• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.228-234
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• 2015

Using either the apical or axillary bud of the endangered species Abeliophyllum distichum Nakai, we tested the effect of bud position and culture method on shoot proliferation and rooting. In shoot proliferation, the axillary bud explant was more effective than the apical bud and the effect was fostered by BA treatment, whereas no differences were observed in shoot elongation by the explant position. Spontaneous rooting was observed in the MS basal medium and resulted in conspicuous differences in the explant position : more than 80% in apical bud explant and 28% in axillary bud explant was achieved, respectively. The positional effects were also observed in BA pre-treatments: generally vertical culture method appeared to be better in shoot proliferation, growth, and rooting than that of the horizontal culture method regardless of the BA pre-treatment duration. The highest shoot multiplication was achieved through the vertical culture method with axillary bud explant, whereas the best shoot elongation and rooting was obtained using the vertical culture method with the apical bud explant. Apical bud explant was superior to axillary bud explant in ex vitro micro-cuttings and revealed a significant difference in shoot growth and root development. The above results suggest that explant position and culture method influence the efficiency of micropropagation for a rare and endangered plant Abeliophyllum distichum.

• Korean Journal of Plant Tissue Culture
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• v.21 no.3
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• pp.173-176
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• 1994

Stem and petiol explants of peony culture turned to brownish black soon after placing onto medium and degenerated to death. Disroloration was caused mainly by ferrous and calcium cloride. Nitrate was a main factor for the death of culture. The culture damage was increased with the increment of the medium salt strength. A few latent axillary buds were elongated to shoots without forming callus.

• Applied Microscopy
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• v.35 no.1
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• pp.31-39
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• 2005

Synapses are contact points where one neuron communicates with another. The morphological change of synapses under various physiological or pathological conditions has long been hypothesized to modify their functional properties. 3-dimensional (3-D) reconstruction of synapses with serial ultrathin sections has contributed to the understanding of ultrastructural dimensions and compositions of synapses. The 3-D reconstruction procedures, however, require a great amount of expertise as well as include prohibitively timeconsuming processes. Here, we introduce efficient 3-D reconstruction technique using high-voltage electron microscopy (HVEM). Primarily, we established an optimal section thickness and staining condition to observe synaptic structures in detail under HVEM. The result showed that synaptic profiles were preserved at the section thickness of 250 nm without the overlapping of synaptic ultrastructures. An increase in the reaction time of en bloc staining was most efficient to enhance contrast than the extension of postembedding staining or the addition of uranyl acetate during dehydration. Then, 3-D reconstruction of parallel fiber-Purkinje cell synapses in the rat cerebellum was carried out with serial HVEM images and reconstruction software. The images were aligned and the contours of synapses were outlined on each section. 3-D synapses were finally extracted from the section files by grouping all the synaptic contours. The reconstructed synapse model clearly demonstrated the configuration of pre and postsynaptic components. These results suggest that 3-D reconstruction of synapses using HVEM is much efficient and suitable for massive quantitative studies on synaptic connectivity than conventional TEM approach using numerous ultrathin sections.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.351-358
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• 2016

Consistent with a previous study on the brown planthopper Nilaparvata lugens (BPH) (Seo et al., 2009), we identified seven distinct EPG waveforms (np, L1, L2, L3, L4-a, L4-b, and L5) in adult female Laodelphax striatellus (SBPH) that fed on rice plants, by using the direct current electrical penetration graph (DC-EPG) system. The shape of waveforms and the pattern of occurrence of each waveform of SBPH were very similar to those of BPH. L3 and L4-a always occurred prior to L4-b. Periodical honeydew excretion was observed in L4-b only. Microsection observation following laser stylectomy revealed that the tips of SBPH stylets severed in L3, L4-a, and L4-b were commonly located in or near the phloem region of rice plants, but were located in the xylem in L5. Plant sap flowed from the stylets severed in L4-b only, and its main carbohydrate component was detected as sucrose by HPLC analysis. These results and the patterns of EPG waveform progress in SBPH suggested that feeding activities on rice plant tissue were relevant to each EPG waveform. L1 and L2 corresponded to the initiation of stylet penetration and stylet movement with salivation on the outside of the vascular bundle. L3 and L4-a were related to feeding activities within the phloem region in preparation for phloem sap ingestion. L4-b was closely associated with phloem sap ingestion, and L5 corresponded to xylem feeding behavior.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.162-165
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• 1996

Various kinds of jeolpyon (cubed rice cake) differing in roasted soybean flour. content (0, 5, 10, 15, 20%) were prepared to study digestibility, degree of gelatinization and retrogradation rate. Digestibility slightly in creased as soybean content increased. Degree of gelatinization also increased as soybean content increased. Retrogradation rate obtained from the changes in hardness of soybean jeolpyon with the control was 0.528 day and time constant (1/k) was 1.89 days.

