• 한국구조물진단유지관리공학회 논문집
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• 제24권5호
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• pp.86-94
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• 2020

고 흡수성 폴리머(SAP)가 콘크리트에 혼입되면 슬럼프가 급격하게 감소하여 시공성이 저하되며, 수분 흡수·방출 과정으로 내부 양생 효과를 얻을 수 있고, 콘크리트의 내부 공극을 증가시킨다. 본 연구에서는 감수제를 사용하여 시공성을 확보한 SAP 혼입 콘크리트의 압축강도 및 동결융해 저항성, 염화물 침투 저항성을 평가하여 내부 양생과 공극의 영향을 평가하였다. 또한 콘크리트의 양생 조건을 수중 양생과 봉함 양생으로 구분하여 SAP의 내부 양생 효과를 평가하였다. 실험 결과, SAP 혼입율이 증가할수록 감수제 사용량은 증가하였으며, 압축강도는 SAP 혼입율 1.5%가 가장 큰 압축강도를 나타냈다. 특히, 봉함 양생의 경우 수중 양생보다 큰 압축강도를 나타냈으며, 유효 물-시멘트 비 감소와 내부 양생 효과에 의해 압축강도가 증가한 것으로 판단된다. SAP를 1.0~1.5% 혼입하면 AE제를 혼입한 경우와 유사하게 동결융해 저항성이 개선되었으며, SAP를 1.0% 이상 사용하면 염화물 침투 저항성이 개선되었다. 최적의 SAP 혼입율은 1.5%이며, 2.0% 이상의 혼입율은 압축강도 및 동결융해 저항성에 악영향을 준다.

• 대한한방내과학회지
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• 제29권3호
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• pp.641-656
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• 2008

This study was done to investigate the effect of Gamichungyeoldodam-tang (GCDT) in DOCA-salt induced hypertensive rats. The results were obtained as follows : GCDT showed safety against cytotoxicity and toxicity in the liver and the kidney. GCDT showed an inhibitory effect on ACE. GCDT significantly decreased the heart rate and the blood pressure in DOCA-salt induced hypertensive rats. GCDT significantly decreased the levels of aldosterone in DOCA-salt induced hypertensive rats. GCDT significantly decreased the levels of dopamine, norepinephrine, and epinephrine in DOCA-salt induced hypertensive rats. GCDT significantly decreased the levels of chloride in DOCA-salt induced hypertensive rats. These results suggest that GCDT might be effective in treatment of hypertension.

• 한국식품과학회지
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• 제43권1호
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• pp.6-11
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• 2011

PVC 및 PVDC 재질의 식품포장에 잔류할 수 있는 원료물질인 VC 및 VDC를 PLOT Q 컬럼이 장착된 headspace-GC/MS를 이용하여 분석하였다. VC 및 VDC 각각에 대하여 m/z=61, 62, 64 및 m/z=61, 96, 98 이온을 선택 이온으로 하여 분석하였으며, 내부표준 물질로는 1-CP를 사용하였다. 분석법 검증결과 본 연구에서 도입한 분석법은 유럽연합의 재질규격 시험에 적합하였으며, 국내유통 PVC 및 PVDC 재질의 식품 포장 103 품목에 대한 분석 결과, PVDC 식품포장 1건에서 재질 중 VDC가 검출되었으나, 이는 유럽연합에서 설정하고 있는 재질규격 이내에 드는 미미한 수준이었으며, 나머지 모든 시료에서는 VC 및 VDC가 검출되지 않았다.

