• Title/Summary/Keyword: Tissue concentration

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FINITE ELEMENT ANALYSIS OF STRESS DISTRIBUTION ACCORDING TO THE METHOD OF RESTORATION AFTER ROOT CANAL THERAPY (상악 중절치 근관치료후 수복 방법에 따른 응력 분포의 유한 요소 분석)

  • Lee, Jae-Young;Lee, Chung-Sik
    • Restorative Dentistry and Endodontics
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    • v.19 no.2
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    • pp.549-567
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    • 1994
  • Restoration of severly damaged teeth after endodontic treatment had been an interest to many dentists, and it is a fact that there have been lots of studies about it. In these days, although we have used Para-Post, pins, threaded steel post, cast gold post and core, and so on, as a method of restoration frequently, it has been in controversy with the influence of them on the teeth and surrounding periodontal tissue. In this study, we assume that the crown of the upper incisor have severly damaged, so, after the root canal therapy, 4 types of restoration had been carried out; 1) coronal-radicular amalgam restoration, 2) after setting up the Para-Post, restore with composite resin core only, 3) after setting up the Para-Post; restore with amalgam core, then cover with the PPM crown 4) after setting up the Para-Post, restore with composite core, then cover with the PPM crown. After restoration, in order to observe the concentration of stress at internal portion of the teeth and the sourrounding periodontal tissue, developing a 2-dimensional finite element model of labiopalatal section, then loading forces from 3 direction - direction of 45 degrees from lingual side near the incisal edge, horizontal direction from labial height of contour, vertical direction at the incisal edge-were applied. The analyzed results were as follows: 1. Stress of the normal central incisor was concentrated on the dentin aroundpulp chamber, labiocervical portion of a tooth and root apex, but with the alveolar bone, in the case of load from the direction of 45 degrees from lingual side near the incisal edge showed remarkable concentration of stress: 2. Coronal-radicular amalgam technique -showed less concentration of stress on the root and surrounding periodontal tissue than the restoration with the Para-Post. 3. The von Mises equivalent stress on the Para-Post showed maximum value at root-core junction rather than both ends and model with PPM restoration with amalgam core showed the least concentration of stress. Only the force from horizontal direction showed large shear stress on internal portion of the root, root apex and alveolar bone. 4. PPM crown with composite core rarely showed the concentration of stress on root and periodontal tissue. 5. As for alveolar bone, remarkable shear stress was concentrated on labial and palatal side by horizontal load.

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Enzyme Immunoassay for the Sulfamethazine Residues in Pork Tissue

  • Park, Jun-Hong;Lim, Yoon-Kyu
    • Journal of Food Hygiene and Safety
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    • v.11 no.4
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    • pp.287-290
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    • 1996
  • To control the maximum residue level (MRL) for sulfamethazine (SMZ) residues in pork tissue, a microbial inhibition method is a regulatory screening assay method in Korea. Microwell plate-based competitive enzyme immunoassay (ELISA) kit is avalable for routine screening of SMZ residues in pork tissue. One ELISA kit is evaluated. Phosphate buffer extracts of samples fortified with SMZ at 0, 1, 5, and 10 ng/g were used in a recovery test of the kit. Market pork samples were assayed by the kit. Recovery of sulfamethazine was 104% at 10 ng/g. Intraassay variations and interassay variations for the kit were 7.70% and 5.76%, respectively. Concentration causing 50% inhibition of color development compared with blanks was 16.4ng. The violative pork samples with over MRL (0.1 $\mu\textrm{g}$/g) was 4 of 32 cases (12.5%) by used ELISA kit. This result indicates a possibility of the ELISA kit for screening test of SMZ residues in pork tissue, and still needs a comfirmatory assay for mandatory purposes.

