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        검색결과 368

        201.
        2014.10 구독 인증기관·개인회원 무료
        Insect pollinators of the endanger orchid Cypripedium japonicum were surveyed and identified during two years, as a part of a conservation project of the orchid at Jukyeup-san and Hwaak-san (Mt.), South Korea. In total 40 individuals of 16 species in 4 families were identified. The dominant family was Halictidae, and Lasioglossum exiliceps Vachal visited the most frequently C. japonicum during the surveys. The average visiting frequency was 2.5 individuals per hour and the highest 4.3, from 12:00 – 13:00 in a day. After 15:00 insects did not visit the flowers at all. However, all of the visiting insects were found to not carry a pollinium or pollens of the orchard on their bodies; pollen carryover by any of the visiting insects did not occur at all. The orchid seems to require certain pollinators in particular body thickness due to its unique pollination mechanism. The orchid has two exit route openings, around 1 cm in diametre, where the entrapped insects can exit and an anther is situated just in front of each opening. It was inferred that a pollen carrier should be around 1 cm in body thickness. Therefore, the candidate species as the proper pollen carriers can be Tetralonia nipponensis Perez, Xylocopa appendiculata circumvolans Smith and Bombus consobrinus Dahlbom among the surveyed visitors.
        202.
        2014.10 구독 인증기관·개인회원 무료
        A partial sequence of the mitochondrial cytochrome oxidase subunit I (COI) gene is widely used as a molecular marker for species identification in animals, also termed a DNA barcode. However, the presence of more than one sequence type in a single individual, also known as heteroplasmy, is one of the shortcomings of barcode identification. In this study, we examined the extent and divergence of COI heteroplasmy, including nuclear-encoded mitochondrial pseudogenes (NUMTs), at the genomic-DNA level from 13 insect species, including four individuals of orthopteran Anapodisma miramae. Furthermore, a long fragment of mitochondrial DNA (~13.5 kb) and cDNA from A. miramae were used as a template for COI PCR to compare the patterns of heteroplasmy between DNA sources and to investigate a possible way to avoid ambiguity in DNA barcoding. When multiple numbers of clones originated from genomic DNA were sequenced, heteroplasmy was prevalent in all species (3~16 heteroplasmic copies), with a varying degree of maximum sequence divergence (<1% in 7 species, <4% in 3 species, <6% in 2 species and 2.15-8.03% in four A. miramae individuals). In five species, NUMTs also were observed when genomic DNA was used as a template. Long fragment DNA also is a source of heteroplasmic amplification, but the divergent haplotypes and NUMTs obtained in the genomic DNA-based PCR were not detected in A. miramae. On the other hand, cDNA was heteroplasmy-free, without NUMTs when multiple numbers of clones were sequenced. Consistently, one dominant haplotype was always obtained from the genomic DNA-origin clones in all species and also from the long fragment- and cDNA-origin clones of A. miramae. Furthermore, the dominant haplotype was identical in sequence, regardless of the DNA source. Thus, one possible solution to avoid the barcoding problem in relationship to heteroplasmy could be the acquisition of multiple numbers of barcoding sequences to determine a dominant haplotype that can be assigned as barcoding sequence for a given species.
        203.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Brucellosis is a notorious zoonotic disease with global implications. Efforts to control the spread of the disease have been restricted to the agricultural livestock. Increasing incidences of accidental human infection have motivated researches to start working on alternative vaccines. At present, live attenuated vaccines are the only accepted type of vaccines used in developed countries for the prevention of brucellosis. Although serodiagnosis is occasionally unreliable, some countries have already claimed to have eradicated the disease, based on this testing. Live attenuated vaccines are not suitable for use in pregnant and immune-depressed animals. Moreover, these vaccines are not tolerated in humans. Therefore, many researches have been striving to discover alternative methods of vaccination. Most research has focused on the generation of subcellular, subunit, and DNA vaccines that are as efficient as the live attenuated vaccines. At present, none of the available vaccines has been able to replace the live attenuated vaccines. Therefore, additional research is necessary in order to discover a new brucellosis vaccine that is suitable for human use.
