• The Korean Journal of Physiology and Pharmacology
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• v.9 no.5
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• pp.269-273
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• 2005

In horizontal cells (HCs) that were freshly dissociated from goldfish retina, two types of voltagedependent calcium currents ($I_{Ca}$) were recorded using a patch-clamping configuration: a transient type current and a sustained type current. The cell was held at -40 mV, and the prepulse step of -90 mV was applied before command pulse between -65 and +55 mV. The transient $Ca^{2+}$ current was activated by depolarization to around -50 mV from a prepulse voltage of -90 mV lasting at least 400 ms and reached a maximal value near -25 mV. On the other hand, the sustained $Ca^{2+}$ current was induced by pre-inactivation for less than 10 ms duration. Its activation started near -10 mV and peaked at +20 mV. $Co^{2+}$ (2 mM) suppressed both of these two components, but nifedipine ($20{\mu}M$), L-type $Ca^{2+}$ channel antagonist, blocked only the sustained current. Based on the activation voltage and the pharmacolog$I_{Ca}$l specificity, the sustained current appears to be similar to L-type $I_{Ca}$ and the transient type to T-type $I_{Ca}$. This study is the first to confirm that transient type $I_{Ca}$ together with the sustained one is present in HCs dissociated from goldfish retina.

• Journal of Ginseng Research
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• v.39 no.2
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• pp.169-177
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• 2015

Background: Ginsenoside Rd (GSRd), one of the most abundant ingredients of Panax ginseng, protects the heart via multiple mechanisms including the inhibition of $Ca^{2+}$ influx.We intended to explore the effects of GSRd on L-type $Ca^{2+}$ current ($I_{Ca,L}$) and define the mechanism of the suppression of $I_{Ca,L}$ by GSRd. Methods: Perforated-patch recording and whole-cell voltage clamp techniques were applied in isolated rat ventricular myocytes. Results: (1) GSRd reduced $I_{Ca,L}$ peak amplitude in a concentration-dependent manner [half-maximal inhibitory concentration $(IC_{50})=32.4{\pm}7.1{\mu}mol/L$] and up-shifted the current-voltage (I-V) curve. (2) GSRd ($30{\mu}mol/L$) significantly changed the steady-state activation curve of $I_{Ca,L}$ ($V_{0.5}:-19.12{\pm}0.68$ vs. $-6.26{\pm}0.38mV$; n = 5, p < 0.05) and slowed down the recovery of $I_{Ca,L}$ from inactivation [the time content (${\zeta}$) from 91 ms to 136 ms, n = 5, p < 0.01]. (3) A more significant inhibitive effect of GSRd ($100{\mu}mol/L$) was identified in perforated-patch recording when compared with whole-cell recording [$65.7{\pm}3.2%$ (n = 10) vs. $31.4{\pm}5.2%$ (n = 5), p < 0.01]. (4) Pertussis toxin ($G_i$ protein inhibitor) completely abolished the $I_{Ca,L}$ inhibition induced by GSRd. There was a significant difference in inhibition potency between the two cyclic adenosine monophosphate elevating agents (isoprenaline and forskolin) prestimulation [$55{\pm}7.8%$ (n = 5) vs. $17.2{\pm}3.5%$ (n = 5), p < 0.01]. (5) 1H-[1,2,4]Oxadiazolo[4,3-a]-quinoxalin-1-one (a guanylate cyclase inhibitor) and N-acetyl-$\small{L}$-cysteine (a nitric oxide scavenger) partly recovered the $I_{Ca,L}$ inhibition induced by GSRd. (6) Phorbol-12-myristate-13-acetate (a protein kinase C activator) and GF109203X (a protein kinase C inhibitor) did not contribute to the inhibition of GSRd. Conclusion: These findings suggest that GSRd could inhibit $I_{Ca,L}$ through pertussis toxin-sensitive G protein ($G_i$) and a nitric oxide-cyclic guanosine monophosphate-dependent mechanism.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.771-774
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• 2003