• 생약학회지
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• 제33권1호통권128호
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• pp.13-17
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• 2002

Helicobacter pylori infection is associated with type B gastritis, peptic ulcer, and gastric cancer. The vacuolation of cells induced by H. pylori is thought to be essential for the initiation and maintenance of gastric infection. The roles of H. pylori cytotoxin, urease, and ammonia in the vacuolation of HeLa cells were determined. Ammonium chloride augmented the neutral red uptake induced by H. pylori toxin. Acetohydroxamic acid (AHA) failed to block the neutral red uptake induced by H. pylori toxin. Leweifang significantly prevented the vacuolation of HeLa cells induced by H. pylori toxin or H. pylori toxin and ammonium chloride. Further investigation is required to determine the mechanisms of Leweifang for the inhibition of vacuole formation of eukaryotic cells in response to the H. pylori toxin.

• 대한약침학회지
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• 제6권3호
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• pp.49-55
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• 2003

This study was undertaken to define the effect of ChungSangSaWhaTang on the norepinephrine-induced arterial contraction and the mechanism of ChungSangSaWhaTang-induced relaxation. In order to investigate the effect of ChungSangSaWhaTang on contracted rabbit carotid arterial strips, transverse strips with intact or damaged endothelium were used for the experiment using organ bath. To analyze the mechanism of ChungSangSaWhaTang-induced relaxation, ChungSangSaWhaTang extract infused into contracted arterial strips induced by norepinephrine after treatment of indomethacin, $N_{\omega}$-nitro-L-arginine, or tetraethylammonium chloride. ChungSangSaWhaTang relax arterial strip with endothelium contracted by norepinephrine, but in the strips without endothelium, ChungSangSaWhaTang-induced relaxation was significantly inhibited. The endothelium-dependent relaxation induced by ChungSangSaWhaTang was decreased by the pretreatment of $N_{\omega}$-nitro-L-arginine, but it was not observed in the strips pretreated with indomethacin or tetraethylammonium chloride. We suggest that ChungSangSaWhaTang may inhibit agonist-induced contraction through the formation of nitric oxide in the vascular endothelial cells.

• Archives of Pharmacal Research
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• 제28권3호
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• pp.370-375
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• 2005

The objective of this study was to develop a new reverse micelle-based microencapsulation technique to load tetracycline hydrochloride into PLGA microspheres. To do so, a reverse micellar system was formulated to dissolve tetracycline hydrochloride and water in ethyl formate with the aid of cetyltrimethylammonium bromide. The resultant micellar solution was used to dissolve 0.3 to 0.75 g of PLGA, and microspheres were prepared following a modified solvent quenching technique. As a control experiment, the drug was encapsulated into PLGA microspheres via a conventional methylene chloride-based emulsion procedure. The micro­spheres were then characterized with regard to drug loading efficiency, their size distribution and morphology. The reverse micellar procedure led to the formation of free-flowing, spherical microspheres with the size mode of 88 ~m. When PLGA microspheres were prepared follow­ing the conventional methylene chloride-based procedure, most of tetracycline hydrochloride leached to the aqueous external phase: A maximal loading efficiency observed our experimental conditions was below $5\%$. Their surfaces had numerous pores, while their internal architecture was honey-combed. In sharp contrast, the new reverse micellar encapsulation technique permitted the attainment of a maximal loading efficiency of 63.19 $\pm$$0.64\%$. Also, the microspheres had smooth and pore-free surfaces, and hollow cavities were absent from their internal matrices. The results of this study demonstrated that PLGA microspheres could be successfully prepared following the new reverse micellar encapsulation technique.

• Journal of Yeungnam Medical Science
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• 제35권1호
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• pp.89-93
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• 2018

Idiopathic non-cirrhotic portal hypertension (INCPH) is a disease with an uncertain etiology consisting of non-cirrhotic portal hypertension and portal pressure increase in the absence of liver cirrhosis. In INCPH, patients exhibit normal liver functions and structures. The factors associated with INCPH include the following: Umbilical/portal pyremia, bacterial diseases, prothrombic states, chronic exposure to arsenic, vinyl chloride monomers, genetic disorders, and autoimmune diseases. Approximately 70% of patients present a history of major variceal bleeding, and treatment relies on the prevention of complications related to portal hypertension. Autoimmune disorders associated with INCPH are mainly systemic sclerosis, systemic lupus erythematosus and rheumatoid arthritis. To the best of our knowledge, a case of ankylosing spondylitis (AS) associated with INCPH has not been reported thus far. Therfore, we report our experience of a patient with AS accompanied by INCPH, who showed perisplenic varices with patent spleno-portal axis and hepatic veins along with no evidence of cirrhosis on liver biopsy, and provide a brief literature review.