        4,000원
        206.
        2014.04 구독 인증기관·개인회원 무료
        In this study, we investigated the effects of X-ray irradiation to control six important insect pests of floriculture crops: Liriomyza trifolii, Spodoptera litura, Myzus persicae, Tetranychus urticae, Bemisia tabaci, and Frankliniella intonsa. We irradiated on six insect pests that were placed in different positions (top, middle, and bottom) of export flower boxes after filling the boxes with roses and chrysanthemums, respectively. When irradiated with X-ray of 150 Gy, the eggs of T. urticae, B. tabaci, F. intonsa, L. trifolii, and S. litura were prevented from hatching at every position in the boxes. The pupation and emergence of L. trifolii larvae and S. litura larvae and B. tabaci nymphs and F. intonsa nymphs were inhibited at every position in the boxes. However, the emergence of T. urticae and M. persicae nymphs was not inhibited, even at the top position in the boxes. When pupae were irradiated, the emergence of L. trifolii was inhibited at every position in the boxes, while S. litura was not inhibited completely, even at the top position in the boxes. When adult T. urticae, S. litura, and L. trifolii were irradiated, the hatching rate of the F1 generation was not completely inhibited at every position. The insect pests that were not inhibited completely at the dose of 150 Gy showed much higher inhibitory effects at the dose of 250 Gy. Therefore, the dose of X-ray irradiation required to inhibit may vary according to the types of flowers and insect pests and according to their positions within the boxes.
        207.
        2014.04 구독 인증기관·개인회원 무료
        Three insect pest, Myzus persicae, Tetranychus urticae, and Liriomyza trifolii were irradiated with electron beam (50-250 Gy) or X-ray (10-150 Gy). Longevity, egg hatching, emergence and fecundity of the test insects were measured. When irradiated to the M. persicae, emergence of nymphs did not show any differences, but fecundity was inhibited at 100 Gy (electron beam) or 30 Gy (X-ray). When irradiated to the T. urticae, egg hatching was completely inhibited at 150 Gy (electron beam) or 50 Gy (X-ray) and egg hatching of F1 generation was decreased at 150 Gy of electron beam or 50 Gy of X-ray. When irradiated to the L. trifolii, egg hatching was completely inhibited at 30 Gy of X-ray, however, electron beam irradiation was not inhibited even at 200 Gy. Egg hatching from irradiated adults was completely inhibited at 150 Gy of electron beam and X-ray. These results indicate that electron beam and X-ray irradiation induced abnormal development and reproduction, however, the dose of irradiation required to inhibit may vary according to the types of insect pests.
        208.
        2014.04 구독 인증기관·개인회원 무료
        The effects of X-ray irradiation on development and reproduction of Spodoptera litura were examined. Eggs, larvae, pupae, and adults were irradiated at target doses of 10 - 250 Gy. When eggs were irradiated with 30 Gy, egg hatching was completely inhibited. When irradiated to the larvae, pupation was inhibited at 100 Gy and larval period was delayed. When irradiated to the pupae, emergence was inhibited at over 100 Gy. When irradiated to the adults, longevity and fecundity did not show any differences. However, egg hatching was significantly decreased at 70 Gy and above. Also, X-ray irradiation was not induced the rapid death of S. litura. Reciprocal crosses between irradiated and unirradiated moths demonstrated that males were more radiotolerant than females. The levels of DNA damage in S. litura adults were evaluated using the alkaline comet assay. Our results indicate that X-ray irradiation increased levels of DNA damage. The recovery of DNA damage in S. litura adults increased as time passed. But DNA damage hasn't recovered fully. These results indicate that X-ray irradiation induced abnormal development and reproduction by DNA damage in S. litura.
        209.
