• 한국식품영양과학회지
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• 제32권4호
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• pp.506-512
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• 2003

복숭아 착즙액의 당도를 24$^{\circ}$Brix로 조절하여 $25^{\circ}C$에서 2주간 발효하여 제조한 후 15$^{\circ}C$에서 14주간 숙성 과정 중 복숭아주의 이화학적 성분 및 미생물의 변화를 살펴보았으며 한외여과 후의 복숭아주의 이화학적 특성의 변화를 관찰하였다. 총 세균수는 발효 초기 2.8$\times$$10^2$ CFU/mL에서 2주간의 발효 후에는 2.4$\times$$10^{7}$ CFU/mL로 증가한 후 숙성과정을 거친 후에는 7.0$\times$$10^3$ CFU/mL로 다시 감소하였다. 효모의 경우에는 발효 초기 3.4$\times$$10^2$ CFU/mL에서 발효 후에는 2.4$\times$$10^{7}$ CFU/mL로 증가한 후, 숙성과정을 거친 후에는 4.0$\times$$10^4$ CFU/mL로 역시 감소하는 경향을 보였다. 탁도, 총당, 환원당, 고형물 함량과 b값은 발효가 진행됨에 따라 감소하였고, 산도, 알코올 함량, L값과 a값은 증가하는 경향을 나타내어 발효가 완료된 후의 산도는 0.41%, 알코올 함량은 8.2%의 값을 보였다. 숙성과정 중에는 알코올 함량이 증가한 반면 환원당 함량은 감소하였다. 복숭아주를 0.45 $\mu\textrm{m}$ nitrocellulose 미세여과막을 이용하여 여과한 후 재질과 공경이 서로 다른 한외여과막을 사용하여 한외여과한 결과 Biomax 100K 막이 초기 flux가 79 liter/$m^2$/h(LMH)로 가장 높았으며 평균 flux도 가장 우수하여 한외여과공정의 최적 한외여과막으로 선정하였다. 한외여과에 의해 복숭아주 내에 존재하는 미생물은 완벽하게 제거되었으며 탁도와 알코올 함량은 약간 감소하였으나 그 이외의 이화학적 특성은 크게 변화하지 않았다. 복숭아주를 3$0^{\circ}C$에서 12주간 저장하였을 경우 저장기간동안 미생물이 전혀 검출되지 않았으며 이화학적 특성도 변화하지 않았다.

• Applied Biological Chemistry
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• 제46권3호
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• pp.201-206
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• 2003

사과 착즙액을 효모를 이용하여 발효시키는 과정에서 사과주의 발효패턴을 관찰하였으며 숙성과정 및 한외여과에 따른 미생물학적 변화와 이화학적 특성을 조사하였다. 사과 착즙액을 Saccharomyces cerevisiae KCCM 12224를 사용하여 $25^{\circ}C$에서 14일간 발효시킨 후 $15^{\circ}C$에서 14주간 숙성시킨 결과 발효기간 중 총세균과 효모는 각각 $1.4{\times}10^3$ CFU/ml, $4.3{\times}10^4$ CFU/ml에서 $2.8{\times}10^6$ CFU/ml, $1.2{\times}10^7$ CFU/ml로 증가하였다. 숙성과정을 거친 후에는 총세균수는 $10{\times}10^5$ CFU/ml로, 효모수는 $1.2{\times}10^4$ CFU/ml로 감소하였다. 발효기간 중 당도는 $20.0^{\circ}Brix$에서 $8.5^{\circ}Brix$로, 환원당은 9.66%에서 6.44%로 감소한 반면, 알코올 함량은 7.0%로, 산도는 0.19%에서 0.24%로 증가하였다. 14주 동안 숙성하였을 때 pH, 산도, 당도는 큰 변화를 보이지 않은 반면, 환원당과 고형물 함량은 감소하였고 알코올 함량은 11.8%까지 증가하였다. 사과주를 $0.45\;{\mu}m$ nitrocellulose 미세여과막을 이용하여 여과한 후 재질과 공경이 서로 다른 한외여과막을 사용하여 한외여과한 결과 Biomax 100k 막의 초기 $flux(121.2\;liter/m^2/h)$와 평균 flux가 사용한 한외여과막 중에서 가장 높았다. 한외여과에 의해 사과주 내에 존재하는 미생물은 완벽하게 제거되었으며 탁도와 고형물 함량은 감소하였으나 그 이외의 이화학적 특성은 변화하지 않았다. 사과주를 $15^{\circ}C$에서 6주간 저장하였을 경우 저장기간동안 미생물이 전혀 검출되지 않았으며 이화학적 특성도 변화하지 않았다.

