• Parasites, Hosts and Diseases
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• v.23 no.2
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• pp.313-323
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• 1985

Boophilus microplus (Canestrini, 1887) female specimens were subjected to scanning electron microscopy for the observation of surface fine structures. Morphological characteristics observed were summarized as follows: 1. The palpi were wider than long, and compressed, ridged dorsally and laterally. There were usually four pairs of ventro-internal setae on the articles. 2. The hypostome dentition was usually 4/4 but occasionally 5/5. 3. The basis capituli were hexagonal dorsally and the porose area was distinct with the holes developed well. 4. There were numerous folds resembling finger prints around the female genital pore. 5. A pair of anal lobes with specified setae on them was also rocognized as one of the morphological characteristics.

• The Korean Journal of Zoology
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• v.31 no.1
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• pp.21-28
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• 1988

The present study was carried out to examine the fertilizability of the mouse oocytes pre-ex-posed to dbcAMP which is a well-known inhibitor of the oocyte maturation. The oocytes once cultured in the dbcMP-containing medium for a certain length of, time were cultivated in the dbcMp-free medium to induced the maturation, then mixed with sperms, and observed following culture for 24 hours. The fertilization rate of cocytes was judged by the index of the number of 2-cell embryo developed 24hr following insemination. The fertilization rate of the oocyte previously incubated with dbcAMP (100 g/ml) for 2, 4, 8 16 hours was 32.3, 14.5, 4.7 and 8.8%, respectively, while that of the control was 53.3% indicating that the fertilizability was decreased as a function of time exposed to dbcAMP. The pretreatment of dbcMP, however, didn't affect the process of sperm penetration to egg. In addition, there is no prominent changes in the morphological architecture of fertielized eggs which has been exposed to dbcAMP as revealed by electron microscopic observation. Consequendy, it can be concluded that the mouse cocytes once inhibited their maturation by dbcMP may retain, in some extent, the fertilizability, although most of the fertilized egg may not proceed to further development because of the failure of pronucleus formation.

• Elastomers and Composites
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• v.48 no.2
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• pp.141-147
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• 2013

Polyurethanes containing no mesogenic unit were prepared by polyaddition reaction of homo- and copolyurethanes based on para-type 1,4-phenylene diisocyanate (1,4-PDI), 2,6-bis($\omega$-hydroxypentoxy)naphthalene (BHN5) with 1,4-bis($\omega$-hydroxypentoxy)benzene (BHB5). All copolyurethanes showed monotropic liquid crystallinity, when measurements were performed under shearing. For example, a polyurethane Poly(50/50, mol%) with $[\eta]$=0.32 dL/g exhibited liquid crystallinity in the temperature range from $223^{\circ}C$ to $211^{\circ}C$ in the cooling stage. In contrast, two homopolyurethanes exhibited no explicit mesomorphic behavior, which was observed by DSC (Differental Scanning calorimeter) and measurement and polarized microscopic observation. The mesomorphic behavior of synthesized polyurethane was identified and characterized by differential scanning calorimetry, polarized optical microscope and X-ray.

• Journal of Ginseng Research
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• v.16 no.3
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• pp.222-227
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• 1992

Unlike carbohydrats and fats, alcohol is essentially foreign to the body and it is known that the body get rid of it by oxidizing alcohol maily in the liver. Acetaldehyde is produced during ethanol metabolism and is known to be oxidized mainly by aldehyde dehydrogenase (ALDH). ALDH activity was found mainly in the mitochondrial fraction but a significant ALDH activity was also present in microsomal and cytosol fraction. Wistar rats (150~200 g, male) were given freely with 12% ethanol (Control) and/or 12% ethanol containing 0.1% ginseng saponins (Test) instead of water for 6 days and the liver was analyzed. ALDH activities of both control and test group were lower than that of normal group but test AkDH was less inhibited than control. ADH activies of both control and test were slightly higher than that of normal group but our previous data showed that it became gradually steady after prolonged ethanol feeding. MEOS activities of both control and test group were much higher than that of normal group. MEOS enzymes are inducible but the activity of test group was greatly higher than that of control. Ethanol containing [1-i4C] ethanol (5 $\mu$Ci) was injected to the above three groups and 30 min later, the distribution of radioactivity of hepatic lipids was investigated. Radioactivities of hepatic lipids of both control and test group were higher than that of normal group, however, that of test group was much lower than that of control. Analysis of individual lipids showed that phospholipid biosynthesis was significantly impaired and fatty acid and triglycerides biosynthesis were greatly stimulated. However, it was realized that the saponin prevented phospholipid biosynthesis depression and the increase of triglyceride biosynthesis considerably. It seemed that the saponin might stimulate ADH, ALDH and MEOS and the acetaldehyde formed would be removed faster. The excess hydrogen can be shunt more quickly into lipid biosynthesis. Electron microscopic observation showed that the hepatic cell of control group was si gnificantly damaged. Mitochondria were swollen and rough endoplasmic reticulum were dilated, however, hepatocytes of test group were not damaged.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.85-89
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• 1999

