• Journal of Industrial Technology
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• v.14
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• pp.141-153
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• 1994

폴리이미드 분리막에 의한 $CCl_2F_2/Air$ 혼합물의 분리특성에 관하여 온도, 압력, stage cut(${\theta}$), 주입기체 조성등의 영향을 규명하였다. 본 연구의 실험범위 내에서 이상분리인자(ideal separation factor)는 600-200이었으며, glassy polymer인 폴리이미드 분리막에 대하여 투과도가 높은 air의 투과도는 $CCl_2F_2$ (dichlorodifluoromethane, CFC-12)에 의하여 상당히 감소함을 알 수 있었다. 그러나, 폴리이미드 분리막에 대한 투과도가 낮은 $CCl_2F_2$의 투과도는 air에 의하여 투과도가 증가하였다. 또한, 수학적 모델에 의한 예측치가 실험치와 잘 일치됨을 알 수 있었다.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.34 no.2
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• pp.233-249
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• 2023

This study aimed to understand the application and types of Creative Commons Licenses (CCL) in Korean journals and to increase understanding of the state of open access in South Korea. The study collected and analyzed CCL-related information from the websites of 2,097 KCI journals and compared the findings with DOAJ journals and previous research. The results of the study are summarized as follows. Firstly, 18% (377 journals) of the KCI journals adopted CCL, and among them, approximately 90% (337 journals) were in the field of STEM. There were few academic journals applying CCL in humanities and social sciences fields. Secondly, the types of CCL adopted by KCI journals were NC licenses (90%), with CC BY-NC (85%) being the most common. This is a significant difference from DOAJ journals, where 52% of academic journals applied CC BY or CC BY-SA. However, fewer journals applied licenses of the ND licenses than DOAJ journals and Spanish journals. Thirdly, 44% (167) of the 377 academic journals that applied CCL were simultaneously for free in public databases and sold for a fee in commercial databases. 33% (125) were publicly available for free in public databases, and 9% (33) were sold in commercial databases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1260-1265
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• 2001

This study was performed to investigate the protective effects of Hovenia dulcis Thunb on hepatotoxicity in carbon tetrachloride-intoxicated rats. Male Sprague-Dawley rats (220~240 g) were used as experimental groups, which were divided into 7 groups; Control group, $CCl_4$-treated group, hexane fraction pretreated and $CCl_4$-treated group, chloroform fraction pretreated and $CCl_4$-treated group, ethylacetate fraction pretreated and $CCl_4$-treated group, butanol fraction pretreated and $CCl_4$-treated group, $H_2O$ fraction pretreated and $CCl_4$-treated group. After 6 days, the activities of aminotransferase, contents of cholesterol, TG and hepatic lipid peroxide content in chloroform fraction pretreated and $CCl_4$-treated group were significantly decreased (p<0.05) compared to the only $CCl_4$-treated group. The content of glutathione and activities of GST in chloroform fraction pretreated and $CCl_4$-treated group were also significantly increased (p<0.05) compared to the only $CCl_4$-treated group. In addition, activities of SOD, catalase and GSH-Px in chloroform fraction pretreated and $CCl_4$-treated group were significantly decreased (p<0.05) compared to the only $CCl_4$-treated group. These results indicated that the chloroform fraction of Hovenia dulcis Thunb methanol extract showed hepatoprotective effect in carbon tetrachloride-intoxicated rats.

• Journal of Pharmacopuncture
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• v.2 no.1 s.2
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• pp.111-133
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• 1999

