• Tribology and Lubricants
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• 제39권4호
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• pp.148-153
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• 2023

Laser surface dimple patterning is a method of laser surface texturing to reduce lubrication sliding friction. The dimple pattern improves friction properties by reserving lubricant and trapping worn particles. This surface texturing technology can reduce coefficients of friction and extend the service life by applying a uniform load to the surface of the material. This study investigates the friction properties using PMMA, a highly compatible polymer material, as a specimen. We observe the friction properties of untextured specimens by processing specimens with dimple pattern densities of 5 and 10 on the surface area using laser. Dimple pattern density affects the coefficient of friction. We present the following friction property results using a pin-on-disc sliding friction test under saline lubrication. The coefficients of friction for the dimple patterned specimens are lower than those for the untextured specimens. As the normal load and sliding speed increase, the coefficients of friction of the dimple pattern specimens decrease differently from those of the untextured specimens. The specimen with a dimple pattern density of 5 at a normal load of 24.5 N and a sliding speed of 0.22 m/s has the best friction properties. Notably, different friction properties are exhibited depending on the dimple pattern densities.

• 대한한방내과학회지
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• 제30권1호
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• pp.107-118
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• 2009

Objectives : This study was aimed to investigated the effect of Yijin-tang on gastric motility and its mechanism of action in normal intact and partial pyloric obstructed rats. Methods : Gastric emptying was measured by the number of glass beads expelled from the stomach (containing one hundred of glass beads. ${\phi}1mm$) in 1 hour or 2 hours after glass beads and test drugs (normal saline. Yijin-tang 90mg/kg. Yijin-tang 270mg/kg) administration in normal intact and partial pyloric obstructed rats. In another series of experiments to evaluate the mechanism of Yijin-tang 270mg/kg under delayed conditions, normal intact rats were treated with atropine sulfate (1mg/kg,s.c.), cisplatin (10mg/kg,i.p.), quinpirole HCI (0.3mg/kg,i.p.) and NAME (NG-nitro-L-arginine methyl ester. 75mg/ kg,s.c.), respectively. Partial pyloric obstructed rats were modified by wrapping the nonabsorbable rubber ring (D :6mm, W:4mm, T: 1mm) around the 1st portion of the duodenum for 8 weeks. The myoelectrical activity of the gastric smooth muscle was recorded by a bipolar electrode placed at the abdominal surface in normal intact and partial pyloric obstructed rats. The gastric myoelectrical activity was measured for 30 minutes before and after orogastric administration of each solution (normal saline, Yijin-tang 270mg/kg) and expressed as dominant frequency, percent of normogastria and power ratio. Results : Yijin-tang improved gastric emptying more than normal saline in normal intact(p<0.001) and partial pyloric obstructed rats(p=0.002). Under the delayed gastric emptying induced by atropine sulfate, cisplatin, quinpirole HCI and NAME. Yijin-tang enhanced gastric emptying significantly in the cisplatin treated group(p<0.001). but didn't in other treated groups. Administration of Yijin-tang 270mg/kg has no significant effect on the myoelectrical activity of the gastric smooth muscle in both normal intact rats and partial pyloric obstructed rats. Conclusions : Yijin-tang seems to stimulate the gastric motility through suppressing the 5HT3 receptor and promoting the antroduodenal flow. We expect that Yijin-tang would be effective especially in dysmotility-like functional dyspepsia with partial pyloric obstruction or the side effects of cisplatin such as nausea, vomiting, abdominal discomfort, and delay of gastric emptying.

• Journal of Magnetics
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• 제20권3호
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• pp.302-307
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• 2015

The purpose of the study was to identify how isotope and magnetic resonance imaging (MRI) contrast media impact on noise to computed tomography (CT) examination. For the study, divide the phantoms to two groups: 1) saline, saline + different kinds of contrast agent without $^{99m}Tc$ administration; 2) $^{99m}Tc$ administration: saline, saline + different kinds of contrast agent with $^{99m}Tc$ administration. CT contrast agent was used for Iopamidol$^{(R)}$ and Dotarem. And MRI contrast agent was used for Primovist$^{(R)}$ and Gadovist$^{(R)}$. To obtain an image, we used CT scanner. With an obtained image, we set the $1cm^2$ region of interest in the middle of bottle to measure the noise and CT number. As a result, there was no difference in CT number before and after inserting $^{99m}Tc$ into all contrast media including Normal Saline. However, when it comes to Noise, there was a difference before and after inserting $^{99m}Tc$ into every contrast media except MRI contrast media such as Primovist$^{(R)}$ and Gadovist$^{(R)}$.

