• Journal of Microbiology
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• v.34 no.1
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• pp.37-37
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• 1996

The internal regions of nuclear small subunit rRNA from 6 plaeurotus species and 5 Pleurotus ostreatus strains were amplified by PCR and sequenced. The DNA sequences of 8 Pleurotus strains (P. ostreatus NFFA2, NFFA4501, NFFA4001, KFFA4001, KFCC11635, P florida, P. florida, P. sajor-cuju, P. pulmonarius, and P. spodoleucus) were idential, but P. cornucopiae differed from them in two bases out of 605 bases. However, p[hylogenetic analysis of the sequences by DNA-distance matrix and UPGMA methods showed that P. ostreatus NFFA2m1 and NFFA2m2, known as mutants of P. ostreatus NFFA2, belonged to anther group of Basidiomycotina, which is close to the genus Auricularia. The difference of the SSU rDNA sequences of P. cornucopiae from other Pleurotus species tested corresponds to the difference of mitochondrial plasmid type present in Pleurotus species as observed by Kim et al. (1993, Korean J. Microbiol. 31, 141-147).ishement of silencing at the HMR/hsp82 locus can occur in G1-arrested cells. Cell cycle arrest at G1 phase was achieved by treatment of early log a cell cultures with .alpha.-factor mating pheromone, which induces G1 arrest. The result suggests that passage through S phase (and therefore DNA replication) is nor required for re-establishing silencer-mediated repression at the HMNRa/HSP82 locus. Finally, to test whether de nono protein synthesis is required for re-establishment of silencer-mediated repression, cells were pretreated with cycloheximide (500 /.mu.g/ml) 120 min. It was apparent that inhibiting protein synthesis delays, but does not prevent, re-establishment of silencer-mediated repression. Altogether, these results indicate that re-establishment of silencer-mediated repression is not dependent on the DNA replication and has no requirement for protein synthesis.

• Korean Journal of Animal Reproduction
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• v.8 no.2
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• pp.100-109
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• 1984

This study was conducted to find out the changes of progesterone and estradiol-17$\beta$ levels in the serum of female Korean native goats during the reproductive stages such as the estrous cycle, pregnancy and periparturient period. Nine heads of female Korean native goats of 3 year old in average and weighing 35.7$\pm$1.4 kg were offered for the experiment. Blood samples were taken at 0, 1, 2, 5, 7, 10, 13, 15, 18 and 19 days after onset of estrus, and 1, 30, 60, 90, 120 and 149 days of pregnancy, and -5, -2, -1, 0, +1, +2 and +5 days of periparturient period where minus figures denote the days before paturition. The progesterone, estradiol-17$\beta$ in the serum samples were assayed by radioimmunoassay methods. The results of this study are summarized as follow: 1. The progesterone levels during the estrous cycles reached a peak level of 0.98$\pm$0.60ng/ml at 13 days after onset of estrus and decreased thereafter and were lower than 0.09$\pm$0.02mg/ml on the first day of estrus. 2. The estradioe17$\beta$ levels during the estrous cycles showed a peak level of 15.97$\pm$1.72pg/ml at onest of estrus, and decreased (5.41$\pm$0.51pg/ml-9.09$\pm$1.82pg/ml) during luteal phase. 3. The progesterone levels during the gestation period increased from day 1 and peaked at 90 days after mating and then decreased until 149 days. The peak level was 6.27$\pm$0.23ng/ml at 90 days. 4. The estradiol-17$\beta$ levels during the gestation period showed gradual increase, which were 9.03$\pm$0.88, 32.96$\pm$2.85, 46.03$\pm$2.42, and 54.06$\pm$1.64pg/ml on 30, 60, 90 and 120 dyas after mating respectively. 5. The progesterone levels measured from 5 days before the parturition to 5 days after showed the highest level at the shart of measurement (4.46$\pm$0.31ng/ml) and decreased gradually and bottomed out at one day post-partum and thereafter (0.24$\pm$0.02-0.45$\pm$0.06ng/ml). 6. The estradiol-17$\beta$ levels measured during the same periparturient period as progesterone showed increase to reach the peak level at 1 day before parturition and decreased rapidly thereafter (-5 dyas 69.46$\pm$3.62, -2 days 107.07$\pm$1.91, -1 days 137.83$\pm$7.54, 0 days 50.06$\pm$6.71 and +1 to +5 days 3.21-4.72 pg/ml).