These studies were carried out to investigate the effect of Herbal-acupuncture with Inzinsammultang extract on the recovery from liver injury of rats. The liver injury of rats induced with 0.3ml/ea carbon tetrachloride. The Herbal-acupunture with Inzinsam multang extract solution inserted into corresponding focus of Kansu(BL18) in rats. In this study, SD-Rats(Sprague-Dawley) were divided into 4 groups ; Normal group (None treated group), Control-group(The group not treated after $CCI_4$-intoxication), Treated group; Example I-group(Saline-injected groups after $CCl_4$-intoxication) and Example II-group(Inzinsammultang-injected groups after $CCl_4$-intoxication). Through histological observation, Example II-group sho-ws that liver injury is weaker than Control group.(p<0.05) Biochemical assays for each serum enzyme activities of AST, ALT and LDH, levels of albumin, ${\gamma}$-GT, TG, total cholesterol were performed. The results were summarized as follows 1. AST(Aspartate aminotransferase) activity in serum significantly decreased in the Inzinsammultang-injected groups after $CCl_4$-intoxication. Inzinsammultang-injected groups after $CCl_4$-intoxication showed significantly higher AST activities, compared with the Saline-injected groups after $CCl_4$-intoxication.(p<0.05) 2. ALT(Alanine aminotransferase) activity in serum significantly decreased in the Inzinsammultang-injected groups after $CCl_4$-intoxication. The Inzinsammultang-injected groups after $CCl_4$-intoxication showed significantly higher AST activities, compared with the Saline-injected groups after $CCl_4$-intoxication(p<0.05) 3. Level of Albumin in serum significantly increased in the Inzinsarnmultang-injected groups after $CCl_4$-intoxication. 4. LDH(Lactate dehydrogenase) activities in serum significantly decreased in the Inzinsammultang-injected groups after $CCl_4$-intoxication.(p<0.05) 5. ${\gamma}$-GT(Glutamyl transferase) in serum significantly decreased in the Inzinsammultang-injected groups after $CCl_4$-intoxication(p<0.05) 6. As for the TG(Triglyceride) levels in serum, Inzinsammultang-injected groups after $CCl_4$-intoxication is no significant differences compared with the Saline-injected groups after $CCl_4$-intoxication.(p<0.05) 7. Total cholesterol in serum significantly increased in the Inzinsarnmultang-injected groups after $CCl_4$-intoxication.(p<0.05) Those results indicate that the Inzinsammultang Herbal-acupuncture have significant effects on the liver injury induced by $CCl_4$. So it is expected that the Inzinsammultang Herbal-acupuncture can be used to cure inflammations and recover the functions of damaged liver cells.

• Toxicological Research
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• v.11 no.2
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• pp.247-252
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• 1995

To evaluate the effect of xanthine oxidase on liver injury by $CCl_4$, liver damage was induced both in allopurinol pretreated rats (500 mg/kg. ip) and control group by twice intraperitoneal injection of $CCl_4$ (0.1 ml/100 g body wt. 50% in olive oil) at interval of one day. Increases in the levels of serum alanine aminotransferase and liver weight/body weight (%) by $CCl_4$ were significantly smaller inallopurinol pretreated rats than in control whereas the hepatic microsomal glucose-6-pholphatase activities were significantly higher in allopurinol pretreated rats than control group by $CCl_4$ treatment. These results indicates that allopurinol pretreatment may reduce the liver damage in $CCl_4$ intoxicated rats. In rats either with $CCl_4$or not, hepatic type O xanthine oxidase activities were significantly reduced by allopurinol pretreatment and the increasing rate of these enzymes to each control was remarkably lower in allopurinol pretreated rats than control. Liver cytosolic protein contents and aniline hydroxylase, aminopyrine demethylase activities were higher in allopurinol pretreated rats than coirol rats when animals were treated with $CCl_4$. On the other hand, neither allopurinol pretreated nor $CCl_4$ treatment caused any significant changes in hepatic superoxide dismutase and catalase activities. Hepatic glutathione contents were higher in $CCl_4$-treated rats than control, but no significant changes were found in both between the allopurinol treated rats and $CCl_4$-treated rats pretreated with allopurinol, and glutathione and glutathione S-transferase activities were significantly reduced in $CCl_4$-treated rats than control whereas these enzyme activities showed on significant change in both between allopurinel treated and $CCl_4$-treated rats pretreated with allopurinol. It is concluded that xanthine oxidase reaction system augment $CCl_4$ induced liver injury via even oxygen free radical system.