• Journal of Acupuncture Research
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• 제33권1호
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• pp.23-36
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• 2016

Objectives : The aim of this study was to investigate the asthma-suppressive and immuno-regulatory effect of AHCR-HA (Root of Asarum sieboldii Miq. water extract) on OVA (ovalbumin)-induced asthma in mice. Methods : All C57BL/6 mice experimental groups, except the Normal and N-AHCR groups, were sensitized with OVA. The mice in the N-AHCR group and the OVA-AHCR group were treated with water extract of AHCR (1 %) by an oral administration, and the OVA-Saline group were treated with saline solution. Oral dosesof AHCR water extract and saline were administered for 8 weeks, three times a week. Results & Conclusion : The lung weight and total cells in the lungs of the OVA-AHCR group decreased significantly compared with those of the OVA-Saline group. Total leukocytes and eosinophils in BALF and photomicrographs of the OVA-AHCR group decreased significantly compared with those of the OVA-Saline group. The collagen accumulation in the lung sections of the OVA-AHCR group decreased significantly compared with those of the OVA-Saline group. The concentrations of IL-4, IL-5, IL-13 and IgE in BALF and the serum of the OVA-AHCR group decreased significantly compared with those of the OVA-Saline group. The mRNA expressions of $TNF-{\alpha}$, $IL-1{\beta}$, IL-4, IL-5 and IL-13 in the lungs of the OVA-AHCR group decreased significantly compared with those of the OVA-Saline group.

• 대한약침학회지
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• 제12권3호
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• pp.31-40
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• 2009

Objective : This study was to investigate the effects of distilled Cervi Pantotrichum Cornu Pharmacopuncture and Zizyphi Spinosi Semen Pharmacopuncture on autonomic nervous system with Heart Rate Variability(HRV). Purpose of the trial was to observe what influence distilled Cervi Pantotrichum Cornu Pharmacopuncture and Zizyphi Spinosi Semen Pharmacopuncture have on the autonomic nervous system. Methods : 60 healthy male volunteers were divided into three groups which consist of two experimental groups such as Cervi Pantotrichum Cornu Pharmacopuncture and Zizyphi Spinosi Semen Pharmacopuncture, and a control group. Study design was a randomized, placebo-controlled, double-blind clinical trial. 20 subjects in experimental group were injected distilled Cervi Pantotrichum Cornu Pharmacopuncture at $GB_{21}$(Kyonjong), 20 subjects in other experimental group were injected distilled Zizyphi Spinosi Semen Pharmacopuncture and 20 subjects in control group were injected Normal Saline at $GB_{21}$(Kyonjong). One volunteer of each groups were excluded from analysis because of error during measuring HRV. At the end of the study 57 volunteers completed HRV analysis. HRV was measured by QECG-3:LXC3203(LAXTHA Inc. Korea) at P0, P1, P2, P3, P4, P5 and P6 and its time-course dependent change in each group was analyzed using paired t-test, and the difference of HRV fluctuation among two experimental group and a control was evaluated by one way ANOVA(p<0.05). Results : A. Time Domain Analysis 1. Analysis of Mean HRV, SDNN and Complexity After injection of distilled Cervi Pantotrichum Cornu Pharmacopuncture, Mean HRV was significantly decreased only at 20 minutes after injection. SDNN was significantly increased from 15 minute after injection. Complexity was significantly decreased only at 15 minute after injection. After injection of distilled Zizyphi Spinosi Semen Pharmacopuncture, Complexity was significantly decreased at 10, 15 and 30 minutes after injection. 2. Analysis of HRV index, pNN50 After injection of distilled Cervi Pantotrichum Cornu Pharmacopuncture, pNN50 was significantly decreased at 15, 20 and 25 minutes after injection. Compared with Normal Saline injection, distilled Cervi Pantotrichum Cornu Pharmacopuncture and Zizyphi Spinosi Semen Pharmacopuncture showed significant difference on HRV index and pNN50 at 5 minutes after injection. B. Frequency Domain Analysis 1. Analysis of Ln(TP), Ln(VLF) After injection of distilled Cervi Pantotrichum Cornu Pharmacopuncture, Ln(TP) was significantly increased at 15 and 30 minutes after injection. Ln(VLF) was significantly increased at 10, 15 and 30 minutes after injection. After injection of distilled Zizyphi Spinosi Semen Pharmacopuncture, Ln(VLF) was significantly increased only at 30 minutes after injection. Compared with Normal Saline injection, distilled Cervi Pantotrichum Cornu Pharmacopuncture showed significant difference on Ln(TP) after 5 minutes of injection. Conclusions : Our results suggest that Cervi Pantotrichum Cornu Pharmacopuncture and Zizyphi Spinosi Semen Pharmacopuncture in healthy adult man tend to activate the autonomic nervous system and sympathetic nervous system compared to Normal Saline within normal range.

