• 약학회지
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• 제39권3호
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• pp.276-282
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• 1995

Compared to the first and second-generation cephalosporins, the third-generation cephalosporins are remarkably stable against hydrolysis by the $\beta$-lactamases produced by aerobic gram-negative bacilli, such as Enterobacteriaceae. Among these bacteria, the most prevalent plasmid-encoded $\beta$-lactamase is TEM-1 $\beta$-lactamase belonging to class A or group 2b. This enzyme is produced constitutively and is principally active against peniciflins and old cephalosporins rather than third-generafion cephalosporins, carbapenems and mmobactams. However, new TEM type $\beta$-lactamases including TEM-9 and TEM-12 evolved through point mutations in a gene encoding $\beta$-lactamase have been discovered from patients during chemotherapy. These $\beta$-lactamases are known to be capable of hydrolyzing most of the third-generatim cephalosporins. To study the prevalence of $\beta$-lactamases from clinical isolates collected in Korea. the minimal inhibitory concentratims(MICs) of several third-generation cephalosporins against 628 clinical isolates were determined by agar dilution methods, and $\beta$-lactamas-producing bacteria were isolated by use of cefinase disc. By polymerase chain reaction (PCR) method, clinical isolates harboring a gene for TEM type $\beta$-lactamase were identified among the $\beta$-lactamase producing strains. Twentiy three percent of the clinical isolates was resistant to the thirdgeneration cephalosporins, and more than 90% of resistant cells produced various $\beta$-lactamases. TFM type $\beta$-lactamases were dominant in gram-negative bacilli, such as Escherichia coli, Klebsiella pneumoniae, Enterobacter species. These results suggest the necessity of the development of new cephalosporins which are stable against $\beta$-lactamases like TEM.

• Mycobiology
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• 제38권2호
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• pp.144-148
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• 2010

$\beta$-Glucans have been known to exhibit antitumor activities by potentiating host immunity by an unknown mechanism. The C-type lectin dectin-1, a $\beta$-glucan receptor, is found on the macrophage and can recognize various $\beta$-glucans. Previously, we demonstrated the presence of $\beta$-glucan receptor, dectin-1, on the Raw 264.7 cells as well as on murine mucosal organs, such as the thymus, the lung, and the spleen. In order to investigate immunopotentiation of innate immunity by $\beta$-glucan, we stimulated a murine macrophage Raw 264.7 cell line with $\beta$-glucans from Pleurotus ostreatus, Saccharomyces cerevisiae, and Laminaria digitata. Then, we analyzed cytokines such as tumor necrosis factor (TNF)-$\alpha$ and interleukin (IL)-6 by reverse transcription-polymerase chain reaction (RT-PCR). In addition we analyzed gene expression patterns in $\beta$-glucan-treated Raw 264.7 cells by applying total mRNA to cDNA microarray to investigate the expression of 7,000 known genes. When stimulated with $\beta$-glucans, the macrophage cells increased TNF-$\alpha$ expression. When co-stimulation of the cells with $\beta$-glucan and lipopolysaccharide (LPS), a synergy effect was observed by increased TNF-$\alpha$ expression. In IL-6 expression, any of the $\beta$-glucans tested could not induce IL-6 expression by itself. However, when co-stimulation occurred with $\beta$-glucan and LPS, the cells showed strong synergistic effects by increased IL-6 expression. Chip analysis showed that $\beta$-glucan of P. ostreatus increased gene expressions of immunomodulating gene families such as kinases, lectin associated genes and TNF-related genes in the macrophage cell line. Induction of TNF receptor expression by FACS analysis was synergized only when co-stimulated with $\beta$-glucan and LPS, not with $\beta$-glucan alone. From these data, $\beta$-glucan increased expressions of immunomodulating genes and showed synergistic effect with LPS.

• 한국작물학회지
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• 제41권spc1호
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• pp.10-24
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• 1996

[ ($1{\to}3$) ], ($1{\to}4$)-${\beta}$-D-glucans(${\beta}-glucans$) are a major component of the cell walls of grasses as a component of the cereal endosperm and aleurone cell walls. Although ${\beta}-glucans$ exist in all cereals, their concentration is highest in oats and barley. Genetic and environmental differences are found in total ${\beta}-glucan$ content. Both oats and barley ${\beta}-glucans$ have cholesterol-lowering effects. This suggests possible use as food additives. Structural characterization of ${\beta}-glucan$ is important because structure can influence physical and physiological properties. In this review, ${\beta}-glucans$ of barley and oats are discussed in details including structure, chemical and physical properties, and nutritional implications. The use of barley and oat products as well as ${\beta}-glucan$ as a food additive continues to increase. This can provide an additional market for barley and oats, thus increasing the value of the crops.

• Food Science and Biotechnology
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• 제16권3호
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• pp.485-488
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• 2007

Plentiful amount of spent yeast has been produced as a by-product from breweries. ${\beta}-Glucan$ was prepared from the spent brewer's yeast in a crude form with hot water extraction and subsequent enzymatic treatment. The crude ${\beta}-glucan$ preparation consisted of mainly glucan (53% of total wt), containing approximately 35% ${\beta}-glucan$ content of total weight. The effects of crude ${\beta}-glucan$ substitution (1-9%) on pasting properties of wheat flour and starch were determined using a Rapid Visco-Analyzer (RVA). Incorporation of yeast ${\beta}-glucan$ into wheat flour and starch significantly decreased peak and [mal viscosities, but slightly increased setback viscosity. The setback viscosity was considerably higher in starch/${\beta}-glucan$ suspension than in flour/${\beta}-glucan$ suspension. It was suggested that preparation of yeast ${\beta}-glucan$ into aqueous dispersion might affect pasting behaviors of wheat flour and starch.