• Preventive Nutrition and Food Science
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• v.8 no.2
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• pp.130-136
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• 2003

The protective effects of onion extract (OE), onion powder extracted in ethanol for 2 days. on carbon tetrachloride ($CCl_4$)-induced hepatotoxicities and the possible mechanisms involved in this protection were investigated in mice. Pretreatment with OE prior to the administration of $CCl_4$ significantly reduced the increase in serum alanine and aspartate aminotransferase activities and hepatic lipid peroxidation in a dose-dependent manner. In addition, pretreatment with OE significantly prevented the depletion of reduced glutathione content in the liver of $CCl_4$-intoxicated mice. $CCl_4$-induced hepatotoxicity was also prevented, as indicated by a liver histopathologic findings. The effects of OE on the cytochrome P450 (P450) 2E1, the major isozyme involved in $CCl_4$ biotransformation were investigated. Treatment of mice with OE resulted in a significant decrease in P450 2E1-dependent p-nitrophenol and aniline hydroxylation in a dose-dependent manner. Consistent with these observations, the P450 2E1 expressions were also decreased, as determined by immunoblot analysis. OE also exhibited antioxidant effects in FeCl$_2$-ascorbate induced lipid peroxidation in rat liver homogenates and in superoxide radical scavenging activity. These results show that the protective effects of OE against the $CCl_4$-induced hepatotoxicity may be due to its ability to block bioactivation of $CCl_4$, mainly tty inhibiting the expression and activities of P450 2E1 and by scavenging free radicals.

• YAKHAK HOEJI
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• v.43 no.6
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• pp.827-833
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• 1999

In this study, we have investigated the effect of Biphenyl Dimethyl Dicarboxylate (DDB), a synthetic analogue of Schizandrin C isolated from Schizandrae Fructus on cytochrome $P_450$ lAl and 2Bl, and the protective mechanism against $CCl_4-induced$ hepatotoxicity in rat liver. After DDB was administered into male rats for different periods of time (1~7 days) and with different doses (25, 50, 100 and 200 mg/kg), mRNA levels of CYPlAl were measured by polymearse chain reaction (PCR) and assayed the activities of CYPlAl specific ethoxyresorufin-O-dealkylase (EROD) and CYP2Bl specific benzyloxyresorufin-O-dealkylase (BROD). DDB treatment resulted in increase in CYP2Bl mRNA level and BROD activity, whereas there was no change in CYPlAl mRNA level and EROD activity. This effect of DDB was time-and dose-dependent and reached maximal level by 3 day and 200 mg/kg treatment. In addition, rats were pre-treated with DDB at doses of 25, 50 or 100 mg/kg daily for 4 days, 3-hr after final treatment on the 4th day, $CCl_4$ 0.3ml/kg was intraperitonially injected into the rats to examine the effect of DDB on $CCl_4-induced$ hepatic injury. Serum levels of ALT and AST were determined and histopathological examination was done in rat liver. Furthermore, we have measured hepatic microsomal malondialdehyde(MDA) level, a parameter of lipid peroxidation. Based on serum ALT level and lipid peroxidation, pretreatment of DDB, 50 mg/kg appeared the most protective effect against $CCl_4-induced$ heapatotoxity. These results indicate that DDB stimulates CYP2Bl mRNA level and BROD activity in time and dose dependent manner and suggest that protective effect of DDB on $CCl_4-induced$ hepatotoxicity may be mediated through free radical scavenging.

• Toxicological Research
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• v.19 no.2
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• pp.105-114
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• 2003

