• Korean Journal of Mathematics
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• v.16 no.3
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• pp.323-334
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• 2008

We define injective and projective representations of quivers with two vertices with n arrows. In the representation of quivers we denote n edges between two vertices as ${\Rightarrow}$ and n maps as $f_1{\sim}f_n$, and $E{\oplus}E{\oplus}{\cdots}{\oplus}E$ (n times) as ${\oplus}_nE$. We show that if E is an injective left R-module, then $${\oplus}_nE{\Longrightarrow[50]^{p_1{\sim}p_n}}E$$ is an injective representation of $Q={\bullet}{\Rightarrow}{\bullet}$ where $p_i(a_1,a_2,{\cdots},a_n)=a_i,\;i{\in}\{1,2,{\cdots},n\}$. Dually we show that if $M_1{\Longrightarrow[50]^{f_1{\sim}f_n}}M_2$ is an injective representation of a quiver $Q={\bullet}{\Rightarrow}{\bullet}$ then $M_1$ and $M_2$ are injective left R-modules. We also show that if P is a projective left R-module, then $$P\Longrightarrow[50]^{i_1{\sim}i_n}{\oplus}_nP$$ is a projective representation of $Q={\bullet}{\Rightarrow}{\bullet}$ where $i_k$ is the kth injection. And if $M_1\Longrightarrow[50]^{f_1{\sim}f_n}M_2$ is an projective representation of a quiver $Q={\bullet}{\Rightarrow}{\bullet}$ then $M_1$ and $M_2$ are projective left R-modules.

• Journal of Embryo Transfer
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• v.29 no.2
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• pp.177-182
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• 2014

Feline ovulation time after LH surge have not been defined because its LH surge is occurred by several times of coital vaginal induction and cat has relatively longer time between LH surge and ovulation compared with other mammalian species. This study was performed to investigate the feline ovulation time after LH surge that was induced by hCG injection for superovulation with PMSG. For superovulation, all cats were received an initial injection of PMSG (200 IU, i.m.) followed 80 hrs later with an injection of hCG (200 IU, i.m.). And then, sampling of both ovaries was surgically performed at each 6 different times (10, 18, 22, 26, 29, and 32 hrs) after hCG injection. Cumulus-oocyte-complexes (COCs) were collected from 2 sides of oviducts and ovaries were fixed for ovarian histology. Total 38 COCs were collected only at hCG 32 hrs and no COCs were shown at earlier 5 times. However, in the ovarian histology, corpus haemorrhagicum or corpus luteum was not shown in all groups including ovary at hCG 32 hrs that COCs were collected. In conclusion, it was suggested that feline ovulation was occurred at 29~32 hrs after LH surge and taken relatively long time for CL formation after ovulation.

• The Korea Journal of Herbology
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• v.28 no.1
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• pp.83-90
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• 2013

Objectives : Tetramethylpyrazine (TMP) is an active ingredient in Ligusticum wallichii and has a wide range of neuroprotection effects. This study investigated anti-neuroinflammatory effect of TMP on brain regions in intracerebroventricular (i.c.v.) lipopolysaccharide (LPS)-treated C57BL/6 mice. Methods : TMP was administered intraperitoneally at doses of 10, 20, and 30 mg/kg at 1 h prior to LPS (3 mg/kg) i.c.v. injection. mRNA level of pro-inflammatory cytokines, including tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin (IL)-$1{\beta}$ and IL-6, was measured in the cerebral cortex, hippocampus, and hypothalamus tissue using real-time polymerase chain reaction at 24 h after the LPS injection. Cyclooxygenase-2 (COX-2) positive cells in the hypothalamus was also observed using immunohistochemistry at 24 h after the LPS injection. Results : At a dose of 30 mg/kg TMP significantly attenuated up-regulation of TNF-${\alpha}$ and IL-$1{\beta}$ mRNA in the cerebral cortex and IL-$1{\beta}$ mRNA in the hippocampus. In the hypothalamus, doses of 20 mg/kg and 30 mg/kg TMP significantly attenuated up-regulation of TNF-${\alpha}$, IL-$1{\beta}$, and IL-6 mRNA induced by the LPS injection. In addition, TMP (30 mg/kg) significantly reduced the number of COX-2 positive cells in the hypothalamus. Conclusion : These results indicate that TMP has an anti-inflammatory effect on neuroinflammation, especially in the hypothalamus, induced by LPS i.c.v. injection and suggest that TMP-containing Ligusticum wallichii may play a modulatory role on the systemic responses following hypothalamic inflammation.