Somatic embryogendesis is one of good examples of the basic research for plant embryo development as well as an important technique for plant biotechnology. This paper describes the direct somatic embryogenesis from zygotic embryos of Panax ginseng is reversely related to normal axis growth of zygotic embryos by the experiment of various chemical treatments. Under the normal growth condition, the apical tips of embryo axis produced an agar-diffusible substance, which suppressed somatic embryo development from cotyledons. Although the cells of zygotic embryos were released from the restraint of embryo axis, various factors were still involved for somatic embryo development. Electron microscopic observation revealed that the ultrastructure of cells of cotyledon epidermis markedly changed before initiation of embryonic cell division, probably indicating reprogramming events into the cells embryogenically determined state. Polar accumulation of endogenous auxin or cell-cell isolation by plasmolysis pre-treatment is the strong inducer for the somatic embryo development. The cells for the process of somatic embryogenesis might be determined by the physiological conditions fo explants and medium compositions. Direct somatic embryos from cotyledons fo ginseng were originated eithrer from single or multiple cells. The different cellular origin of somatic embryos was originated either from single or multiple cell. The different cellular origin of somatic embryos was depended on various developmental stages of cotyledons. Immature meristematic cotyledons produced multiple cell-derived somatic embryos, which developed into multiple embryos. While fully mature cotyledons produced single cell-derived single embryos with independent state. Plasmolysis pretreatment of cotyledons strongly enhanced single cell-derived somatic embryogenesis. Single embryos were converted into normal plantlets with shoot and roots, while multiple embryos were converted into only multiple shoots. GA3 or a chilling treatment was prerequisite for germination and plant conversion. Low concentration of ammonium ion in medium was necessary for balanced growth of root and shoot of plantlets. Therefore, using above procedures, successful plant regeneration of ginseng was accomplished through direct single embryogenesis, which makes it possible to produce genetically transformed ginseng efficently.

• The Korean Journal of Zoology
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• v.33 no.1
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• pp.12-21
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• 1990

When a piece of the dorsal skin(cat fish) was observed under a light microscope, melanophores were horizontally expanded and had a few processes filled with melanosomes. They were isolated from one another. Some melanophores looked black, while others were d&k brown. On observation with a transmission electron microscope, the epidermal melanophore of cat fish was highly branched and small segments of processes were found frequendy m the vidnity of the interecellular spaces. The cross section of the processes of melanophore was almost circular, and often invested by a thin layer of epidermal cells. Some processes, however, occurred free m the wide interecellular spaces or at the cytoplasm of the superilcial layers. In the mature melanophore, the cell organelles including melanosomes, mitochondria and free ribosomes were prominent in the perinuclear portions. Many melanosomes were spherical or elipsoidal in shape. Each melanosomes was surrounded by a limiting membrane. The processes of the mature melanophore were well developed, but the processes of the immature melanophores were incompletely developed.

• Journal of Veterinary Clinics
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• v.26 no.3
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• pp.200-204
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• 2009