• The Korean Journal of Physiology
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• 제27권1호
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• pp.13-25
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• 1993

To study the regulation of amniotic fluid volume and electrolyte concentration by the Membranes surrounding the amniotic fluid, the rate of $Li^+$ disappearance from amniotic sac of expired fetuses were examined while increasing the amniotic volume and osmolarity in rabbits. After intraamniotic injection of 1 ml isosmotic saline (about 20% of the amniotic fluid volume) containing 15 mM LiCl and 0.5 g/L Censored, the time courses of $Li^+$ and Censored disappearance were determined. From there the $Li^+$ clearance through the extrafetal routes was estimated and compared with that obtained from living fetuses. The volume, $Na^+$ concentration and osmolarity of amniotic fluid were measured and their relationships with $Li^+$ disappearance were evaluated. The fellowing results were obtained: 1. The rate of disappearance from amniotic fluid of living fetuses during the first 30 minutes was strikingly higher for $Li^+$ than for Censored, suggesting that extrafetal routes exist. At 60 and 90 minutes, however, the disappearance rate of $Li^+$ was less than that of Censored, suggesting the possibility of $Li^+$ reentry through fetal urination. 2. The disappearance of $Li^+$ from the amniotic fluid of the expired fetus was substantial, although lower than that of living fetuses, throughout the experimental period. 3. The $Na^+$ concentration and the osmolarity of the amniotic fluid of expired fetus measured 30 minutes after an intraamniotic injection of isoosmotic saline showed wide variation, but thereafter they changed gradually towards the normal extracellular fluid level. 4. When the amniotic fluid was iso- or hyposmolar, the rate of $Li^+$ disappearance from the amniotic fluid of the expired fetuses showed little variation. However, when the amniotic fluid was hyperosmolar, the rate at 30 minutes was markedly lower than those of isosmotic or hyposmotic amniotic fluid. At 90 minutes, the rate of $Li^+$ disappearance in hyperosmolar fluid reached a similar level to the rate in isosmolar fluid. 5. The intraamniotic injection of 400 mOsm/L saline solution decreased the disappearance rate of $Li^+$ from expired fetuses, while the injection of mannitol into the maternal vein induced no significant change. From these results it is concluded that: 1) a significant amount of $Li^+$ may leave the amniotic fluid via filtration through the membranes surrounding the amniotic fluid, 2) during hyperosmolar challenge to amniotic fluid, osmotic bulk flow might counteract the filterable loss, and 3) $Li^+$ disappearance might continue even after the volume and osmolarity of the amniotic fluid have recovered to control values.

• 대한약리학회지
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• 제17권1호
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• pp.1-8
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• 1981

Mitochondria로 부터의 $Na^+$에 의한 $Ca^{++}$유리현상은 digitalis의 강심기전을 설명하는데 있어 세포내 $Ca^{++}$농도 증가기전을 설명할 수 있는 현상의 하나로 보여지므로 $Na^+$에 의한 $Ca^{++}$유리와 이러한 $Ca^{++}$유리가 반응액내 $Ca^{++}$ 존재 유무로 어떠한 변화를 받는지를 비교 검토하였고 steady state에서의 $Ca^{++}$ flux에 대한 $Na^+$의 효과를 관찰하였다. $Na^+$의 증가에 따라 mitochondria에 흡수된 $Ca^{++}$의 유리량과 유리율이 증가하였고, EGTA 1mM 투여로 반응액내 잔여 $Ca^{++}$을 없을 경우 $Ca^{++}$유리가 증가함을 보여, 반응액내 잔여 $Ca^{++}$이 $Na^+$에 의한 $Ca^{++}$유리를 억제하리하 믿어진다. 한편 steady state에서 unidirectionai $Ca^{++}$ influx가 $Na^+$에 의하여 감소되는 점으로 미루어, $Na^+$에 의한 $Ca^{++}$유리는 $Na^+$이 $Ca^{++}-Ca^{++}$ 교환을 직접 억제하여 $Ca^{++}$ influx를 감소시켜 나타나는 결과로 생각된다. $Na^+$에 의한 unidirectional $Ca^{++}$ influx의 억제는 $Ca^{++}-Ca^{++}$교환에 $Na^+$이 직접 작용하며, 또한 반응액내 $Ca^{++}$의 다소에 따라 $Na^+$에 의한 $Ca^{++}$ 유리정도가 변화되는 양상으로 미루어 보아 mitochondria의 $Ca^{++}$ 운반의 일부는 $Na^+$과 $Ca^{++}$이 상경적으로 작용하는 모종의 동일매개체에 의하여 이루어질 수 있으리라 생각된다.

