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561.
Hwan-Goo Kang Sang-Hee Jeong Joon-Hyoung Cho 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(1):51-58
The methanol extract from the leaves of Petasites japonicus Maxim (PJ) was studied for its (anti-)mutagenic effect with the SOS chromotest and reverse mutation assay. The (anti-)carcinogenic effects were evaluated by the cytotoxicity on human cancer line cells and by the function and the expression of gap junctions in rat liver epithelial cell. PJ extracts significantly decreased spontaneous β-galactosidase activity and β-galactosidase activity induced by a mutagen, ICR, in Salmonella (S.) typhimurium TA 1535/pSK 1002. All doses of the extract (0.08-100 mg/plate) decreased the reversion frequency induced by benzo (α)pyrene (BaP) in S. typhimurium TA 98. It decreased not only the spontaneous reversion frequency but also that induced by BaP in S. typhimurium TA 100. PJ extract showed greater cytotoxic effects on human stomach, colon and uterus cancer cells than on other cancer cell types and normal rat liver epithelial cells. Dye transfers though gap junctions were significantly increased by PJ extracts at concentrations greater than 200 µg/mL and the inhibition of dye transfer by 12-O-tetradecanoylphorobol-13-acetate (TPA) was obstructed in all concentrations of PJ. PJ significantly increased the numbers of gap junction protein connexin 43, and increased the protein expression decreased by TPA in a dose-dependent manner. Based on these findings, PJ is suggested to contain antimutagenic and anticarcionogenic compounds. 相似文献
562.
A series of amorphous poly(lactic acid) (PLA) monofilaments with various D-isomer contents of 1∼9 mol% have been prepared
and then elongated uniaxially at 25∼65 °C in the glass transition region. Both initial modulus and maximum strength of PLA
monofilaments are appreciably decreased with increasing the temperature, especially at ∼50 °C, and they were somewhat lower
for the monofilament with higher D-isomer content. Structural evolution, chain orientation, and thermal properties of PLA
monofilaments drawn uniaxially with various draw ratios at 65 °C were then investigated by using wide-angle X-ray diffraction,
polarized Raman spectroscopy, and differential scanning calorimetry, respectively. X-ray diffraction patterns clearly exhibited
the development of chain orientation and stain-induced crystallization of the monofilaments as a function of draw ratio (DR).
The dichroic ratio, a measure of the chain orientation, was quantitatively evaluated from the polarized Raman spectra. It
was revealed that the dichroic ratios increased up to DR=4 and decreased slightly at DR>4 owing to the strain-induced crystallization
for PLA monofilaments with D-isomer contents of 1 and 4 mol%. The glass transition and cold-crystallization temperatures of
PLA monofilaments increased and decreased, respectively, with the increment of DR. The strain-induced enthalpy relaxation
endothermic peak appearing in glass transition region became intense with increasing the DR. 相似文献
563.
We report herein a superhyrodrophobic poly(ethylene terephthalate) (PET) fabric prepared through a biomimetic method of the
Lotus effect. To attain the Lotus effect on the PET fabrics, physical roughness and chemical hydrophobicity were controlled
by adopting silica nanoparticles and a commercial water-repellent agent, respectively. For this, narrow-size distributed silica
nano-particles were prepared by a sol-gel process. The water contact angle on PET fabric treated with both silica nanoparticles
and water-repellent agent reached 158°, which was much higher than 137° reached by the fabric treated with the water-repellent
agent only. 相似文献
564.
Tight-fitting clothing pattern reflecting the accurate information of the 3D body shape has been one of the challenges for
garment industry especially for those who have an abnormal body shape. The objective of the paper is to develop the process
of making a final 2D pattern from 3D scanned surface with minimum errors that fit tightly to an asymmetrical female manikin
and secondly, to verify the proposed pattern development process from the free drawn design line on the specific 3D body.
On the continuum of the previous methodology which provided the precise flattening algorithm on the local 3D surface, total
pattern making process was investigated step by step. Final 2D pattern was constructed using non-extensible fabric and the
accuracy of the pattern was investigated by shell-shell deviation of original 3D nude and clothed image. Area of each pattern
block and corresponding 3D surface block was compared, and the detailed view of the triangle arrangements for the final pattern
examined, confirming the topology of the concave and convex surface reflected correctly in the pattern. As results, the accuracy
of the tight-fit dress pattern was satisfactory even for the asymmetrical female manikin with prominent curvature. 相似文献
565.