Passivation Ledge's device is taken possession on one-side to the Emitter in this Paper. contact used in this paper Pt as Passivation Ledge of device to use Schottky Diode which has leitmotif, It is accomplished Current Modulation that we wish to do purpose using this device. Space Charge acts as single device which is becoming Passivation to know this phenomenon. This device becomes floating as well as Punched-through. V$_{L}$ (Voltage for Ledge) = - 0.5V ~ 0.5V variable values , PD(Partially Depleted ; Λ＞0), as seeing FD(Fully Depleted ; A = 0) maximum electric current gains and Gummel Plot of I-V characteristics (V$_{L}$ = 0.1/ V$_{L}$ = -0.1 ). Becomming Degradation under more than V$_{L}$ = 0.1 , less than V$_{L}$ =-0.05 and Maximum Gain(=98.617076 A/A) value in the condition V$_{L}$ = 0.1. A Change of Modulation is electric current gains by using Schottky Diode and Extrinsic Base PN Diode of Passivation Ledge to Emitter Depletion Layer in HBT of Gummel-Poon I-V characteristics and the RF wide-band electric current gains change the Modulation of CE(Common-Emitter) amplifier description, and it had accomplished Current Gain Modulation by Ledge Bias that change in high frequency and wide bands. wide bands.s.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.3
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• pp.196-202
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• 2006

Treatment of hepatitis B virus (HBV) with lamivudine is effective in suppressing virus replication and results in reduced inflammatory activity. However the most troublesome problem of lamivudine treatment is the emergence of lamivudine-resistant strains with amino acid substitution in the YMDD motif of DNA polymerase gene during the treatment. The aim of this study was to determine the mutation of YMDD motif (codon 552) and codon 528 in chronic HBV patients with lamivudine therapy using PCR-direct sequencing and to investigate the relationship between lamivudine mediated HBV mutation and HBeAg. HBV DNA was extracted from serum samples of HBV patients and amplified by nested PCR with two sets of primer pairs selected in HBV DNA polymerase gene. Amplified PCR product was analyzed by 2% agarose gel electrophoresis and direct sequencing. HBV mutation was detected in 124 out of 207 samples (60%). Single mutation was 50.8% for M552I, 43.5% for M552V, 5.7% for M552I/V and the L528M mutation was 67.0%. Double mutation was 43.6% for M552V/L528M, 33.1% for M552I/L528(wild type), 17.7% for M552I/L528M and 5.6% for M552I/V/L528M. Serine mutation at YMDD motif (M552S) was not found and the L528M mutation frequently accompanied M552V type. In this study, the typical difference of frequencies for HBV mutation depending on HBeAg was not found. Moreover, the PCR-direct sequencing method used in this study might be a powerful tool for the mutation study in clinical reference laboratories with high volume.

• Molecules and Cells
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• v.24 no.3
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• pp.351-357
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• 2007

Regions (about 3.7-3.8 kb) of the mitochondrial genomes (rrnL-cox1) of two tardigrades, a heterotardigrade, Batillipes pennaki, and a eutardigrade, Pseudobiotus spinifer, were sequenced and characterized. The gene order in Batillipes was $\underline{rrnL}-\underline{V}-\underline{rrnS}-\underline{Q}-\underline{I}$-M-nad2-W-$\underline{C}-\underline{Y}$-cox1, and in Pseudobiotus it was $\underline{rrnL}-\underline{V}-\underline{rrnS}-\underline{Q}$-M-nad2-W-$\underline{C}-\underline{Y}$-cox1. With the exception of the trnI gene, the two tardigrade regions have the same gene content and order. Their gene orders are strikingly similar to that of the chelicerate Limulus polyphemus (rrnL-V-rrnS-CR-I-Q-M-nad2-W-C-Y-cox1), which is considered to be ancestral for arthropods. Although the tardigrades do not have a distinct control region (CR) within this segment, the trnI gene in Pseudobiotus is located between rrnL-trnL1 and trnL2-nad1, and the trnI gene in Batillipes is located between trnQ and trnM. In addition, the 106-bp region between trnQ and trnM in Batillipes not only contains two plausible trnI genes with opposite orientations, but also exhibits some CR-like characteristics. The mitochondrial gene arrangements of 183 other protostomes were compared. 60 (52.2%) of the 115 arthropods examined have the M-nad2-W-C-Y-cox1 arrangement, and 88 (76.5%) the M-nad2-W arrangement, as found in the tardigrades. In contrast, no such arrangement was seen in the 70 non-arthropod protostomes studied. These are the first non-sequence molecular data that support the close relationship of tardigrades and arthropods.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1638-1640
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• 1998

We describe the possibility of field application and the diagnosis method of winding deformation in the power transformers using L.V.I. test system. Any winding deformation will result in a change of capacitance between winding parts and passibly some change in the winding inductance. These changes will then result in a change in the responce to the applied pulse in both the magnitude and period of the resulting oscillations. And we discuss with respect to test result of model transformer and commercial transformer, appear good results with application possibility in field.

