• The Korean Journal of Pharmacology
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• v.5 no.1
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• pp.57-64
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• 1969

Acetylsalicylic acid, administered intravenously in a dose of 120 mg+250 mg/h, markedly decreased the urinary excretion of sodium and chloride, and slightly depressed potassium excretion, so that the ratio of urinary concentrations of potassium to sodium increased after ASA. Osmolar and free water clearances also diminished during water diuresis, and free water reabsorption $(T^cH_2O)$ decreased after ASA during mannitol diuresis. Glomerular filtration rate and urine flow rate changed little. When infused directly into a renal artery, ASA exhibited identical action on both kidneys, indicating that the renotropic action is mediated by some endogenous humoral agents or by some metabolites of ASA. A dose of 100 mg i.v. of spironolactone, a aldosterone antagonist, slightly reversed the renal reflect when given during maximum action of ASA. Ethacrynic acid could display its full diuretic action unhindered during maximum ASA action. Above observations lead to the suggestion that acetylsalicylic acid might release aldosterone and the action on electrolyte excretion may be mediated by the mineralocorticoid.

• YAKHAK HOEJI
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• v.21 no.3
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• pp.115-117
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• 1977

In conclusion, all the results in present experiments seem to be quite consistent with the concept that the steroid exerts its vascular permeability - suppressive action through activating specific gene(s) to induce certain mRNA(s) and then to produce certain functional protein(s).

• Biomedical Science Letters
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• v.29 no.3
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• pp.103-108
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• 2023

Enhancers are cis-elements to regulate transcription of cell/tissue-specific genes in multicellular organisms. These elements locate in upstream or downstream regions of target genes and are found in a long distance up to 100 Kb in some cases. Transcription factors and coactivators bind to enhancers in a chromatin environment. Enhancers appear to facilitate the transcription of target genes by communicating with promoters and activating them. As transcription activation mechanism of enhancers, chromatin looping between enhancers and promoters, tracking of enhancer activity to promoters along the intervening regions, and movement of enhancers and promoters into transcription condensates have been suggested based on various molecular and cellular biology studies. These mechanisms are likely to act together rather than exclusive each other for gene transcription. Understanding of enhancer action mechanism may provide a way to regulate the transcription of cell/tissue-specific genes relating with aging or various diseases.

• Geomechanics and Engineering
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• v.13 no.6
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• pp.977-995
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• 2017

It is well accepted that rock failure mechanism influence the cutting efficiency and determination of optimum cutting parameters. In this paper, an attempt was made to research the factors that affect the failure mechanism based on discrete element method (DEM). The influences of cutting depth, hydrostatic pressure, cutting velocity, back rake angle and joint set on failure mechanism in rock-cutting are researched by PFC2D. The results show that: the ductile failure occurs at shallow cutting depths, the brittle failure occurs as the depth of cut increases beyond a threshold value. The mean cutting forces have a linear related to the cutting depth if the cutting action is dominated by the ductile mode, however, the mean cutting forces are deviate from the linear relationship while the cutting action is dominated by the brittle mode. The failure mechanism changes from brittle mode with larger chips under atmospheric conditions, to ductile mode with crushed chips under hydrostatic conditions. As the cutting velocity increases, a grow number of micro-cracks are initiated around the cutter and the volume of the chipped fragmentation is decreasing correspondingly. The crack initiates and propagates parallel to the free surface with a smaller rake angle, but with the rake angle increases, the direction of crack initiation and propagation is changed to towards the intact rock. The existence of joint set have significant influence on crack initiation and propagation, it makes the crack prone to propagate along the joint.

• Herbal Formula Science
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• v.30 no.4
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• pp.293-304
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• 2022

Objectives : Sagunja-Tang is a famous prescription used in Korean medicine for the purpose of promoting vital energy, and there are few studies using Sagunja-Tang on cerebrovascular diseases yet. As previous studies confirmed that Sagunja-tang is highly likely to be used effectively for stroke, this study was intended to predict the mechanism through which Sagunja-tang would act effectively on stroke. Methods : In this study, a network pharmacology analysis method was used, and oral bioavailability (OB), drug likeness (DL), Caco-2 and BBB permeability were utilized to select compounds with potential activity. For the values of each variable used in this study, OB ≥ 30%, DL ≥ 0.18, Caco-2 ≥ 0, and BBB ≥ 0.3 were applied. Using the above variables, the relations between target genes and diseases that are presumed to be involved in the selected bioavailable compounds were constructed in a network format, and proteins thought to play a major role were identified. Results : Among the compounds included in Sagunja-Tang, 26 bioavailable compounds were selected and it was confirmed that these compounds can be effectively used in cerebrovascular diseases such as Alzheimer's disease and stroke. These compounds are considered to act on proteins related in cell death and growth. The most important mechanism of action was predicted to be apoptosis, and the protein that is thought to play the most key action in this mechanism was caspase-3. Conclusions : In our future study, Sagunja-Tang will be used in an ischemic stroke mouse model, and the mechanism of action will be explored focusing on apoptosis and cell proliferation.

