• 제목/요약/키워드: Action pattern

검색결과 432건 처리시간 0.021초

노년기 배우자 사별 후 적응과정에서의 개인적 성장 (Personal Growth through Spousal Bereavement in Later Life)

  • 장수지
    • 한국사회복지학
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    • 제65권4호
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    • pp.165-193
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    • 2013
  • 본 연구의 목적은 노년기 배우자 사별 후의 성장과정을 살펴보고, 그에 대한 이론을 개발하는 것이다. 이를 위해 배우자와 사별한 노인 17명을 대상으로 질적 연구를 실시하였다. 심층면접 후 Strauss와 Corbin(1998)의 근거이론 방법을 적용하여 분석한 결과, 143개의 개념과 43개의 하위범주, 19개의 범주가 도출되었다. 배우자 사별 후 참여자들에게 나타난 중심현상은 '우울', '막막함', '생활상의 스트레스', '심리적 위축감', '회한', '홀가분함' 등의 심리적 반응이었다. 이러한 사별 직후의 심리적 손상 정도는 인과적 조건으로서 사별 전의 '부부관계', '개인의 독립적/의존적 성향', '사별에 대한 마음의 준비'에 따라 차이가 있었으며, 맥락적 조건에는 '친밀한 인간관계 구축에 대한 욕구', '독립성 유지에 대한 욕구'가 존재하였다. 현상을 극복하기 위한 작용/상호작용 전략은 '현실에 대한 직시'와 '새로운 삶을 위한 노력'이었으며, 이를 촉진, 제어하는 중재적 조건은 '사회적지지'와 '신앙생활'이었다. 나타난 결과, 즉 성장의 내용은 '삶의 의미 찾기', '자존감의 향상', '인간관계의 강화', '포용과 수용'이었다. 노년기 배우자 사별 후 성장의 과정은 시간 순에 따라 '슬픔과 절망단계', '끌어안고 나아가기 단계', '성장단계'로 이어졌다. 마지막으로 유형분석의 결과, 배우자 사별 후 성장과정은 '적극적 변화형', '발전적 적응형', '포용형', '답보형', '원망형'의 5가지로 분류되었다. 본 연구의 결과, 노년기 배우자 사별 후 성장은 노년기에 보편적으로 경험하게 되는 "발달적 위기 이후의 삶의 통합과정으로서, 배우자 사별 직후의 절망을 딛고 일어서 삶의 주체자로서 새로운 삶을 모색하고 더욱 강해진 자아를 발견해 나가며, 배우자를 포용해 나가는 과정"으로 개념화할 수 있다.

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좀개구리밥(Lemna gibba G3)의 개화에 미치는 Polyamine의 영향 (Effects of Polyamine on Flowering in Lemna gibba G3)

  • 김강창
    • Journal of Plant Biology
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    • 제35권4호
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    • pp.403-408
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    • 1992
  • 장일식물인 Lemna gibba G3의 개화유도과정에 있어서 polyamine의 관련성을 조사하였다. 이 식물의 개화는 연속광하에서 agmatine, putrescine, spermidine 및 spermine에 의해 촉진되었으며 이들의 체내 합성억제물질인 methylglyoxal-bis(guanylhydrazone)(MGBG)과 cyclohexylamine(CHA)에 의해서 억제되었다. Polyamine은 영양생장률을 거의 일정한 수준으로 유지하면서 개화를 촉진시켰으며, 억제물질에 의한 개화억제는 오히려 영양생장률의 증가를 수반하였다. 이러한 현상은 이 물질들의 개화촉진 또는 억제효과가 생장률의 일반적인 촉진 또는 억제효과에 의한 것이 아니라 선택적으로 개화과정에 작용한 결과일 것이라는 추측을 뒷받침해 준다. 배양액의 첨가된 spermidine 또는 spermine의 개화촉진 폭은 배양액에 이들의 억제물질의 함유여부와 관계없이 거의 일정한 수준으로 나타났다. 이렇듯, 외부에서 공급된 후 체내에 흡수된 spermidine과 spermine의 개화에 대한 기여도가 한정되어 있는 것으로 보아 L. gibba G3의 개화유도과정이 식물체내에서 합성되는 spermidine과 spermine에 크게 의존하고 있을 것으로 판단된다. 한편, 개화유도과정이 시작되어 점차적으로 증가한 체내의 spermidine 함량은 개화가 유도되지 않은 경우에 비하여 24시간만에 약 2배의 수준에 도달하였다. 이렇듯 체내의 spermidine량이 급격히 증가된 사실은 체내의 polyamine의 질적 및 양적 변화가 L. gibba G3의 개화유도초기과정에서 매우 중요한 역할을 하고 있을 것이라는 가정을 뒷받침하는 또 하나의 예비적 증거라 할 수 있다.

