• 대한수학회보
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• 제58권1호
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• pp.21-30
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• 2021

In this paper, we prove some rigidity results about embedded minimal hypersurface M ⊂ ℝn+1 with compact ∂M that has one end which is regular at infinity. We first show that if M ⊂ ℝn+1 meets a hyperplane in a constant angle ≥ ��/2, then M is part of an n-dimensional catenoid. We show that if M meets a sphere in a constant angle and ∂M lies in a hemisphere determined by the hyperplane through the center of the sphere and perpendicular to the limit normal vector nM of the end, then M is part of either a hyperplane or an n-dimensional catenoid. We also show that if M is tangent to a C2 convex hypersurface S, which is symmetric about a hyperplane P and nM is parallel to P, then M is also symmetric about P. In special, if S is rotationally symmetric about the xn+1-axis and nM = en+1, then M is also rotationally symmetric about the xn+1-axis.

• Annals of Clinical Neurophysiology
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• 제25권2호
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• pp.84-92
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• 2023

Background: Clinical spectrum of immunoglobulin M (IgM) monoclonal gammopathy varies from IgM monoclonal gammopathy of unknown significance (IgM-MGUS) to hematological malignancies. We evaluated the clinical features, electrophysiological characteristics, and prognosis of patients with peripheral neuropathy associated with IgM monoclonal gammopathy (PN-IgM MG). Methods: We retrospectively evaluated 25 patients with PN-IgM MG. Peripheral neuropathy was classified as axonal, demyelinating, or undetermined, based on electrophysiological studies. We classified the enrolled patients into the IgM-MGUS and malignancy groups, and compared the clinical and electrophysiological features between the groups. Results: Fifteen patients had IgM-MGUS and 10 had hematologic malignancies (Waldenström's macroglobulinemia: two and B-cell non-Hodgkin's lymphoma: eight). In the electrophysiological evaluation, the nerve conduction study (NCS) criteria for demyelination were met in 86.7% of the IgM-MGUS group and 10.0% of the malignancy group. In particular, the distal latencies of the motor NCS in the IgM-MGUS group were significantly prolonged compared to those in the malignancy group (median, 9.1 ± 5.1 [IgM-MGUS], 4.2 ± 1.3 [malignancy], p = 0.003; ulnar, 5.4 ± 1.9 [IgM-MGUS], 2.9 ± 0.9 [malignancy], p = 0.001; fibular, 9.3 ± 5.1 [IgM-MGUS], 3.8 ± 0.3 [malignancy], p = 0.01; P-posterior tibial, 8.3 ± 5.4 [IgM-MGUS], 4.4 ± 1.0 [malignancy], p = 0.04). Overall treatment responses were significantly worse in the malignancy group than in the IgM-MGUS group (p = 0.004), and the modified Rankin Scale score at the last visit was higher in the malignancy group than in the IgM-MGUS group (2.0 ± 1.1 [IgM-MGUS], 4.2 ± 1.7 [malignancy], p = 0.001), although there was no significant difference at the initial assessment. Conclusions: The risk of hematological malignancy should be carefully assessed in patients with PN-IgM MG without electrophysiological demyelination features.

• BMB Reports
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• 제32권2호
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• pp.127-132
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• 1999

The NAD(P)H-quinone oxidoreductase (EC 1. 6. 99. 2) was purified from S. cerevisiae. The native molecular weight of the enzyme is approximately 111 kDa and is composed of five identical subunits with molecular weights of 22 kDa each. The optimum pH of the enzyme is pH 6.0 with 1,4-benzoquinone as a substrate. The apparent $k_m$ for 1,4-benzoquinone and 1,4- naphthoquinone are 1.3 mM and $14.3\;{\mu}M$, respectively. Its activity is greatly inhibited by $Cu^{2+}$ and $Hg^{2+}$ ions, nitrofurantoin, dicumarol, and Cibacron blue 3GA. The purified NAD(P)H-quinone oxidoreductase was found capable of reducing aromatic nitroso compounds as well as a variety of quinones, and can utilize either NADH or NADPH as a source of reducing equivalents. The nitroso reductase activity of the purified NAD(P)H-quinone oxidoreductase is strongly inhibited by dicumarol.

