• 생태와환경
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• 제33권4호통권92호
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• pp.380-386
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• 2000

순수배양한 조류와 자연군집의 식물플랑크톤을 대상으로 유기인삼염해분해효소의 kinectic parameter를 비교하였고, 용존무기인의 농도와 각 parameter와의 관계를 알아보았다. 기질과의 친화력을 나타내는 AP$_{ase}$의 K$_{m}$은 조류의 종마다 매우 상이한 값을 보였다. Chlorella sp.를 제외한 녹조류가 다른 종에 비해 큰 K$_{m}$을 보였고, 규조류와 Chlorella sp.에서 작은 K$_{m}$을 보였다. 순수배양한 남조류 Anabaena flos-aquae에서 extracelluar free enzyme 의 K$_{m}$이 cell-bound enzyme의 K$_{m}$보다 작았다. 자연군집인 소양호에서는 남조류 Anabaena sp. 가 우점하였던 여름의 식물플랑크톤의 K$_{m}$이 규조류가 우점하였던 봄의 군집보다 컸다. AP$_{ase}$ 활성도의 V$_{max}$는 수중의 DIP 농도보다는 식물플랑크톤의 세포내 인의 함량에 직접적인 영향을 받는 것으로 나타났다. 소양호에서 가을부터 봄까지 extracelluar free enzyme의 활성도가 총 AP$_{ase}$ 활성도의 36${\sim}$97%의 기여를 하였는데, 이는 이 시기에 extracelluar free enzyme이 호수의 인순환에서 매우 중요한 요인으로 작용한다는 것을 시사한다. 그리고 extracelluar free enzyme과 총 AP$_{ase}$의 K$_{m}$이 거의 비슷하였는데, 이는 extracelluar free enzyme이 조류로부터 기인되었기 때문으로 사료된다.

• 생태와환경
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• 제35권4호통권100호
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• pp.249-256
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• 2002

안동호에서 1993년부터 2000년까지 영양상태와 인부하량의 장기적인 변화를 조사하였다. 조사항목은 탁도, 수온, 투명도, 인, 질소 및 엽록소 a 농도 등이며, 댐 앞지점에서 월 1회 조사하였다. 유역으로부터의 인부하량은 주 유입수에서 주 1회 혹은 우기시 수시로 조사된 자료와 유입수량으로부터 산출하였다. 양어장으로부터의 인부하량은 사료공급량과 원단위로부터 산출하였다. 여름에 히소투명도 값이 1993년과 1994년에는 약 2m정도이었으나, 1998년에는 약 1m를 보였다. 표충의 총인 농도는 1993년에 $11-30\;mgP/m^3$에서 1998년에는 $18-42\;mgP/m^3$으로 약간 증가하였다. 그러나 2000년에는 $8-13\;mgP/m^3$으로 회복되었다. 표층의 총질소는 1993년에 1.81-2.96 mgN/L에서 2000년에는 1.17-1.80 mgN/L로 약간 감소하였다. TN/TP비는 1993년에 82-281이었으나 1998년에는 21-143로 감소하였다. 그러나 2000년에는 TP의 감소에 따라 101-209로 다시 증가하였다. 여름에 엽록소 a 농도는 1993년부터 1997년까지 $4.8-16.2\;mg/m^3$의 범위를 보였으나 1998년 이후에는 $3.7-5.2\;mg/m^3$으로 다소 감소되었다. 안동호의 영양상태는 1996년까지 점차적으로 증가되어왔으나 그 이후 감소되고 있는 것으로 나타났다 영양상태 회복의 주요 요인은 1998년 4월에 양어장의 철거에 따른 것으로 판단된다.

• Nuclear Medicine and Molecular Imaging
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• 제42권6호
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• pp.485-487
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• 2008

Ectopic thyroid is not common disease and double ectopic thyroid is rare. Until January of 2008, dual ectopic thyroid has been reported only 23 cases in international literatures. Tc-99m sodium pertechnetate scan is playing an important role in the diagnosis of ectopic thyroid. In most of the cases, dual lingual thyroid tissues could be detected as two radiotracer uptake foci. We report a case of dual lingual thyroid mimicking mono-lingual thyroid in the anterior view of thyroid scan. Lateral view helped in this case to detect the dual lingual thyroid. With lateral view, the anatomical position and relationship could be examined in more detail.

