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Macrocyclic Complexes of Actinide and Lanthanide Metals (Ⅰ). Formation and Properties of Cation Complexes with Macrocyclic Ligands (악틴 및 란탄족금속의 거대고리 착물 (제 1 보). 거대고리 리간드의 금속착물의 형성과 성질)

  • Jeong, O Jin;Choe, Chil Nam;Yun, Seok Jin;Son, Yeon Su
    • Journal of the Korean Chemical Society
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    • v.34 no.2
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    • pp.143-158
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    • 1990
  • Metal complexes were prepared by reacting uranium (Ⅵ), thorium (Ⅳ) and rare earth metal (Ⅲ) ions including Nd (Ⅲ), Sm (Ⅲ) and Ho (Ⅲ) with macrocyclic ligands including five crown ethers, nine crownands and one cryptand ligands, and subjected to NMR studies in order to examine coordination sites of the ligands and compositions of the complexes formed. Among the marcocyclic ligands, crown ethers and crownand ligands have shown down-field shifts of the methylene protons of the lcigands by forming stable complexes with all the metal ions and the differences of chemical shifts were decreased as increasing of the cavity-size of crown ethers for the same metal ions and decreasing of the atomic number of the rare earth metals for the same ligands. It has been found that crownand 22 gave a stable complex with uranium(Ⅵ) ion by the coordination through both oxygen and nitrogen atoms of the ligand whereas no complex was formed with the rare earth metal(Ⅲ) ions, which on the other hand were found to form stable complexes with cryptand 221. The rest of the crowand ligands have also been found to form stable complexes with uranium(Ⅵ) ion by coordinating through all the oxygen and nitrogen atoms of the ligands whereas no complexes were formed with the rare earth metal(Ⅲ) ions. It has also been shown by 1H-NMR study that uranium(Ⅵ), thorium(Ⅳ) and rare earth metal(Ⅲ) ions formed 1:1 complexes with the macrocyclic ligands except for thorium(Ⅳ) complex of 12C4 in which the mole ratio of metal to ligand is 1:2. More stable metal complexes show larger changes in chemical shifts of the coordinated ligand protons. Finally, the rare earth metal(Ⅲ) complexes of 18C6 have shown ligand exchange reaction with the solvent molecules in acetylacetone solution, which was not observed for the uranium (Ⅵ) complexes.

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Antioxidant Effects and Improvement of Lipid Metabolism of Acanthopanacis cortex Water Extract in Rats Fed High Fat Diet (고지방 식이 흰쥐에서 오가피 추출물의 항산화 효과 및 지질 개선 효과)

  • Park, Young-Sook
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.1
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    • pp.37-45
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    • 2010
  • The effects of an Acanthopanacis cortex water extract on lipid levels, lipid peroxide, total antioxidant status and antioxidant enzyme activities were evaluated in rats fed one of the following diets for six weeks: normal diet and deionized water (ND), normal diet and Acanthopanacis cortex water extract (NDC), high fat diet and deionized water (HFD), high fat diet and Acanthopanacis cortex water extract (HFDC). The food intakes were significantly lower, but the food efficiency ratios were significantly higher in the high fat diet groups. The level of HDL-cholesterol in the plasma was significantly increased and the levels of LDL-cholesterol and triglyceride in the plasma were significantly decreased by the Acanthopanacis cortex water extract in the high fat diet groups. As a a result, the AI (atherogenic index) and CRF (cardiac risk factor) were significantly lower in the high fat diet groups that were treated with Acanthopanacis cortex water extract. The triglyceride and the total cholesterol of the liver were also significantly upregulated in the high fat diet groups, while the total cholesterol of the liver decreased in response to treatment with Acanthopanacis cortex water extract (HFDC). The plasma and liver concentrations of thiobarbituric acid reactive substances (TBARS) were significantly reduced by the addition of Acanthopanacis cortex water extract to the normal diet groups. The total antioxidant status (TAS) in the plasma was significantly upregulated by adding Acanthopanacis cortex water extract to the high fat diet groups. The activities of SOD, catalase and GST were also significantly higher in the Acanthopanacis cortex water extract groups when compared to the ionized water groups. The activity of GSH-Px and the concentration of GSH in the liver were significantly higher following the addition of Acanthopanacis cortex water extract to the high fat diet groups. Taken together, these results suggest that a supplementation of the diet of rats fed a high fat diet with Acanthopanacis cortex water extract improves lipid metabolism, reduces lipid peroxide and improves the activities of antioxidant enzymes, which may have favorable effects on antioxidant systems by improving the total antioxidant status (TAS).