• Korean Journal of Microbiology
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• v.35 no.3
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• pp.237-241
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• 1999

Phenolic resin wastewater contained 41,000 mglI phenol, 2,800 mg/l fonualdehyde and various chlorinated phenolic compounds. Candida tropicalis PW-51 isolated [rom the natural enVlfooment was able to degrade 1,000 mg/l phenol in the presence of 100 mglI formaldehyde, but it took much time to degrade phenol with the increase of formaldehyde in phenolic resin wastewater. %en the phenolic resin wastewater was diluted to 1/40, the initial concentration of phenolic compounds (phenols) was 882 mglI and degraded to 81 mglI by C tfVpicalis PW-51 in batch culture. In a continuous biological treatment, the phenolic resin wastewater was diluted to 40 (745 mglI), 20 (1,356 mglI), or 10 (2,875 mglI) times. The removal efficiency of phenols in 1/40- and lI20-diluted phenolic resin wastewater was about 92%, but the phenols in 1!1O-diluted wastewater were not degraded. The remained phenols in wastewater were absorbed by a mixture of activated carbon and rice bran (1:1, v:v) in the process of absorption which was connected to the biological treatment. The total removal efficiency of phenols in 1!40~ and l/20-diluted phenolic resin wastewater was 99.9%.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.7
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• pp.56-61
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• 1997

I $n_{0.53}$G $a_{0.47}$As/I $n_{0.52}$A $l_{0.48}$As pseudomorphic high electron mobility transistor (P-HEMT) structures were grown on semi-insulating InP substrates by molecular beam epitzxy method. The hall effect measuremetn was used to measure the electrical properties and the photoluminescence (PL) measurement was used to measure the electrical properties and the photoluminescence(PL) measurement for optical propety. By the cross-sectional transmission electron microscopy (XTEM) investigation of the V and X shape defects including slip with angle of 60.deg. C and 120.deg. C to surface in the sampel, the defects formation mecahnism in the I $n_{0.52}$A $l_{0.48}$As epilayers on InP substrates could be explained with the different thermal expansion coefficients between I $n_{0.52}$A $l_{0.48}$As epilayers and InP substrate.d InP substrate.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.1
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• pp.93-98
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• 2001

The precise mechanism of set-point regulation in hypothalamus was not elucidated. Nitric oxide synthases(NOS) were detected in hypothalamus, however, the roles of NO in hypothalamus was not fully studied. So, we tested the effects of NO on body temperature because preoptic-anterior hypothalamus was known as the presumptive primary fever-producing site. NO donor sodium nitroprusside (SNP, 4 nmol, i.c.v.) elicited marked febrile response, and this febrile response was completely blocked by indomethacin (a cyclooxygenase inhibitor). But, ODQ (selective guanylate cyclase inhibitor, $50\;{\mu}g,$ i.c.v.) did not inhibit fever induced by SNP. The cyclic GMP analogue dibutyryl-cGMP $(100\;{\mu}g,\;i.c.v.)$ induced significant pyreses, which is blocked by indomethacin. $N^G-nitro-L-arginine$ methyl ester (L-NAME, non selective NOS inhibitor) inhibited fever induced by $interleukin-1{\beta}\;(IL-1{\bata},\;10\;ng,\;i.c.v.),$ one of endogenous pyrogens. These results indicate that NO may have an important role, not related to stimulation of soluble guanylate cyclase, in the signal pathway of thermoregulation in hypothalamus.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.3
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• pp.255-259
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• 1996

A study was carried out to investigate the action of central L-pheylalanine (Phe) and L-tyrosine (Tyr) on food intake of the chicken. In the first trial, Phe ($200{\mu}g/10{\mu}l$) or saline was acutely administered into the right lateral ventricle (i.c.v.) of chickens (5 birds per each group). Birds (4 birds per each group) were administered with the i.c.v. Tyr ($200{\mu}g/10{\mu}l$) or saline in the second trial. The brains of the birds were removed for catecholamine assy 30 min postadministration. Catecholamine concentrations were measured at specific sites of the brain (LH: lateral hypothalamus, PVN: paraventricular nucleus, and VMH: ventromedial hypothalamus). No significant effect of amino acids on the concentration of norepinephrine of brain sites investigated was detected. Food intake and rectal body temperature were also monitored for 6 h after central administrations of Phe, Tyr or saline (5 birds per each group). Both Phe and Tyr, up to $1mg/10{\mu}l$, failed to modulate food intake or rectal body temperature.