• Journal of Microbiology and Biotechnology
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• 제25권3호
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• pp.343-352
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• 2015

H9 is an ethanol extract prepared from nine traditional/medicinal herbs. This study was focused on the anticancer effect of H9 in non-small-cell lung cancer cells. The effects of H9 on cell viability, apoptosis, mitochondrial membrane potential (MMP; ${\Delta}\psi_{m}$), and apoptosisrelated protein expression were investigated in A549 human lung cancer cells. In this study, H9-induced apoptosis was confirmed by propidium iodide staining, expression levels of mRNA were determined by reverse transcriptase polymerase chain reaction, protein expression levels were checked by western blot analysis, and MMP (${\Delta}\psi_{m}$) was measured by JC-1 staining. Our results indicated that H9 decreased the viability of A549 cells and induced cell morphological changes in a dose-dependent manner. H9 also altered expression levels of molecules involved in the intrinsic signaling pathway. H9 inhibited Bcl-xL expression, whereas Bax expression was enhanced and cytochrome C was released. Furthermore, H9 treatment led to the activation of caspase-3/caspase-9 and proteolytic cleavage of poly(ADP-ribose) polymerase; the MMP was collapsed by H9. However, the expression levels of extrinsic pathway molecules such as Fas/FasL, TRAIL/TRAIL-R, DR5, and Fas-associated death receptor were downregulated by H9. These results indicated that H9 inhibited proliferation and induced apoptosis by activating intrinsic pathways but not extrinsic pathways in human lung cancer cells. Our results suggest that H9 can be used as an alternative remedy for human non-small-cell lung cancer.

• 한국수의병리학회지
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• 제2권1호
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• pp.17-24
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• 1998

This is the first report of c-Jun protein expression and mRNA in a pancreatic islet in a nonobese diabetic(NOD) state mice. In this experiment NOD mice with insulin-dependent diabetes mellitus type I at age 16 weeks(n=7) just before death(n=4) were used. The control group consist of prediabetic NOD(8 weeks n=7) and ICR(8 weeks n=7 and 16 weeks n=7) mice. c-Jun positive cells in the pancreatic islet of NOD mice were localized in the same positions as a-glucagon producing cells. immunoreactivity was negative in the prediabetic NOD(8 weeks) and ICR(8 weeks and 16 weeks) mice. The number of c-Jun positive cells in mice with severe diabetic state just before death were significantly decreased when compared to NOD(16 weeks) mice. Expression of c-Jun in mRNA level was assessed by RT-PCR method. The levels of mRNA in NOD(16 weeks) mice group were elevated in total pancreatic tissues. The present results suggest that the induction of proto-oncogene protein may be of significance in assessing cell specific injury and may play a functional role between pancretic islet $\alpha$-cells and $\beta$-cells in the diabetic state.

• 한국농공학회논문집
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• 제53권1호
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• pp.37-45
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• 2011

Mandae watershed in Gangwon province has been known as one of soil erosion hot spot watersheds within Hanggang basin. Thus numerous efforts have been made to reduce soil erosion and pollutant loads into receiving watershed. However, proper best management practices have not been suggested because no monitoring flow and water quality data were available. Thus, modeling technique could not be utilized to evaluate water quality issue properly at Mandae watershed to develop and implement the best management practices. In this study, the SWAT model was applied to the Mandae watershed, Gangwon province to evaluate the SWAT prediction ability and water quality improvement with vegetated filter strip (VFS) in this study. The Nash-Sutcliffe model efficiency (NSE) and Coefficient of determination ($R^2$) values for flow simulation were 0.715 and 0.802, respectively, and the NSE and $R^2$ values were 0.903 and 0.920 for T-P simulation indicating the SWAT can be used to simulate flow and T-P with acceptable accuracies. The SWAT model, calibrated for flow and T-P, was used to evaluate water quality improvement with the VFS in agricultural fields. It was found that approximately 56.19 % of T-P could be reduced with vegetated filter strip of 5 m at the edge of agricultural fields within the watershed (34.86 % reduction with VFS of 1m, 48.29 % with VFS of 3 m). As shown in this study, the T-P, which plays key roles in eutrophication in the waterbodies, can be reduced with proper installation of the VFS.

