increased in size. The axial skeleton contributed 47.4-51.1, the fore limb 21.6-22.6 and the hind limb 23.9-26.2% of the total carcass bone. Proportions of axial skeleton increased whereas that of fore and hind limbs decreased with increasing slaughter weight and age. There were no major effects of castration on the distribution of weight of carcass cuts or carcass tissues. Steers had higher total body fat at 160 kg body weight and higher proportions of mesenteric, scrotal, pelvic, kidney and total non-carcass fat at 210 kg weight than bulls. As % of total body fat, steers fad significantly higher kidney and total non-carcass fat. There was little effects of castration on proportions of dimensions of individual muscles or bones.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2010년도 정기총회 및 춘계학술발표회
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• pp.18-18
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• 2010

Glucosinolates(GSLs) are major secondary products($\beta$-thioglucoside N-hydroxysulfates) containing sulfates that are found mainly in Cruciferae family such as cabbage, broccoli, radish, turnip, kale, mustard and rapeseed as the important crops in agronomic and economic aspects. Especially, isothiocyanates(ITCs) have been shown to inhibit carcinogenesis with regulation cancer cell development followed by regulating target enzymes, inducing cell cycle arrest and apoptosis against various human cancer cell lines. Total desulfo(DS)-GSLs of nine type in 210 Korean leaf mustard accessions were isolated and confirmed using electrospray ionization mass spectrometric(ESI-MS/MS) method and DS-GSLs powerful library maked from several reference data. The isolated individual DS-GSLs were identified by removed $\beta$-D-glucopyranose residue ($C_6H_{11}O_5$, MW 163) from MS/MS data. Among them sinigrin(41.7%), glucoiberverin(21.7%) and gluconasturtiin(12.6%) were major components, Especially, despite gluconapin was minor component, accession K046197-1 and K046197-2 showed higher content of 4.11 and 3.31 mg/g(DW), respectively. The total GSLs contents in 210 accessions were ranged from 5.3 to 23.2 mg/g(DW) with a mean value of 13.0 mg/g(DW). As a result of principal component analysis(PCA), the individual GSLs loading plots were composed of three groups and components belonged to each group showed correlationship in quantitative pattern.