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Neuroendocrine Control of Gonadotropin Secretion during the Menstrual Cycle

  • Ryu, Kyung-Za
    • 대한약리학회지
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    • 제23권2호
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    • pp.57-75
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    • 1987
  • Two modalities of gonadotropin secretion, pulsatile gonadotropin and preovulatory gonadotropin surge, have been identified in the mammals. Pulsatile gonadotropin secretion is modulated by the pulsatile pattern of GnRH release and complex ovarian steroid feedback actions. The neural mechansim that regulates the pulsatile release of GnRH in the hypothalamus is called "GnRH pulse generator". Ovarian steroids, estradiol and progesterone, appear to exert thier feedback effects both directly on the pituitary to modulate gonadotropin release and on a hypothalamic site to modulate GnRH release; estradiol primarily affects the amplitude while progesterone decreases the frequency of the pulsatile GnRH. Steroid hormones are known to affect catecholamine transmission in brain. MBH-POA is richly innervated by NE systems and close apposition of NE terminals and GnRH cell bodies occurs in the MBH as well as in the POA. NE normally facilitates pulsatile LH release by acting through ${\alpha}-receptor$ mechanism. However, precise nature of facilitative role of NE transmission in maintaining pulsatile LH has not been clearly understood. Close apposition of DA and GnRH terminals in ME might permit DA to influence GnRH release. Action of DA transmission probably is mediated by axo-axonic contacts between GnRH and DA fibers in the ME. Dopamine transmission does not normally regulate pulsatile LH release, but under certain conditions, increased DA transmission inhibit LH pulse. Endogenous opioid acts to suppress the secretion of GnRH into hypophysial portal circulation, thereby inhibiting gonadotropin secretion. However, an interaction between endogenenous opioid peptides and gonadotropin release is a complex one which involves ovarian hormones as well. LH secretion appears to be most suppressed by endogenenous opioids during the luteal phase, at a time of elevated progesterone secretion. The arcuate nucleus contains not only cell bodies for GnRH and ${\beta}-endorphin$ but also a dense aborization of fibers suggesting that GnRH release is changed by the interactions between GnRH and ${\beta}-endorphin$ cell bodies within the arcuate nucleus. The frequency and amplitude of pulsatile LH release seem to be increased during the preovulatory gonadotropin surge. Estradiol exerts positive feedback action on the hypothalamo-pituitary axis to trigger preovulatory LH surge. GnRH is also crucial hormonal stimulus for preovulatory LH surge. It is unlikely, however, that increased secretion of GnRH during the preovulatory gonadotropin surge represents an obligatory neural signal for generation of the LH discharge in primates including human. Modulation of preovulatory LH surge by catecholamines has been studied almost exclusively in rats. NE and E may be involved in distinct way to accumulate GnRH in the MBH and its release into the hypophysial portal system during the critical period for LH surge on proestrus in rats. However, the mechanisms whereby augmented adrenergic transmission may facilitate the formation and accumulation of GnRH in the ME-ARC nerve terminals before the LH surge have not been clearly understood.

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The Role and Regulation of MCL-1 Proteins in Apoptosis Pathway