• The Korean Journal of Pharmacology
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• v.3 no.1
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• pp.31-41
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• 1967

The author studied the hemolytic action of chlorpromazine on rabbit erythrocytes and obtained the following results: 1. Chlorpromazine caused hemolysis in vitro. The hemolytic action of chlorpromazine was milder than that of saponin(Colleman and Bell Co ) 2. Cholesterol had no marked effect on chlorpromazine hemolysis. 3. Dextrose, albumin and blood plasma protected erythrocytes against chlorpromazine hemolysis. 4. The mechanism of chlorpromazine hemolysis seemed to be different from that of saponin hemolysis. 5. Chlorpromazine increased tile osmotic fragility of rabbit erythrocytes. 6. The intravenous injection of chlorpromazine caused hemolysis in vivo.

• YAKHAK HOEJI
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• v.19 no.4
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• pp.227-233
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• 1975

The diuretic action of guanethidine was investigated in the dogs by means of the stop-flow technique. Guanethidine increased the rejection of sodium in the ascending limb of Henle's loop, as well as in the proximal and distal tubules, resulting in the decrease of the concentrating ability of the kidney, in marked natriuresis and diuresis. It was also effective during an osomotic diuresis, which was induced by infusing 10% mannitol can exhibit its effect even under the diuretic action of mercurophylline, suggesting a different mechanism from that of mercuric iuretics.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.178-185
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• 1999

Six of scaled concrete circular columns were experimentally investigated for the contribution of arch action to the column lateral resistance. For this the specimens with the variation of tranverse hoop steel spacing were tested in absence of axial loading All specimens showed the flexure governing behavior pattern irrelevant to transverse hoop spacing. This indicates that the role of arch action should be understood as the intermediate mechanism causing the interaction between shear and flexural mechanisms A simple truss model was proposed to qualitatively explain this notation but further study is needed to advance its application to general columns.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.03a
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• pp.261-264
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• 1997

A single action press robot, which consists of a driving unit, rotator, up-down feed base and feed bar, is developed and applied for the press automation. The driving unit is made up with a face cam and blade cam, which have a phase angle. The feeding system consists of a double speed-up apparatus and linear motion guides, and has a fast motion characteristics. A horizontal feeding speed of the feed bar is increased twice by the double speed-up apparatus. The driving mechanism could be simplified due to the speed-up of the feeding unit.

• The Korean Journal of Pharmacology
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• v.12 no.2 s.20
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• pp.61-65
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• 1976

Coptis rhizoma had been applied in the chines medicine as well as in the folk remidies and it was advocated that coptis rhizoma exerts good therapeutic effect in some case of alimentary disorders and other hypotensive ailments. However the basic pharmacology and the mechanism of hypotensive action are not clear. This experiment was carried out in order to reevaluate the pharmacology, especially hypotensive action of coptis rhizoma and to clarify the mechanism of action, in the rabbits and also $LD_{50}$ of coptis rhizoma was determined using mice as experimental animals. The results of the experiment were as follows. 1) $LD_{50}$ to the mice was 69 mg/kg. 2) Blood pressure manifested gradual responses by the fall of -17, -26, -62 mmHg in proportion to the administration of 3, 5, 10 mg/kg of coptis rhizoma extract respectively. 3) No significant differance was observed in heart rate between the normal control group and the coptis rhizoma extract treated group. 4) Administration of coptis rhizoma extract 5 mg/kg to the rabbit pretreated with atropine or avil did not show any significant difference in the blood pressure compared with that of control group. 5) In the rabbit pretreated with coptis rhizoma extract 5mg/kg, the hypotensive effect of epinephrine was significantly inhibited in comparison with that of normal rabbit.