• Journal of fish pathology
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• v.16 no.3
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• pp.215-217
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• 2003

This study examined whether the connexin (Cx) is an essential protein during oocyte maturation in the ovary of the goldfish (Carassius auratus). In mature female goldfish ovaries, at late vitellogenic stage, human insulin-like growth factor-I (IGF-I; 20 M) and human chorionic gonadotropin(hCG; 20 IU/㎖) were injected. Twelve hr after the injection, mature female goldfish ovaries were removed and stored at -80C until analysis by RT-PCR. From the goldfish Cx43 cDNA sequence (GenBank accession number AB078505), two degenerate primers were designated. In vivo, 12 hr after the treatment with hCG, goldfish Cx43 mRNA expression level was increased, while the levels of IGF-I was not changed. Goldfish Cx43 mRNA expressed after, but not before the hCG treatment. These results suggest that Cx43 mRNA was judged to be a gene, which was transcribed during oocyte maturation induced by hCG.

• Journal of Embryo Transfer
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• v.13 no.1
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• pp.21-28
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• 1998

From September 1993 to August 1997, we treated ovarian disorders in 1,782 repeat breeder cows after diagnosis by ultrasound on 35 farms in Kyeong-ki do. The rates of ovarian appearance were 59.8% of CL group, 16.7% of ovarian atrophy or hypofunction, 15.4% of luteal cyst, 4.3% of follicular cyst and 3.7% of follicle group in diagnosis with rectal palpation and ultrasound. The results of treatment for ovarian disorders were 1,316 cows(73.8%) in estrus, 348 cows(19.5%) in non-detected and 118 cows(6.6%) in unidentified. The rates of PGF$_2$$\alpha$, GnRH and mineral vitamin complex treatment to estrus were 79.6, 69.2 and 50.3%. Two groups were treated with 5 ml PGF$_2$$\alpha$ intramuscular injection(I.M.) and 1.5 ml PGF$_2$$\alpha$ intraovarian injection(I.O.), and the results of 1.5ml PGF$_2$$\alpha$ I.0. were significantly higher than that of 5ml PGF$_2$$\alpha$ I.M. in inductiom estrus(p<0.05). The pregnant rates were 29.8% in total repeat breeder cows with ovarian disorders following diagnosis and treatment. In summary, rectal palpation and ultrasonography were proven to be useful tools of diagnosis and treatment in ovarian disorders, and it was also suggested that the response to treatment with PGF$_2$$\alpha$ I.0. was better than PGF$_2$$\alpha$ I.M.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.1
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• pp.1-5
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• 1991

Responsiveness of the testis to pregnant mare's serum gonadotropin (PMSG) was studied in immature Nili-Ravi buffalo bulls. Four month old bull calves weighing between 66 to 100 kg raised under uniform condition, were treated with 1000 IU PMSG or vehicle, daily, for six days. PMSG induced an increase in the size of the testis, enlargement of the seminiferous tubules and activation of the spermatogonia. The number of differentiated Leydig cells in the testis of gonadotropin treated animals increased considerably over that of the control testes. A significant increase in plasma testosterone concentrations was observed 24 h following the first injection of PMSG and the levels continued to increase until day 6. In vehicle treated animals plasma testosterone levels remained more or less at pretreatment values. The data suggest that buffalo bull testis is functionally responsive to gonadotropin at an early stage of prepubertal development.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.3
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• pp.430-436
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• 2019