• 대한핵의학회지
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• 제28권3호
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• pp.313-316
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• 1994

본 연구에서는 Tc-99m DTPA 뇌조조영술에서 48시간 지연영상을 얻는 것이 가능한지, 그리고 이 영상이 어떤 의의를 가지고 있는지에 대해 검토하여 보았다. 1991년 3월부터 1994년 4월까지 전남대학교병원 핵의학과에서 48시간 지연영상까지 촬영하였던 Tc-99m DTPA 뇌조조영술 38예를 대상으로 하였다. Tc -99m DTPA 37-111MBq을 요추천자하여 지주막하강에 투여하고 2, 6, 24, 48시간에 두부의 전면상과 양측면상을 얻었다. 뇌조조영술 소견의 분류는 I, II, IIIa, IIIb, IV형으로 나누어 2명의 핵의학의사가 독립적으로 하였으며, 서로 판독결과가 일치하지 않는 경우는 합의에 의하여 결정하였고, 뇌실역류의 지속성여부는 24시간 및 48시간에 각각 판단하였다. 대상환자 전례에서 48시간 영상도 판독가능하였다. 뇌실역류가 24시간에 지속되었으나 48시간에 소실된 경우는 비교통성수두증에서는 없었고, 교통성수두증 30예중 7예(23.3%)에서 관찰할 수 있었으며, 따라서 분류가 IV형으로부터 IIIa형으로 4예, IIIb형으로 3예에서 변경되었다. 이중 단락수술을 시행한 예는 16예로, II형에서 1예, III형에서 6예, IV형에서 9예였으며, 수술후 임상증상이 호전된 예는 II형 1예 중 1예 (100%), III형 6예 중 3예(50%), IV형 9예 중 8예 (89%)였다. 수술을 시행한 IIIa형 중 1예는 24시간 까지의 영상으로는 IV형으로 분류되었으나 48시간 영상에서 IIIa형으로 분류된 예였으며, 단락수술후 임상증상이 개선되지 않았다. 결론적으로, Tc-99m DTPA 뇌조조영술에서도 48시간 영상이 가능하였으며, 수술적응증 판단에 유용한 방법으로 사용될 수 있으리라 사료되었다.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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• pp.279-284
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• 2005

We investigated the impedance matching characteristics of UHF-band RFID tag antenna and tag chip for increased reading range. A voltage multiplier designed using 0.4 $\mu$m zero-$V_T$ MOSFET showed that DC output voltage of about 2 V can be obtained using standard CMOS process. The input impedance of the voltage multiplier was examined to achieve impedance matching to the RFID tag antenna using analytical and numerical approaches. The input impedance of the voltage multiplier could be varied in a wide range by selecting the size of MOSFET and the number of multiplying stages, and thus can be impedance matched to a tag antenna in presence of other tag circuit blocks. A meander line inductively-coupled RFID tag antenna operating at UHF band also shows the feasibility of impedance matching to tile RFID tag chip.

• BMB Reports
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• 제51권11호
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• pp.596-601
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• 2018

Colon cancer is one of the most lethal and common malignancies worldwide. STK899704, a novel synthetic agent, has been reported to exhibit anticancer effects towards numerous cancer cells. However, the effect of STK899704 on the biological properties of colon cancer, including cancer cell migration and cancer stem cells (CSCs), remains unknown. Here, we examined the inhibitory effect of STK899704 on cell migration and CSC stemness. In the wound healing assay, STK899704 significantly inhibited the motility of colon cancer cells. Furthermore, STK899704 downregulated the mRNA expression levels of the cell migration mediator focal adhesion kinase (FAK). STK899704 also suppressed mitogen-activated protein kinase kinase and extracellular signal-regulated kinase, which are downstream signaling molecules of FAK. Additionally, STK899704 inhibited stemness gene expression and sphere formation in colon cancer stem cells. These results suggest that STK899704 can be used to treat human colon cancer.

• 생약학회지
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• 제30권4호
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• pp.404-408
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• 1999

SH2 domains and their associated catalytic or noncatalytic proteins constitute critical signal transduction targets for drug discovery. Grb2 associates with phosphotyrosine sites of the activated receptors or Shc via their SH2 domain to link receptor tyrosine kinases to ras signalling. Blocking of the Grb2-Shc complex may be to intervene the oncogenic signal transduction pathways and to develop a new antitumor drug. In the search for blockers of Grb2 SH2-Shc interaction, Lutein, a family of carotenoids, was isolated from the extract of the leaf of Agastache rugosa O. Kuntze as SH2 domain antagonists. The $IC_{50}$ of Lutein against Grb2-Shc binding was $6.8\;{\mu}M$.