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        검색결과 1,263

        661.
        2009.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To enhance the embryo preservation technology and better application of embryo transfer technique to the field (dairy science or animal reproduction. etc.), we examined the viabilities of bovine embryos produced in vitro and in vivo after cryopreservation according to their developmental stage and thawing temperature. Bovine embryos from in vivo/vitro fertilization (Hanwoo) were examined at day 7, 8, and 9. Survival rates and total cell numbers of in vivo fertilized embryos were as follows: morulae 68.8% and ; blastocysts 80.5% and ; expanded blastocysts 77.4% and , respectively. Rates of embryo development for blastocysts and expanded blastocysts after thawing were significantly higher than that of morula stage embryos (p<0.05). While survival rates of in vitro fertilized embryos according to developmental stage showed no significant difference among groups (morula 67.9%; blastocyst 74.3%; and expanded blastocyst 79.4%), total cell numbers were significantly lower than those of other groups (morula ; blastocyst ; and expanded blastocyst ) For the viability according to thawing temperature, survival rate was higher in .
        4,000원
        666.
        2009.10 구독 인증기관·개인회원 무료
        During the last several years, the population of the ussur brown katydid, Paratlanticus ussuriensis has been highly increased at mountain-side orchards in Youngdong province in Korea. Nymphs and adults emerged one time per year from early May to August and cause a serious demage on the crop production. Adults oviposit eggs from July to September under the ground and eggs overwinter at diapause stage. However, the diapause duration P. ussuriensis is known to either one year or prolonged to additional years. The environmental cues, such as temperature, could be a critical to determine the diapause duration but the precise diapause mechanism of P. ussuriensis eggs is unclear. We demonstrated to determine the stage of diapause initiation during embryogenesis. Newly oviposited eggs were incubated for 60 days at two temperature conditions (20℃and 30℃). When the eggs were incubated at 20℃ those weights were not changed, but when they incubated at 30℃ those were increased from 15-days-old. Total RNA contents of eggs incubated at 30℃ were highly increased from the 15-days-old when they compared with those of eggs incubated at 20℃. In addition, total DNA contents of eggs were greatly higher when they incubated at 30℃. Our results suggest that early embryonic development was sensitive to high temperature and it was stimulated at 15-days-old. To determine the temperature response of embryonic development at molecular level we identified heat shock protein 70 (hsp70) gene of P. ussuriensis. Further analysis would conduct the gene expression rate of diapausing eggs on different temperature conditions by using real time RT-PCR technique and determine the molecular characteristics of P. ussuriensis egg diapause.
        670.
        2009.09 구독 인증기관 무료, 개인회원 유료
        Effects of Vegemil® containing soybean proteins and isoflavones on the growth and bone density of broiler chickens were investigated. One-week-old male and female Arbor Acres broiler chickens were fed on Vegemil® A containing 3% soybean proteins and 162 ppm isoflavones, instead of water, for 30 days and their growth indices (body weight, leg weight and femur length) and bone density were analyzed. The body weight gains in male and female chickens were increased by 15.6% and 31.7%, respectively, following feeding Vegemil® A compared to normal water. Vegemil® A increased leg weight as well as femur length of females by 22.9% and 15.0%, respectively. In addition, Vegemil® A feeding enhanced femoral bone density by 21.3% in comparison with water feeding. Therefore, it is suggested that Vegemil® A not only facilitates body growth, but also strengthens bone density of normal chickens, and that it could be a promising candidate for the improvement of infant growth and for the prevention of menopausal osteoporosis.
        4,000원
        671.
        2009.08 구독 인증기관·개인회원 무료
        As a laborsaving technique for weed control in a mountainous area in Japan, an integrated grazing system (IGS) for scattered small pastures has gathered attention recently. The objective was to estimate the loading doses of nitrate-N and ammonium-N in soils and agricultural water as result of this IGS approach compared with other land uses. As a result of time-course profiles of nitrate-N and ammonium-N in surface soils, the effect of applied fertilizers was emphasized more than the effect of manure produced by grazing animals. The nitrate concentrations of under-drainage from pasture were the same or lower than those of agricultural water below a vegetable field during grazing periods. It was considered that the IGS was at least the same or had a lower impact on N levels than that of vegetable fields.
        676.
        2009.06 구독 인증기관 무료, 개인회원 유료
        The present study was carried out to establish an animal model, displaying long-term learning and memory dysfunction, since single intracerebroventricular (icv) injection of amyloid β peptide (Aβ) causes a short-term memory impairment. Male ICR mice were fed a high-cholesterol diet (HCD) containing 3% cholesterol, 1% corn oil and 0.5% cholic acid, and 1 week later, icv injected with Aβ1-42 (5 μg/head). Learning/ memory function was assessed via passive avoidance performances 1 day and 2, 4, and 6 weeks after Aβ1-42 injection, in addition to blood biochemical analyses for lipid profiles and hepatic function. Total cholesterol, lowdensity lipoproteins and hepatic dysfunction parameters markedly increased, while high-density lipoproteins were reduced following HCD feeding. Whereas single injection of Aβ induced temporary memory loss 1 day after administration, exhibiting full recovery after 2 weeks, Aβ treatment in combination with HCD feeding lasted the learning/memory impairment up to 6 weeks. Therefore, it is suggested that hypercholesterolemia augments Aβ-induced memory loss, and that Aβ injection plus HCD feeding could be a long-term memorydeficit model suitable for long-term treatment with drugs or stem cells.
