• The Korean Journal of Physiology
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• 제19권1호
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• pp.49-59
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• 1985

The effects of anions on net accumulation of $(\rho-aminohippuric\;acid)$(PAH) were studied in rabbit kidney cortical slices. Experiments were carried while varying the major anionic composition of the incubation medium(replacement of $Cl^-$ by isethionate and $SCN^-$). The total replacement of $Cl^-$ with isethionate, $SO_4\;^{2-}$ and $SCN^-$ in the incubation medium decreased the 60-min slice-to-medium concentration(S/M) ratio of PAH to 60%, 40% and 50% of control value, respectively. The degree of inhibition in PAH accumulation by the replacement of isethionate and $SCN^-$ was increased with increasing of both preincubation and incubation time. The influence of isethionate and $SCN^-$ on PAH uptake was fully reversible. Both isethionate and $SCN^-$ increased the apparent Km value significantly with no change on the apparent Vmax value, suggesting a competitive inhibition on PAH uptake. And the inhibitory effect of $SCN^-$ on PAH uptake decreased with increase of pH in the incubation medium while that of isethionate increased with increase of pH. Intracellular water content, intracellular electrolyte concentration and oxygen consumption were not influenced by the replacement of $Cl^-$ with isethionate or $SCN^-$ in the incubation medium. These results suggest that both $isethionate^-$ and $SCN^-$ inhibit the PAH uptake by binding to some site necessary for normal PAH transport without affecting the cellular viability.

• Asian-Australasian Journal of Animal Sciences
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• 제7권1호
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• pp.75-81
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• 1994

To elucidate the relationship between steroidogenesis and sex differentiation in the duck, plasma, testicular and ovarian testosterone, estradiol-$17{\beta}$ and progesterone concentration in male and female embryo of day 11 to 27 (just before hatching) of incubation and in 1- to 7-day-old male and female duckling were investigated by radioimmunoassays. Plasma estradiol-$17{\beta}$ concentration in female embryos declined from very high at days 11 and 15 of incubation and remained at low levels after hatching. Male plasma estradiol-$17{\beta}$ concentration were always lower than those of the female throughout this period. Plasma testosterone and progesterone concentrations in both sexes were low during the embryonic stage, but then increased to peaks 3 days and 1 day after hatching, respectively. Estradiol-$17{\beta}$ contents were much higher in the left ovary than the right ovary or testes throughout the experimental period. The estradiol-$17{\beta}$ content of the left ovary was very high at day 15 of incubation, and decreased gradually thereafter. Both in right ovary and testes, estradiol-$17{\beta}$ contents were always low. Testosterone and progesterone contents in the left ovary were low from day 11 to 23 of incubation, and reached a peak 1 day after hatching. Progesterone content in the right ovary and testes were low levels over time period examined. Testosterone and progesterone contents were much higher in the left ovary than the right ovary and testes. The present results clearly demonstrate that the capacity of the embryonic left ovary of duck to synthesize estradiol-$17{\beta}$ and testosterone is much higher than that of the embryonic testis. It is suggested that estrogen secreted from the embryonic ovary earlier than day 15 of incubation has an important role in female sexual differentiation in the duck, and the sex of the avian species is basically male with homozygous sex chromosome (ZZ).

• 핵의학기술
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• 제14권1호
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• pp.138-142
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• 2010

PTH 측정은 체내 칼슘 및 이온화 칼슘의 수치와 함께 갑상선 절제술 후 저칼슘혈증을 예측하는 유용한 지표로서 임상에서는 신속한 결과 보고를 요구하고 있으나 검사반응시간이 길어 이에 상응하지 못하고 있다. 따라서 본 연구는 PTH 검사반응시간에 변화를 주어 신속한 결과 보고를 함으로서, 저칼슘혈증 예측 지표의 유용성을 평가하고자 한다. 2009년 7~8월까지 PTH를 검사한 환자들(n=131)을 대상으로 하였으며, 검사방법은 면역방사계수법으로 반응시간은 18${\pm}$2시간(Overnight), 0.5, 3, 6시간으로 구분하여 상관관계, 정밀도(10회 반복), 회수율을 측정하였다. 또한 조기 저칼슘 혈증 예측지표의 유용성을 평가하기 위해 민감도, 특이도, 양성예측도, 정확도를 비교 분석 하였다. 상관관계에서는 overnight을 기준으로 0.5시간은 $R^2$=0.987, 3시간은 $R^2$=0.993, 6시간은 $R^2$=0.996로 나타났다. 정밀도(%CV${\pm}$SD)에서 0.5시간은 $15.92{\pm}15.54$, 3시간은 $6.91{\pm}7.38$, 6시간은 $4.30{\pm}4.69$, Overnight은 $4.59{\pm}2.59$로 측정되었다. 회수율(%Mean${\pm}$SD)에서 0.5시간은 $96.8{\pm}5.44$, 3시간은 $102.6{\pm}4.35$, 6시간은 $100.7{\pm}2.56$, Overnight은 $102.2{\pm}5.98$로 측정되었다. 양성 예측치(cut-off point=15 pg/mL)를 기준으로 저칼슘혈증을 예측할 때, 0.5시간일 때 민감도 97.5% 특이도 96.0% 양성예측도 86.6% 정확도 84.7%였고, 3시간일 때 민감도 97.5% 특이도 100% 양성예측도 100% 정확도 97.5%였고, 6시간일때 민감도 97.5% 특이도 92.3% 양성예측도 92.8% 정확도 90.6%였다. Overnight법과 비교할 때 검사반응시간 3시간에서 98.3%로 가장 높은 일치율을 보였고, Kappa와 상관관계 또한 우수하였다. 이에 검사반응시간을 3시간으로 단축시켜 신속한 결과를 보고함으로써 환자의 저칼슘혈증을 조기에 예측하여 칼슘제 투여 등 적절한 조치를 취하여 환자의 증상발현을 막을 수 있는 유용한 지표로 활용될 것이다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권3호
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• pp.151-155
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• 2004

