• Parasites, Hosts and Diseases
• /
• 제46권2호
• /
• pp.65-70
• /
• 2008

Artemisinin-based combination therapy (ACT) is currently promoted as a strategy for treating both uncomplicated and severe falciparum malaria, targeting asexual blood-stage Plasmodium falciparum parasites. However, the effect of ACT on sexual-stage parasites remains controversial. To determine the clearance of sexual-stage P. falciparum parasites from 342 uncomplicated, and 217 severe, adult malaria cases, we reviewed and followed peripheral blood sexualstage parasites for 4 wk after starting ACT. All patients presented with both asexual and sexual stage parasites on admission, and were treated with artesunate-mefloquine as the standard regimen. The results showed that all patients were asymptomatic and negative for asexual forms before discharge from hospital. The percentages of uncomplicated malaria patients positive for gametocytes on days 3, 7, 14, 21, and 28 were 41.5, 13.1, 3.8, 2.0, and 2.0%, while the percentages of gametocyte positive severe malaria patients on days 3, 7, 14, 21, and 28 were 33.6, 8.2, 2.7, 0.9, and 0.9%, respectively. Although all patients were negative for asexual parasites by day 7 after completion of the artesunate-mefloquine course, gametocytemia persisted in some patients. Thus, a gametocytocidal drug, e.g., primaquine, may be useful in combination with an artesunate-mefloquine regimen to clear gametocytes, so blocking transmission more effectively than artesunate alone, in malaria transmission areas.

• Fisheries and Aquatic Sciences
• /
• 제12권4호
• /
• pp.331-338
• /
• 2009

This study presents physiological rates of respiration and excretion, clearance rate, and assimilation efficiency of the ark shell Scapharca broughtonii, determined during 2007 from specimens collected in Gamak Bay on the south coast of Korea. Physiological parameters were measured monthly under static, laboratory controlled conditions with ambient conditions, and measurements were performed seasonally in order to estimate scope for growth and its probable sources of variation. Temperature directly influenced respiration and excretion. Clearance rates showed a tendency to be low during May-August, which is a period of gametogenesis. Assimilation efficiency was not significantly different seasonally and was independent of the concentration of chlorophyll a. The scope for growth was negative during high-temperature months (July-August), reflecting the high temperature and low clearance rate, and had its highest positive values during spring and autumn. The energy budget or growth potential of bivalves has been applied to other economically important species. Data on the physiological parameters and scope for growth of S. broughtonii obtained in this study will be used to assess the carrying capacity for ark shell cultivation.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2004년도 학술대회지
• /
• pp.268-273
• /
• 2004

A study on experimental method of the model test for the impulse turbine is carried out. the wave simulator is used to reproduce the real wave condition. It controls two parameter correspond to wave height and wave frequency. The optimum design which is reported by T. Setoguchi is manufactured and tested for the validation of our test facilities. The comparison of model test show that our facilities produce little bit higher efficiency at maximum efficiency point. To increase the efficiency of turbine, the new rotor with negative tip clearance is designed and being tested.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1997년도 춘계학술대회 논문집
• /
• pp.244-249
• /
• 1997

Internal and external heat sources will cause to deform to machine elements in the contact joint of structure,which results in the change of contact pressure distribution different from initial assembly. Heat induced variations of contact pressure will change the static and dynamic properties such as contact stiffness,damping as well as contact heat conduction in the structure. In order to design and control the intelligent machine tool operating in variant conditions more sophisticatedly, the good prediction for the changes of prescribed propeties are strongly required especially in the contact elements adjacent to the rotational or linear bearing This paper presents some computational and experimental results in regard to static and dynamic characteristics of the press-fitted bush and shaft assembly which is a model of the bearing innerrace and shaft assembly. In the condition of heat generation on the outer surface of the bush,the effects of changes in the negative clearance and the heat flux on pressure distribution and dynamic properties are investigated. Results of this study show that the edge effect of the bush and the initial clearance have effects on the transient dynamic characteristics significantiy.

