• 제목/요약/키워드: NE

검색결과 1,855건 처리시간 0.031초

Characterization of Norepinephrine Release in Rat Posterior Hypothalamus Using in vivo Brain Microdialysis

  • Sung, Ki-Wug;Kim, Seong-Yun;Kim, Ok-Nyu;Lee, Sang-Bok
    • The Korean Journal of Physiology and Pharmacology
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    • 제6권1호
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    • pp.9-14
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    • 2002
  • In the present study, we used the microdialysis technique combined with high performance liquid chromatography (HPLC) and electrochemical detection to measure the extracellular levels of norepinephrine (NE) in the posterior hypothalamus in vivo, and to examine the effects of various drugs, affecting central noradrenergic transmission, on the extracellular concentration of NE in the posterior hypothalamus. Microdialysis probes were implanted stereotaxically into the posterior hypothalamus (coordinates: posterior 4.3 mm, lateral 0.5 mm, ventral 8 mm, relative to bregma and the brain surface, respectively) of rats, and dialysate collection began 2 hr after the implantation. The baseline level of monoamines in the dialysates were determined to be: NE $0.17{\pm}0.01,$ 3,4-dihydroxyphenylacetic acid (DOPAC) $0.94{\pm}0.07,$ homovanillic acid (HVA) $0.57{\pm}0.05$ pmol/sample (n=8). When the posterior hypothalamus was perfused with 90 mM potassium, maximum 555% increase of NE output was observed. Concomitantly, this treatment significantly decreased the output of DOPAC and HVA by 35% and 28%, respectively. Local application of imipramine $(50\;{\mu}M)$ enhanced the level of NE in the posterior hypothalamus (maximum 200%) compared to preperfusion control values. But, DOPAC and HVA outputs remained unchanged. Pargyline, an irreversible monoamine oxidase inhibitor, i.p. administered at a dose of 75 mg/kg, increased NE output (maximum 165%), while decreased DOPAC and HVA outputs (maximum 13 and 12%, respectively). These results indicate that NE in dialysate from the rat posterior hypothalamus were neuronal origin, and that manipulations which profoundly affected the levels of extracellular neurotransmitter had also effects on metabolite levels.

교감신경절제 받은 신경병증성 통증 쥐 모델에서 Norepinephrine에 의해 유도된 기계적 이질통의 Rekindling의 기전 (Norepinephrine-Induced Rekindling of Mechanical Allodynia in Sympathectomized Neuropathic Rat)

  • 문동언
    • The Korean Journal of Pain
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    • 제9권2호
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    • pp.318-325
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    • 1996
  • Background: Sympathectomy relieves pain in sympathectically maintained pain, and subcutaneous injection of norepinephrine(NE) can rekindle mechanical allodynia. However, the mechanism of rekindling is not clear. The purpose of this study is to investigate which subtype of $\alpha$-adrenoceptor is involved in NE-induced rekindling of mechanical allodynia in sympathectomized neuropathic rats. Methods: Neuropathic injury was produced by tightly ligating the left L5 and L6 spinal nerves of 36 male Sprague-Dawley rats and bilateral lumbar sympathectomy was done at two weeks postoperatively. Starting at 7 days after sympathectomy, rekindling of mechanical allodynia was induced by NE and clonidine injected into the left paw, which was reversed by pretreatment of phentolamine and idazoxan. Mechanical allocynia was quantified by measuring the frequency of foot lifts to two von Frey filaments applied to the paw. Results: All tested rats displayed well-developed signs of mechanical allodynia at the left paw that were abolished by a bilateral lumbar sympathectomy. Subcutaneous (s.c.) injection of NE (0.05 ${\mu}g$) into the affected paw of sympathectomized neuropathic rats rekindled previous mechanical allodynia. These effects could be mimicked by an ${\alpha}_2$-receptor agonist clonidine, but not by an ${\alpha}_1$-receptor agonist phenylephrine. The NE-induced rekindling of mechanical allodynia was significantly reduced by prior s.c. injection of a mixed $\alpha$-receptor antagonist phentolamine (20${\mu}g$) and ${\alpha}_2$-receptor antagonist idazoxan(20${\mu}g$), but not by a ${\alpha}_1$-receptor antagonist terazosin (20${\mu}g$). The pretreatment of idazoxan produced dose-related inhibition of NE-induced rekindling of mechanical allodynia. The rekindling induced by ${\alpha}_2$-receptor agonist clonidine (5${\mu}g$) was also reversed by prior s.c. injection of ${\alpha}_2$-receptor antagonist idazoxan (20${\mu}g$). Conclusion: Subcutaneous injection of NE into the paw of sympathectomized neuropathic rats rekindles mechanical allodynia, which is reversed by an ${\alpha}_2$-, but not by an ${\alpha}_1$-receptor antagonist. Therefore, rekindling of mechanical allodynia in sympathectomized neuropathic rats is mediated by ${\alpha}_2$-adrenoceptor.