  • Bae, Jeehyeon
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2002년도 창립10주년기념 및 국립독성연구원 의약품동등성평가부서 신설기념 국재학술대회:생물학적 동등성과 의약품 개발 전략을 위한 국제심포지움
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    • pp.113-113
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    • 2002
  • Phylogenetically conserved Bcl-2 family proteins play a pivotal role in the regulation of apoptosis from virus to human. Members of the Bcl-2 family consist of antiapoptotic proteins such as Bcl-2, Bcl-xL, and Bcl-w, and proapoptotic proteins such as BAD, Bax, BOD, and Bok. It has been proposed that anti- and proapoptotic Bcl-2 proteins regulate cell death by binding to each other and forming heterodimers. A delicate balance between anti- and proapoptotic Bcl-2 family members exists in each cell and the relative concentration of these two groups of proteins determines whether the cell survives or undergoes apoptosis. Mcl-1 (Myeloid cell :leukemia-1) is a member of the Bcl-2 family proteins and was originally cloned as a differentiation-induced early gene that was activated in the human myeloblastic leukemia cell line, ML-1 . Mcl-1 is expressed in a wide variety of tissues and cells including neoplastic ones. We recently identified a short splicing variant of Mcl-1 short (Mcl-IS) and designated the known Mcl-1 as Mcl-1 long (Mcl-lL). Mcl-lL protein exhibits antiapoptotic activity and possesses the BH (Bcl-2 homology) 1, BH2, BH3, and transmembrane (TM) domains found in related Bcl-2 proteins. In contrast, Mcl-1 S is a BH3 domain-only proapoptotic protein that heterodimerizes with Mcl-lL. Although both Mc1-lL and Mcl-lS proteins contain BH domains fecund in other Bcl-2 family proteins, they are distinguished by their unusually long N-terminal sequences containing PEST (proline, glutamic acid, serine, and threonine) motifs, four pairs of arginine residues, and alanine- and glycine-rich regions. In addition, the expression pattern of Mcl-1 protein is different from that of Bcl-2 suggesting a unique role (or Mcl-1 in apoptosis regulation. Tankyrasel (TRF1-interacting, ankyrin-related ADP-related polymerasel) was originally isolated based on its binding to TRF 1 (telomeric repeat binding factor-1) and contains the sterile alpha motif (SAM) module, 24 ankyrin (ANK) repeats, and the catalytic domain of poly(adenosine diphosphate-ribose) polymerase (PARP). Previous studies showed that tankyrasel promotes telomere elongation in human cells presumably by inhibiting TRFI though its poly(ADP-ribosyl)action by tankyrasel . In addition, tankyrasel poly(ADP-ribosyl)ates Insulin-responsive amino peptidase (IRAP), a resident protein of GLUT4 vesicles, and insulin stimulates the PARP activity of tankyrase1 through its phosphorylation by mitogen-activated protein kinase (MAPK). ADP-ribosylation is a posttranslational modification that usually results in a loss of protein activity presumably by enhancing protein turnover. However, little information is available regarding the physiological function(s) of tankyrase1 other than as a PARP enzyme. In the present study, we found tankyrasel as a specific-binding protein of Mcl-1 Overexpression of tankyrasel led to the inhibition of both the apoptotic activity of Mel-lS and the survival action of Mcl-lL in mammalian cells. Unlike other known tankyrasel-interacting proteins, tankyrasel did not poly(ADP-ribosyl)ate either of the Mcl-1 proteins despite its ability to decrease Mcl-1 proteins expression following coexpression. Therefore, this study provides a novel mechanism to regulate Mcl-1-modulated apoptosis in which tankyrasel downregulates the expression of Mcl-1 proteins without the involvement of its ADP-ribosylation activity.

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Metoclopramide의 생체내대사(生體內代謝)에 미치는 안정제(安定劑)의 영향에 관한 실험적(實驗的) 연구(硏究) (Experimental Studies on the Metabolism of Metoclopramide: The Effects of a Few Stabilizers)