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Genotypic Responses to Cytokinin Requirements in Callus Culture of Korean Varieties of Phaseolus vulgaris L. (강남콩(Phaseolus vulgaris L.) 국내품종의 조직배양에서 유전자형에 따른 Cytokinin 요구성)

  • Kim, Sang-Gu
    • Journal of Plant Biology
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    • v.27 no.3
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    • pp.173-178
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    • 1984
  • Callus culture of Phaseolus vulgaris L. was carried out to examine the ability to grow on cytokinin-free medium. Of the sixteen cultivars of P. vulgaris, eight were classified as completely cytokinin-autonomous phenotype and five were found to be cytokinin-dependent phenotype. Intermediate phenotype was shown in three cultivars. Using cv. Palgong and ca 21 as cytokinin-dependent genotypes, the genotype responses to the cytokinin requirements of callus tissue were studied in detail. The callus tissue of cv. Palgong and ca 21 were never habituated in cytokinin-free medium, regardless tissue origin and cytokinin concentration in previous passages. The result suggests that cytokinin dependency of callus tissue of P. vulgaris cv. Palgong and ca 21 may be due to inactivation of cytokinin biosynthetic pathway.

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Sensitivity Changes of Auxin Transport System in Maize Coleoptile Segments

  • 윤인선
    • Journal of Plant Biology
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    • v.36 no.1
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    • pp.59-66
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    • 1993
  • In maize coleoptile segments where auxin transport capacity decreases with time following excision, susceptability of the tissue to transport inhibitors such as N-1-naphthylphthalamic acid (NPA), 3,4,5-triiodobenzoic acid (TIBA) or high concentrations of IAA was found to be rather increased. A time-dependent increase in the sensitivity to NPA can be postulated since the dose-response curve for NPA was shifted in the‘aged’tissue to the left (i.e. lower concentration). Preincubation of the tissue at a low temperature abolished the time-dependent sensitivity change, suggesting that cellular metabolism could be involved. The NPA-sensitive state was also brought about by calcium depletion of the tissue, which can be partially reversed by addition of calcium. Presence of exogenous IAA in the preincubation medium kept the auxin transport system from decay, implicating auxin as an endogenous controlling factor. Results of our experiments indicate a reversible, time-dependent changes of auxin transport system in which transport capacity and sensitivity to NPA are tightly coupled. Changes in the sensitivity to NPA were also seen in auxin action as well.

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Combined Effects of Iron and Zinc on Accumulation of Lead in Some Organs of Rats (아연(亞鉛)과 철분(鐵分) 동시투여(同時投與)가 백서(白鼠)의 장기내(臟器內) 연함량(鉛含量)에 미치는 영향(影響))

  • Ohm, Hyung-Taek;Song, Dong-Bin;Cha, Chul-Whan
    • Journal of Preventive Medicine and Public Health
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    • v.16 no.1
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    • pp.19-24
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    • 1983
  • In order to study the effects of iron and zinc on the lead poisoning of rats, lead with iron and zinc, or lead alone were administered orally to a total of 98 adult rats of Sprague-Dawley Species. The concentrations of lead, zinc, and iron were measured by atomic absorption spectrophotometer at every 20 days intervals of 20th, 40th, 60th, 80th and 120th day as a final measurement. Those datas were analysed and compared with those of control groups. The results were summarized as follows; 1. The concentration of lead in blood, bone. and liver tissues kept increasing in case of lead exposure group whereas it started decreasing at 60-80th day when concentration of zinc started increasing in case of combined exposure group. However, in kidney tissue, the concentration of lead in combined exposure group kept increasing up to the end of observation showing special high concentration at the final measurement at 120th day. 2. Concentration of zinc in blood and liver tissues had increased from 60-80th day in case of combined exposure group. 3. Concentration of iron in blood showed decreasing from $44.15{\pm}9.67\;to\;32.44{\pm}2.69{\mu}g/ml$ in case of lead exposure group, whereas it showed constant level of $47.50{\sim}45.65{\mu}g/ml$. However, in liver tissue it kept constant as control did from 40th to 60th days, but from 100th day on it started increasing to show much higher concentration than control.