        4,000원
        677.
        2009.06 KCI 등재 구독 인증기관·개인회원 무료
        Human recombinant IL-32 induces the production of large amounts of several proinflammatory cytokines and chemokines, even in macrophage cell lines by activation of NF-κB and MAPK. The ability of IL-32 to potentiate inflammation is not the sole action of this cytokine. IL- 32 stimulates prostaglandin (PG)E2 in human PBMCs, which are pivotal in inflammation. The development of recombinant protein consisting of IL-32 is of great medical and industrial importance. Agrobacterium strains GV3101 harboring pCAMBIA1304 include IL- 32 vectors were used to infect the mushroom fruiting body pieces. For transformation experiments, fruiting body gill tissue pieces were vacuum infiltrated with the suspension of induced bacteria until the air had been completely purged. Mushroom mycelium appeared at the margins of the tissue pieces after 9 to 14 days on selection medium with hygromycin at 50㎍/㎖. Transformants PCR analyses confirmed that the IL-32 gene was into the genome of Pleurotus eryngii. The present results demonstrating the usefulness of the transgenic technique s in the genetic manipulation and improvement of mushroom.
        678.
        2009.06 KCI 등재 구독 인증기관·개인회원 무료
        Human GH (hGH) has been available over 40 years for the treatment of children with GH deficiency. Human growth hormone (hGH) is mainly produced in the somatotrophic cells of the pituitary in brain and is the product of the GH-N gene. Among the edible mushrooms, the king oyster mushroom (Pleurotus eryngii ) is one of the most popular mushrooms in Asia, Europe and North America. The increasing popularity of P. eryngii among consumers is due to its flavor, texture and shelf life. We report a modified Agrobacteriummediated method for the efficient transformation of hGH2 in Pleurotus eryngii . The binary vector pCAMBIA1304 was used for the initial transformation and detected by GUS and GFP. Infiltrated samples transformed with pCAMBIA1304 showed a wider GUS response than the co-cultivated in the 50㎍/㎖ hygromycin selection medium. This transformation technique offers new prospects for the production of useful protein in the genetically improved mushroom.
        679.
        2009.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We investigate the degeneracy in the pattern of central microlensing perturbations of a pair of planetary systems where the planets are located from the primary with projected separations in units of the Einstein radius s and s-1, respectively. From this, we confirm the fact that although alike, the patterns of central perturbations induced by a close (s < 1) planet and a wide (s > 1) planet are not identical and the degree of difference depends on the planet/primary mass ratio and the planet-primary separation. We find that the difference can be greater than 5% for planetary systems with lensing parameters located in the parameter space of (1/1.8 < lsl < 1.8, q > 5 x 10-3), (1/1.3 < lsl < 1/3, q > 1 x 10-3), and (1/1.2 < lsl < 1.2, q > 5 x 10-4), where q represents the planet/primary mass ratio. Although this range occupies a small fraction of the entire parameter space of planetary systems, we predict that the chance of resolving the close/wide degeneracy would not be meager considering that the planet detection efficiency is higher for planets with resonant separations (s ~ 1) and heavier masses. We also find that the differences between the perturbation patterns are basically caused by the effect of the planetary caustic. This explains the tendency of the perturbation difference where (1) the difference increases as the planet/primary mass ratio increases and the separation approaches the Einstein radius, (2) the region of major difference is confined within the region around the line connecting the central and the planetary caustics, and (3) a wide (close) planetary system has a more extended central perturbation region toward the (opposite) direction of the planet.
        4,000원
        680.
        2009.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We propose a diagnostic that can resolve the planet/binary degeneracy of central perturbations in caustic-crossing high-magnification microlensing events. The diagnostic is based on the difference in the morphology of perturbation inside the central caustics induced by a planet and a wide-separation binary companion. We find that the contours of excess exhibit a concentric circular pattern around the caustic center for the binary-lensing case, while the contours are elongated or off-centered for the planetary case. This difference results in the distinctive features of the individual lens populations in the residual of the trough region between the two peaks of the caustic crossings, where the shape of the residual is symmetric for binary lensing while it tends to be asymmetric for planetary lensing. We determine the ranges of the planetary parameters for which the proposed diagnostic can be used. The diagnostic is complementary to previously proposed diagnostics in the sense that it is applicable to caustic-crossing events with small finite-source effect.
        4,000원