        2014.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Brucellosis is an important bacterial zoonotic infection worldwide responsible for economic losses in livestock industries which represents a considerable and increasing public health burden. The disease is caused by Brucella which possess the ability to invade and replicate within phagocytes and may result to chronic infection, leading to difficulty in medical therapy of the disease. The treatment for brucellosis employs conventional principles that have been applied for a long time and a combination of antibiotics is currently used due to low efficacy of monotherapies. However, vital effects with respect to health and safety are neglected. Nevertheless, the preventive methods and treatments for brucellosis using traditional medicine have not yet been thoroughly studied, hence, alternative therapies such as the use of natural plant extracts as traditional medicine that are safe, efficient and economical should be explored in order to identify candidates that eliminate complications due to brucellosis. Coptis chinensis Franch (Huanglian) is a traditional Chinese medicinal herb and its extract has been known to possess strong antibacterial activity. In this study, the antibacterial effects of C. chinensis Franch extracts, and the major components of the herb namely berberine and palmatine, were investigated on B. abortus. The C. chinensis Franch ethanol extracts (CCFE) showed bactericidal effects at 1,000 μg/ml concentration and berberine at 100 μg/ml concentration. However, C. chinensis Franch and its components did not affect invasion and intracellular growth of B. abortus in RAW 264.7 cells. In conclusion, C. chinensis Franch ethanol extracts, water extract and its major components such as berberine and palmatine would be a beneficial antimicrobial agent without affecting phagocytic pathway within macrophages, and further study for the precise mechanisms of antibacterial effect would be necessary.
        4,000원
        210.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        [6]-Gingerol, a major polyphenol of ginger(Zingiber officinale), exhibits a variety ofbiological properties including anti-oxidant, anti-inflammatory and anti-cancer activity. However,the radioprotective effect of [6]-gingerol is still unknown. The aim of this study was to investigatethe radioprotective effect of [6]-gingerol against radiation-induced cell cytotoxicity and oxidativestress in HepG2 cells. [6]-Gingerol pretreatment attenuated radiation-induced cell cytotoxicitycaused by 5Gy(half lethal dose, LD50of HepG2 cells). The measurements of superoxide dismutase(SOD) and catalase(CAT) activity were also performed. The results showed that [6]-gingerol pre-treatment reduced increasing SOD and CAT activity after exposure of IR, indicating that [6]-gin-gerol protected oxidative stress by regulating cellular antioxidant enzyme(SOD and CAT) activity.These findings suggest that [6]-gingerol acts as a radioprotector by attenuating cell cytotoxicityand oxidative stress.
        4,000원
        211.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Brucella spp. are facultative intracellular pathogens that have the ability to survive and multiply in professional and nonprofessional phagocytes and cause abortion in domestic animals and undulant fever in humans. Brucella species can survive in a variety of cells, including macrophages and their virulence and chronic infections are thought to be due to their ability to avoid the killing mechanisms within macrophages. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival of Brucella in professional and nonprofessional phagocytes. Toll-like receptors (TLRs) are part of a skillful system for detection of invasion by microbial pathogens. Recognition of microbial components by TLRs triggers signaling pathways that promote expression of genes and regulate innate immune responses. Recent studies for the interaction between TLRs-Brucella have indicated the importance of control of Brucella infection. Here, we review selected aspects of TLRs-Brucella interaction, which may be helpful to understanding the mechanism of Brucella pathogenesis.
        4,000원
        212.
        2013.10 구독 인증기관 무료, 개인회원 유료
        The multi-tactile stimulation system was developed to analyze cognitive function characteristics. The developed system consists of three units; control unit, drive unit and actuator that simultaneously and separately supports the vibration, heat, and pressure stimulation. From the results, vibration stimuli have a wide frequency range of 0-300 Hz comprising 20 levels, and stimulation intensity comprising 40 levels. The control temperature and stimulation temperature used for heat stimulation comprise four and eight levels, respectively. Pressure stimuli in the range of 0-600 mmHg can be stimulated comprising 12 levels. Therefore, the developed stimulator can be used for integrative tactile perception and cognition studies on various vibration, heat and pressure sensations.
