• 대한약리학회지
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• 제30권1호
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• pp.29-37
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• 1994

배외측 뇌교의 전기자극은 척수 수준에서 동통의 역치를 증가시키고, 또한 말초로 부터 오는 유해성 자극에 의해 야기되는 척수후각세포의 흥분성을 억제하여 진통효과를 나타낸다. 이러한 진통효과는 noradrdnergic 원심신경을 매개로 한다고 하였지만, 이직까지 이를 직접적으로 뒷받침하는 신경화학적인 증거는 보고되지 않았다. 따라서 본 실험은 뇌교에 위치한 청반핵(Locus coeruleus)의 전기자극시, 척수 수준에서 일어나는 동통조절효과를 쥐꼬리 회피 반사(Tail Flick Reflex)를 이용해 관찰하고, 이러한 동통조절효과는 어떤 신경전달물질을 매개로해서 일어나며, 또한 생체내에서 직접 유리 되는지 살펴보기 위해 Push Pull technique을 이용해 척수액내 noradrenaline의 농도 변화를 HPLC로 측정하였다. 청반핵자극시의 동통조절기전을 알아보기위해 yohimbine, naloxone 그리고 vehicle의 3group 으로 나누어 각 길항제의 효과를 실험하였다. 청반핵 자극시 TF latency의 증가(>6.Ssec)를 보이는 역치 자극강도가 yohimbine $30{\mu}g$을 척수내로 투여한 후에는 $135\;{\mu}A$로서 안정시의 $55\;{\mu}A$에 비해 147% 증가되어 유의한 변화를 보여주었다(P<0.01, n=5). $Naloxone\;20{/mu}g$을 투여한 실험군 에서도 초기 역치자극강도 $54\;{\mu}A$에서 $120\;{\mu}A$로서 123% 증가되어 역시 유의한 변화를 보여주었다(P<0.01, n=5). 그러나 vehicle group에서는 투여 전, 후 역치자극강도의 변화가 없었다. 청반핵 자극이 없는 안정상태에서의 TF latency 값은 모두 3.1 sec였고 yohimbine과 naloxone투여후에는 각각 2.5 sec,2.6sec로 감소되어, 긴장성 억제가 차단되는 것으로 나타났다(각각 P<0.05,P<0.1,n=5).청반핵의 전기자극$(100\;{\mu}A)$은 척수액내 noradrenaline의 농도를 증가시켰으나(평균 4.18mg/ml에서 7.74 ng/ml로, p<0.05, n=10),dopamine의 농도는 증가되지 않았다. 이상의 결과는 청반핵 자극에 의한 척수내 동통조절효과는 opioid 계외에 부분적으로 noradrdnaline을 매개로 해서 이루어지며, 이에 관여하는 수용체는 ${\alpha}_2$ 임을 보여주었다.

• 대한기계학회논문집B
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• 제29권1호
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• pp.35-45
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• 2005

TR-E2 configuration designed by Bell Textron was tested in KARI 1-m wind tunnel. To explore aerodynamic characteristics for the given configuration, a $12\%$ scaled model was fabricated and tested. Wind tunnel test for TR-E2 had been performed by changing the incidence angles of wing and deflection angles of control surfaces. Test result showed that the lower wing incidence angle has more favorable lift to drag ratio compared with original design. Longitudinal and directional characteristics of TR-E2 were found to be stable for the pitch and yaw motions. However, the lateral stability of TR-E2 is not stable for certain control surface deflection.

• E2M - 전기 전자와 첨단 소재
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• 제10권5호
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• pp.467-472
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• 1997

In this study, we investigated the thickness dependence of thermal bleaching(TB) effect as well as photo-induced scalar phenomena, such as photodrakening(PD) effect and photorefraction(PR) change, in chalcogenide A $s_{40}$ G $e_{10}$S $e_{15}$ $S_{35}$ thin films. We found that when these films were exposed for 15 minutes using blue-pass filtered Hg lamp(~4300$\AA$) after annealing for 30 minutes around the glass transition temperature Tg(20$0^{\circ}C$), the refractive index change ($\Delta$n) was varied up to 0.02~0.46 according to each thickness condition and the optical energy gap ($\Delta$ $E_{op}$ ) was shifted to a longer wavelength of approximately 0.67eV, especially for 1000$\AA$-thickness. Also, the TB PD effects have been understood by the results related to optical absorption characteristics. The TB effect could be estimated as increasing the stabilization of amorphous chalcogenide films since absorption slope of extended regions(U) was not changed by annealing. On the other hand, the PD effect could be understood as due to the enhancement of disorder since U and the slope of Urbachs tail(1/F) around an absorption edge were decreased by exposing.ing.n edge were decreased by exposing.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 1996년도 제19회정기학술대회(The 19th Symposium of the Korean Society of Environmental Toxicology)
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• pp.61-61
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• 1996

