• Korean Journal of Veterinary Research
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• v.34 no.4
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• pp.735-744
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• 1994

Catheters were placed into the external jugular veins of immature female rats. On the following day (day 28 of age), the animals were injected subcutaneously with pregnant mare serm gonadotropin(PMSG): 4IU(control) or 20IU(superovulation). Each animal was sequentially bled at Ohr and 12hr and subsequently at 6hr intervals until sacrifice at 72hr after PMSG. The superovulatory dose of PMSG significantly(P<0.05) increased the ovulatory response by 4.0 fold above controls. On the other hand, superovulated oocytes displayed considerably different stages of meiotic maturation: prophase I (14.7%), anaphase I (36.2%), telophase I (10.3%), metaphase I/II (32.4%), while in control rats a majority of the oocytes examined(94.0%) consistently showed a metaphase II configuration. Serum luteinizing hormone(LH) levels were determined by RIA. Both groups exhibited a similar time relationship with two distinct peaks: an initial slight rise at 0-18hr and a second sharp rise at 54-60hr. However, there was a marked change in the magnitude of LH levels between the two groups. In superovulated animals, prior to the second peak, overall LH levels were significantly(P<0.001) higher than controls. In contrast, at the peak occurring at 60hr, LH concentrations were significantly(P<0.001) reduced by 54% below that of control. Additionally, a maximum increase of mean ${\Delta}LH$ between two peaks was much less in superovulated as compared to control rats. The initial prolonged elevation of serum LH before 54hr in superovulated rats was found to result from actual cross-reaction of the injected PMSG with LH antibody in the assay, while a precipitous second elevation between 54hr and 60hr resulted primarily from an endogenous LH surge. This study clearly defines time-course features of serum LH in PMSG-treated rats. The overall results indicate that, following superovulatory treatment with PMSG, the increased ovulatory response is primarily associated with PMSG-derived intrinsic gonadotropin, and that the recovery of immature or asynchronously mature oocytes at ovulation may reult from the circulatory alteration of LH activity characterized by an initial prolonged elevation of serum LH and its subsequent attenuation.

• Journal of Plant Biotechnology
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• v.38 no.2
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• pp.176-185
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• 2011

Rice is one of the most important crop in the world, in particular for food resources. With its small genome size of 383 Mb, the Oryza sativa is a model plant for genome research. Indeed, it's grain provides human with a source of carbohydrates and proteins. Rice grain has relatively low protein contents (around 8%) compared to other legume seeds (around 40%). Osborne classified seed proteins into water soluble albumin, salt soluble globulin, alcohol soluble prolamin and acidic/alkaline solution soluble glutelin. Glutelin and prolamin are the major storage proteins in rice. For the gene expression study of seed storage proteins, we analyzed 33,192 EST clones at immature stages in a rice cultivar (Oryza sativa L. cv. 'Ilpum'). Based on the expression analysis, we cloned 11 glutelin genes and figured out the 8 genes are located on Chromosome 2. The expression of glutelin genes appears to be about 28.2% of total level in immature seeds. Interestingly, glu-04 is duplicated as inverted sequences on the same chromosomes as far 4.5 kb. Our results indicate that glutelin genes, evolutionarily, were replicated on the chromosome and thus expressed as specific manners. In a whole protein composition analysis, glu05 (type B7) contains the highest lysin contents (4.51%) among the 11 rice glutelin genes. It will be an interesting future work to increase lysin contents by the gene overexpressor strategy with the aim of improved diet nutritionally fortified.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.353-358
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• 2008

The bean pyralid, Omiodes indicatus (Fabricius), moulted 4 times during larval period. When temperature increased from 15 to 20, 25, and $30^{\circ}C$, the developmental period of immature stages was shortened; 18.2, 7.5, 5.0, and 4.1 days of egg period; 51.8, 20.0, 12.7, and 9.9 days of larval period; 29.5, 12.0, 8.0, and 5.9 days of pupal period, respectively. Adult longevity was 16.0, 14.7, 11.2, and 7.5 days at respective temperatures. A female adult layed 57.0, 63.3, 82.2, and 31.7 eggs in 3.7, 6.0, 5.8, and 3.0 days of oviposition period at the same temperature regimes, respectively. Field survey in 2006 and 2007 showed that leaf damage on paddy field and upland soybeans began to appear in mid July, reaching its peaks in mid August and late September. Adults of the bean pyralid appeared in mid July and peaked in late August and early October.