• Restorative Dentistry and Endodontics
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• 제15권1호
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• pp.187-200
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• 1990

The purpose of this study was to investigate antimicrobial effect of several irrigation solutions on 7 anaerobes and 2 aerobes, which are found frequently in infected root canals. The antimicrobial effects of normal saline, 3% $H_2O_2$, 0.5% & 3.5% NaOCl, 10% & 50% citric acid and mixed solutions of 3% $H_2O_2$ plus 3.5% NaOCl were compared. No. 80 paper points dipped in bacterial broth were soaked in each irrigation solutions and moved into thioglycolate broth, subcultured in agar plate for bacterial growth. The results were as follows: 1. Normal saline had no antimicrobial effect. 2. Mixed solutions of 3% $H_2O_2$ plus 3.5% NaOCl, 10% citric acid had relatively weak antimicrobial effect. 3.3% $H_2O_2$, 50% citric acid, 0.5% NaOCl showed relatively strong antimicrobial effect. 4. 3.5% NaOCl had the strongest antimicrobial effect among used 7 irrigation solutions.

• Archives of Pharmacal Research
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• 제20권2호
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• pp.171-175
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• 1997

The stability of ondansetron and fluconazole in 5% dextrose injection and normal saline during simulated Y-site injection at room temperature was studied. Ondansetron 0.03, 0.1 and 0.3 mg/ml were admixed 1:1 with fluconazole 2 mg/ml. The solutions were stored at room temperature and samples were retrieved at time 0, 1, 2, 4 and 12 hr for immediate assay. At the time of the assay and before any dilution, each sample was visually inspected for clarity, color, precipitation, and the pH was determined. Drug concentrations were measured by a stability-indicating high performance liquid chromatograph. Ondansetron 0.03, 0.1 and 0.3 mg/ml were stable when mixed with concentration of fluconazole 2 mg/ml. There were no change in clarity and color and no precipitates in any admixture for 12 hr of inspection. The pH measurements did not have a particular trend in any direction over time.

• 대한한의학회지
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• 제38권1호
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• pp.34-45
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• 2017

Objectives: This study aimed to investigate the effect of banhasasim-tang intravenous herbal acupuncture (BST-IVHA) on emesis induced by chemotherapy in rats. Methods: This study used methotrexate(MTX)-induced Rat-Pica model. The rats were randomly allocated into seven groups; normal group, two saline groups, four Banhasasim-tang(BST) groups (groups treated with BST-IVHA). All the experimental animals except those in the normal group were injected with MTX. Those in the pre-treatment groups were treated with saline injection (saline group) or BST-IVHA (BST group) before MTX injection. Those in the post-treatment groups were treated with saline injection or BST-IVHA after MTX injection. Two different dosages of BST-IVHA solution (low dose; BST-1 group, high dose; BST-2 group) were used. The changes in body weight, food intake, and kaolin consumption at 24h, 48h, and 60h were monitored and analyzed. Results: 1. No significant change was found in body weight. 2. The food intake at 48h was increased significantly in the BST-1 pre-treatment group($19.89{\pm}0.01g$) compared to the pre-saline group($18.68{\pm}0.26g$). 3. The kaolin consumption was significantly decreased in the BST-1 pre-treatment group at 24h($0.24{\pm}0.02g$) and 60h($0.36{\pm}0.14g$), in the BST-2 pre-treatment group at 48h($0.02{\pm}0.01g$) and 60h($0.80{\pm}0.31g$) compared to the pre-saline group($24h:0.81{\pm}0.37g$, $48h:0.76{\pm}0.43g$, $60h:1.56{\pm}0.03g$). The kaolin consumption was also significantly decreased in the in the BST-1 post-treatment group at 24h($0.05{\pm}0.02g$), 48h($0.64{\pm}0.06g$) and 60h($0.14{\pm}0.05g$), in the BST-2 post-treatment group at 48h($0.01{\pm}0.01g$) and 60h($0.01{\pm}0.01g$) compared to the post-saline group($24h:0.51{\pm}0.4g$, $48h:3.58{\pm}0.33g$, $60h:2.5{\pm}0.2g$). Conclusions: BST-IVHA showed an anti-emetic effect in MTX-induced rat-pica model. This result suggests that BST-IVHA could be an effective treatment for chemotherapy-induced emesis.