Taxol is used as cancer therapeutic agent. It has been known as weak posotive of chromosome aberration assay in vitro in our previous results (Ryu et al., 1996) and potent clastogens in the mouse bone marrow micronucleus (Tinwell and Ashby, 1994). We performed microgel electrophoresis to determine the effect of taxol and it's precursor 10-deacetyl baccatin III(DAB) on DNA. Microgel electrophoresis is useful, rapid, simple, visual, and sensitive technique for measuring DNA breakage and repair mechanisms in mammalian 근ells. The range of concentration used for taxol were 854, 427, 213.5, 106.8, 53.4 Ug/ml, for DAB 910 ,455, 227.5 U9/ml, Cell viability always exceed 85%. We analyzed the results by using the special software of image analyzer for this comet assay (Komet 3.0). By using this image analyzer software , we can get the result as the tail moment ((mean of tail length - mean of head lengh) x tail%DNA/100). A slight increase in DNA migration was observed for taxol at the concentration of 854 Ug/m4 in the absence of S9 mixture. No increased DNA migration was observed after treatment with DAB.

• 한국간담췌외과학회지
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• 제26권2호
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• pp.178-183
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• 2022

Backgrounds/Aims: Proximal splenorenal shunt (PSRS) is considered a one-time treatment for noncirrhotic portal hypertension (NCPH) to prevent recurrent upper gastrointestinal (UGI) hemorrhage and long-term complications. Long-term shunt patency is necessary to achieve these. The lie of the shunt is a contributing factor to early shunt thrombosis. We investigated the role of resection of the distal tail of pancreas (caudal pancreatectomy [CP]) in improving the lie of shunt and decreasing shunt thrombosis. Methods: This was a retrospective cohort study of patients with NCPH who underwent PSRS between 2014-2020 in JIPMER, Puducherry, India. CP was performed in patients with a long tail of pancreas, with the tip of pancreatic tail extending up to splenic hilum on preoperative CT. Perioperative parameters and shunt patency rate of patients who underwent PSRS with CP (Group A) were compared with patients undergoing conventional PSRS (Group B). Statistical analysis was performed using the Mann-Whitney U test and χ² test. Results: Eighty four patients with NCPH underwent PSRS (extrahepatic portal vein obstruction = 39; noncirrhotic portal fibrosis = 45). Blood loss was lower (p = 0.002) and post-shunt fall in portal pressure higher (p = 0.002) in Group A. Shunt thrombosis rate was lower (p = 0.04) while rate of complete variceal regression (p = 0.03) and biochemical pancreatic leak (p = 0.01) were higher in Group A.There was no clinically relevant pancreatic fistula in either group. Conclusions: CP is a safe and useful technique for reducing shunt thrombosis after PSRS in patients with NCPH by improving the lie of shunt.

• Journal of Species Research
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• 제5권3호
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• pp.318-323
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• 2016

Acrobeles ciliatus (von Linstow, 1877) and Plectus parietinus (Bastian, 1865) are newly collected from Korea. Acrobeles is similar to those nematode belongs to Rhabditidae and Panagrolaimidae by having terminal bulb without medium bulb but different by having complex, vines shaped labial attachment. A. ciliatus differed from other Acrobeles species by lateral fields with two incisures, primary axils U-shaped, and secondary axils V-shaped. Head region set off with the neck, three high labial probolae present, each having 5 tines at inner margins and 5-7 at outer margins, and two elongate apical tines. Also, it differs from the longer female body. Plectus parietinus is distinguished from all other species of Plectus by the prominent hypodermal glands, the relatively small amphid, the distinct and well set-off lips and by the subdorsal distal caudal seta on the left side of the tail. Stoma without stylet. Oesophagus about 1/4 of total body length with terminal bulb. Anus ca. $100{\mu}m$ from posterior extremity. Vulva is at middle of body. Have spinneret on tail tip.

• 한국의류학회지
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• 제39권3호
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• pp.394-407
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• 2015

Prior research highlighted personalized services as a crucial antecedent to website loyalty, yet little has been discussed on the underlying mechanism. The current study explores the intervening effects of the three psychological constructs in the personalization-loyalty relationship: cognitive efficiency, perceived enjoyment, and socialness. An experiment was conducted with a total of 414 U.S. shoppers on a fictitious e-tail site for jeans that employed different levels of personalized content. The results found that the participants exposed to the high-level personalization condition reported a higher cognitive efficiency and higher socialness perception regarding the fashion e-tail site; however, no direct effect of intensity of e-personalization was found on perceived enjoyment. Cognitive efficiency and enjoyment perceptions on the site significantly increased customers' loyalty intentions regarding the site, while website socialness perception had no direct effect on loyalty intentions. Website socialness showed indirect effects on website loyalty intentions only through cognitive efficiency and perceived enjoyment; however, no direct effect from website socialness was found. Implications and limitations of the study were discussed.