  • 지웅길
    • Journal of Pharmaceutical Investigation
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    • 제9권2호
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    • pp.11-21
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    • 1979
  • It has been reported from our department that a few agents, such as $K_2S_2O_5,\;NaHSO_3,$ nicotinamide have a marked stabilizing effect in vitro on metoclopramide which is relatively unstable compound. In order to study the effect of these stabilizers on the action of metoclopramide in vitro, the fate of this compound combined with $K_2S_2O_5,\;NaHSO_3$ and nicotinamide, respectively, was studied and furthermore, the change of the biological activity of metoclopramide due to these stabilizers was studied by using the isolated stomach strip of rat. The blood concentration of metoclopramide was measured by using Bakke's method at the various time after intravenous injection of the mixed metoclopramide solution with the stabilizers. In order to study the excretion of the drug, rabbits were anesthesized and catheterized into bladder for withdrawal of urine. After intravenous injection of the mixed metoclopramide solution, urine was collected for 5 hours and the conjugated forms of metoclopramide as well as the free form were determined by using Arita's method. In the biological study of the metoclopramide combined with stabilizers, the contractability of the isolated rat stomach strip was observed by using polygraph recorder. The results were following: 1. When metoclopramide was administered with nicotinamide as stabilizer, the blood concentration of the unchanged from and the rate of the clearance of this compound were very similar to that of metoclopramide alone. On the other hand, other stabilizers, $K_2S_2O_5\;and\;NaHSO_3$, brought about 40% decrease in blood concentration of the unchanged form at 15 min after intravenous injection however, the rate of clearance of metoclopramide with $K_2S_2O_5\;or\;NaHSO_3$ was very slow. 2. In the case of urinary excretion, the excretory pattern of the metabolites of metoclopramide with $NaHSO_3$ or nicotinamide was very similar to that of metoclopramide alone. But metodopramide plus $K_2S_2O_5$ group showed the maked depression of excretion for first 1 hour. 3. In composition of metabolites, when metoclopramide was administered with $K_2S_2O_5$ or $NaHSO_3$, the sulfonate conjugation was predominant. But the glucuronic acid conjugation was predominant in metoclopramide plus nicotinamide gronp. 4. In the experiments on the biological activity of the metoclopramide, this compound exhibited the marked contracting effect in isolatd rat stomach strip. Specially, the meetoclopramide combined with $K_2S_2O_5$ showed the strong contraction of the isolated strip, suggesting the potenciating effect of $K_2S_2O_5$ on the action of metoclopramide in the isolated strip.

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한국재래간장으로 부터 분리한 Bacillus subtilis globigii CCKS-118이 생성하는 pretense의 특성 및 작용양상 (Characteristics and Action Pattern of Protease from Bacillus Subtilis Globigii CCKS-118 in Korean Traditional Soy Sauce)

  • 최광수;조영제;임성일;이선호;손준호;최희진;이희덕;최청
    • Applied Biological Chemistry
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    • 제39권6호
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    • pp.460-465
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    • 1996
  • 한국재래간장으로 부터 분리한 Bacillus subtilis globigii CCKS-118가 생성하는 pretense 생산 최적조건은 2% soluble starch, 0.2% yeast extract, 0.1% $(NH_4)_2SO_4$, 0.2% $MgSO_4$, pH 7.5, $35^{\circ}C$에서 20시간이었다. 효소의 최적작용 pH와 온도는 pH 9.0, $50^{\circ}C$였으며, $pH\;6.0{\sim}11.0$의 범위와 $40^{\circ}C$이하에서 안정하였다. 금속이온중 $Cu^{2+}$에 의하여 활성이 증대되었으나 $Hg^{2+}$ 등에 의하여 효소활성이 저해되었다. Phenylmethylsuldonyl fluoride, ethylendiaminetetraacetic acid처리에 의해 활성이 저해되어 금속이온의 영향을 받는 serine pretense로 확인되었다. Km값은 $1.899{\times}10^{-4}M$, $V_{max}$값은 $34.36\;{\mu}g/min$이었으며, hemoglobin보다 casein을 더 잘 가수분해하였다.

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흰쥐 안면신경핵 세포의 전기생리학적 및 형태학적 특성 (ELECTROPHYSIOLOGICAL AND MORPHOLOGICAL CHARACTERISTICS OF FACIAL NUCLEUS IN RAT)