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Influence of gas mixture He-Ne-Xe on the vacuum ultraviolet intensity in ac-PDPs.

  • Yoo, N.L.;Jung, K.B.;Lee, J.H.;Lee, S.B.;Han, Y.K.;Jeong, S.H.;Lee, H.J.;Son, C.G.;Lim, J.E.;Oh, P.Y.;Moon, M.W.;Jeoung, J.M.;Ko, B.D.;Cho, G.S.;Uhm, H.S.;Choi, E.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1221-1224
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    • 2005
  • The improvement of luminance and luminous efficiency is the one of the most important parts in AC-PDPs. To achieve high luminance and luminous efficiency, high VUV emission efficiency is needed. We measured the emission spectra of the vacuum ultraviolet(VUV) rays in surface discharge AC-PDP with ternary gas mixture of He-Ne-Xe. The influence of He-Ne-Xe gas-mixture ratio on excited $Xe^{\ast}$ resonant atoms and $Xe_2\;^{\ast}$ dimers has been investigated. It is found that luminous efficiency of ternary gas mixture, He-Ne-Xe, is shown to be much higher than that of binary gas mixture of Ne-Xe. For improving discharge luminous efficiency, we have studied VUV emission characteristics of ternary gas mixture, He(50%)-Ne-Xe and He(70%)-Ne-Xe with Xe concentration and filling gas pressure.

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Influence of Bromocriptine on Release of Norepinephrine and Epinephrine Evoked by Cholinergic Stimulation from the Rat Adrenal Medulla

  • Lee, Seung-Il;Kang, Moo-Jin;Lim, Dong-Yoon
    • Biomolecules & Therapeutics
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    • 제9권3호
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    • pp.201-208
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    • 2001
  • The present study was conducted to examine the effects of cholinergic stimulation and membrane depolarization on secretion of epinephrine (EP) and norepinephrine (NE) in the perfused model of the rat adrenal gland and to investigate the effect of bromocriptine on secretion of EP and NE evoked by these secreta-gogues. Acetylcholine (ACh, 5.32 mM), high $K^{+}$(56mM), 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP, 100 $\mu$M for 2 min), (3-(m-cholro-phenyl-carbamoyl-oxy)-2butynyl trimethyl ammonium chloride (McN-A-343, 100 $\mu$M for 2 min), cyclopiazonic acid (10 $\mu$M for 4 min) and methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl) -pyridine-5-carboxylate (Bay-K-8644, 10 $\mu$M for 4 min) evoked a 1.3~5.3-fold greater secretion of EP than NE in the perfused rat adrenal gland. The perfusion of bromocriptine (1-10 $\mu$M) into an adrenal vein for 20 min produced relatively dose-dependent inhibition in secretion of EP and NE evoked by ACh, high $K^{+}$, DMPP, and McN-A-343. Moreover, under the presence of bromocriptine (1~10 $\mu$M), releasing responses of EP and NE evoked by cyclopiazonic acid and Bay-K-8644 were also greatly reduced. Taken together, these results suggest that cholinergic stimulation and membrane depolarization enhance more release of EP than NE in the perfumed rat adrenal medulla, and that bromocriptine inhibits the release of EP and NE evoked by stimulation of cholinergic receptors as well as by membrane depolarization. It seems that this inhibitory effect of bromocriptine is associated with inhibition of calcium channels through activation of dopaminergic D2-receptors located in the rat adrenomedullary chromaffin cells.lls.

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N-Screen 환경 기반의 이러닝 시스템 설계 방안 (Design of e-Learning System in N-Screen Environment)

  • 신유진;서동수;홍승필
    • 인터넷정보학회논문지
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    • 제13권5호
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    • pp.45-53
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    • 2012
  • 지능형 모바일 및 가전기기의 등장은 다양한 멀티미디어 콘텐츠 뿐 아니라 교육용 콘텐츠의 이용량을 증대시켰다. 특히 이동성을 강조한 단말 기기인 스마트폰과 스마트패드의 보급 및 지능화된 스마트 TV의 등장은 다양한 단말 환경에서 편리하게 학습할 수 있는 환경을 제공하였고, 언제 어디서나 이용자가 교육용 콘텐츠를 이용할 수 있도록 했다. 그러나 현재 이용되고 있는 스마트 디바이스들은 단말 제조사 및 모바일 OS 공급자의 정책이 통일되지 않아 다양한 환경 내에서의 콘텐츠의 재사용이 어렵다. 이에 본 논문에서는 이러한 문제점을 해결하기 위해 NeS(N-Screen e-learning System)를 제안하고자 한다. NeS는 이용자 학습 관리, 교육 콘텐츠 관리의 교육 관련 시스템과 콘텐츠 변환과 양방향 처리로 이루어지는 N-Screen 대응 콘텐츠 전송 시스템으로 구성된다. NeS에서는 새로운 웹 표준으로 각광받고 있는 HTML 5 언어를 이용해 각종 기기간의 상호호환성을 보장한다. 본 논문에서 제시하는 NeS를 통해 사용자가 소유하고 있는 각종 기기 및 다양한 OS의 종류에 구애받지 않고 콘텐츠의 OSMU를 실현할 수 있고, 콘텐츠의 연속성을 보장하여 보다 편리하게 교육용 콘텐츠를 이용할 수 있다.

