http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Cheng Lan Xie (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Cheng Lan Xie,Yin Bing Pan,Liu Qing Hu,Yan Ning Qian 대한마취통증의학회 2015 Korean Journal of Anesthesiology Vol.68 No.5
Background: Propofol has been reported to protect vascular endothelial cells against oxidative stress. In this study we investigated its effect on hydrogen peroxide (H2O2)-induced apoptosis of human umbilical vein endothelial cells (HUVECs) and examined the possible signaling pathways. Methods: HUVECs were pretreated with propofol (1, 5, 25, and 50 μM) for 30 min and then co-incubated with 0.4 mM H2O2 for 4 h. Cell viability was assessed using a Cell Counting Kit-8. Cell apoptosis was analyzed using flow cytometry with annexin V/propidium iodide staining, and evaluated by quantifying caspase-3, Bax, and Bcl-2 expression levels. The expression levels of p38 mitogen activated protein kinase (MAPK), phosphorylated (p)-p38 MAPK, cJun-N-terminal kinases (JNK), phosphorylated (p)-JNK, Akt and phosphorylated Akt [(p)-Akt] (Ser473) were measured by western blotting. Results: H2O2 treatment induced the activation of caspase-3, downregulated Bcl-2 expression, and up-regulated Bax expression, all of which were dose-dependently attenuated by propofol pretreatment. Furthermore, propofol significantly ameliorated H2O2-induced phosphorylation of p38 MAPK, JNK, and Akt in HUVECs. Conclusions: Propofol can protect HUVECs against H2O2-induced apoptosis via a mechanism that may involve p38 MAPK, JNK, and Akt signaling pathways.
-
Zhufan Zou,Xianghao Yang,Hongxiang Xie,Hongyan Lan,Yang Cheng,Jiahui Shen,Youngsoo Bae,Chuanling Si 강원대학교 산림과학연구소 2018 강원대학교 산림과학연구소 학술대회 Vol.2018 No.09
Cellulose nanocrystals (CNCs) are mainly produced by traditional mineral acid hydrolysis, such as sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, etc., which usually causes some problems such as corrosion of equipment, inability of acid recovery, large amounts of water usage, and over-degradation of cellulose. In this work, a green and sustainable approach for the preparation of CNCs was developed by using a mixed acid hydrolysis of oxalic acid and sulfuric acid. The acid ratio, reaction temperature, and reaction time were investigated in detail. It was discovered that a high yield up to 85 % was achieved by this mixed acid with a ratio of 5:1:4 for sulfuric acid: oxalic acid: H2O respectively at 95 oC for 2 h. Results showed that the resultant CNCs have a narrow particle size of 416±35 nm (based on dynamic light scattering). TEM characterization showed the CNCs was perfect whisker morphology. Also, the obtained CNCs exhibited superior dispersion stability in water due to the introduction of carboxyl group on the surface of CNCs by oxalate esterification. Thermogravimetric analyses revealed that the resultant CNCs showed a much higher thermal stability (315 °C) than the traditional sulfuric acid hydrolyzed CNCs. In addition, over 90% of oxalic acid could be recovered by a simple recrystallization step. Thus, the present work demonstrated an efficient and green preparation method of CNCs with high yield and high thermal stability.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