• The korean journal of orthodontics
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• v.36 no.4
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• pp.295-307
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• 2006

Objective: The purpose of this study was to compare the histological and biomechanical characteristics of self-tapping and self-drilling microscrew implants. Methods: 112 microscrew implants (56 self-drilling and 56 self-tapping) were placed into the tibia of 28 rabbits. The implants were loaded immediately with no force, light (100 gm), or heavy force (200 gm) with nickel-titanium coil springs. The animals were sacrificed at 3- and 5-weeks after placement and histologic and histomorphometric analysis were performed under a microscope. Results: All microscrew implants stayed firm throughout the experiment. There was no significant difference between self-drilling and self-tapping microscrew implants both in peak insertion and removal torques. Histologic examinations showed there were more defects in the self-tapping than the self-drilling microscrew implants, and newly formed immature bone was increased at the interface in the self-tapping 5-week group. There was proliferation of bone towards the outer surface of the implant and/or toward the marrow space in the self-drilling group. Histologically, self-drilling microscrew implants provided more bone contact initially but the two methods became similar at 5 weeks. Conclusion: These results indicate the two methods can be used for microscrew implant placement, but when using self-tapping microscrew implants, it seems better to use light force in the early stages.

• Journal of Embryo Transfer
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• v.31 no.3
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• pp.191-197
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• 2016

Historically, Korea old cattle had been consisted with various lines of coat color brindle, black and white-brown breeds or more. The two rare lines of black and white coat color are maintained for animal resources and preserved critically. The present study was carried out to evaluate potential usage of cysteamine supplementation during in vitro matration (IVM) and in vitro culture/production of embryo (IVP) by transvaginal ultrasound-guided follicle aspiration (Ovum Pick-Up: OPU) for the establishment of cryo-banking system. Immature slaughterhouse-derived cumulus-oocyte complexes (SL-COCs) were matured in IVM medium supplemented with 0, 0.1, 0.3 or 0.9 mM cysteamine, and then cultured in mSOF-BAS for 8 days after in vitro fertilization. The treatment of 0.1 mM cysteamine on SL-COCs showed higher rate of blastocyst, so OPU-derived COCs from rare breeds were matured in TCM media supplemented with or without 0.1 mM cysteamine, FSH and 5% FBS. The embryos were evaluated their developmental stages on day 8. During IVM, cysteamine treatment significantly increased the embryo production rate of slaughterhouse-derived COCs (19.6% vs. 30.5%). The presence of cysteamine during IVM of OPU-derived COCs from rare Korean cattle breeds (albino white and black line) also increased embryo production rates than those from SL-COCs (27.4% vs. 41.9% and 36.4%). With these results, cysteamine treatment during IVM is one of key factors IVP of blastocysts to establish banking system of endangered rare Koarean cattle with OPU derived transferable blastocysts.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.141-145
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• 2007

Maggot therapy (MT) has been re-introduced for non-healing wounds such as pressure sore, diabetic and necrotic ulcers, as well as infected surgical wounds, burn, and trauma injuries since early 1990s. For the production of sterile maggot of proper developmental stage, Lucilia sericata were studied on developmental periods of immature stages on liver agar medium under six different temperatures such as 15.4, 20.6, 22.5, 26.2, 29.1, and $33.0^{\circ}C$, and adult longevity and egg Production under $29^{\circ}C$. The periods of eggs and larvae of the 1st and the 2nd instars were shortest at $33^{\circ}C$ by 9.0, 14.0 and 18.6 hours, respectively. The periods of the 3rd instar larvae and pupae were shortest at $29.1^{\circ}C$ by 285.0 and 171.0 hours, respectively. Developmental zero point and total effective temperature far the development of each stage were calculated based on the developmental periods. Adults of both female and male lived more than one month. Females laid an average of 338.5 eggs through 2.7 times of egg laying throughout her lifetime.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.490-497
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• 2007

Odontoma is defined as a benign odontogenic tumor containing enamel, dentin as well as cementum and constitued 22% of all odontogenic tumors. Although the lesions are commonly asymptomatic, they may be discovered routine radiographic examination. Odontomas often cause disturbances in the eruption of teeth such as, impaction or delayed eruption, retention of primary teeth, or abnomalities in the position of the teeth such as tipping or displacement of adjacent teeth. Radiologically, odontomas manifest as a dense radiopaque lesion surrounded by a thin radiotransparent halo. However, in some cases, radiopacity was not quite clear and images of the teeth shadowed very tiny odontomas. And at early development stages of odontoma, calcification remains immature and is difficult to diagnose on radiographs. This suggests that when delayed eruption of the teeth is found, periapical radiographs should be taken to clarify whether any small area of radiopaque material exists. This case report shows tiny odontomas involving an impacted tooth and crowding and we remove the tiny odontoma surgically.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.306-312
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• 1998

