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201.
Shugang Li Mengchuan Xu Qiang Niu Shangzhi Xu Yusong Ding Yizhong Yan Shuxia Guo Feng Li 《PloS one》2015,10(10)
Aims
In this study, the efficacy of proanthocyanidins (PCs) against oxidative damage was systematically reviewed to facilitate their use in various applications.Methods
A meta-analysis was performed by two researchers. Each investigator independently searched electronic databases, including Cochrane, PubMed, Springer, Web of Science, China National Knowledge Infrastructure (CKNI), China Science and Technology Journal Database (CSTJ), and WanFang Data, and analyzed published data from 29 studies on the effects of PCs against oxidative damage. Oxidative stress indexes included superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), and total antioxidative capacity (T-AOC).Results
Compared with the oxidative damage model group, PCs effectively improved the T-AOC, SOD, GSH, GPx, and CAT levels, and reduced the MDA levels; these differences were statistically significant (P < 0.05). In studies that used the gavage method, SOD (95% CI, 2.33–4.00) and GPx (95% CI, 2.10–4.05) were 3.16-fold and 3.08-fold higher in the PC group than in the control group, respectively. In studies that used the feeding method, SOD (95% CI, 0.32–1.74) and GPx (95% CI, -0.31 to 1.65) were 1.03-fold and 0.67-fold higher in the PC group than in the control group, respectively. Statistically significant differences in the effects of PCs (P < 0.00001) were observed between these two methods. MDA estimated from tissue samples (95% CI, -5.82 to -2.60) was 4.32-fold lower in the PC group than in the control group. In contrast, MDA estimated using serum samples (95% CI, -4.07 to -2.06) was 3.06-fold lower in the PC group than in the control group. The effect of PCs on MDA was significantly greater in tissue samples than in serum samples (P = 0.02).Conclusion
PCs effectively antagonize oxidative damage and enhance antioxidant capacity. The antagonistic effect may be related to intervention time, intervention method, and the source from which the indexes are estimated. 相似文献202.
Yaqiang Zhu Yuhong Liu Lianhong Zhang Yanhui Wang Wendong Niu Cheng Huang 《仿生工程学报(英文版)》2022,(1):1-15
An underwater glider with bionic wings controlled by two operating modes is proposed to perform a variety of marine explo-ration tasks.The system composition of... 相似文献
203.
204.
Hui-Ran Niu Xiang-Dong ZiXiao Xiao Xian-Rong XiongJin-Cheng Zhong Jian LiLi Wang Yong Wang 《Cryobiology》2014
In the present study, we examined the ability of immature germinal vesicle (GV) and subjected to in vitro matured (MII) yak oocytes to survive after cryopreservation as well as their subsequent development following in vitro maturation and fertilization. Both GV and MII oocytes were cryopreserved by using two different vitrification solutions (VS); VS-I contained 10% ethylene glycol (EG) and 10% dimethylsulfoxide (DMSO) in TCM-199 + 20% (v/v) fetal calf serum (FCS) whereas VS-II contained 40% EG + 18% Ficoll + 0.5 M sucrose in TCM-199 + 20% FCS. The percentage of oocytes found to be morphologically normal was greater (P < 0.01) in VS-I group than in VS-II group. Rates of cleavage (30.6–42.2%) and blastocyst formation (2.9–8.9%) did not differ among groups, but were lower than in unfrozen control (55.7% and 25.4%, P < 0.01). These results show that a combination of EG and DMSO or EG, Ficoll and sucrose can be used to cryopreserve yak oocytes in French straws. 相似文献
205.
206.
Shenghe Huang Ruijie Liu Yiding Niu Agula Hasi 《Russian Journal of Plant Physiology》2010,57(4):568-573
207.