• Journal of Applied Biological Chemistry
• /
• 제55권2호
• /
• pp.109-115
• /
• 2012

본 연구의 목적은 간 손상을 유발시킨 백서에서 돈태반 가수분해물의 경구 투여가 간 기능 개선에 효과가 있는지를 조사하는 것이다. 사염화탄소를 피하주사하여 간 손상을 유발한 백서를 4군으로 나누어 DMSO(음성대조군), 저용량과 고용량(500과 1000 mg/kg 체중) 돈태반 가수분해물, silymarin (80 mg/kg 체중; 양성대조군)을 3주간 경구 투여하였다. 정상대조군은 사염화탄소 대신 용매인 옥수수 기름만을 피하주사하였다. 3주 후에 간과 지라의 질량은 음성대조군에 비해 농도 의존적으로 돈태반 가수분해물과 silymarin 투여군이 더 높았다(p<0.05). 제거율을 계산하여 간의 기능을 나타내는 bromosulfalein (BSP)를 주입하였을 때 간에서의 제거율은 음성대조군에 비해 돈태반 가수분해물의 복용량에 비례해서 증가하였고, 특히 고용량 돈태반투여군은 silymarin군과 유사한 값을 나타내었다. 이 결과 혈청내 BSP 농도는 돈태반투여군과 silymarin군에 비해 음성대조군에서 더 낮았다. 모든 군에서 간 기능의 지표인 혈청 AST와 ALT의 농도는 시간이 지남에 따라 감소하였는데, 돈태반 가수분해물과 silymarin 투여는 음성대조군에 비해 큰 폭으로 감소하였다. 간과 혈청내 중성지방과 콜레스테롤 농도 그리고 간세포내의 지질 과산화물과 간 조직형태의 변형도 돈태반 가수분해물의 농도에 비례해서 감소하였고, 고용량 돈태반군은 silymarin군 만큼 감소하였다. 결과적으로 사염화탄소에 의해서 간 손상을 유발시킨 백서에서 고용량의 돈태반 가수분해물 투여가 간의 손상을 억제하는 효과가 있다고 결론지을 수 있다.

• 한국정밀공학회지
• /
• 제8권3호
• /
• pp.44-54
• /
• 1991

A Study was made on falnk wear in carbide tools in turning SUS304 steel. When an austenitic stainless steel (SUS304 steel) is cut with the tool, saw-toothed chip are produced. It is found that machining SUS304 steel would make a tool worn fast. For increasing productivity, tool wear has to be predicted and controlled. An amended cutting geometry consisting of a negative rake angle ($-6^{\circ}$ ) and a high clearance angle ($-17^{\circ}$ ) is proposed for decreasing carbide tool wear (flank) in the machining of SUS304 steel. The amended cutting geometry is found to make the flank wear lower than a general cutting geometry (rake angle $6^{\circ}$ , clearance angle $5^{\circ}$). The effects of the three cutting variables (cutting speed, feed, tool radius) on the flank wear analyzed by fiting a simple first-order model containing interaction terms to each flank wear parameter by means of regression analysis and the predicted from first-order regression analysis model equation of flank wear.

• 한국정밀공학회지
• /
• 제15권7호
• /
• pp.139-148
• /
• 1998

Internal and external heat sources will cause to deform to machine elements in the contact joint of structure, which results in the change of contact pressure distribution different from initial assembly. Heat induced variations of contact pressure will change the static and dynamic properties such as contact stiffness, damping as well as contact heat conduction in the structure In order to design and control the intelligent machine tool operating in variant conditions more sophisticatedly, the good prediction for the changes of prescribed properties are strongly required especially in the contact elements adjacent to the rotational or linear bearing. This paper presents some computational and experimental results in regard to static and dynamic characteristics of the press-fitted bush and shaft assembly which is a model of the bearing innerrace and shaft assembly. In the condition of heat generation on the outer surface of the bush, the effects of changes in the negative clearance and the heat flux on pressure distribution and dynamic properties are investigated. Results of this study show that the edge effect of the bush and the initial clearance have effects on the transient dynamic characteristics significantly.