• 한국건설순환자원학회논문집
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• 제4권3호
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• pp.259-268
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• 2016

염해에 노출된 콘크리트 구조물의 내구수명 평가는 크게 결정론적 방법과 확률론적 방법으로 분류할 수 있으며, 다양한 설계인자에 따라 내구수명은 크게 변화한다. 본 연구에서는 시간의존성 확산계수 및 내부영향인자(기본확산계수, 임계염화물량, 시간지수)를 고려하여 변화하는 내구적 파괴확률과 이에 따른 내구수명을 도출하였다. 임계 염화물량이 133.3% 증가할 때, 내구수명은 결정론적 방법에서 134.0~145.4%의 증가비를 나타내었으며, 확률론적 방법에서는 149.2%~152.5% 증가비를 나타내었다. 시간지수가 200% 증가할 경우, 내구수명의 증가비율은 결정론적 방법에서 323.8%, 확률론적 방법에서 346.0%로 증가하였다. 시간의존성 확산계수를 사용하여 과다설계를 방지할 수 있는 합리적인 확률론적 내구설계를 수행할 수 있었으며, 혼화재료를 사용하여 시간지수를 증가시키는 것이 매우 효과적인 내구수명 연장방안임을 알 수 있었다.

• 한국구조물진단유지관리공학회 논문집
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• 제16권6호
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• pp.73-81
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• 2012

콘크리트 구조물은 일반적으로 동결융해 작용을 받는 조건에 노출되고, 이러한 동결융해작용은 콘크리트의 공극구조를 변화시키고, 콘크리트의 내구성을 저하시킬 우려가 있다. 따라서 본 연구에서는 동결융해작용에 의한 콘크리트 내부공극구조 변화와 동결융해작용을 받은 콘크리트의 내구특성을 평가하고자 하였다. 실험결과, 기존의 동결융해 평가기법에 따르면 모든 배합에서 우수한 내구성능을 나타내었으나, 동결융해 작용에 노출됨에 따라 50~100nm 크기의 공극이 크게 증가하며, 콘크리트 염화물침투저항성이 저하하였다. 수중양생 콘크리트의 공극구조와 염화물 침투저항성은 선형관계를 보이지만, 동결융해작용을 받으면 내부공극구조의 변화로 선형관계가 저하하였다. 동결융해작용과 염화물침투를 동시에 받는 구조물의 내구성 평가기준에 대한 재검토가 필요할 것으로 판단된다.

• 동의생리병리학회지
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• 제24권3호
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• pp.430-438
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• 2010

This study was done to investigate the effect of SHCG on hypertension in spontaneous hypertensive rats. SHR was sensitized and challenged with Sihogayonggolmoryeotanghabcheongsimyeonjaemgagambang (SHCG) for 4 weeks. The 3 groups have 6 rats, respectively. Experimental group was treated with 56.7 mg/kg of SHCG orally and control group was treated with 56.7 mg/kg of normal saline instead. SHCG significantly showed safety against cytotoxicity on hFCs and toxicity in the liver. SHCG significantly decreased the blood pressure and the heart rate. SHCG significantly decreased the levels of aldosterone. SHCG significantly decreased the levels of dopamine, norepinephrine, and epinephrine. SHCG significantly decreased the levels of potassium and chloride. SHCG significantly decreased the levels of uric acid and creatinine. These results suggest that SHCG might be hopeful in treatment of hypertension.