• 미생물학회지
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• 제15권3호
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• pp.123-130
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• 1977

In previous paper, it was reported that antibiotic substance such as tetracycline and streptomycin were produced by S'. albus subsp. and S'. globosus. And increase of mycelial growth of two strains, antibiotic production, and changes of pH range are extended to approximately 110-130 hrs in fermenting medium, there-after they decreased with culture period exception of pH range. Two Streptomyces spp. required commonly 4-5% starch as carbon sources and 1.5-2.0% soybean meal as nitrogen sources. However, 0.005-0.01M potassium phosphate dibasic, calcium carbonate (6mg/ml in S.albus subsp. and 2mg/ml in S. globosus), 0.01-0.03M, magnesium sulgate and 0.01M ferric chloride showed as optimal concentration for the growth of 2 strains. Mineral compoments such as zinc, manganese, cobalt, sodium and copper at the level of 10/sup -4/ -10/sup -6/M were observed. Especially, zinc ion showed toxicity to the growth of 2 strains at 0.005M. In relation with pH, there is a little difference in mycelial growth with cultural initial pH.

• 동물자원연구
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• 제29권4호
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• pp.166-171
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• 2018

본 연구는 돼지의 정자와 난소내 과립막세포에서 bisphenol S(BPS)가 생존성과 활성산소 생산에 미치는 영향을 알아보고자 연구하였다. 돼지정액은 0, $5{\mu}M$ BPS를 처리하여 3, 6시간동안 배양하였다. 정자의 생존성은 SYBR14/PI를 이중 염색하여 분석하였으며, 활성산소의 생산을 측정하였다. 또한, BPS(0, 5, 10, $20{\mu}M$)를 과립막세포에 처리하여 24, 48, 72시간동안 처리하였다. 처리 후, 세포의 생존율과 활성산소 생산(단, $5{\mu}M$ BPS)을 측정하였다. 그 결과, 돼지에서 정자의 생존율은 BPS에 의해 감소하였고, 활성산소의 생산은 모든 처리시간에서 증가하였다(p<0.05). 또한 과립막세포의 생존은 BPS에 의해 억제되었고, 활성산소는 유의적으로 증가하였다(p<0.05). 이상의 결과를 토대로, BPS의 노출은 정자의 활성과 번식과 관련된 세포에 나쁜 영향을 미칠 것이다.

• 대한수학회보
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• 제46권5호
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• pp.931-940
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• 2009

Given a system of smooth 1-forms $\theta$ = ($\theta^1$,...,$\theta^s$) on a smooth manifold $M^m$, we give a necessary and sufficient condition for M to be foliated by integral manifolds of dimension n, n $\leq$ p := m - s, and construct an integrable supersystem ($\theta,\eta$) by finding additional 1-forms $\eta$ = ($\eta^1$,...,$\eta^{p-n}$). We also give a necessary and sufficient condition for M to be foliated by reduced submanifolds of dimension n, n $\geq$ p, and construct an integrable subsystem ($d\rho^1$,...,$d\rho^{m-n}$) by finding a system of first integrals $\rho=(\rho^1$,...,$\rho^{m-n})$. The special case n = p is the Frobenius theorem on involutivity.

• Bulletin of the Korean Chemical Society
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• 제14권6호
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• pp.678-681
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• 1993

The new ternary phase $UP_2S_6$ has been prepared and structurally characterized. The compound is isostructural with $ZrP_2S_6$ and $ThP_2S_6$ but is different from $TiP_2S_6$. The structure has been determined by a single crystal X-ray diffraction technique. $UP_2S_6$ crystallizes in the the tetragonal system $({C^2}_{4h}-P4_2/m,\;a=6.797(7)\;{\AA},\;c=9.738(12)\;{\AA})$ with two formula units in the unit cell. The structure can be described in terms of $U^{4+}$ and ${P_2S_6}^{4-}$ ions. This hexathiohypodiphosphate anion $({P_2S_6}^{4-})$ has ideally staggered conformation. The $U^{4+}$ cation is coordinated by 8 sulfur atoms in a slightly distorted dodecahedral geometry (42m). The distribution of sulfur atoms is very well optimized for this geometry.