$BCl_3,\;BCl_3/Ar,\;BCl_3/Ne$ 유도결합 플라즈마에 의한 InGaP 건식 식각 비교 (Comparison of InGaef etching $BCl_3,\;BCl_3/Ar\;and\;BCl_3/Ne$ inductively coupled plasmas)

  • 백인규;임완태;이제원;조관식;전민현
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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    • pp.361-365
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    • 2003
  • Planar Inductively Coupled Plasma (PICP) etching of InGaP was performed in $BCl_3,\;BCl_3/Ar\;and\;BCl_3/Ne$ plasmas as a function of ICP source power ($0\;{\sim}\;500\;W$), RIE chuck power ($0\;{\sim}\;150\;W$), chamber pressure ($5\;{\sim}\;15\;mTorr$) and gas composition of $BCl_3/Ar\;and\;BCl_3/Ne$. Total gas flow was fixed at 20 sccm (standard cubic centimeter per minute). Increase of ICP source power and RIE chuck power raised etch rate of InGaP, while that of chamber pressure reduced etch rate. We also found that some addition of Ar and Ne in $BCl_3$ plasma improved etch rate of InGaP. InGaP etch rate was varied from $1580\;{\AA}/min$ with pure $BC_3\;to\;2800\;{\AA}/min$ and $4700\;{\AA}/min$ with 25 % Ar and Ne addition, respectively. Other process conditions were fixed at 300 W ICP source power, 100 W RIE chuck power and 7.5 mTorr chamber pressure. SEM (scanning electron microscopy) and AFM (atomic force microscopy) data showed vertical side wall and smooth surface of InGaP at the same condition. Proper addition of noble gases Ar and Ne (less than about 50 %) in $BCl_3$ inductively coupled plasma have resulted in not only increase of etch rate but also minimum preferential loss and smooth surface morphology by ion-assisted effect.

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위키피디아 기반 개체명 사전 반자동 구축 방법 (A Semi-automatic Construction method of a Named Entity Dictionary Based on Wikipedia)

  • 송영길;정석원;김학수
    • 정보과학회 논문지
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    • 제42권11호
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    • pp.1397-1403
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    • 2015
  • 개체명은 다양한 자연어처리 연구 및 서비스에 중요한 정보로 이용된다. 개체명 인식의 성능을 향상시키기 위한 여러 연구에서 개체명 사전을 이용한 자질이 개체명 인식 성능에 큰 영향을 준다는 것을 보이고 있다. 그러나 개체명 사전을 구축하는 것은 매우 시간 소모적이고, 인력 소모적인 작업이다. 이를 완화하기 위해서 본 논문에서는 개체명 사전을 반자동으로 구축하는 방법을 제안한다. 제안 시스템은 능동학습을 이용하여 위키피디아 분류정보로 구성된 가상 문서를 개체명 범주 당 하나씩 생성한다. 그리고 잘 알려진 정보검색 모델인 BM25를 이용하여 위키피디아 엔트리와 가상문서 사이의 유사도를 계산한다. 마지막으로 유사도를 바탕으로 각 위키피디아 엔트리를 개체명 범주로 분류한다. 서로 다른 3종류의 개체명 범주 집합에서 실험한 결과, 제안 시스템은 매크로 평균 F1-점수 0.9028, 마이크로 평균 F1-점수 0.9554이라는 높은 성능을 보였다.