• 대한치과보철학회지
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• 제36권1호
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• pp.64-80
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• 1998

The risk of cross-contamination in dental clinic is very high. Those who are engaged in dental clinic are exposed to various microorganisms in saliva and blood of patient. Potential possibility of cross-contamination of patient to patient, patient to dentist, dentist to laboratory technician always exist, which is important in the view of public health. It is well known that microorganisms may cause cross-contamination by suck-back of microorganisms into the water supply line or air supply line of dental unit and sprayed back into the next patient's oral cavity. The majority of microorganisms coming from dental unit are water microorganisms from the main water supply which have colonized the tube within the units and multiplied in the relatively warm and stagnant conditions. The purpose of this study is to measure the extent of microbial contamination of dental unit and ultrasonic scaler, to evaluate that dental unit water supply is suitable for drinking water, and to assess the effect of flushing on reduction of microbial contamination of dental unit and ultrasonic scaler. In the first experiment, water samples(50ml) from 20 dental units and 10 ultrasonic scalers in Seoul National Univ. Hosp. were tested for the presence of coliform. The samples were filtered by membrane filtration technique.(Microfil system, Millipore Co. U. S. A.) The filter was then placed onto MacConkey agar plate and the plates with filter on it were incubated aerobically at $37^{\circ}C$ for 5 days. The colors and shapes of colonies were examined if those were coliform. To verify the presence of coliform, the colonies were inoculated into phenol red lactose broth and incubated aerobically at $37^{\circ}C$ for 2 days. The fomation of gas was observed. In the second experiment, water samples from 20 handpieces, 10 ultrasonic scalers and 30 A/W syringes after 0, 2, 4, 6 min. flushing respectively were taken. $200{\mu}l$ water samples were spreaded on Brain Heart Infusion agar plate and the plates were incubated aerobically at $37^{\circ}C$ for 5 days. The number of colony was counted. The results obtained were summarized as follows 1. The water from dental unit and ultrasonic scaler was not suitable for drinking water. 2. No coliform was founded in dental unit and ultrasonic scaler water supply. 3. The number of colony of dental unit and ultrasonic scaler was highest in the group of o min. flushing(p<0.05). 4. There was no statistically significant difference in the extent of microbial contamination among handpiece, ultrasonic scaler and A/W syringe (p>0.05). 5. The number of colony was lowest in the group of 4 min. flushing, but there was no statistically significant difference among 2, 4, 6 min. flushing groups.(p>0.05) 6. It is recommended to flush dental unit water line for 4 min. after use on each patient.

• 대한핵의학회지
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• 제23권1호
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• pp.71-83
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• 1989