• 한국수산과학회지
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• 제53권1호
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• pp.83-89
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• 2020

This study provides a detailed morphological description of larvae obtained from Urocampus nanus and Syngnathus schlegeli male brood fish over 20 days of culture in the laboratory. In both species, mating takes place when several males each spread their brood pouch like a wing to attract a female's attention. When the female begins to swim upward, the males follow her and receive her eggs in their brood pouches. Newborn larvae of U. nanus and S. schlegeli had already completed formation of dorsal and caudal fin rays, but not of pectoral fin rays. Pectoral fin rays were completely formed 15 days after release in S. schlegeli and 20 days after release in U. nanus. The ratio of caudal fin length to standard length increased until 8 days and decreased thereafter in S. schlegeli, while in U. nanus this ratio declined continuously after hatching. The larvae of the two species were very similar in external morphology, but well distinguished by the number of dorsal fin rays (15-16 in U. nanus vs. 39-43 in S. schlegeli), the presence of a membrane under the tail (absent in U. nanus vs. present in S. schlegeli), and the presence of melanophores in the dorsal fin (present in U. nanus vs. absent in S. schlegeli). Based on this study, U. nanus appears to be evolutionally more similar to pipefish than to seahorse.

• Journal of Korean Neurosurgical Society
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• 제55권3호
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• pp.131-135
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• 2014

Objective : With the growing interests of bacteria as a targeting vector for cancer treatment, diverse genetically engineered Salmonella has been reported to be capable of targeting primary or metastatic tumor regions after intravenous injection into mouse tumor models. The purpose of this study was to investigate the capability of the genetically engineered Salmonella typhimurium (S. typhimurium) to access the glioma xenograft, which was monitored in mouse brain tumor models using optical bioluminescence imaging technique. Methods : U87 malignant glioma cells (U87-MG) stably transfected with firefly luciferase (Fluc) were implanted into BALB/cAnN nude mice by stereotactic injection into the striatum. After tumor formation, attenuated S. typhimurium expressing bacterial luciferase (Lux) was injected into the tail vein. Bioluminescence signals from transfected cells or bacteria were monitored using a cooled charge-coupled device camera to identify the tumor location or to trace the bacterial migration. Immunofluorescence staining was also performed in frozen sections of mouse glioma xenograft. Results : The injected S. typhimurium exclusively localized in the glioma xenograft region of U87-MG-bearing mouse. Immunofluorescence staining also demonstrated the accumulation of S. typhimurium in the brain tumors. Conclusion : The present study demonstrated that S. typhimurium can target glioma xenograft, and may provide a potentially therapeutic probe for glioma.

• 산업경영시스템학회지
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• 제43권4호
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• pp.93-106
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• 2020

This research explores how imported automobile companies can develop their strategies to improve the outcome of their recalls. For this, the researchers analyzed patterns of recall demand, classified recall types based on the demand patterns and examined response strategies, considering plans on how to procure parts and induce customers to visit workshops, recall execution capacity and costs. As a result, recalls are classified into four types: U-type, reverse U-type, L- type and reverse L-type. Also, as determinants of the types, the following factors are further categorized into four types and 12 sub-types of recalls: the height of maximum demand, which indicates the volatility of recall demand; the number of peaks, which are the patterns of demand variations; and the tail length of the demand curve, which indicates the speed of recalls. The classification resulted in the following: L-type, or customer-driven recall, is the most common type of recalls, taking up 25 out of the total 36 cases, followed by five U-type, four reverse L-type, and two reverse U-type cases. Prior studies show that the types of recalls are determined by factors influencing recall execution rates: severity, the number of cars to be recalled, recall execution rate, government policies, time since model launch, and recall costs, etc. As a component demand forecast model for automobile recalls, this study estimated the ARIMA model. ARIMA models were shown in three models: ARIMA (1,0,0), ARIMA (0,0,1) and ARIMA (0,0,0). These all three ARIMA models appear to be significant for all recall patterns, indicating that the ARIMA model is very valid as a predictive model for car recall patterns. Based on the classification of recall types, we drew some strategic implications for recall response according to types of recalls. The conclusion section of this research suggests the implications for several aspects: how to improve the recall outcome (execution rate), customer satisfaction, brand image, recall costs, and response to the regulatory authority.