Objective: This study identified angiotensin I-converting enzyme (ACE) inhibitory peptides in beef M. longissimus injected with thermolysin (80 ppm) and stored for 3 days at $5^{\circ}C$. Methods: Crude peptides (molecular weight <3 kDa) were obtained from the thermolysin hydrolysate and separated into seven fractions. Fraction V showing the highest ACE inhibitory activity was further fractionated, yielding subfractions V-15, V-m1, and V-m2, and selected for superior ACE inhibitory activity. Finally, twelve peptides were identified from the three peak fractions and the ACE inhibitory activity ($IC_{50}$) of each peptide was evaluated. Results: The Leu-Ser-Trp, Phe-Gly-Tyr, and Tyr-Arg-Gln peptides exhibited the strongest ACE inhibitory activity ($IC_{50}$ values of 0.89, 2.69, and 3.09 mM, respectively) and had higher concentrations (6.63, 10.60, and 29.91 pg/g; p<0.05) relative to the other peptides tested. Conclusion: These results suggest that the thermolysin injection process is beneficial to the generation of bioactive peptides with strong ACE inhibitory activity.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1469-1471
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• 1994

This paper describes the structure and electrical characteristics of a shorted anode p-i-n switch. The device showed a significant improvement in the threshold voltage-to-holding voltage ratio, which is due to the suppression of the hole injection from the anode and to the gold gettering at the anode side. The shorted anode devices with a $100{\mu}m$ channel length have a threshold voltage of 300 volts and a holding voltage of 5.5 volts.

• KSBB Journal
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• v.8 no.4
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• pp.328-335
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• 1993

A flow injection analysis(FIA) system was developed for the determination of cholesterol using immobilized cholesterol oxidase and cholesterol ester hydrolase. The enzymes were immobilized on controlled pore galas(CPG) by the glutaraldehyde method. The glass colunms packed with immobilized enzymes were found to contain 3-5 I.U. for each enzyme. A hydrogen peroxide sensitive electrode was contructed and applied to the FIA system. The operational conditions for FIA response were investigated and optimized with variation of sampling volume, flow rate and composition of carrier solution. The FIA response were linear upto 60 and 400mg/m1 for free cholesterol and cholesterol ester, respectively. All samples were analyzed with a good precision (<2.5% CV) and accuracy. 23 samples were mea sured succesively within about an hour. Intermittent assays of more than 500 times caused 50% decrease in response sensitivity.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.3
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• pp.203-217
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• 2019

The present study was designed to examine the effect of heme oxygenase-1 (HO-1) induction by cobalt protoporphyrin (CoPP) on the cardiac functions and morphology, electrocardiogram (ECG) changes, myocardial antioxidants (superoxide dismutase [SOD] and glutathione [GSH]), and expression of heat shock protein (Hsp) 70 and connexin 43 (Cx-43) in myocardial muscles in isoproterenol (ISO) induced myocardial infarction (MI). Thirty two adult male Sprague Dawely rats were divided into 4 groups (each 8 rats): normal control (NC) group, ISO group: received ISO at dose of 150 mg/kg body weight intraperitoneally (i.p.) for 2 successive days; ISO + Trizma group: received (ISO) and Trizma (solvent of CoPP) at dose of 5 mg/kg i.p. injection 2 days before injection of ISO, with ISO at day 0 and at day 2 after ISO injections; and ISO + CoPP group: received ISO and CoPP at a dose of 5 mg/kg dissolved in Trizma i.p. injection as Trizma. We found that, administration of ISO caused significant increase in heart rate, corrected QT interval, ST segment, cardiac enzymes (lactate dehydrogenase, creatine kinase-muscle/brain), cardiac HO-1, Hsp70 with significant attenuation in myocardial GSH, SOD, and Cx-43. On the other hand, administration of CoPP caused significant improvement in ECG parameters, cardiac enzymes, cardiac morphology; antioxidants induced by ISO with significant increase in HO-1, Cx-43, and Hsp70 expression in myocardium. In conclusions, we concluded that induction of HO-1 by CoPP ameliorates ISO-induced myocardial injury, which might be due to up-regulation of Hsp70 and gap junction protein (Cx-43).