• 대한한의학회지
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• 제34권3호
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• pp.25-36
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• 2013

Objectives: The purpose of this study was to investigate the effects of Zeae Stigma herbal-acupuncture (ZS-HA) at KI10 (Umgok) on nephritis induced by lipopolysaccharide (LPS) in rats. Methods: Rats were assigned to five groups, normal, LPS, NP, saline and ZS-HA. Rats in NP, saline, and ZS-HA groups were treated with needle prick, saline injection, and ZS-HA respectively at KI10, three times a week. All animals except the normal group were injected intra-peritoneally with LPS to induce nephritis. RBC and WBC, neutrophils in blood, TNF-alpha, CINC-1, creatinine in serum, urinal volume, total protein and creatinine in urine, and renal MPO were analyzed. Results: Needle prick at KI10 significantly reduced WBC in blood and CINC-1 in serum of LPS-stimulated rats. Saline injection at KI10 significantly reduced TNF-${\alpha}$ in serum and total protein in urine of LPS-stimulated rats. ZS-HA at KI10 significantly increased RBC in blood, and significantly reduced neutrophils in blood, TNF-${\alpha}$ in serum, and total protein in urine of LPS-stimulated rats. Conclusions: According to these results, it is postulated that ZS-HA at KI10 has anti-inflammatory and renal-protective effects on LPS-induced nephritis in rats, and both acupoint KI10 and herb Zeae Stigma made contributions to this effect. Further studies on the interaction between acupoint KI10 and herb Zeae Stigma may be needed.

• Journal of Acupuncture Research
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• 제32권3호
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• pp.15-25
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• 2015

Objectives : The purpose of this study is to investigate the effects of Pyrrosiae Herba herbal-acupuncture(PH-HA) at $KI_{10}$(Umgok) on nephritis induced by lipopolysaccharide(LPS) in rats. Methods : Rats were assigned to four groups: normal, LPS, saline and PH-HA. Rats in the saline and PH-HA groups were treated with saline injection and PH-HA respectively at $KI_{10}$, three times over the period of one week. All animals, except those in the normal group, were injected intra-peritoneally with LPS to induce nephritis. WBC, in blood, tumor necrosis factor alpha(TNF-${\alpha}$), cytokine-induced neutrophil chemoattractant 1(CINC-1), blood urea nitrogen(BUN), creatinine in serum, urinal volume, total protein creatinine in urine, and renal myeloperoxidase (MPO) were analyzed. Results : 1. PH-HA group showed significantly reduced levels of serum BUN, serum creatinine, TNF-${\alpha}$, and CINC-1 compared to the LPS group. Furthermore, a significant increase in urine output and more significant decreases in total protein in urine and MPO in renal tissue were observed in the PH-HA group when compared to the LPS group. 2. The PH-HA group showed significantly reduced levels of serum creatinine and renal MPO, and a more significant increase in urine output compared to the saline group. Conclusions : According to these results, it is postulated that PH-HA at $KI_{10}$ has anti-inflammatory and renal-protective effects on LPS-induced nephritis in rats, and both acupoint $KI_{10}$ and the herb Pyrrosiae Herba made contributions to these effects. Further studies on the interaction between acupoint $KI_{10}$ and the herb Pyrrosiae Herba may be needed.