For the development of $^{99m}Tc-labelled$ antimony sulfide colloid and hydroxyethyl starch, various experiments such as preparation of colloid, control of the distribution of particle size, establishment of labelling conditions, determination of labelling yield and radiochemical purity, examination of stability, and organ imagings of rabbits etc. were carried out. 1) Antimony sulfide colloid was readily prepared by the reaction of aqueous solution of antimony potassium tartrate with hydrogen sulfide generated by treating ferrous sulfide with dilute sulfuric acid. The colloid could be stabilized by adding small amount of polyvinylpyrrolidone. 2) Electron microscopy analysis exhibited the distribution of colloid size in the range of $1\sim15nm$ with a major portion of 9 m. The colloid solution was sterilized by membrane filtration $(0.2{\mu}m)$ and then stored at $4^{\circ}C$. This sterilized colloid was so stable that it was usable at least for one year. 3) The antimony sulfide colloid was labelled by adding sodium $pertechnetate-^{99m}Tc$ solution to the reaction vial, followed by adding hydrochloric acid and then boiled for 30 min. The optimal pH of the reaction mixture was found to be in the range of $1.3\sim1.4$. Instant thin layer chromatography (ITLC) analysis showed high labelling yield of above 99.5%. This labelled colloid maintained high radio-chemical purity of above 99% until 10 hours after labelling. 4) Animal studies showed high uptake of $^{99m}Tc-Sb_2S_3$ colloid at lymph vessels and nodes indicating a suitable agent for lymphoscintigraphy. Satisfactory results were also abtained in other clinical studies. 5) Hydroxyethyl starch (HES $0.6\sim1.0%$) was labelled with $Na^{99m}TcO_4$ in the presence of $SnCl_2$ with high labelling yield of above 99.5%. The optimal pH of the reaction mixture was in the range of $1.8\sim2.0$. $^{99m}Tc-HES$ maintained high radiochemical purity of above 99% until 10 hours after labelling. 6) Animal studies showed that $^{99m}Tc-HES$ migrated more rapidly from the injection sites into the lymph vessels than $^{99m}Tc-Sb_2S_3$ colloid while less amount of the former was uptaken at lymph nodes than that of the latter. Similar phenomenon was also observed in other clinical studies. As a result, $^{99m}Tc-Sb_2S_3$ colloid was found to be more effective lymphoscintigraphic agent than $^{99m}Tc-HES$.

• 자원환경지질
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• 제33권6호
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• pp.505-517
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• 2000

This study was undertaken to provide a drinking water quality on the basis of physicochemical properties. In this study, the 25 samples of supply waters of the Taejon area were sampled twice (February and August in 1999). Hydrochemistry of the supply water belongs to the $Ca^{2＋}$-${HCO_3}^{-1}$ type, whereas the supply water was characterized by the relatively significant enrichment of ${Ca}^{2+}$, ${Na}^{2+}$, ${K}^{2+}$, ${Cl}^{2+}$ ions and heavy metals compared to the original water from the Daecheong lake. Generally, the supply water has a mean values for $10.7^{\circ}C$ of temperature, 6.86 of pH, -12 mV of Eh, 88 ${\mu}S$/cm of EC and 70.379 mg/l of TDS in February, whereas the waters of the same sites in August are a slightly high temperature ($26.1^{\circ}C$), TDS (78.069 mg/l) and extremely high EC (442 ${\mu}S$/cm) value. These values are similar with physicochemical properties of the original lake water depending on the seasonal differences. Results of speciation calculation indicate that potentially toxic ions might exist mainly in the forms of free metal (${Cu}^{2+}$ or ${Zn}^{2+}$) and a small amount of ${CO_3}^{2-}$and ${OH}^{-}$in the supply water. The water seemed to be in equilibrium with kaolinite field of the normal stability diagrams for the natural water. Based on enrichment parameter of the supply water normalized by original lake water composition, the average value of those parameter can be calculated with nearly 1.00, but the those values for Cu＋Zn possible source of decrepit pipe lines are 126.75 in February and 115.63 in August samples. The parameter values varied with sampling sites, however, do not exceed by chemistry of drinking water standard. Solid compounds remained on the membrane filter papers after filtration are adhered to pale yellow or yellowish brown colored dissolved solids and precipitates, which are coated by 0.02 to 0.35 mm thick per 500 ml with colloidal particles of about 1 to 2${\mu}m$ size. The particles are mainly Fe-Cu-Zn compounds and partly detected to Mn and Pb.

• 자원리싸이클링
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• 제20권3호
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• pp.28-39
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• 2011

본 고는 토양세척-폐수처리-처리수재활용의 친환경공정순환시스템에 대한 이론적인 조사와 국내외 실제적용사례를 조사하였다. 광산폐기물에 함유된 이동성과 용해성이 큰 비소 및 독성 중금속들은 주변 토양 및 지하수를 오염시킬 수 있기 때문에 오염토양은 적절하게 처리되어야 한다. 국내외에서 비소와 중금속 오염토양에 시도되었거나 성공한 기술은 반응벽체(reactive barriers) 및 복토(encapsulation), 고형화(solidification)/안정화(stabilization), 토양세척(soil washing), 식물정화기법(phytoremediation) 등이 있는데, 이 중 본고는 용액을 사용하여 토양으로부터 오염물질들을 제거하는 물리화학적인 기술인 토양세척에 대해 다루었다. 토양세척의 한가지 큰 문제점은 처리 후에 폐수가 대량으로 발생한다는 것이고, 이 폐수에는 세척용액의 리간드와 결합한 오염물질들이 함유되어 있기 때문에 추가적인 처리공정이 필요하다. 그 처리기술에는 오염물질과 세척용액의 특성에 따라 다양한 물리, 화학, 생물학적 처리가 있는데, 그 중에서 화학적 처리기술인 침전/공동침전법, 멤브레인막여과법, 흡착처리법, 이온교환처리법, 동전기처리법에 대해서 본문에 자세히 언급하였다. 마지막으로 각각의 처리법에 따라 실제 토양세척폐수처리 및 재활용에 관한 최근 국내외 연구사례 대해 소개하였고, 이러한 기술들을 바탕으로 토양세척폐수발생문제를 해결하고 수자원절감을 통한 공정의 전반적인 비용효과를 높일 수 있을 것이다.