Free sugar, organic acid, naringin, hesperidin and inorganic elements change of six varities of Cheju citrus fruits; Citrus natsudaidai, C. grandis, C. platymamma., C. sudachi, C. aurantiun and C. unshiu Marc. var. miyagawa by harvest date were investigated. Changes in free sugar of citrus fruits on the different harvesting stages and varieties showed a little differencies. The content of sucrose, glucose and maltose in citrus juice were $44.9{\sim}66.0%,\;15.7{\sim}25.7%\;and\;17.5{\sim}30.1%$, respectively. As the fruits were matured, free sugar was increased, but organic acid was decreased gradually. The major organic acids from the fruit juice were citric acid, malic acid and oxalic acid. Citric acid content exceeded 90%, oxalic acid ranged less than 3.58% and malic acid ranged $0.98{\sim}9.45%$ in total organic acids. Both naringin and hesperidin content showed markedly high in immature fruits, and in rind compare to fruit juice. Naringin and hesperidin content decreased as peel coloration progressed. It was estimated that fully matured fruits would be useful for making processed products, which lead to less turbity and less bitterness.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.287-293
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• 2005

This study was conducted to evaluate the effect of the conventional pesticide application system on the rice spider community based on the quantitative investigation of arthropod community in the rice fields in Saran area, Hwasung-si, Kyeonggi-do from 1996 to 1998. Spiders were the highest dominant group comprising over 90% of all natural enemies in their density, and showed very stable yearly occurrence. In these fiekds the mean density of spiders was about 10 individuals/$0.25m^2$ during the rice growing season, and three families including Lycosidae, Tetragnathidae and Linyphiidae were very abundant. The colonization of spiders occurred in early season and they showed rapid density increase in mid-season. They maintained the highest density to the late season and their density decreased at harvest season. In the years of the low rice pest occurrence, the disturbance effect on spider community by pesticides were less. Two dominant species, Pirata subpiraticus and Pachygnatha clerki, had different population dynamics; Pirata subpiraticus showed the rapid density increase in the mid-July, and most of them remained immature stages, however, in the case of Pachygnaths clerki population, they rapidly increased in the late August and most of them remained adult stage during the late growing season.

• Korean Journal of Animal Reproduction
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• v.17 no.2
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• pp.103-111
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• 1993

These experiments were undertaken to establish the optimal culture systems for in vitro maturation, fertilization and subsequently embryonic development of porcine immature follicular oocytes isolated from the ovary of slaughtered pigs. Porcine ovaries were brought to the laboratory from local slaughter house within 1 hour after slaughtering and cumulus oocytes complexes were recovered from antral follicles (3~5mm) with 23 gauge needle. To maturate follicular oocytes, cumulus oocytes complexes were washed three times with TCM-199 containing 25mM HEPES and incubated (39$^{\circ}C$, 5% CO2 in air) for 42hrs. Ejaculated and liquid storaged boar spermatozoa capacitated with different sperm capacitation methods and media were prepared forfertilizaing of matured follicular oocytes in vitro. Fertilization was performed by adding 5~10${mu}ell$ of capacitated spermatozoa containing 1~5$\times$105 sperm/ml to droplets. Eighteen to twenty-eight hours after sperm insemination, fertilized eggs were washed three times with culture media and transferred to the culture media. The fertilization rates of in vitro matured follicular oocytes cultured in B. O., TCM-HEPES, m-KRB, and TALP-II media were 61.3%, 83.0%, 88.9% and 89.2%, respectively. In addition, the polyspermy rates were 60.7%, 66.5%, 53.8%, and 43.9%, respectively. These data indicated that the highest of fertilization and the lowest of polyspermy rate was shown in TALP-II medium. Spermatozoa capacitated by caffeine, heparin, and percoll density gradient treatment in the 4 different media, the fertilization rates were 33.0~57.2%, 39.9~90.2%, and 52.6~92.8%, respectively, showing the lowest rate in caffeine treatment. The development rate of follicular oocytes, fertilized with the spermatozoa capacitated by caffeine, heparin, and percoll gradient in the TALP-II medium, upto 2 to 4-cell stages were 32.6%, 74.5% and 70.9%, respectively. Finally, fertilization rates of follicular oocytes cultured with follicular fluid containing medium from 10 to 100% were 61.2~94.1% and the rates (90~94%) with 10~20% follicular fluids were significantly higher than those (85.3%) of cultured in the media without follicular fluid. In addition, the rates of pronucleus formation were also higher in follicular fluid treated group (73.1~83.0%) than those (64.7%) of oocytes cultured without follicular fluid. The highest fertilization and pronucleus formation rates was found in oocytes cultured with 10% follicular fluid. These results suggest that the addition of heparin or percoll density gradient method is better capacitation method. Furthermore, the addition of porcine follicular fluid to the fertilization medium may improve the fertilization rates and formation of pronucleus.