BCI3Ne 혼합가스를 이용한 III-V 반도체의 고밀도 유도결합 플라즈마 식각 (High Density Inductively Coupled Plasma Etching of III-V Semiconductors in BCI3Ne Chemistry)

  • 백인규;임완태;이제원;조관식
    • 한국전기전자재료학회논문지
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    • 제16권12S호
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    • pp.1187-1194
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    • 2003
  • A BCl$_3$/Ne plasma chemistry was used to etch Ga-based (GaAs, AIGaAs, GaSb) and In-based (InGaP, InP, InAs and InGaAsP) compound semiconductors in a Planar Inductively Coupled Plasma (ICP) reactor. The addition of the Ne instead of Ar can minimize electrical and optical damage during dry etching of III-V semiconductors due to its light mass compared to that of Ar All of the materials exhibited a maximum etch rate at BCl$_3$ to Ne ratios of 0.25-0.5. Under all conditions, the Ga-based materials etched at significantly higher rates than the In-based materials, due to relatively high volatilities of their trichloride etch products (boiling point CaCl$_3$ : 201 $^{\circ}C$, AsCl$_3$ : 130 $^{\circ}C$, PCl$_3$: 76 $^{\circ}C$) compared to InCl$_3$ (boiling point : 600 $^{\circ}C$). We obtained low root-mean-square(RMS) roughness of the etched sulfate of both AIGaAs and GaAs, which is quite comparable to the unetched control samples. Excellent etch anisotropy ( > 85$^{\circ}$) of the GaAs and AIGaAs in our PICP BCl$_3$/Ne etching relies on some degree of sidewall passivation by redeposition of etch products and photoresist from the mask. However, the surfaces of In-based materials are somewhat degraded during the BCl$_3$/Ne etching due to the low volatility of InCl$_{x}$./.

개선된 네이버 임베딩에 의한 초해상도 기법 (Super Resolution Technique Through Improved Neighbor Embedding)

  • 엄경배
    • 디지털콘텐츠학회 논문지
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    • 제15권6호
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    • pp.737-743
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    • 2014
  • 단일 영상 초해상도 기법에는 보간 기반 방법과 표본 기반 방법 등이 있다. 보간 기반 방법들은 간결성에 강점을 가지고 있으나, 이들 방법들은 선지식을 이용할 수 없기 때문에 톱니 모양의 윤곽선을 가진 고해상도 영상을 생성하는 경향이 있다. 표본 기반 초해상도 기법에서는 최근방 기반 알고리즘들이 널리 이용되어 지고 있다. 그들 중, 네이버 임베딩은 지역적 선형 임베딩이라는 매니폴드 학습 방법의 개념과 같다. 그러나, 네이버 임베딩은 국부 학습 데이터 집합의 크기가 너무 작은데에 따른 빈약한 일반화 능력으로 인하여, 시각적으로나 정량적인 척도에 의해 취약한 성능을 보인다. 본 논문에서는 이와 같은 문제점을 해결하기 위해 개선된 네이버 임베딩 알고리즘을 제안하였다. 저해상도 입력 영상이 주어지면 고해상도 버전의 화소 값들은 개선된 네이버 임베딩 알고리즘에 의해 구해진다. 실험 결과 제안된 방법이 바이큐빅 보간법이나 네이버 임베딩에 비해 정량적인 척도 및 시각적으로도 우수한 결과를 보였다.

수종 한약재가 혈관에 미치는 영향 (Effects of Several Herbs on the Blood Vessel)

  • 한종현;최민호;남태선;유도곤
    • 대한한의학방제학회지
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    • 제7권1호
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    • pp.167-181
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    • 1999
  • Rhizoma Arisaematis, Lignum Akebiae, Rhizoma Zedoariae, Cortex Eucommiae, Folium Perillae, Radix Sophorae Subprostratae, Radixi, Radix Ledeboutriellae, Rhizoma Atractylodis, Herba Ephedrae, Radix Puerariae and Radi Aconitx Bupleuri have been used in Korea for many centuries as a treatment for various disease. The purpose of the present study is to determine the effect of several herbs on norepinephrine(NE) induced blood vessel contraction in rabbits and pigs. Rabbit(2 kg, male) were killed by $CO_2$ exposure and a segment (8-10mm) of each rabbit was cut into equal segments and mounted in a tissue bath. Contractile force was measured with force displacement transducers under 2-3 g loading tension. The dose of norepinephrine(NE) which evoked 50% of maximal response $(ED_{50})$ was obtained from cumulative dose response curves for NE $(10^{-6}{\sim}10^{-3}M)$. Contractions evoked by NE $(ED_{50})$ were inhibited significantly by Rhizoma Arisaematis, Lignum Akebiae, Rhizoma Zedoariae, Cortex Eucommiae, Folium Perillae, Radix Sophorae Subprostratae and Herba Ephedrae in abdominal aorta. Contractions evoked by NE $(ED_{50})$ were inhibited significantly be Lignum Akebiae, Rhizoma Zedoariae, Cortex Eucommiae, Herba Ephedrae, Radix Puerariae and Radix Bupleuri in femoral artery. Contractions evoked by NE $(ED_{50})$ were inhibited significantly by Radix Sophorae Subprostratae, Radix Aconiti and Herba Ephedrae in renal artery. These results indicate that each herb can relax NE induced contraction of rabbit and pig blood vessel selectively, and that this relaxation relates to Gui-Gyung(歸經).

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