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.345-360
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• 2000

The effects on CTC (T1) and CTC, Sulfathiazole and Penicillin Combination (T2) medication in feed through one life cycle of pigs, namely, weaning, mating, farrowing, lactation, growing, finishing and slaughter, were tested under local condition. In sow phase, productivity and the number of microflora in urine before and after medication of CTC were studied and average daily gain and feed conversion rate were checked during growing and finishing period. All pigs reached at 155 days old were slaughtered for pathological examination. 1. Litter size, farrowing rate and survival rate at birth were improved by CTC medication from weaning to 21th day after mating and mortality of piglet at weaning, 25 days after farrowing, was reduced in the CTC medication group, but no siginificant. 2. The number of microflora in the sow urine was changed with the medication at 200ppm of CTC in feed. In particular, the number of E coli, Samonella and Staphylococci were reduced by CTC medication. 3. The average daily gain and feed conversion rate of grower and finisher pigs was improved significantly in both treated groups, most in the high level CTC (T1) medicated group and was lowest in the control group. 4. The number of infected lungs was reduced not significant by both treatments (as % pneumonic lesions Co 66.7%, T1 47.1%, T2 31.4%) and the severity of lung lesions was significantly reduced by both high level of CTC and CTC combination medication in feed. 5. Although there were no statistical differences in atrophic rhinitis based on turbinate scores among the 3 groups, the number of mild and moderate (Grade 2 and 3) infections was higher in the control group (9/36) than in the treated groups (T1 2/34 & T2 4/35).

• Fisheries and Aquatic Sciences
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• v.21 no.5
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• pp.11.1-11.8
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• 2018

Interspecific hybridization experiments were conducted between the common seahorse Hippocampus kuda (male) and the slender seahorse H. reidi (female) during artificial rearing to develop a new aquarium fish with unique polyandrous mating. Molecular analysis via mitochondrial DNA (mtDNA) cytochrome b and nuclear DNA (ncDNA) ribosomal protein S7 gene supported the hybridization between the two species, and the hybrid also showed morphological characteristics of both species. Juveniles of H. kuda have dense melanophores on the whole body or only on the trunk and tail, whereas juveniles of H. reidi have thin melanophores on the whole body or present in stripes only along their prominent trunk and tail rings. However, all the hybrid juveniles had dense melanophores only on the tail, with the striped trunk rings, thus showing an intermediate pattern, and these patterns were limited to the fairly early stage of development (1-10 days old). In contrast, the two eye spines in the hybrid were apparent after 9 days old, which were not inherited from H. kuda (one eye spine), but from H. reidi (two eye spines). According to LOESS (local regression) analysis, the growth rate increased between 20 and 25 days, and the hybrids grew faster than H. kuda when they entered the explosive second phase of growth between 25 and 45 days for all the seahorses. This study highlights the hybridization between H. kuda and H. reidi may contribute to the improved taxonomic information of young seahorses.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.533-538
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• 2015