• 한국수산과학회지
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• 제29권2호
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• pp.246-255
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• 1996

연속식 3단계 막반응기로부터 각 단계별로 분리한 가자미피 젤라틴 가수분해물의 항산화성을 측정한 결과, 2단계 가수분해물의 항산화력이 가장 뛰어날 뿐만 아니라, 천연항산화제인 $\alpha-tocopherol$보다 $10\%$ 정도의 높은 항산화력을 나타낸 반면, 1단계 및 3단계 가수분해물은 $\alpha-tocopherol$보다 오히려 $10\~15\%$ 정도 낮은 항산화력을 보였다. 가수분해물의 첨가한 농도에 따른 항산화성은 유지중량에 대해 $1.0\%(w/w)$로 첨가한 농도에서 최대 항산화력을 나타내었다. 한편, 천연항산화제인 $\alpha-tocopherol$과 합성항산화제인 BHT와의 상승효과를 검토한 결과, 각 단계별 가수분해물은 $\alpha-tocopherol$과 우수한 상승효과를 관찰할 수 있었으며, 그 중 2단계 가수분해물의 상승효과가 가장 강하였다. 또한 항산화성이 가장 뛰어난 2단계 가수분해물로부터 gel column, ion exchange column 및 ODS column을 사용하여 항산화력이 특히 우수한 부분만을 분리한 단일 펩티드를 간세포에 첨가하여 세포생존율에 미치는 효과를 관찰한 결과, TBHP의 독성에 대해 펩티드 첨가구가 무첨가구에 비해 세포생존을 연장시켰으며, lipid peroxidation측정에서도 세포의 산화를 억제함으로써 세포의 생존율을 높였다.

• 약학회지
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• 제34권4호
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• pp.238-243
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• 1990

Pharmacokinetic characteristics of recombinant human interleukin-2 (rH IL-2) wre studied in the rat. First, different doses of rH IL-2 ranging from 6,400 to 1,600,000 U/kg were injected intravenously and the effect of dose size on the pharmacokinetics was examined. There was no dose dependency in the pharmacokinetics of rHIL-2 in the dose range of 6,400-40,000 U/kg. But at the dose of 1,600,000 U/kg, there was a severe hemolysis throughout the experiment and the pharmacokinetic parameters such as Vdss and CLt were significantly increased compared to those obtained from lower doses. It also showed that this drug is hardly distributed to the peripheral tissues and hardly eliminated from the body, since the valume of distribution (Vdss) and total body clearance (CLt) were 45-75 ml/kg and 1-2 ml/min/kg, respectively. The Vdss is close to the actual plasma volume and the CLt is less than glomerular filtration rate (GFR). Therefore it seemed that rH IL-2 is distributed only in the plasma pool and hardly filtered in the kidney due to its very large molecular weight. Second, rH IL-2 was administered to the rat via several routes such as hepatic portal vein (PV), intraperitoneal (IP), peroral (PO) and intranasal (IN) routes. The bioavailabilities (BA) of PV, IP, PO and IN routes were 96.8, 4.9, 0 and 0.1%, respectively. The addition of some nasal absorption enhancers such as taurocholate, taurodeoxycholate, glycocholate and glycodeoxycholate did not increase the BA of intranasaly administered rH IL-2. The result is contrast to the effect of these bile salts on the nasal absorption of ${\alpha}-inteferon$. Considering it together with the pharmacokinetic parameters, very large molecular weight of rH IL-2 seemed again to be the cause to very poor membrane permeability.