This study was performed to evaluate the effects of reduced L-glutathione on the oxidant/antioxidant status(superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase(GPx), protein carbonyl and lipid hydroperoxide(LPO) concentration), renal function(blood urea nitrogen(BUN) and serum creatinine levels), and microscopy of renal tissues in pigs undergoing unilateral renal ischemia-reperfusion(I/R). Sixteen Landrace and Yorkshire mixed-breed pigs were divided randomly into two groups: untreated control group and reduced L-glutathione-treated group(4 mg/kg IV). Each group had 8 pigs. Pigs were unilaterally nephrectomized and the kidney was subject to 30 min of renal pedicle occlusion. Blood samples for biochemical assay were collected on days 1, 3, 5, 7, and 14 post nephrectomy. Renal I/R injury were evaluated histopathologically by the microscopic observation of renal tissue sections and biochemically by the measurement of the plasma creatinine and urea levels. Parameters of oxidative stress such as SOD, GPx, CAT, protein carbonyl and LPO were measured. The elevation of creatine and BUN levels was lower in the treated group, compared with the control group. The activities of antioxidant-enzyme were higher in the treated group, compared with the control group. In histological findings, the severity of damage in the reduced L-glutathione treated group was less when compared to the control group.

• Journal of Veterinary Clinics
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• v.26 no.3
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• pp.306-310
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• 2009

Mass mortality was occurred in adult koi carp(Cyprinus carpio) at a private pond near Samchunpo city in the early November, 2007. Its water temperature was $11^{\circ}C$ and turbidity was very high. The fishes diseased were shown widely distributed hemorrhages, deep ulcerations on the whole body surface and severe erosions in the all fins. In necropsy, excess ascitic fluid was observed and spleen and kidney affected were enlarged. In microscopic observation, it was examined widely distributed severe dermal ulceration, multifocal gill lamella hyperplasia, severe fibrinous pericarditis, multifocal nephritis and hepatitis. The bacteria suspected were isolated using tryptone soya agar and identified as motile Aeromonas hydrophila as results of biochemical tests using API 20E and 20NE. According to previous reports, A. hydrophila infection were mainly occurred in fingerling at high temperature. However, this case exhibited that A. hydrophila infection can develop on adult koi carp even in the winter season.

• Journal of the Korean Wood Science and Technology
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• v.15 no.2
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• pp.79-89
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• 1987

This study was executed to examine helical structure and other feature, of Taxus cuspidata S. et Z. and Larix gmelinii var. principis-ruprechtii Pilger through photomicroscopic and scanning electron microscopic observation, and the obtained result, were summarized as follows: 1. Tracheid transition from springwood to summerwood was abrupt, mel slightly gradual in Taxus cuspidata S. et Z. and summerwood width of Larix gmelinii var. principis-ruprechtii Pilger was wider than that of Taxus cuspidata S. et Z. 2. Normal vertical and horizontal resin canals and surrounding thick epithelial cells were present in Larix gmelinii var. principis-ruprechtii Pilger but not present in Taxus cuspidata S. et Z. 3. Instead of helical thickening, helical chicks were observed only in summerwood trachieds of Larix gmelinii var. principis-ruprechtii Pilger. However, helical thickenings forming S, Z., and horizontal helix perpendicular to long axis of tracheid were observed in springood and summerwood tracheids of Taxus cuspidata S. et Z. and these helical thickenings were considered as analogous to the innermost layer of secondary wall. 4. Uniseriate and fusiform rays were appeared on tangential surface of Larix gmelinii var. principis-ruprechtii Pilger but oly uniserate ray was observed on tangential surface ot Taxus cuspidata S. et Z. The fusiform rays of Larix gmelinii var. principis-ruprechtii Pilger usually contained one horizontal resin canal bot occasionally two horizontal resin canals were contained in a fusiform ray. 5. Trabeculae and crassulae were observed in the tracheids of Larix gmelimii var. principis-ruprechtii Pilger but not observed in the tracheids of Taxus cuspidata S. et Z.

• Journal of Conservation Science
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• v.32 no.4
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• pp.571-578
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• 2016

This study analyzed the pigments used in two portraits of Sim Hui-su using scanning electron microscopy/energy dispersive spectroscopy(SEM/EDS), X-ray diffraction(XRD) analysis, and microscopic observation, and then compared the results to those from nondestructive analysis. It was estimated that cinnabar/vermilion and minium were used for the red pigment, azurite for the blue pigment, atacamite for the green pigment, and lead white for the white pigment. These results were compared to the pigments of six portraits with a similar format, full-length official-attire portraits from the $17-18^{th}$ century Joseon period. It was revealed that the composition of the pigments used in the portraits varied depending on the date of production. Iron oxide, another red pigment, was used in the $18^{th}$ century. As for the blue colorant, smalt was used in the late $18^{th}$ century, whereas it was absent until the early $18^{th}$ century.