  • 최병주;조진화;배용철;김영진
    • 대한소아치과학회지
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    • 제27권3호
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    • pp.400-409
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    • 2000
  • 흰쥐의 안면신경핵을 구성하는 신경세포들의 시냅스 연결 양태 및 세포막 특성을 규명하기 위해 in vivo 필드전위 및 세포 내 전위 측정법을 이용하여 전기생리적 반응을 관찰하였다. 말초 안면신경 분지를 역행성으로 전기자극시 자극세기에 비례하여 전위의 크기가 증가되었고 필드 전위의 양태는 두 가지 반응으로 나타났는데 전기자극 직후 1ms 부근에서 정점을 나타내는 양태와 이와 더불어 $7\sim8ms$ 부근에서 후기 정점을 동반하는 양태가 있었다. 안면신경핵은 염색시 내측, 배외측, 중간측 및 외측등 4부분의 소핵으로 구분되었다. Neurobiotin으로 채워진 단일 신경세포를 형태학적으로 재구축하였는데 세포체는 추체형태를 나타내었고 주 수상돌기는 모든 방향으로 뻗어져 있었고 각 수상돌기의 영역은 해당 소핵 내에 한정되어 있었다. 일련의 과분극 전류 $(-1.2\sim+1.2nA)$를 세포내에 가하였을 때 동반되는 세포내 전위변화를 입력저항 값으로 계산하였을 때 그 기울기가 직선형으로 나타났다. 탈분극 전류를 세포내 주입시 지속적인 활동성 전위가 나타났으며 전류의 크기에 비례하여 각 전위의 개수가 증가하였고 spike-빈도 적응 현상이 나타났다. 그러나 시간 의존성 내향성 정류현상은 관찰되지 않았고 anodal break excitation이 나타났다. 이상의 실험결과로 보아 안면신경핵을 구성하고 있는 세포들 사이의 시냅스는 다양한 형태로 존재할 가능성이 있다고 사료되며 이들 시냅스간의 변화를 통하여 안면 신경마비, 반쪽 안면 경련, hypoglossal-facial anastomosis등에서 나타날 수 있는 임상적 신경성 증상 기전을 설명할 수 있을 것으로 여겨진다.

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Impacts of wave and tidal forcing on 3D nearshore processes on natural beaches. Part II: Sediment transport

  • Bakhtyar, R.;Dastgheib, A.;Roelvink, D.;Barry, D.A.
    • Ocean Systems Engineering
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    • 제6권1호
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    • pp.61-97
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    • 2016
  • This is the second of two papers on the 3D numerical modeling of nearshore hydro- and morphodynamics. In Part I, the focus was on surf and swash zone hydrodynamics in the cross-shore and longshore directions. Here, we consider nearshore processes with an emphasis on the effects of oceanic forcing and beach characteristics on sediment transport in the cross- and longshore directions, as well as on foreshore bathymetry changes. The Delft3D and XBeach models were used with four turbulence closures (viz., ${\kappa}-{\varepsilon}$, ${\kappa}-L$, ATM and H-LES) to solve the 3D Navier-Stokes equations for incompressible flow as well as the beach morphology. The sediment transport module simulates both bed load and suspended load transport of non-cohesive sediments. Twenty sets of numerical experiments combining nine control parameters under a range of bed characteristics and incident wave and tidal conditions were simulated. For each case, the general morphological response in shore-normal and shore-parallel directions was presented. Numerical results showed that the ${\kappa}-{\varepsilon}$ and H-LES closure models yield similar results that are in better agreement with existing morphodynamic observations than the results of the other turbulence models. The simulations showed that wave forcing drives a sediment circulation pattern that results in bar and berm formation. However, together with wave forcing, tides modulate the predicted nearshore sediment dynamics. The combination of tides and wave action has a notable effect on longshore suspended sediment transport fluxes, relative to wave action alone. The model's ability to predict sediment transport under propagation of obliquely incident wave conditions underscores its potential for understanding the evolution of beach morphology at field scale. For example, the results of the model confirmed that the wave characteristics have a considerable effect on the cumulative erosion/deposition, cross-shore distribution of longshore sediment transport and transport rate across and along the beach face. In addition, for the same type of oceanic forcing, the beach morphology exhibits different erosive characteristics depending on grain size (e.g., foreshore profile evolution is erosive or accretive on fine or coarse sand beaches, respectively). Decreasing wave height increases the proportion of onshore to offshore fluxes, almost reaching a neutral net balance. The sediment movement increases with wave height, which is the dominant factor controlling the beach face shape.