This study was conducted to examine the effect of salinity on the early embryonic development stage of boreal digging frogs (Kaloula borealis). An experiment was carried out with the eggs of K. borealis mating couples laid along the coastal zone of Jeju Island in June 2013. The salinity was set to 0, 1, 3, 5, and 7 ‰, respectively. The survival and growth of the larvae at various stages from the egg phase to the closing of their external gills phase were observed. In another experiment, tadpoles in internal gill stage were placed in solutions with salinity of 0, 1, 3, 5, and 7 ‰, respectively, and their survival rate and growth rate were observed, and then the results of the two experiments above were compared. The results showed that in egg and external gill stage, there was no significant difference in survival rate in 3 ‰ solution, though there was low survival rate in 5 ‰ solution. Further, all the eggs were dead in 7 ‰ solution, so it appeared that solutions with salinity of 5 ‰ or higher affect the survival of K. borealis in the early embryonic development. Larvae in the internal gill stage showed no significant difference in survival rate from the control group up to a salinity of 5 ‰, but when placed in a solution of over 7 ‰ salinity, the survival rate decreased. The growth rate also slowed down with the higher salinity. It appeared that in both the external gill stage and the internal gill stage in 5 ‰ solution, the growth rate decreased significantly compared to the control group. From this study it is concluded that higher salinity values have a significant impact on the survival and growth of the K. borealis larvae and this finding can be used to conserve K. borealis species that are decreasing in number due to the side effects of development in coastal areas.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.319-330
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• 1995

The influence of normal late pregnancy on insulin action and insulin secretion was studied in the Sprague-Dawley female rats. On 20th day after mating, intravenous glucose tolerance test(IVGTT) was performed in non pregnant control and pregnant rats. As results of IVGTT, glucose disappearance rate was not significantly different in both groups, but secretory response of insulin was significantly(p<0.05) increased in pregnant rat. And the ratio of insulin/glucose was significantly higher in pregnant rats, which means existence of insulin resistance. These insulin resistance was overcomed by increased secretory response of pancreatic insulin. Insulinogenic index(${\Delta}$ insulin/glucose - 5 min) was highly significantly (r=0.62, p<0.01) correlated with progesterone concentration. Glycogen level and amounts of $^{14}C$-glucose incorporated into glycogen after IVGTT were significantly(p<0.05) decreased in the liver, but were not changed significantly in soleus. Glycogen synthase activity of soleus and liver was not differ significantly in the both groups. Insulin binding at varying concentrations of insulin to crude membrane of pregnant liver was not significantly different from control. In conclusions, although these pregnant rats were normal glucose tolerance due to increased secretory response of insulin, that was correlated with progesterone concentration, pregnant rat had insulin resistance. The mechanisms of insulin resistance were not related to defect of insulin binding phase and glycogen synthase, but suggest pre-receptor and/or postreceptor phase.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.1
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• pp.31-37
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• 2000

This study was designed to identify the ultrastructural changes of mouse endometrium during peri-implantation period and obtain the fundamental information for the establishment of 3-dimensional culture system of mouse endometrial cells in vitro. The used female ICR mice ($6{\sim}8$ wks) were conducted on pregnant. The biopsies were obtained from whole uterus at cycle day 1 (D1) and day 5 (D5) after hCG injection and mating. The biopsies materials were fixed 2.5% glutaraldehyde and 1% osmium tetroxide. Subsequently, for observation using light and transmission electron microscopy (LM and TEM), they were dehydrated and embedded in Epon and the embedded biopsies were sectioned and stained. For scanning electron microscopy (SEM), the fixed specimens were dehydrated, dried and coated with gold. 1) For LM, the biopsied materials at D5 (late secretory phase) were appeared the extended stromal layer by increased connective tissues and the fully developed endometrial glands and vessels compared with D1 (early secretory phase). 2) For TEM, the mouse endometrium was consisted of 3-layers, a simple polarized columnar epithelial cells, basement membrane and stromal cells. At D5, the distribution of microvilli, endoplasmic reticulum, Golgi body, lipid and glycogen deposits, secretory granules and surface area of basement membrane were increased. 3) For SEM, the degree of folding and microvilli of surface of mouse epithelial cells was became more and more according to the process of secretory phase, and at D5, implantation time of mouse, the appearance of pinopodes as a specific marker of uterine receptivity was found. The uterine pinopodes of mouse were found in narrow sites at the luminal surface, irregularity and appeared the different stages in the same sample. Therefore, these results indicated that the mouse endometrium was experienced dramatic morphological changes during peri-implantation period.