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Effects of Hominis Placenta Pharmacopuncture Therapy on the Experimentally-induced Endometriosis in the Rats (자하거(紫河車) 약침(藥鍼)이 실험적으로 유발된 흰쥐의 자궁내막증에 미치는 영향)

  • Yoo, Yung-Ki;Kim, Hyung-Jun;Sin, Mi-Ran;Lee, Dong-Nyung
    • The Journal of Korean Obstetrics and Gynecology
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    • v.27 no.1
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    • pp.101-119
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    • 2014
  • Objectives: This study was performed to investigate the effects of Hominis Placenta pharmacopuncture (HPP) therapy on the experimentally-induced endometriosis in the rats. Materials and Methods: Endometriosis was induced in rats by autotransplanting uterine tissue to the peritoneum and divided them into three groups: (1) sham-operated group (n=8), (2) surgically induced endometriosis and untreated control group (n=8), (3) surgically induced endometriosis and HPP treated group. Sham-operated group and control group were inject with normal saline once a every other day for 30days, while treated group was injected with HPP extract once a every other day for same duration. Injected point of HPP and normal saline were subcutaneous tissue at Gwanwon (CV4) acupoint. Then we measured the body weight, the volume of endometriotic implants, the weigh of uterus and ovaries, and investigated the concentration of cytokines (MCP-1, TNF-${\alpha}$) in peritoneal fluids. Histopathology, immunohistochemisty for COX-2 and VEGF, and histochemistry for mast cell in transplanted uterine tissue were performed. Results: The volume ($mm^2$) of endometriotic implants in HPP treated group ($55.4{\pm}41.6$) was significantly decreased (p<0.01) compared with control group ($140{\pm}66.1$). And the concentration (pg/ml) of MCP-1 in peritoneal fluids in HPP treated group ($1117.6{\pm}60.5$) was significantly decreased (p<0.01) compared with control group ($1446.2{\pm}280.3$). The concentration (pg/ml) of TNF-${\alpha}$ in peritoneal fluids in HPP treated group ($80.6{\pm}31.4$) was decreased (p<0.01) compared with control group ($145.3{\pm}86.9$). Histopathologically, proliferation of endometriotic epithelia, infiltration of inflammatory cell and angiogenesis in transplanted uterine tissue of HPP treated group were weakly observed than those of control group. The COX-2 expression in endometrial, epithelial and stromal cells in transplanted uterine tissue of HPP treated group was decreased compared with control group. The VEGF expression of endometriotic epithelia, neovascular endothelia and stromal cell in transplanted uterine tissue of HPP treated group were weakly observed than those of control goup. Conclusions: HPP is effect on Endometriosis of rats by Experimentally-induced.

A study on Histologically Change of the Skin and Liver in Skin Burn (피부화상에 의한 피부 및 간의 조직학적 변화에 관한 연구)

  • Kim, Han-Soo;Kim, Sang-Soo;Kim, Yong-Kwon
    • Journal of Korean Physical Therapy Science
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    • v.8 no.1
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    • pp.923-934
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    • 2001
  • In order to investigate a pathogenesis of liver damage induced by skin burn, thermal injury was induced by scald burn on entirely dorsal surface in rats (total body surface area 30%) except for inhalated injury. At 5 and 24 h after scald bum, biochemical assay and morphological changes in skin tissue, serum and liver tissue were examined. The effects of bum injury on the levels of glutathione, lipid peroxide and on the activities of oxygen free radical generating and scavenging enzymes have been determined in association with observing of histologic and ultrastructural changes, measuring the protein concentration in plasma, and counting the number of intravascular polymorphonuclear leukocytes. The activity of xanthine oxidase, an enzyme of oxygen free radical generating system. was elevated (p<0.01) in serum, but not in skin and in liver tissue. Futhermore, thermal injury decreased not only the protein concentration in plasma but also the number of leukocytes, that indicates induction of edema formation with protein exudation and inflammation by neutrophil infiltration into the internal organs. These data suggest that acute dermal scald burn injury leads to liver damage, that is related to elevation of xanthine oxidase activity in serum. Xanthine oxidase may be a key role in the pathogenesis of liver damage induced by skin burn.