        3,000원
        213.
        2013.10 구독 인증기관 무료, 개인회원 유료
        In this paper, we developed a power amplifier system for driving a solenoid coil. The developed system consists of three units; control unit, drive unit and coil. The control unit generates a drive signal of sinusoidal wave type, monitors an operating status of the drive unit and vibration characteristics of the coil. The drive unit drives a solenoid coil in response to command from the control unit. The coil was fabricated with the size of diameter in 1.5 cm and length in 1.7 cm using electric copper wire. 4 types of drive unit were tested with thermal and vibration characteristics of the coil using temperature sensor and 3-axis accelerometer, respectively. From the result, the developed system has many advantages with respect to simple control algorithm, small size, and operates stably up to 68 watts driving condition.
        3,000원
        215.
        2013.10 구독 인증기관·개인회원 무료
        We sequenced 17,329 bp of mitochondrial genome (mitogenome) of the black dwarf honey bee, Apis andreniformis (Hymenoptera: Apidae), that lacks ~200 bp of the A+T-rich region for the completion of the genomic sequence. The gene arrangement of A. andreniformis mitogenome is identical to that of A. cerana. However, the genome contains 5 additional tRNALeu(CUN) located 4 copies between tRNAMet and tRNAGln, and 1 copy between tRNAGln and tRNAAla, along with the typical sets of genes (13 protein-coding genes, 22 tRNAs, and 2 rRNAs) including regular tRNALeu(CUN) and the A+T-rich region (at least 923 bp). Only 1 copy of tRNALeu(CUN) differed by 1 bp from other 4 copies of tRNALeu(CUN). Each additional tRNALeu(CUN) is followed by nearly identical 68-bp long repeat sequence (95.6% identity). All 13 protein coding genes have typical start codons found in insect mitochondrial PCGs (2 ATA, 9 ATT, and 2 ATG).
        216.
        2013.09 구독 인증기관 무료, 개인회원 유료
        Patients referred to the Veterinary Medical Center at Chungbuk National University were analyzed. This study aimed to provide information to clinicians in Korea on the factors affecting fracture incidence in patients adapted to Korean companion animal culture. Eighty cases showing- bone fractures were investigated from January, 2005 to De- cember, 2011. Fractures were mainly observed in miniature dogs such as Yorkshire terrier (12%), Poodle (12%), and Maltese (9%). Almost 50% of all cases were less than 1 year old. Total bone fractures in summer and fall constituted 62%. Fracture incidence was higher in male dogs (54%) than female dogs (46%). Hindlimb fracture (37%) was the most common. Distribution of limb fractures was higher in the femur (19), followed by the tibia/fibula (15), radius/ulna (13), humerus (11), and mandible (8). Pelvic fracture was observed in 19 cases. Simple fracture (84%) was the most common fracture type, followed by comminuted fracture (16%). Distal portion was the most common fracture site in long bones (67%), followed by middle (26%) and proxi- mal bones (7%). Fractures were mainly caused by traffic accidents (43%), whereas 28.5% of fractures were due to falling down. Plate & screw (26%) was the most common method of fracture repair, followed by intramedullary pin (24%), wire (11%), external skeletal fixation (10%), screw (9%), amputation (7%), cross pin (6%), IM pin and wire (5%), and rush pin (1%). Among 80 patients, 79%of pa- tients showed a good prognosis after surgery, whereas 13% patients did not experience a good result. This study shows that miniature dogs are prone to falling and fractures, espe- cially in the distal part of long bones.
        4,000원
        217.