Economic Injury Level of Mamestra brassicae L. (Lepidoptera: Noctuidae) on Early Stage of Cabbage (Brassica oleracea L. var capitata L.) (양배추에서 생육초기 도둑나방의 경제적피해수준 설정)

  • Kang, Taek-Jun;Jeon, Heung-Yong;Kim, Hyeong-Hwan;Yang, Chang-Yeol;Kim, Dong-Soon
    • Korean journal of applied entomology
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    • v.48 no.2
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    • pp.237-243
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    • 2009
  • This study was conducted to develop economic injury level (ElL) and economic threshold (ET) of Cabbage armyworm, Mamestra brassicae L. on cabbage (Brassica oleracea L. var). The changes of cabbage biomass and M. brassicae density were investigated after introduction of larval M. brassicae (2nd instar) at different densities: 0, 1, 2, 4, 8, and 16 larvae per plant at 40 d after planting for an open field experiment, and 0, 2, 5, 8 and 12 larvae per plant at 25 d after planting for a glass house experiment. In the field experiment, the yield loss of cabbage was not significantly different among treated-plots at 30 d after the larval introduction, showing an over-compensatory response of cabbage plants to M. brassicae attack. In the glasshouse experiment, however, the biomass of cabbage at 15 d after the larval introduction significantly decreased with increasing the initial introduced number of M. brassicae, resulting in 38.3, 36.7, 21.7, 23.3 and 16.7g in above treated-plots, respectively. The relationship between cumulative insect days (CID) and yield loss (%) of cabbage was well described by a nonlinear logistic equation. Using the estimated equation, ElL of M. brassicae on cabbage was estimated at 44 CID per plant based on the yield loss 14%, which take into account of an empirical gain threshold 5% and marketable rate 91% of cabbage. Also, ET was calculated at 80% of the EIL: 35 CID per plant. Until a more elaborate EIL-model is developed, the present result may be useful for M. brassicae management at early growth stage of cabbage.

Two stage reconstruction of bilateral alveolar cleft using Y-shaped anterior based tongue flap and iliac bone graft (Y-형 전방 기저 설 피판과 장골 이식을 이용한 양측성 치조열의 이단계 재건술)

  • Lee, Jong-Ho;Kim, Myung-Jin;Kang, Jin-Han;Kang, Na-Ra;Lee, Jong-Hwan;Choi, Won-Jae;Choi, Jin-Young
    • Korean Journal of Cleft Lip And Palate
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    • v.3 no.1
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    • pp.23-31
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    • 2000
  • Objective: When an alveolar cleft is too large to close with adjacent mucobuccal flaps or large secondary fistula following a primary bilateral palatoplasty exists, a one-stage procedure for bone grafting becomes challenging. In such a case, we used the tongue flap to repair the fistula and cleft alveolus in the first stage, and bone grafting to the cleft defect was performed in the second stage several months later. The purpose of this paper is to report our experiences with the use of an anteriorly-based Y-shaped tongue flap to fit the palatal and labial alveolar defects and the ultimate result of the bone graft. Patients: A series of 14 patients underwent surgery of this type from January 1994 to December 1998.The average age of the patients was 15.8 years old (range: 5 to 28 years old). The mean period of follow-up following the 2nd stage bone raft operation was 45.9 months (range: 9 to 68 months). In nine of the 14 cases, the long-fork type of a Yshaped tongue flap was used for extended coverage of the labial side alveolar defects with the palatal fistula in the remaining cases the short-forked design was used. Results: All cases demonstrated a good clinical result after the initial repair of cleft alveolus and palatal fistula. There was no fistula recurrence, although Partial necrosis of distal margin in long-forked tongue flap was occurred in one case. Furthermore, the bone graft, which was performed an average of 8 months after the tongue flap repair, was always successful. Occasionally, the transferred tongue tissue was bulging and interfering with the hygienic care of nearby teeth; however, these problems were able to be solved with proper contour-pasty performed afterwards. No donor site complications such as sensory disturbance, change in taste, limitations in tongue movement, normal speech impairments or tongue disfigurement were encountered. Conclusion: This two-stage reconstruction of a bilateral cleft alveolus using a Y-shaped tongue flap and iliac bone graft was very successful. It may be indicated for a bilateral cleft alveolus patient where the direct closure of the cleft defect with adjacent tissue or the buccal flap is not easy due to scarred fibrotic mucosa and/or accompanied residual palatal fistula.