Jin Sook Kim Hyun Jeong Jeon Kyung Min Lee Jung Nam Im Ji Ho Youk 《Fibers and Polymers》2010,11(2):153-157
Polyacrylonitrile (PAN) nanoparticles were successfully prepared by dispersion polymerization of acrylonitrile (AN) in water
using 10 and 20 wt% of the poly(ethylene oxide)-b-PAN macromolecular RAFT (PEO-b-PAN macro-RAFT) agent (M
n=5,600 g/mol, PDI=1.15). The degrees of polymerization of the PEO and PAN blocks were 113 and 16, respectively. The PAN nanoparticles
had a crumpled spherical appearance and their sizes ranged from 50–80 nm. The degree of crystallinity of the PAN particles
was 23 %. The M
n
values of the PAN nanoparticles prepared with 10 and 20 wt% of the PEO-b-PAN macro-RAFT agent were 33,900 and 25,800 g/mol, respectively. The existence of the PEO block on the surface of the PAN
nanoparticles was confirmed by 1H NMR spectroscopy and XPS. 相似文献
566.
Hyojung Kim Jongyeul Baek Yeon-Ok Choi Jeong Hyun Lee Soon-Kee Sung Sunggil Kim 《Euphytica》2010,171(2):241-249
A cluster of oligonucleotide repeat sequences was identified that is linked to the melon (Cucumis melo L.) andromonoecious (a) locus, which controls andromonoecy. Six different repeat units, ranging from 11 to 49 base pairs, were clustered within
a 0.6-kb intergenic region. The number of repeat units varied from two to six. After sequence analysis of diverse melon germplasms,
four haplotypes of this cluster were identified. Length variations among the four haplotypes resulted from insertion or deletion
of repeat sequences. Particularly, a tandem array of six repeats of 21 nucleotides was a hotspot for insertion/deletion mutations.
A simple PCR-based marker was developed to identify haplotypes of this cluster based on the length polymorphism. In practice,
this marker was successfully used in genetic purity tests of melon F1 hybrid cultivars. Four self-pollinated contaminants, which were confirmed by phenotypic examination in grow-out tests, were
easily discriminated from 99 F1 hybrid individuals. In addition, the genetic distance between this marker and the andromonoecious (a) locus was calculated as 7.9 cM, after analyzing melon F2 populations originating from a cross between monoecious and andromonoecious parental lines. Therefore, this marker will be
useful as a recombinant selection marker in marker-assisted backcrossing of monoecy in melon breeding programs. 相似文献
567.
Gi Young Jeong Jin Hyuk Kong Sang Joon Lee Sung-Jun Pang 《Journal of Wood Science》2018,64(3):237-245
The goal of this study was to analyze the bearing properties of the differently oriented glulam using digital image correlation (DIC). Six differently oriented specimens associated with three anatomical directions including longitudinal (L), radial (R), and tangential (T), and 12-mm drift pins were used to analyze the bearing properties, including yield load and bearing strength. The highest bearing strength of 22.57 MPa from RL was found, whereas the lowest bearing strength of 6.47 MPa from LR was found. Different strain distributions were observed from the differently oriented bearing specimens using DIC. Different failure ratios of the differently oriented specimens were highly related to the strain distributions. Although the bearing properties were found to be different between the differently oriented specimens, for the connection design aspect, the bearing properties of glulam could be grouped as RL and TL specimens, RT and TR specimens, and LR and LT specimens. 相似文献
568.
Pharmacokinetics and Acid Suppressant Efficacy of Esomeprazole after Intravenous,Oral, and Subcutaneous Administration to Healthy Beagle Dogs
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569.
Jung-Kyung Moon Soon-Chun Jeong Kyujung Van M. A. Saghai Maroof Suk-Ha Lee 《Euphytica》2009,169(3):375-385
Soybean plants react differentially to soybean mosaic virus (SMV) strains because of interactions among different resistant
genes in the soybean genome. Three independent genes resistant to SMV have been identified by inheritance studies and linkage
analyses. To develop durable SMV-resistant soybean cultivars, it is necessary to determine which soybean SMV resistance genes
can be readily transferred from resistant to susceptible cultivars in a breeding system. Here, we report the type and number
of resistance gene(s) in four Korean elite soybean cultivars using a combination of disease reaction symptoms, inheritance
studies, and molecular marker mappings. The disease reactions of Sowonkong and Keunolkong soybean varietals in response to
infection with SMV strains suggested that both cultivars most likely harbor the Rsv1 gene similar to that in York. Subsequent inheritance studies confirmed that Sowonkong has the Rsv1 gene. The inheritance studies suggested that Sinpaldalkong harbored the Rsv1 gene, which was then confirmed by molecular marker mapping. The inheritance studies also suggested that Jinpumkong 2, which
is the most resistant to SMV infection among the four cultivars, contained the Rsv1 and Rsv3 genes; this was confirmed by molecular marker mapping. Our approach, which combined inheritance studies and molecular linkage
analyses, allowed the efficient identification of resistance gene(s) in four Korean soybean cultivars. 相似文献
570.