The bioremediation of water system contaminated with phenolic compounds having endocrine-disrupting activity, i.e. 2,4-dichlorophenol, 2,4-dichlorophenoxy acetic acid (2,4-D), and 2,4,5-trichlorophenoxy acetic acid (2,4,5-T), was investigated by using ozone oxidation and activated sludge treatment. Ozone oxidation (ozonation time: 30 min) followed by activated sludge treatment (incubation time: 5 days) was an efficient treatment method for the conversion of phenolic compounds in water into carbon dioxide and decreased the value of total organic carbon (TOC) up to about 10% of initial value. Furthermore, 2,4-D was dissolved in water containing salt, i.e. artificial seawater (ASW), and this water was used as model coastal water contaminated with phenolic compounds. The activated sludge treatment (incubation time: 5 days) could consume significantly organic acids produced from 2,4-D in the model costal water by the ozone oxidation (ozonation time: 30min) and decrease the value of TOC up to about 35% of initial value.

• Parasites, Hosts and Diseases
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• 제54권1호
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• pp.103-107
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• 2016

The objective of this study was to evaluate the effects of several different commercial disinfectants on the embryogenic development of Ascaris suum eggs. A 1-ml aliquot of each disinfectant was mixed with approximately 40,000 decorticated or intact A. suum eggs in sterile tubes. After each treatment time (at 0.5, 1, 5, 10, 30, and 60 min), disinfectants were washed away, and egg suspensions were incubated at $25^{\circ}C$ in distilled water for development of larvae inside. At 3 weeks of incubation after exposure, ethanol, methanol, and chlorohexidin treatments did not affect the larval development of A. suum eggs, regardless of their concentration and treatment time. Among disinfectants tested in this study, 3% cresol, 0.2% sodium hypochlorite and 0.02% sodium hypochlorite delayed but not inactivated the embryonation of decorticated eggs at 3 weeks of incubation, because at 6 weeks of incubation, undeveloped eggs completed embryonation regardless of exposure time, except for 10% povidone iodine. When the albumin layer of A. suum eggs remained intact, however, even the 10% povidone iodine solution took at least 5 min to reasonably inactivate most eggs, but never completely kill them with even 60 min of exposure. This study demonstrated that the treatment of A. suum eggs with many commercially available disinfectants does not affect the embryonation. Although some disinfectants may delay or stop the embryonation of A. suum eggs, they can hardly kill them completely.

• Toxicological Research
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• 제16권4호
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• pp.255-261
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• 2000

To investigate what kinds effect arsenic exert on the proliferation and differentiation of bone marrow cells to the neutrophilic granulocytes lineage cells, we treated sodium arsenite to murine bone marrow cells without or with the stimulation of G-CSF. When we added the various concentrations oj sodium arsenite to bone marrow cells without the stimulation of G-CSF for I, 3, 5 or 7 days, sodium arsenite did not make an any effect up to 2.5 $\mu\textrm{M}$$\mu\textrm{M}$$\mu\textrm{M}$$\mu\textrm{M}$$\mu\textrm{M}$$m\ell$ of G-CSF was induced by the co treatment of 12.5 $\mu\textrm{M}$

• 한국재료학회지
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• 제11권4호
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• pp.278-282
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• 2001

사파이어($\alpha$-$Al_2$$O_3$) 단결정에 있어 basal slip (0001)1/3<1120>의 부분전위의 재결합거동을 알아보기 위해 prism plane (1120)의 사파이어 재료를 사용하여 4점 곡강도 시험을 행하였다. 이 굽힘시험은 온도 $1200^{\circ}C$~$1400^{\circ}C$에서 그리고 응력은 90MPa, 120MPa, 150MPa에서 행하여졌다 굽힘시험 동안 basal전위가 이동하기 위해 잠복기가 필요하였다. 실험온도 범위내에서 잠복기의 활성화에너지는 5.6-6.0eV이었으며, 이 잠복기는 자체-상승운동으로 분해된 부분전위들이 재결합하는데 필요한 시간인 것으로 추정되었다. 한편, 이 활성화에너지는 $Al_2$$O_3$에 있어 산소의 자체 확산을 위한 에너지 (대fir 6.3eV)와 거의 일치하였다. 이 결과를 통하여, 두 부분전위들의 재결합은 부분전위사이 적층결함으로 산소 자체확산에 의해 제어되는 것으로 여겨진다.