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Current status, mechanism and control of herbicide resistant weeds in rice fields of Korea (한국 논에서 제초제 저항성잡초의 발생 현황, 메카니즘 및 방제)

  • Park, Tae Seon;Seong, Ki Yeong;Cho, Hyun Suk;Seo, Myung Chul;Kang, Hang Won;Park, Kee Woong
    • Korean Journal of Agricultural Science
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    • v.41 no.2
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    • pp.85-99
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    • 2014
  • Sulfonylurea (SU)-resistant weeds of eight annual weeds, Monochoria vaginalis, Scirpus juncoides and Cyperus difformis, etc., and four perennial weeds, Scirpus planiculmis, Sagittaria pigmaea, Eleocharis acicularis and Sagittaria trifolia as of 2013 since identification Monochoria korsakowii in the reclaimed rice field in 1998. And the resistant Echinochloa oryzoides to ACCase and ALS inhibitors has been confirmed in rice fields of the southern province, Korea in 2009. In the beginning, the M. vaginalis, S. juncoides and C. difformis of these SU-resistant weeds were rapidly and individually spreaded in different fields, however, these resistant weeds have been occurring simultaneously in the same filed recently. The resistant biotype by weed species demonstrated about 10-to 1,000-fold resistance, based on $GR_{50}$ values of the SU herbicides tested. And the resistant biotype of E. oryzoides to cyhalofop-butyl, pyriminobac-methyl, and penoxsulam was about 14, 8, and 11 times more resistant than the susceptible biotype base on $GR_{50}$ values. The products and applied area of SU-included herbicides have been increased rapidly, and have accounted for about 69% and 96% in Korea, respectively. In Korea, the main cause of SU-resistant weed is extensive use of these herbicides. The top ten herbicides by applied area were composed of all SU-included herbicides by 2003. The concentrated and successive treatment of ACCase and ALS inhibitors for control of barnyardgrass in rice led up to the resistance of E. oryzoides. Also, SU-herbicides like pyrazosulfuron-ethyl and imazosulfuron which effective to barnyardgrass can be bound up with the resistance of E. oryzoides. The ALS activity isolated from the resistant biotype of M. korsakowii to SU-herbicides tested was less sensitive than that of susceptible biotype. The concentration of herbicide required for 50% inhibition of ALS activity ($I_{50}$) of the SU-resistant M. korsakowii was 14-to 76-fold higher as compared to the susceptible biotype. No differences were observed in the rates of [$^{14}C$]bensulfuron uptake and translocation. Acetolactate synthase (ALS) genes from M. vaginalis resistant and susceptible biotypes against SU-herbicides revealed a single amino acid substitution of proline (CCT), at 197th position based on the M. korsakowii ALS sequence numbering, to serin (TCT) in conserved domain A of the gene. Carfentrazone-ethyl and pyrazolate were used mainly to control SU-resistant M. vaginalis by 2006 in Korea. However, the alternative herbicides such as benzobicyclone, to be possible to control simultaneously the several resistant weeds, have been developing and using broadly, because the several resistant weeds have been occurring simultaneously in the same fieled. The top ten herbicides by applied area in Korea have been occupied by products of 3-way mixture type including herbicides with alternative mode of action for the herbicide resistant weeds. Mefenacet, fentrazamide and cafenstrole had excellent controlling effects on the ACCase and ALS inhibitors resistant when they were applied within 2nd leaf stage.

Evaluation of the Surgical Treatment for Mitral Stenosis (승모판협착증의 외과적 치료에 대한 평가)

  • Sin, Dong-Geun;Kim, Min-Ho;Jo, Jung-Gu;Kim, Gong-Su
    • Journal of Chest Surgery
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    • v.29 no.10
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    • pp.1095-1101
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    • 1996
  • From July 1983 to June 1995, 95 consecutive patients with mitral stenosis were treated surgically in the Department of Thoracic and Cardiovascular Surgery, Chonbuk national University Hospital, mitral valve replacement(MVR) in 62 patients and open mitral commissurotomy(OMC) in 33 patients. Mitral stenosis combined with coronary artery disease, with aortic valve disease, or wish mitral valvular Insufficiency, were excluded from this study. Surgical procedures for mitral stenosis were evaluated, according to complication, reoperation, mor- tality, nd functional change at mid- and long-term postoperative period. Cardiothoracic ratio in the MVR group was greater than the OMC group(0.59 $\pm$0.07 in MVR, 0.53 $\pm$0. 07 in OMC, p<0.05), but other variables(age, sex, MYHA functional classification, EKG finding, echocardiographic finding) did not show significant difference between two groups in the preoperative periods. Even though pathologic valvular lesion(Sellor's pathologic type m: 35 in MVR, 13 in OMC) and valvular calcification(35 in MVR, 11 in OMC) were severe in the MVR group(p=0.001) at intraoperative observation, OMC was possible in 11 patients(23.9%) among 46 patients with valvular calcification and in 13 patients(27.1 %) among 61 patients with Sellor's pathologic type IH . There was no significant difference in early and late mortality, actuarial survival(75% in MVR, 87.6% in OMC at 12 year), but early and late hemorrhagic, thromboembolic complications in the MVR group were greater than in the OMC. Functional changes in NYHA functional classification, EKG lEnding, cardiothoraclc ratio, and echocardiographic finding(EF, LVIDS, LWDd, LAD) did not differ between two groups in mid- and long-term postoperative periods. We conclude that our efforts for preservation of the native valve would be continued, because hemorrhagic and thromboembolic complications in the MVR were greater than in the OMC, and OMC was possible even in patients with severely stenotic and calcified mitral valve, although there was no sis-nificant difference in the functional change, mortality, and survival between the M VR and OMC.