• Tuberculosis and Respiratory Diseases
• /
• 제40권4호
• /
• pp.357-366
• /
• 1993

연구배경 : $^{99m}Tc$-DTPA의 폐청소율은 폐포상피세포의 손상도를 반영하고 일부 질환에서는 기존의 폐기능검사보다 더 예민한 것으로 알려져 있다. 흡입된 $^{99m}Tc$-DTPA의 폐청소율은 $^{99m}Tc$-DTPA가 침착되는 부위에 의해 많은 영향을 받아 체외에서 감마카메라로 폐의 방사능 소실속도를 측정하는 방법으로는 섬모운동에 의한 청소속도와 폐포상피를 통한 흡수속도를 구분 할 수 없어 전체 폐의 방사능 소실속도가 폐포상피세포의 투과성만을 반영한다고 할 수 없고 또 장시간동안 감마카메라로 촬영을 해야하는 등 방법이 복잡하다. 흡입된 $^{99m}Tc$-DTPA는 체내에서 24시간 이내에 모두 소변으로 배설되고, 첫 2시간동안 소변으로 배설되는 $^{99m}Tc$-DTPA량은 폐포상피세포를 통한 흡수속도에 의해 결정된다고 알려져 있어, 본 연구자들은 2시간과 24시간 소변내의 방사능배설량의 비를 이용하여 간편하게 폐청소율을 구하는 방법의 유용성 여부를 관찰하기 위해 본 연구를 시행하였다. 방법 : 비흡연 정상인과 미만성 간질성 폐질환환자들을 대상으로 폐기능 검사를 시행하였고 $^{99m}Tc$-DTPA를 vaporizer를 통하여 5분간 흡입후 앙와위에서 폐의 후부상을 감마카메라로 1분단위영상방식으로 30분간 컴퓨터에 수록하여 폐방사능 반감기($T_{1/2}$)를 구하였으며, 또 흡입후 2시간과 24시간 소변을 모아 2시간대 24시간 소변내 방사능배설량비를 구하여 다음과 같은 결과를 얻었다. 결과: 1) 비흡연 정상인에서 $T_{1/2}$와 2시간대 24시간 소변내 방사능배설량비간에는 통계적으로 의미있는 역상관관계가 관찰되었다(r=-0.77, p<0.05). 미만성 폐질환 환자에서 폐방사능 반감기와 2시간대 24시간 소변내 방사능배설량비간에도 역시 의미있는 역상관관계가 관찰되었다 (r=-0.63, p<0.05). 2) 미만성 간질성 폐질환 환자에서 $T_{1/2}$는 $38.65{\pm}11.63$분으로 비흡연 정상인의 $55.53{\pm}11.15$분에 비하여 통계적으로 유의하게 짧았으며, 2시간대 24시간 소변내 방사능배설량비 역시 미만성 간질성 폐질환 환자에서 $52.15{\pm}10.07%$로 비흡연 정상인의 $40.43{\pm}5.53%$에 비해 유의하게 증가되어 있었다(p<0.05). 3) $T_{1/2}$나 2시간대 24시간 소변내 방사능배설량비는 환자군에서 폐확산능과 유의한 상관관계가 없었다(p>0.05). 결론 : 이상의 결과로 $^{99m}Tc$-DTPA의 2시간대 24시간 소변내 방사능배설량비는 폐포상피세포의 투과성을 잘 반영하여 폐포상피세포의 손상정도를 반영하는 간편한 bedside 검사로 생각되며 특히, 폐포상피세포 투과성이 증가되어 있는 미만성 간질성 폐질환 환자에서 예민한 추적경사로 폐확산능과 상호보완적으호 유용하게 사용될 수 있을 것으로 생각된다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권13호
• /
• pp.5515-5519
• /
• 2015

The single nucleotide polymorphism (SNP) ss469415590 in the interferon lambda-4 (IFNL4) gene has recently been reported to have an association with treatment response in chronic hepatitis C. However, any importance of the SNP in association with response to pegylated interferon (PEG-IFN) therapy in patients with chronic hepatitis B (CHB) is unclear. We retrospectively analyzed data for Thai patients with CHB treated with PEG-IFN for 48 weeks. Virological response (VR) for HBeAg-positive CHB was defined as HBeAg seroconversion plus HBV DNA level <2,000 IU/mL at 24 weeks post-treatment. VR for HBeAg-negative CHB was defined as an HBV DNA level <2,000 IU/mL at 48 weeks. The SNP was identified by real time PCR using the TaqMan genotyping assay with MGB probes. A total 254 patients (107 HBeAg-positive and 147 HBeAg-negative) were enrolled in the study. The distribution of TT/TT, ${\Delta}G/TT$ and ${\Delta}G/{\Delta}G$ genotypes was 221 (87.0%), 32 (12.6%) and 1 (0.4%), respectively. Patients with non-TT/TT genotypes had significantly higher baseline HBV DNA levels than patients with the TT/TT genotype. In HBeAg-positive CHB, 41.2% of patients with TT/TT genotype versus 50.0% with non-TT/TT genotype achieved VR (P=0.593). In HBeAg-negative CHB, the corresponding figures were 40.3% and 43.5%, respectively (P=0.777). There was no significant correlation between the SNP genotypes and HBsAg clearance in both groups of patients. In summary, ss469415590 genotypes were not associated with response to PEG-IFN in Thai patients with HBeAg-positive and HBeAg-negative CHB.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1995년도 하계학술대회 논문집 C
• /
• pp.1326-1329
• /
• 1995

An influences of gap clearance, pressure and applied voltage shape on breakdown characteristics are investigated by using a rod-to-plane electrode in $SF_6$ gas. In case of D.C and A.C, a corona stabilization effect increases the breakdown voltage remarkably for lower pressure than 0.2MPa, whereas incase of negative D.C this effect exists independently of gas pressure. This suggests that an insulation optimization in a pratical apparatus is needed to prevent a corona appearance through the removal of local field enhancement.