• 대한수의학회지
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• 제30권4호
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• pp.487-497
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• 1990

This study was carried out to observe in vitro effect of praziquantel on the tegumental changes of Heterophyopsis continua with scanning electron microscope. Metacercariae were collected from the perch, Lateolabrax japonicus, by artificial digestion technique and fed to 2-week old chickens. Adult worms were recovered from small intestine of chickens 8 days after infection. For working solutions, praziquantel was diluted with TC199 medium at concentration of 0.01, 0.1. 1 and $10{\mu}g/ml$. To each petri dish containing 10ml of solution, 5~10 worms were introduced and incubated at $37^{\circ}C$. For the scanning electron microscopy(SEM), the worms were fixed in cold 2.5% glutaraldehyde, dehydrated in a series of graded ethanol and freeze-dried. Dried specimen was mounted on stub and coated with gold and observed in an SEM. The results were as follows: 1. Severe tegumental alterations were recognized by scanning electron microscope. Bleb formation of tegument was observed in 5 minute group and most pronounced on anterior tegument of worms. The number and size of blebs increased as incubation time prolonged. 2. The surface destruction was more pronounced at ventral margin between the oral and the ventral suckers. 3. The sensory papillae were slightly affected, but destruction of tegumental spine was not recognized. 4. The effect of praziquantel on the worm was found dependent on the concentration and incubation time, however, the effect was more dependent upon the incubation time.

• 한국전기전자재료학회논문지
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• 제16권7호
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• pp.573-578
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• 2003

Low temperature selective epitaxial growth of Si and SiGe has been obtained using an industrial single wafer chemical vapor deposition module operating at reduced pressure. Epitaxial Si and heteroepitaxial SiGe deposition with Ge content about 20 % has been studied as extrinsic base for self-aligned heterojunction bipolar transistors(HBTs), which helps to reduce the parasitic resistance to obtain higher maximum oscillation frequencies(f$\_$max/). The dependence of Si and SiGe deposition rates on exposed windows and their evolution with the addition of HCl to the gas mixture are investigated. SiH$_2$Cl$_2$ was used as the source of Si SEG(Selective Epitaxial Growth) and GeH$_4$ was added to grow SiGe SEG. The addition of HCl into the gas mixture allows increasing an incubation time even low growth temperature of 675∼725$^{\circ}C$. In addition, the selectivity is enhanced for the SiGe alloy and it was proposed that the incubation time for the polycrystalline deposit on the oxide is increased probably due to GeO formation. On the other hand, when only SiGe SEG(Selective Epitaxial Growth) layer is used for extrinsic base, it shows a higher sheet resistance with Ti-silicide because of Ge segregation to the interface, but in case of Si or Si/SiGe SEG layer, the sheet resistance is decreased up to 70 %.

• Journal of Microbiology and Biotechnology
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• 제29권4호
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• pp.548-557
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• 2019

Staphylococcus species have a ubiquitous habitat in a wide range of foods, thus the ability to identify staphylococci at the species level is critical in the food industry. In this study, we performed rapid identification of Staphylococcus species using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight mass spectrometry (MALDI-TOF MS). MALDI-TOF MS was evaluated for the identification of Staphylococcus reference strains (n = 19) and isolates (n = 96) from various foods with consideration for the impact of sample preparation methods and incubation period. Additionally, the spectra of isolated Staphylococcus strains were analyzed using principal component analysis (PCA) and a main spectra profile (MSP)-based dendrogram. MALDI-TOF MS accurately identified Staphylococcus reference strains and isolated strains: the highest performance was by the EX method (83.3~89.5% accuracy) at species level identification (EDT, 70.3~78.9% accuracy; DT, less than 46.3~63.2% accuracy) of 24-h cultured colonies. Identification results at the genus level were 100% accurate at EDT, EX sample preparation and 24-h incubation time. On the other hand, the DT method showed relatively low identification accuracy in all extraction methods and incubation times. The analyzed spectra and MSP-based dendrogram showed that the isolated Staphylococcus strains were characterized at the species level. The performance analysis of MALDI-TOF MS shows the method has the potential ability to discriminate between Staphylococcus species from foods in Korea. This study provides valuable information that MALDI-TOF MS can be applied to monitor microbial populations and pathogenic bacteria in the food industry thereby contributing to food safety.