• Journal of Ginseng Research
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• v.12 no.2
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• pp.153-157
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• 1988

Ultrastructure of inside white part was compared with normal part in Korea Red ginseng by scanning electron microscope. The inside white part was in number and smaller inside of starch particle than those in the normal. The large membranous components in the inside white part seemed to be thinner than those in the normal. Thin membranous components may be related to lower protein content as previously reported. Starch particles in red ginseng were flat and amorphous.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.201-207
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• 2012

This study was conducted to investigate the effect of supporting material and ionic strength of the MS medium on growth of strawberry plantlets cultured in vitro for the rapid mass production. Explants of $Fragaria$ $ananassa$ 'Houkouwase' in vitro were planted in the agar or Tosilee (commercial plug medium) medium as the supporting material and supplied with 1/4 MS, 1/2 MS or basal (as the control) MS medium in an autotrophic micropropagation. Plant height and root length were significantly greater when they were cultured in 1/2 MS medium as compared to those grown in the agar medium. Also, shoot fresh and dry weights, and leaf area in the 1/2 MS medium were greater than in 1/4 MS or basal MS medium. When plantlets were cultured in Tosilee medium and fed with the basal MS medium, plant height, root length, shoot fresh and dry weights, root fresh and dry weights, and leaf area were promoted and greater than those in plantlets cultured in the agar medium.

• Tuberculosis and Respiratory Diseases
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• v.57 no.4
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• pp.345-350
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• 2004

Background : To evaluate the frequency and clinical significance of lymph node micrometastasis in patients of non-small-cell lung cancer pathologically staged to be T1-2,N0. Method : From consecutive 29 patients of non-small-cell lung cancer who received curative operation and routine systemic nodal dissection, we immunohistochemically examined 806 lymph nodes from mediastinal, hilar and peribronchial lesion. All slides were stained with hematoxylin and eosin staining for one section and with cytokeratin AE1/AE3 antibody for another consecutive section of same lymph node to find out micrometastasis. Results : In 806 lymph nodes examined, no tumor cell was seen on hematoxylin and eosin staining and micrometastic foci were shown to be on 0.37%(3) of 806 lymph nodes, in which were upper paratracheal, interlobar and peribronchial lymph node. These three positive stains constitute 10.3%(3) of the 29 patients with non-small-cell lung cancer. Nine patients died from disease progression(4), postoperative complication(3) and concomitant diseases(2). The four patients with disease progression did not show evidence of micrometastasis on their lymph node examination. Conclusion : The frequency of lymph node micrometastasis was in 0.37% of 806 lymph nodes examined. The study results might suggested that routine analysis of micrometastasis on the lymph node didn't give any clinical implication on patients with non-small-cell lung cancer.

• Restorative Dentistry and Endodontics
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• v.32 no.3
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• pp.169-179
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• 2007

This study was to compare the microshear bond strength $({\mu}SBS)$ of light- and chemically cured composites to enamel coupled with four 2-step self-etch adhesives and also to evaluate the incompatibility between 2-step self-etch adhesives and chemically cured composite resin. Crown segments of extracted human molars were cut mesiodistally, and a 1 mm thickness of specimen was made. They were assigned to four groups by adhesives used: SE group (Clearfil SE Bond) AdheSE group (AdheSE), Tyrian group (Tyrian SPE/One-Step Plus), and Contax group (Contax) Each adhesive was applied to a cut enamel surface as per the manufacturer's instruction. Light-cured (Filtek Z250) or chemically cured composite (Luxacore Smartmix Dual) was bonded to the enamel of each specimen using a Tygon tube. After storage in distilled water for 24 hours, the bonded specimens were subjected to ${\mu}SBS$ testing with a crosshead speed of 1 mm/minute. The mean ${\mu}SBS$ (n=20 for each group) was statistically compared using two-way ANOVA, Tukey HSD, and t test at 95% level. Also the interface of enamel and composite was evaluated under FE-SEM. The results of this study were as follows ; 1. The ${\mu}SBS$ of the SE Bond group to the enamel was significantly higher than that of the AdheSE group, the Tyrian group, and the Contax group in both the light-cured and the chemically cured composite resin (p < 0.05). 2. There was not a significant difference among the hdheSE group, the Tyrian group, and the Contax group in both the light-cured and the chemically cured composite resin. 3. The ${\mu}SBS$ of the light-cured composite resin was significantly higher than that of the chemically cured composite resin when same adhesive was applied to the enamel (p < 0.05). 4. The interface of enamel and all 2-step self-etch adhesives showed close adaptation, and so the incompatibility of the chemically cured composite resin did not show.

• The Korean Journal of Pharmacology
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• v.20 no.1 s.34
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• pp.41-46
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• 1984

Cadmium (Cd) was administered by a series of weekly intraperitoneal injections at dose of 2mg/kg in rabbits and rats. The levels of malondialdehyde (MDA) and thromboxane $B^2(TXB_2)$ in platelet-rich plasma from Cd-poisoned animals were significantly higher than those of the control group. Furthermore, the inhibition of 6-keto-prostaglandin $F_{1{\alpha}}$, production in Cd-treated aorta ring was inversely related to the enhancement of platelet aggregation. These results suggest that Cd not only inhibits prostacyclin synthesis in the arterial endothelium, but also stimulates the platelet aggregation by enhancing thromboxane AZ production. These findings are assumed to support the evidence of an effect of Cd toxicity on the vascular wall and platelet function in raising arteriall pressure.