• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.5
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• pp.86-94
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• 2020

When the Superabsorbent Polymer (SAP) is added into concrete, the slump decreases rapidly, deteriorating the workability, the internal curing effect can be obtained through the water absorption and discharge process, and the internal voids of the concrete are increased. In this study, the effects of internal curing and voids were evaluated by evaluating the compressive strength, freeze-thaw resistance, and chloride penetration resistance of SAP-adding concrete that secured workability using a water reducing agent. Also, the internal curing effect of SAP was evaluated by dividing the curing conditions of concrete into water curing and sealed curing. From the result, as the SAP adding ratio increased, the amount of water reducing agent increased, and as for the compressive strength, the SAP adding ratio of 1.5% showed the greatest compressive strength. In particular, in the case of sealed curing showed higher compressive strength than the water curing. It is considered that the compressive strength increased due to the reduction of the effective water-cement ratio and the internal curing effect. Adding 1.0~1.5% of SAP improved the freeze-thaw resistance similar to the case of adding the AE agent, and the addition of more than 1.0% of SAP improved the chloride penetration resistance. The optimal adding ratio of SAP is 1.5%, and the adding ratio of 2.0% or more adversely affects the compressive strength and freeze-thaw resistance.

• The Journal of Internal Korean Medicine
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• v.29 no.3
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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.

• Korean Journal of Food Science and Technology
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• v.43 no.1
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• pp.6-11
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• 2011

Vinyl chloride (VC) and vinylidene chloride (VDC), which may be present in poly(vinyl chloride) (PVC) and poly(vinylidene chloride) (PVDC) food packaging, were analyzed by using a headspace-gas chromatograph (GC)/mass spectrometer (MS) equipped with a PLOT Q column. 1-Chloropropane (1-CP) was used as an internal standard. The determinations of VC and VDC were carried out by monitoring the characteristic ions for each compound: m/z=61, 62, 64 and m/z=61, 96, 98, respectively. The method validated in this study can be suitable for the compliance test of EU regulation. Among 103 food packaging samples, VC and VDC were not detected, except in one PVDC food package. However, the detected level of VDC in the sample was below the EU regulatory specific limitation.

• Korean Journal of Pharmacognosy
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• v.33 no.1 s.128
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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.

• Journal of Pharmacopuncture
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• v.6 no.3
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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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• v.28 no.3
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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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• v.35 no.1
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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.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.3
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• pp.259-268
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• 2016

The service life evaluation in RC(Reinforced Concrete) structure exposed to chloride attack can be classified into deterministic and probabilistic method, and it significantly varies with design parameters. The present work derives PDF (Probability of Durability Failure) and the related service life considering time-dependent diffusion coefficient and internal parameters such as reference diffusion coefficient, critical chloride content, and time-exponent. When critical chloride content increases to 133.3%, the changing ratios of service life are 134.0~145.4% for deterministic method and 149.2%~152.5% for probabilistic method, respectively. In the case of increasing time-exponent to 200%, they increase to 323.8% for deterministic method and 346.0% for probabilistic method. Through adopting time-diffusion coefficient for probabilistic method, reasonable service life evaluation can be achieved, and it is also verified that increasing time-exponent through mineral admixture is very effective to extension of service life in RC structure.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.73-81
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• 2012

Concrete structures are commonly exposed to freezing-thawing condition. This freezing-thawing action changes the pore structure of concrete, and it can reduce the durability of concrete. In this study, the change of the internal pore structure and durability of concrete due to freezing-thawing action are investigated. According to results, the excellent durability records were reported by the existing evaluation methods for all mixes. However, the pores, 50~100nm size in diameter, are increased in concrete specimens exposed to freezing-thawing action, and the chloride penetration resistance was significantly reduced. The linear relationship between pore structure and chloride penetration resistance was shown in water cured concrete. Meanwhile, the linear relationship was decreased when concrete is exposed to freezing-thawing condition. It is desirable to review the criterion of durability evaluation for concrete specimens exposed to freezing-fthawing and chloride attack condition, simultaneously.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.3
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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.