억압의 보상, 기녀(妓女)와 기녀시조(妓女時調) (The Compensation of Oppression, Ginyeo(妓女) & Ginyeo-sijo(妓女時調))

  • 김상진
    • 한국시조학회지:시조학논총
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    • 제43권
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    • pp.95-122
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    • 2015
  • 본 논문은 문학의 보상성을 기초로 한다. 즉 기녀(妓女)와 기녀시조(妓女時調)를 대상으로 그들 집단이나 작품의 중심에 있는 애정의 문제를 문학의 보상성에 근거하여 파악해 보려는 것이다. 구체적으로는 기녀라는 집단의 특성에서 야기되는 모성(母性)의 억압과 이에 대한 보상의 관계에서 기녀시조를 조망하였다. 본격적인 논의에 앞서 여성과 모성의 관계를 고전시가 전반을 통하여 살펴보았다. 그 결과 향가에서부터 고려속요, 규방가사와 개화기 가사 및 민요에 이르기까지 다양한 장르의 작품에서 모성이 발현되거나 모성을 주지로 삼고 있음을 알 수 있었다. 하지만 여성이면서도 여성의 지위를 온전히 획득할 수 없는 기녀들은 모성 표현의 기회를 상실했거나 억압하며 살 수 밖에 없는 처지였다. 이것은 기녀시조 창작에도 일정부분 영향을 미쳤을 텐데, 이러한 억압의 보상으로 말미암아 기녀시조는 몇 가지 특징을 지니게 된다. 억압의 보상이란 측면에서 봤을 때 기녀시조가 지니는 특성은 세 가지로 범주화 할 수 있다. 애절한 사랑의 헌신, 대담한 욕망의 표현, 재기발랄한 언어유희가 그것이다. 애절한 사랑의 헌신은 기녀시조에서 일반적으로 찾아볼 수 있는 모습으로, 현실에서의 애달픔으로 인해 그만큼 간절하게 사랑을 희구하는 것이다. 대담한 욕망의 표현은 사랑을 주지로 삼는다는 점에서는 전항과 일치하지만 전자가 소극적인데 반하여, 내재된 욕망의 대담함을 드러내며 적극성을 띈다는 점에서는 상반된다. 재기발랄한 언어유희는 수사적 표현과 관련되는 것인데, 중의적 표현이나 동음이의어가 여기에 포함된다. 요컨대 기녀집단에게 모성의 억압은 발분(發憤)의 계기가 되었을 것으로 추측할 수 있다. 그래서 사대부의 유배체험이 유배문학으로 발전하였듯이 이 또한 기녀시조의 발전에 일조하였을 것이라고 본다.

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Antinociceptive Effect of Intrathecal Nefopam and Interaction with Morphine in Formalin-Induced Pain of Rats

  • Cho, Soo Young;Park, A Reum;Yoon, Myung Ha;Lee, Hyung Gon;Kim, Woong Mo;Choi, Jeong Il
    • The Korean Journal of Pain
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    • 제26권1호
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    • pp.14-20
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    • 2013
  • Background: Nefopam, a non-opiate analgesic, has been regarded as a substance that reduces the requirement for morphine, but conflicting results have also been reported. The inhibition of monoamine reuptake is a mechanism of action for the analgesia of nefopam. The spinal cord is an important site for the action of monoamines however, the antinociceptive effect of intrathecal nefopam was not clear. This study was performed to examine the antinociceptive effect of intrathecal (i.t.) nefopam and the pattern of pharmacologic interaction with i.t. morphine in the formalin test. Methods: Male Sprague-Dawley rats were implanted with an i.t. catheter, and were randomly treated with a vehicle, nefopam, or morphine. Formalin was injected into the hind-paw 10 min. after an i.t. injection of the above experiment drugs. After obtaining antinociceptive $ED_{50}$ of nefopam and morphine, the mixture of nefopam and morphine was tested for the antinociceptive effect in the formalin test at a dose of 1/8, 1/4, 1/2 of $ED_{50}$, or $ED_{50}$ of each drug followed by an isobolographic analysis. Results: Intrathecal nefopam significantly reduced the flinching responses in both phases of the formalin test in a dose-dependent manner. Its effect, however, peaked at a dose of $30{\mu}g$ in phase 1 (39.8% of control) and $10{\mu}g$ during phase 2 (37.6% of control). The isobolograhic analysis indicated an additive interaction of nefopam and morphine during phase 2, and a synergy effect in antinociception during phase 1. Conclusions: This study demonstrated that i.t. nefopam produces an antinociceptive effect in formalin induced pain behavior during both phases of the formalin test, while interacting differently with i.t. morphine, synergistically during phase 1, and additively during phase 2.