• 한국수산과학회지
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• 제34권2호
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• pp.156-159
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• 2001

본 연구는 반 연속 rotifer 고밀도 배양에 있어서 배양 수온, 초기 접종밀도 및 pH조절에 따른 담수산 rotifer, Brachionus calyciflorus와 해수산 rotifer, B. rotundifomis의 생산성을 비교 조사하였다. 실험은 6L 배양용기 (배양수 5L)에 담수산 농축 Chlorella를 먹이로 공급하였다. pH를 조절하지 않은 반 연속 rotifer 고밀도 배양에서 B. calyciflorus와 B. rotundifomis의 일일 평균 생산량은 수온이 높을수록 높게 나타났고 수온 $32^{\circ}C$ 실험구에서 B. calyciflorus가 일일 $44\times10^6$개체로 가장 높은 생산량을 보였다 (P<0.05). 또한 이들의 생산 기간은 B. calyciflorus가 B. rotundiformis보다 상당히 길게 나타났다. 한편 pH를 7로 조절하면서 B. calyciflorus와 B. rotundiformis의 초기 접종밀도를 5,000개체/mL로 할 경우, 생산 기간이 각각 12일과 11일로 초기 접종밀도 10,000개체/mL의 2일과 8일 보다 길게 나타났고, 생산률도 $130\%$로 높게 나타났다. 본 연구를 종합하여 볼 때, B. calyciflorus와 B. rotundiformis의 반 연속 고밀도 배양에 있어서 생산 효율과 먹이 비용을 고려할 때 $32^{\circ}C$에서 pH 7 조절 하에 초기 접종밀도를 5,000개체/mL로 하는 것이 가장 효과적이고 안정적인 반 연속 rotifer 고밀도 배양이 될 것으로 판단된다.

• 대한수학회보
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• 제32권1호
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• pp.103-113
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• 1995

Let $S^{n+p}$(c) be the (n + p)-dimensional Euclidean sphere of constant curva ture c and let M be an n-dimensional compact minimal submanifold isometric ally immersed in $S^{n+p}$(c). Let $A_\xi$ be the second fundamental form of M in the direction of a normal $\xi$ and T the tensor defined by $T(\xi, \eta) = traceA_\xi A_\eta$.

• Childhood Kidney Diseases
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• 제6권2호
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• pp.188-197
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• 2002

목적 : 최근 우리 나라의 음식물에는 칼슘을 보강한 제품이 널리 유통되고 있고, 사람들의 칼슘섭취에 대한 인식도 달라지고 있다. 최근 본원에서는 혈뇨를 주소로 내원하여 검사를 시행한 환아에게서 고칼슘뇨증 소견에 합당한 경우가 늘어나 이에 본원을 방문한 소아를 대상으로 최근 10년간의 혈중 칼슘치와 그에 관계된 혈중 ALP, 크레아티닌, 나트륨, 칼륨, 혈중 중탄산염과 요중 pH와의 상관관계 및 변화 양상을 비교 분석해 보았다. 대상 및 방법 : 1991년, 1992년과 2000년, 2001년 본원에서 편도선 및 아데노이드 제거수술과 고환 고정술 및 탈장 봉합술을 시행한 환아를 대상으로, 혈중 칼슘, ALP, 크레아티닌, 나트륨, 칼륨, 중탄산염과 요중 pH 값을 조사하였다. 연도군 별로는 1991년, 1992년에 355명의 환아와 2000년, 2001년에 488명의 환아를 대상으로 하여 각 연령군 간에 t-test를 통해 분석하였다. 결과 : 2001년도군에서는 칼슘, ALP, 크레아티닌, 나트륨, 칼륨, 소변 pH의 값이 각각 $9.91{\pm}0.50\;mg/dL,\;248.58{\pm}94.98\;U/L,\;0.61{\pm}0.14\;mg/dL,\;138.64{\pm}2.22\;mM/L,\;4.35{\pm}0.40\;mM/L,\;6.18{\pm}0.86$으로 1991년도군의 각 각의 값인 $9.13{\pm}0.68;mg/dL,\;198.26{\pm}79.34\;U/L,\;0.433{\pm}0.18\;mg/dL,\;137.86{\pm}2.67\;mM/L,\;4.22{\pm}0.36\;mM/L,\;5.83{\pm}0.95$에 비해 모두 P-value 0.05이하의 유의한 증가를 보였고, 혈중 중탄산염은 2001년도군에서는 $23.64{\pm}2.57\;mM/L$로 1991년도군의 $24.60{\pm}2.23\;mM/L$에 비해 P-value 0.000으로 통계적으로 유의한 감소를 보였다. 각 연령별, 성별 비교에서도 같은 양상을 보인다. 결론 : 최근 10년간의 강원도 소아의 혈중 칼슘치는 의미 있게 증가하였다. 이는 칼슘의 경구 섭취량의 증가에 기인한 것이 큰 영향을 미친다고 사료되며 이에 대한 재인식과 교육이 필요하다고 생각한다.