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11.
Effective extraction of elastase from Bacillus sp. fermentation broth using aqueous two-phase system 总被引:1,自引:0,他引:1
INTRODUCTION Aqueous two-phase system (ATPS) is widely used in biochemistry and biotechnology for purifica- tion of proteins (Diamond and Hsu, 1992; Balasubramaniam et al., 2003), enzymes (Pan et al., 2001; Bim and Franco, 2000), amino acids (Li et al., 2002), antibiotics (Yang et al., 1994; Guan et al., 1994), nucleic acids (Ohlsson et al., 1978; Kimura, 2000), aroma compounds (Marco et al., 2000) and lactic acid (Planas et al., 1998). ATPS is mainly composed of two-incompatible p… 相似文献
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DETERMINATIONOFCYCLOTRIME-THYLENETRINITRAMINEINSERUMOFRABBITBYRP-HPLCChenYong;YuanZhuo-bin(GraduateSchool,AcademiaSinica.Beij... 相似文献
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Claudia Li 《中学生百科》2007,(11)
XX/XX/XX, Primary election of Changsha Section...XX/XX/XX, Primary election of Hangzhou Section...XX/XX/XX, Semi-finalsXX/XX/XX, FinalsYou must be very familiar with the schedule above, if only, you spend some time in front of computers or TV sets. Yes, this is the schedule of a singing competition known as"Chao Nu"-"Super Voice Girls". Attention please, not"Super Girls"here. 相似文献
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The objectives of this study were to assess the potential of two photosynthetic bacteria (PSB), Rhodopseudomonas palustris HZ0301 and Rhodobacter sphaeroides HZ0302, as probiotics in aquaculture. The viability of HZ0301 and HZ0302 in simulated gastric transit conditions (pH 2.0, pH 3.0 and pH 4.0 gastric juices) and in simulated small intestinal transit conditions (pH 8.0, with or without 0.3% bile salts) was tested. The effects of HZ0301 and HZ0302 on the viability and permeability of intestinal epithelial cell in primary culture of tilapias, Oreochrornis nilotica, were also detected. All the treatments were deter- mined with three replicates. The simulated gastric transit tolerance of HZ0301 and HZ0302 strains was pH-dependent and correspondingly showed lower viability at pH 2.0 after 180 min compared with pH 3.0 and pH 4.0. Both HZ0301 and HZ0302 were tolerant to simulated small intestine transit with or without bile salts in our research. Moreover, there was no significant difference (P〉0.05) among three treatments including the control and the groups treated with HZ0301 or HZ0302 both in intestinal epithelial cell viability and membrane permeability, showing no cell damage. In summary, this study demonstrated that HZ0301 and HZ0302 had high capacity of upper gastrointestinal transit tolerance and were relatively safe for intestinal epithelial cells of tilapias. 相似文献
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Cell therapy in congestive heart failure 总被引:5,自引:0,他引:5
Congestive heart failure (CHF) has emerged as a major worldwide epidemic and its main causes seem to be the aging of the population and the survival of patients with post-myocardial infarction. Cardiomyocyte dropout (necrosis and apoptosis) plays a critical role in the progress of CHF; thus treatment of CHF by exogenous cell implantation will be a promising medical approach. In the acute phase of cardiac damage cardiac stem cells (CSCs) within the heart divide symmetrically and/or asymmetrically in response to the change of heart homeostasis, and at the same time homing of bone marrow stem cells (BMCs) to injured area is thought to occur, which not only reconstitutes CSC population to normal levels but also repairs the heart by differentiation into cardiac tissue. So far, basic studies by using potential sources such as BMCs and CSCs to treat animat CHF have shown improved ventricular remodelling and heart function. Recently, however, a few of randomized, double-blind, placebo-controlled clinical trials demonstrated mixed results in heart failure with BMC therapy during acute myocardial infarction. 相似文献
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Li Luqing 《中外文化交流(英文版)》2008,(3):10-13
Qianmen, located on the southern section of the north-south axis line of Beijing, is known as the most traditional shopping street with the richness of street culture in Beijing. It is the pool of many century-old shops and restaurants which have survived and prospered over the sweep of history with their excellence in quality and service. 相似文献
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Xing Yang Zhao-Long Gu Huimin Wang Jing-Jing Xian Sheng Meng Naoto Nagaosa Wen-Hao Zhang Hai-Wen Liu Zi-Heng Ling Kai Fan Zhi-Mo Zhang Le Qin Zhi-Hao Zhang Yan Liang Jian-Xin Li Ying-Shuang Fu 《国家科学评论(英文版)》2023,(3):127-133
Correlated states have emerged in low-dimensional systems owing to enhanced Coulomb interactions.Elucidating these states requires atomic-scale characterization and delicate control capabilities.Herein,spectroscopic imaging-scanning tunneling microscopy was employed to investigate the correlated states residing in 1D electrons of the monolayer and bilayer MoSe2 mirror twin boundary(MTB).The Coulomb energies,determined by the wire length,drive the MTB into two types of ground states with distinct... 相似文献
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Yanan Wang Yue Liu Na Lyu Zhiyuan Li Sufang Ma Demin Cao Yuanlong Pan Yongfei Hu Hua Huang George F.Gao Xuebin Xu the Bacterium-learning Union Baoli Zhu 《国家科学评论(英文版)》2023,(3):60-76
Salmonella enterica is one of the most common bacterial pathogens in humans and animals.Systematic studies on the trends and geographical distribution of antimicrobial-resistant Salmonella and dominant serovars have been well studied in European and American countries while not in China.Here,taking the One-Health strategy,we used>35 000 Salmonella enterica isolates to explore the temporal and spatial dynamics of dominant serovars in China.We found that Salmonella Typhimurium was the dominant ... 相似文献