TO evaluate an effect of cyclohexane treatment on the degree of liver damage, rats were induced liver damage with 10 or 17 times $CCl_4$ injection (0.1 m1/100 g body wt., 50% $CCl_4$ dis-solved in olive oil) at intervals of every other day. Cyclohexane (1.56 g/kg body wt., i.p.) was administrated to the animals at 48 hours after the last pretreatment of $CCl_4$ . Rats were sacrificed at 4 hours after injection of cyclohexane. On the basis of histopathological findings, liver weight/body weight (LW/ BW, %), activities of serum alanine aminotransferase (ALT), xanthine oxidase (XO) and akaline phosphatase (ALP), and contents of liver protein and manlondialdehyde (MDA), $CCl_4$ -pretreatment induced liver damage. And $CCl_4$ 17 times treated group showed more severe liver damage than $CCl_4$ 10 times treated group. Administration of one dose of cyclohexane to $CCl_4$ 10 times treated animals resulted in the enhanced liver damage; liver necrosis with proliferation of fibroblast and bile duct abnormality, and increase in hepatic MDA content and the activities of serum ALP and ALT, But the enhanced liver damage was not found in $CCl_4$ 17 times treated animals. Serum cyclohexanone concentrations at 4 or 8 hours after injection of cyclohexane were higher in all liver damaged groups than normal group and were somewhat higher In $CCl_4$ 17 times treated animals than $CCl_4$ 10 times treated ones. Among the oxygen free radical metabolizing enzymes, hepatic cytochrome P45O dependent aniline hydroxylase (CYPdAH) activity in cyclohexane metabolizing enzyme system was meaningfully increased by the injection of cyclohexane to the liver damaged rats, with increased Vmax and high affinity to aniline. LW/BW (%) and activities of serum XO and ALT were more significantly increased in liver damaged groups than normal group by administration of cyclohexanone. In conclusion, it is assumed that an enhancement of liver damage by injection of one dose of cyclohexane to liver damaged animals might be caused by oxygen free radicals and cyclohexanone.

• Journal of Environmental Health Sciences
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• v.29 no.2
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• pp.80-86
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• 2003

To evaluate the effect of cyclohexane(CH) treatment on the serum levels of glutathion S-transferase(GST) activity in liver damaged animals, damaged liver was induced with pretreatment of 50% $CCl_4$ dissolved in olive oil (0.1 m1/100g body weight) intraperitoneally 17 times every other day. To $CCl_4$-treated rats, CH (1.56 g/kg body weight, i.p) was injected once and then the animals were sacrificed at 4 hours after injection of CH. The $CCl_4$-treated animals were identified as severe liver damage on the basis of liver functional findings, 1,e, increased serum levels of alanine aminotransferase(ALT), alkaline phosphate(ALP) and xanthine oxidase(XO) activities. On the other hand, $CCl_4$-treated animals injected with CH once($CCl_4$-pretreated animals) showed more decreased serum levels of ALT and XO, and more increased those of ALP rather than $CCl_4$-treated animals. In case of comparing the GST with ALT activity in liver, both $CCl_4$-treated and pretreated animals showed similar changing pattern of enzyme actvity. Especially $CCl_4$-pretreated animals showed significantly increased serum level of GST actvity compared with the $CCl_4$-treated those, whereas those of ALT showed reversed tendency. In aspects of GST enzyme kinetics, $CCl_4$-pretreated animals showed higher Vmax of liver GST enzyme than $CCl_4$-treated animals. In conclusion, injection of CH to the liver damaged rats led to enhanced liver damage and more increased activity of serum GST which may be chiefly caused by the enzyme induction.

• Environmental Analysis Health and Toxicology
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• v.17 no.2
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• pp.161-174
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• 2002

To investigate effects of A. gmelini on the 14-day CCl$_4$induced hepatotoxicity, extracts were prepared in 3 ml saline at the dose of 5,000 mg/kg b.w. to administer orally once daily. Each concentration (5：5, 2：5 : 7.5, 1：9, CCl$_4$: olive oil v/v) of CCl$_4$was orally administered with 2.5 ml/kg b.w., During the experiment, halves of the rats were sacrificed every 7 day and hemanalysis was done. On the 7th day, hemanalysis showed following recovery values; AST 52.6∼61.4％, ALT 55.9∼86.1％, ALP 46.0∼70.9%, BUN 75.7∼100.0< ％, TBIL 55.2∼96.1％, TCHO 38.0∼63.7％, and TG 55.2∼96.0％. On the 14th day, recovery values of each treatment were GOT 37.7∼43.1％, GPT 19.8∼45.9％, ALP 58.1∼95.9％, BUN 57.6∼100.0< ％, TBIL 78.6∼100.0< ％, TCHO 56.9∼100.0< ％, and TG 10.0∼5l.2%. By histological examination of liver, hydropic degeneration, fatty change, lipid accumulation and necrosis were also recovered by administration of A. gmelini extract.