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Regulation of bone formation by high glucose in PDL cells

  • Jung, In-Ok;Zhang, Cheng-Gao;Kim, Sung-Jin
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2003.11a
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    • pp.80-80
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    • 2003
  • Insulin-dependent or Type 1 diabetes mellitus (IDDM) has been associated with an increased severity of periodontal disease. Since periodontal ligament (PDL) cells play a significant role in maintenance and regeneration of mineralized tissue, the success of procedures, such as guided tissue regeneration, is directly related to the ability of these cells to augment mineralized tissue. In this study, we investigated the time- and dose-dependent effect of high glucose on the proliferation and collagen synthesis of human periodontal ligament (PDL) cells. PDL cells were treated with high glucose (22mM, 33mM, 44mM) for 1 or 2 days. High glucose significantly inhibited proliferation of PDL cells as a time- and dose-dependent manner as evidenced by MTT assay. PDL cells were cultured in high glucose media (22mM, 33mM, 44mM) for 24 h. The ratio of collagen content to total protein was evaluated, and the gene expression of type I collagen was assessed by RT - PCR. The high concentration of glucose inhibited collagen synthesis, a marker of bone formation activity. This study indicated high glucose concentration could alter the metabolism of periodontal ligament cell, leading to alveolar bone destruction.

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Effect of Amino Acids on Oxygen Consumption of the Mang-Kong Frog (Gallula tornieri VOGT) Liver (맹꽁이 간의 산소소비량에 미치는 수종 아미노산의 영향)

  • 박상윤;최순영
    • The Korean Journal of Zoology
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    • v.4 no.2
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    • pp.20-24
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    • 1961
  • The present experiment was conducted to investigate the rate of oxygen consumption in relation to the several amino acids in the Mang-Kong frog ,Gallula tornieri VOGT. 1. When the liver tissue was suspended in the Ringer's solution (0.85% NaCl), the amount of oxygen consumption per hour was 0.043$\mu$l/mg , whereas when it was suspended in M/15, pH 5.8 phosphate buffer the oxygen consumption reached 0.93$\mu$l/mg. 2. When 0.5ml of 1% alanine and 0.5ml of 0.5% arginine were used as respiratory material the amount of oxygen consumption increased remarkably, while on the other hand glycine showed little influence on the amount of oxygen consumption. 3. When 0.5ml of 0.1% , 0.5% alanine-arginine mixture, 0.5ml of 0.1% , 0.5% alanine-glycine mixture and 0.5ml of 1 % arginine-glycine were added the oxygen consumption in the liver tissue increased somewhat in comparison to the case in which single amino acid was used. 4. Glycine appeared to have influence on the respiration of the liver tissue but the amount of oxygen consumption increased as the concentration of arginine-glycine mixture increased, whereas the rate of oxygen consumption increased remarkably as alaninie-glycine mixture decreased. It was evidenced that in the combination of alanine-arginine the rate of oxygen consumption increased as the concentration of the mixture decreased and vice versa.

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Salting of Chinese Cabbage under Sub-atmosphere (감압하에서 배추의 소금절임)

  • 정자림;김미정;김순동
    • Journal of the East Asian Society of Dietary Life
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    • v.3 no.2
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    • pp.99-106
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    • 1993
  • The aim of this study is to elevate the efficiency of salting with low salt concentration in order to improve the quality of salted Chinese cabbage. The efficiency of salting was tested with various sub-atmosphere(760mmHg to 0mmHg), temperature(20$^{\circ}C$ and 30$^{\circ}C$), and concentration of salt(3%, 5% and 10%). The salting efficiency was estimated by amounts of juice, calcium elution, sodium penetration and the state of tissue. The amunts of juice eleuted from Chinese cabbage was increased significantly with the decrease of atmosphere and the time to reach the highest amounts was reduced. This tendency was promoted, with increase of salinigy(from 3% to 10%)and the increase of temperature(more juice at 30$^{\circ}C$ than 20$^{\circ}C$). The amounts of eluted calcium from Chinese cabbage tissue during salting under sub-atmosphere was directly proportional to amounts of juice and was inversely proportional to penetrated sodium. The salting time was reduced with elevation of sub-atmosphere. It was desirable to take between 5.5 and 9 hours to salt under the condition of 3% of salting, 20$^{\circ}C$, and 560-0mmHg. It took between 4.4 and 5 hours under 5% of salt and between 4 and 4.5 hours under 10% of salt. However, it was undesirable because the drying phenomenon and the transparency of tissue appeared under 30$^{\circ}C$ and 160-0mmHg.

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