        2013.06 구독 인증기관 무료, 개인회원 유료
        An efficient plant regeneration protocol is developed for a standard-type chrysanthemum. When petal segments derived from flower buds (4 or 8cm in diameter) were used as the culture material, the highest shoot regeneration frequency (96%) was obtained on a Murashige and Skoog (MS) medium supplemented with 0.5 mg/L IAA, 2 mg/L BA, 3% sucrose, and a 0.8% agar. Pre-culturing the explants under dark conditions for 14 days produced better results for the shoot regeneration frequency than the explants cultured under a continuous 16 h photoperiod (40 μmolm-2 s -1 ). The shoot regeneration frequency ranged from 19.0% for the Shinmato cultivar to 89.1% for the Baeksun cultivar. Activated charcoal (0.2%) enhanced the root formation of the regenerated shoots in a hormone-free MS medium. The rooted plantlets were acclimatized and successfully established in a greenhouse.
        4,000원
        218.
        2013.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Brucellosis is an important bacterial zoonosis in humans and domestic animals. Brucella spp. are taken up, and survive within non-professional and professional phagocytes. In common belief, diabetes mellitus increases susceptibility to pathogenic infection. In this study, Brucella (B.) abortus was inoculated into a diabetic animal model, db/db mice, in order to show the course of brucellosis in diabetic state. The liver proliferation, bacterial burden of the liver, level of cytokines in serum and macrophage migration into liver, were investigated at 14 days post-infection. In comparison with the uninfected control mice, the results revealed that the weight of the liver of infected db/db mice was higher but with lower bacterial load in this organ. The level of MCP-1 mRNA expression in the liver was lower, the levels of IL-12p70, IL-10, TNF-α and IFN-γ in serum was significantly higher and the macrophages migration was significantly lower in infected mice than in the control group. In conclusion, this present study suggested that MCP-1 suppression by B. abortus infection may inhibit the macrophages migration, and consequently may induce to abrogate the bacterial survival in db/db mouse liver. Furthermore, the increased inflammatory cytokines may contribute to inhibition of B. abortus proliferation in diabetic mice.
        4,000원
        219.
        2013.04 구독 인증기관·개인회원 무료
        Hipparchia autonoe belongs to the family Nymphalidae (Lepidoptera) and is designated as an endangered insect and national monument in Korea. It only inhabits a very restricted area on Mt. Halla but is widely distributed in several Asian countries including Mongolia. A previous study conducted to understand the genetic relationship between Mt. Halla and Mongolian H. autonoe for conservation purposes suffered from a limited number of samples. Therefore, we sequenced the DNA barcode region of an additional 36 H. autonoe individuals, combined them with previous data from 19 individuals, and performed phylogenetic and population genetic analyses. Furthermore, the internal transcribed spacer 2 (ITS2) region was also sequenced from the 36 samples as a nuclear DNA marker. The existence of independent haplotypes, sequence types, and significant FST estimates (p < 0.05) between Mt. Halla and Mongolian populations indicated hampered gene flow between the populations. Nevertheless, an absence of a reciprocal monophyletic group in Mt. Halla and Mongolian populations by cytochrome oxidase subunit I gene- and ITS2-based phylogeny suggests that the genetic isolation of the Mt. Halla population from the Mongolian populations seemed not large enough to consider them independent genetic entities.
        220.
        2013.04 구독 인증기관·개인회원 무료
        In the present study, the 17,694-bp long complete mitochondrial genome (mitogenome) of the dwarf honey bee, Apis florea (Hymenoptera: Apidae), is described with an emphasis on the noteworthy triplicated tRNAser(AGN) region and an extraordinary long A+T-rich region with repeat regions. The gene arrangement of A. florea mitogenome is identical to that of A. mellifera, but has triplicated tRNASer(AGN), each of which contains the precedent 44 bp-long and following another 64 bp-long repeats plus one complete first repeat abutting to tRNAMet. A total of 1,610-bp long two repeat regions in 1,987 bp-long A+T-rich region is composed of nearly identical 141 ~ 219-bp long five tandem repeats and 50 ~ 52-bp long 12 tandem repeats that are encompassed by three non-repeat sequences. One of the common interpretations for such repeat sequence is slipped-strand mispairing and unequal crossing-over events during DNA replication.