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Protective Effects of Korean Garlic Juice against the Toxicity of Methyl Mercuric Chloride (MMC) in Relation to Fetal Ossification in Pregnant Fischer-344 Rats (유기수은 노출로 인한 흰쥐 태자골격성장 지연에 대한 마늘의 보호효과)

  • Lee, Jin-Heon;Park, Kyung-Lyoul;Kim, Dae-Seon
    • Journal of Environmental Health Sciences
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    • v.34 no.2
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    • pp.161-169
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    • 2008
  • This study evaluates the protective effects of Korean garlic juice against the toxicity of methyl mercuric chloride (MMC) in relation to fetal ossification in pregnant Fischer 344 rats. This study has as its basis, both theory and data that neutral amino acids in garlic juice have protective effects against mercury poisoning. Pregnant rats were dosed in various combination with 20 mg MMC/kg body wt. and 0.5 or 1.0 garlic juice/kg body wt. on the 7th day of gestation. Fetuses were extracted from the dams on 20th day of gestation, and the fetal bones were stained and measured. The results obtained are as follows: 1. Fetal body weights, body lengths, and head length were significantly decreased by as much as 23.5%, 21.3%, 15.5% respectively in 20 mg/wt kg methyl mercuric chloride groups (p<0.05). But in the garlic treated groups, they were almost similar to the controls. 2. The ossification centers were significantly decreased by as much as 35.1% in pelvic phalanges, 53.5% in pectoral phalanges, 74.1% in ternebrae, 76.2% in tail in 20 mg/wt kg methyl mercuric chloride groups (p<0.05). But in the garlic treated groups, they were significantly increased by as much as $81.2{\sim}88.7%$ and $94.8{\sim}98.9%$ of controls. 3. The ossified pectoral girdles were significantly decreased by as much as 66.6% in clavicle, and in other areas $74.2{\sim}87.4%$ in the 20 mg/wt kg methyl mercuric chloride groups (p<0.05). But in the garlic treated groups, they were significantly increased by as much as $81.2{\sim}88.7%$ and $94.8{\sim}98.9%$ of the controls. 4. The ossified pelvic girdles were significantly decreased by as much as 57.1% and 56.1% in two ischium, $67.2{\sim}81.7%$ in metacarpals in the 20 mg/wt kg methyl mercuric chloride groups (p<0.05). But in the garlic treated groups, they were significantly increased by as much as $67.0{\sim}85.6%$ and $90.1{\sim}98.7%$ of the controls. 5. The ossified terenebrae were unchanged or significantly decreased; 0.0% in 5th, 54.1% in 1st, 83.9% in 2nd, 75.0% in 3rd, 72.7% in 4th, 79.8% in 6th of 20 mg/wt kg methyl mercuric chloride groups (p<0.05). But in the garlic treated groups, they were significantly increased by as much as $29.5{\sim}55.1%$ and $54.5{\sim}84.0%$ of the controls. 6. The ossified ribs were significantly decreased by as much as $8.3{\sim}18.0%$ in 20 mg/wt kg methyl mercuric chloride groups (p<0.05). But in the garlic treated groups, they were significantly increased by as much as $87.1{\sim}93.5%$ and $96.3{\sim}99.7%$ of the controls. In conclusion, Korean garlic juice significantly protected against the toxicity of MMC in relation to the fetal ossification in pregnant rats.