• Biomolecules & Therapeutics
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• 제21권5호
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• pp.323-331
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• 2013

TGF-${\beta}$ pathway is being extensively evaluated as a potential therapeutic target. The transforming growth factor-${\beta}$ (TGF-${\beta}$) signaling pathway has the dual role in both tumor suppression and tumor promotion. To design cancer therapeutics successfully, it is important to understand TGF-${\beta}$ related functional contexts. This review discusses the molecular mechanism of the TGF-${\beta}$ pathway and describes the different ways of tumor suppression and promotion by TGF-${\beta}$. In the last part of the review, the data on targeting TGF-${\beta}$ pathway for cancer treatment is assessed. The TGF-${\beta}$ inhibitors in pre-clinical studies, and Phase I and II clinical trials are updated.

• 한국미생물·생명공학회지
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• 제18권6호
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• pp.566-570
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• 1990

Lactobacillus sporogenes에서 Beta-glactosidase의 생합성은 isopropyl-Beta-galactopyransoide(IPTG)나 galactose에 의해 효과적으로 유도되었으며 배양초기에는 lactose에 의해서도 훨씬 낮은 정도로 유도되었다. Glucose는 inducer exclusion이나 transient repression이 아니 catabolite repression에 의해 Beta-galactosidase의 합성을 억제시킴을 알 수 있었다. 또한, glucose에 의한 Beta-galactosidase의 catabolite repression은 cAMP나 cGMP에 의해 전혀 완하되지 않았다.

• 대한수학회보
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• 제46권4호
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• pp.645-656
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• 2009

J. Wang [21] proposed a problem: whether the Hyers-Ulam-Rassias stability of Jensen's equation for the case p, q, r, s $\in$ ($\beta$, $\frac{1}{\beta}$) \ {1} holds or not under the assumption that G and E are $\beta$-homogeneous Fspace (0 < $\beta\;\leq$ 1). The main purpose of this paper is to give an answer to Wang's problem. Furthermore, we proved that the stability property of Jensen's equation is not true as long as p or q is equal to $\beta$, $\frac{1}{\beta}$, or $\frac{\beta_2}{\beta_1}$ (0 < $\beta_1,\beta_2\leq$ 1).

• 대한수학회논문집
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• 제32권3호
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• pp.535-542
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• 2017

Let R be an associative ring and ${\alpha},{\beta}:R{\rightarrow}R$ ring homomorphisms. An additive mapping $d:R{\rightarrow}R$ is called an (${\alpha},{\beta}$)-derivation of R if $d(xy)=d(x){\alpha}(y)+{\beta}(x)d(y)$ is fulfilled for any $x,y{\in}R$, and an additive mapping $D:R{\rightarrow}R$ is called a generalized (${\alpha},{\beta}$)-derivation of R associated with an (${\alpha},{\beta}$)-derivation d if $D(xy)=D(x){\alpha}(y)+{\beta}(x)d(y)$ is fulfilled for all $x,y{\in}R$. In this note, we intend to generalize a theorem of Vukman [5], and a theorem of Daif and El-Sayiad [2].

• 가정과삶의질연구
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• 제13권2호
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• pp.68-77
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• 1995

본 연구는 급속한 산업화와 현대화 과정에서 파생괸 과소비 호화혼수, 재벌의 변칙 적인 부의 세습, 상류층내의 배타적인 결혼 지나친 교육열, 환경오염등과 같은 다양한 가족 이기주의 현상의 심각성을 재인식하고 이에 영향을 미치는 요인을 살펴봄으로써 가족이기주 의의 예방을 개선을 도모해 나갈 기본자료를 마련하는데 목적을 두고 있다 서울시에 거주하 는 기혼남녀 333명을 대상으로 가족이기주의 행동의 실태와 이에대한 사회인구학적 변인과 가족주의 가치관의 영향을 살펴본 결과 가정내에서의 가족이기주의 행동에 영향을 미치는 변인은 성별($\beta=.238$), 교육수준($\beta=.237$), 소득($\beta=.188$), 가족우선성의식($\beta=.156$), 형제자매 및 친척간 사회경제적 연대의식($\beta=-.155$)이었고, 교육에서의 가족이기주의 행동에 영향을 미치는 변인은 소득($\beta=.233$), 성별($\beta=.200$), 연령($\beta=.176$), 교육수준($\beta=.156$)이었으며, 환경에서의 가족이기주의 행동에 영향을 미치는 변인은 소득($\beta=.263$)인 것으로 나타났다.

• 생약학회지
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• 제23권1호
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• pp.14-19
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• 1992

A mixture of acylglucosyl sterols together with ${\beta}-sitosterol$, ${\beta}-sitosterol\;3{\beta}-O-glucoside$ and fatty acids was isolated from the roots of Caragana chamlagu as their acetate forms and the structure elucidated by chemical and spectroscopic means. The major acylglucosyl sterol was ${\beta}-sitosteryl\;3-O-[6'-O-oleoyl]-{\beta}-D-glucopyranoside$ while the minor components were $6'-O-palmitoyl-\;and\;6'-O-stearoyl-{\beta}-D-glucosyl$ sitosterol congeners. The isolation and structure elucidation of these acylglucosyl sterols are reported for the first time from the genus Caragana.