Yi-Peng Xu Zheng-Pei Ye Chang-Ying Niu Yan-Yuan Bao Wen-Bing Wang Wei-De Shen Chuan-Xi Zhang 《Journal of microbiology (Seoul, Korea)》2010,48(1):102-110
The Bombyx mandarina nucleopolyhedrovirus (BomaNPV) S1 strain can infect the silkworm, Bombyx mori, but is significantly less virulent than B. mori nucleopolyhedrovirus (BmNPV) T3 strain. The complete nucleotide sequence of the S1 strain of BomaNPV was determined and compared
with the BmNPV T3 strain. The circular, double stranded DNA genome of the S1 strain was 126,770 nucleotides long (GenBank
accession no. FJ882854), with a G+C content of 40.23%. The genome contained 133 potential ORFs. Most of the putative proteins
were more than 96% identical to homologs in the BmNPV T3 strain, except for bro-a, lef-12, bro-c, and bro-d. Compared with the BmNPV T3 strain, however, this genome did not encode the bro-b and bro-e genes. In addition, hr1 lacked two repeat units, while hr2L, hr2R, hr3, hr4L, hr4R, and hr5 were similar to the corresponding
hrs in the T3 strain. The sequence strongly suggested that BomaNPV and BmNPV are variants with each other, and supported the
idea that baculovirus strain heterogeneity may often be caused by variation in the hrs and bro genes. 相似文献
208.
This study was conducted to examine the effects of clipping and nutrient addition on plant traits of a dominant perennial forb species, Heteropappus altaicus (Willd.) Novopokr. (Compositae), at both the individual and population levels in a temperate steppe in northern China. A nested experimental design was used with clipping as the main factor and nutrient, including nitrogen (N), phosphorus (P) and both, addition as the second factor. The main effect of clipping reduced plant height, aboveground biomass (AGB) per plant, and pollen production per floret by 15.8, 34.3, 28.0% (all p < 0.05), respectively, but enhanced reproductive allocation and population density by 8 and 28.2% (both p < 0.05), respectively, suggesting contrary effects of clipping on H. altaicus traits at the individual and population levels. N addition significantly stimulated plant height, AGB per plant, reproductive allocation, pollen diameter, and pistil length, but decreased population density. The main effects of P addition also stimulated the plant traits at individual level, but did not change population traits. The significant interactions of clipping and nitrogen addition were observed on AGB per plant, pollen production, and population density. The differential responses of H. altaicus at the individual and population levels to clipping and nutrient addition indicate that the future dynamics of H. altaicus in the temperate steppe are uncertain and need long-term research to demonstrate. 相似文献
209.
Girijavallabhan VM Chen L Dai C Feltz RJ Firmansjah L Li D Kim SH Kozlowski JA Lavey BJ Kosinski A Piwinski JJ Popovici-Muller J Rizvi R Rosner KE Shankar BB Shih NY Siddiqui MA Tong L Wong MK Yang DY Yang L Yu W Zhou G Guo Z Orth P Madison V Bian H Lundell D Niu X Shah H Sun J Umland S 《Bioorganic & medicinal chemistry letters》2010,20(24):7283-7287
Our research on hydantoin based TNF-α converting enzyme (TACE) inhibitors has led to an acetylene containing series that demonstrates sub-nanomolar potency (K(i)) as well as excellent activity in human whole blood. These studies led to the discovery of highly potent TACE inhibitors with good DMPK profiles. 相似文献
210.
Peng He Yan Niu Zhen-hua Mei Jun-fang Bao Xue-mei Sun 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(15-16):1093-1097
In this paper, the amount of ascorbic acid (AA) in single rat peritoneal mast cell was determined by the method of capillary electrophoresis (CE) with electrochemical detection (ED) at a carbon fiber microdisk bundle electrode. The CE–ED system and the single-cell injection system were rearranged to make the operation more convenient and efficient. In the experiment, a self-made holder made of foam was used to keep the capillary from swing, which kept the stability of the baseline of the electropherogram. The single cell was lysed completely within 5 s using the 0.1% sodium dodecylsulfate (SDS) as the cell lysis solution together with the lysis voltage of 2 kV. The quantitation analysis was accomplished by the use of calibration curves, and the amount of AA in single rat peritoneal mast cell was from 2.4 to 7.1 fmol. 相似文献