Study of Rainfall-Runoff Variation by Grid Size and Critical Area (격자크기와 임계면적에 따른 홍수유출특성 변화)

  • Ahn, Seung-Seop;Lee, Jeung-Seok;Jung, Do-Joon;Han, Ho-Chul
    • Journal of Environmental Science International
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    • v.16 no.4
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    • pp.523-532
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    • 2007
  • This study utilized the 1/25,000 topographic map of the upper area from the Geum-ho watermark located at the middle of Geum-ho river from the National Geographic Information Institute. For the analysis, first, the influence of the size of critical area to the hydro topographic factors was examined changing grid size to $10m{\times}10m,\;30m{\times}30m\;and\;50m{\times}50m$, and the critical area for the formation of a river to $0.01km^2{\sim}0.50km^2$. It is known from the examination result of watershed morphology according to the grid size that the smaller grid size, the better resolution and accuracy. And it is found, from the analysis result of the degree of the river according to the minimum critical area for each grid size, that the grid size does not affect on the degree of the river, and the number of rivers with 2nd and higher degree does not show remarkable difference while there is big difference in the number of 1st degree rivers. From the results above, it is thought that the critical area of $0.15km^2{\sim}0.20km^2$ is appropriate for formation of a river being irrelevant to the grid size in extraction of hydro topographic parameters that are used in the runoff analysis model using topographic maps. Therefore, the GIUH model applied analysis results by use of the river level difference law proposed in this study for the explanation on the outflow response-changing characters according to the decision of a critical value of a minimum level difference river, showed that, since an ogival occurrence time and an ogival flow volume are very significant in a flood occurrence in case of not undertow facilities, the researcher could obtain a good result for the forecast of river outflow when considering a convenient application of the model and an easy acquisition of data, so it's judged that this model is proper as an algorism for the decision of a critical value of a river basin.

Content Analysis of Life Science Area in Science Textbooks According to Korean Elementary Curriculum Change (한국 초등학교 교육과정 변천에 따른 과학 교과서 생명영역 내용분석)

  • Koh, Yeon-Sook;Kim, Hyo-Nam
    • Journal of The Korean Association For Science Education
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    • v.36 no.2
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    • pp.203-219
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    • 2016
  • The purpose of this paper was analyzing the contents of life science area in elementary science textbooks according to Korean science curricula change to get suggestions for the advancement of science curriculum. The framework of content analysis was developed by revising TIMSS 2015 life science evaluation framework. The results of this research were as follows: 'The differences of living things and non-living things appearing in the first grade mostly were not included in the 1st, the 6th and the 2009 revised curricula. Contents emphasizing rural life were appeared from 'Teaching themes period' to the 2nd curriculum period, disappeared from the 3rd curriculum period until the 2009 revised curriculum. Contagious disease was emphasized in all elementary grades in the 1st curriculum period, which reflected a social phenomena emphasizing health and hygiene after the Korean War. Mostly fungus was included until the 7th curriculum period and bacteria and virus were added from the 2007 revised curriculum period. The way of improving health was emphasized continuously.' The differences of living things and non-living things should be included in elementary science curriculum for the correct 'life' concept formation of elementary students. 'Strategies for helping the living of descendants' and 'the heredity of animal and plant' which were appeared in the lower grades, should be included at the higher grades with greater depth. The incoming elementary science textbooks also need to include science contents about evolution in greater depth, along with human health.

A Comparison Study on the Internet Addiction and Health Problems of Middle School Students between Urban and Rural Area (도농간 중학생의 인터넷 중독과 건강문제 비교연구)

  • Yeon, Mi-Jung;Kim, Keon-Yeop;Lee, Moo-Sik;Hong, Jee-Young;Bae, Seok-Hwan;Hwang, Hye-Jeong
    • Journal of the Korea Convergence Society
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    • v.1 no.1
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    • pp.41-47
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    • 2010
  • This study was conducted to investigate determinent factors of the internet addiction that have influenced on middle school students. We randomly selected each one middle school in urban and rural areas, and conducted survey in 862 students of 2nd and 3rd grade from September 1 to 15, 2005. By using a statistical program called SPSS10.0, the data collected thereby were analyzed through a series of statistical methods including $x^2$-test, logistic regression analysis. The result of logistic regression analysis showed that the significant variables in urban area were resting time and using time a day. In rural area, sex, economic level, resting time and using time a day were significant variables. Higher status of internet addiction showed significant relationship with physical problems, anxiety, maladjustment to school, insufficient sleep time, fatigue in eyes, headache, pain in neck or shoulder, chronic fatigue, reduced vision, weight reduction, indigestion, xeroderma and adjustment to school. Especially, resting time and using time a day have dominant influence on internet addiction. And in case that the groups who showed high addiction tendency, there were negative health problem by physical, mental and social problem. To prevent internet addiction health education programs of right internet use and time, importance of rest, and health problems must be considered in internet addiction prevention policy.