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81.
Zong-wen Pang Jing-juan Liang Xiao-juan Qin Ji-rui Wang Jia-xun Feng Ri-bo Huang 《Biotechnology letters》2010,32(12):1847-1851
Kluyveromyces marxianus GX-15 was mutated multiple times by alternately treatment with UV irradiation and NTG for two cycles. Four mutant strains
with improved ethanol yield were obtained. The maximum ethanol concentration, ethanol yield coefficient and theoretical ethanol
yield of the best mutant strain, GX-UN120, was 69 g/l, 0.46 g/g and 91%, respectively, when fermenting 150 g glucose/l at
40°C. The corresponding values for GX-15 were 58 g/l, 0.39 g/g and 76%, respectively. GX-UN120 grew well in 11% (v/v) of ethanol,
while GX-15 could not grow when ethanol was greater than 8% (v/v). 相似文献
82.
目的了解铜绿假单胞菌(PA)在医院内感染的分布特点及其耐药性,指导临床合理用药,降低医院感染率。方法回顾分析2005年1月至2008年11月我院临床分离的铜绿假单胞菌152株,按WHO推荐的NC-CLS标准方法(K—B法)进行药敏试验,分析菌株的临床分布特征及体外药敏结果。结果铜绿假单胞菌在临床上主要以呼吸道感染为主。在17种临床常用抗生素中,多表现为多重耐药。美洛培南、亚胺培南及左旋氧氟沙星抗PA效果最好,耐药率分别只有14.47%、14.47和5.26%。结论多重耐药铜绿假单胞菌在临床广泛存在,应当根据临床体外药敏结果合理选择抗菌药物进行治疗,以取得良好临床效果并减少耐药菌产生;同时规范院内感染控制措施,减少耐药菌株的播散。 相似文献
83.
为研究CSFV强毒感染对猪外周血白细胞的影响,本研究用猪瘟病毒石门株(CSFV SM)感染60日龄仔猪后,分析外周血中CSFV核酸载量动态变化、白细胞亚群变化和白细胞SLAⅠ和SLAⅡDR分子的表达情况。实验结果显示:实验仔猪经CSFV感染后48小时体温升高并可以在血液中检测到CSFV核酸,核酸载量持续升高,在感染后6日(DPI)达到最大值,为2 DPI时核酸载量的104.84±0.98倍;WBC、LYM、PLT数量持续降低,WBC在1DPI和2DPI分别降至65.87%和50.00%,LYM在1~3DPI分别降至70.68%、47.88%和23.29%,PLT数量持续降低,6DPI时仅为初始值的34.59%;NK、γδT、Tc、Th、CD3+CD4+CD8+和CD3-CD4-CD8-淋巴细胞在感染后均不同程度的减少,其中NK细胞在1DPI时减少78.49%,而后变化与1DPI比较差异不显著,γδT、Tc、CD3-CD4-CD8-、CD3+CD4+CD8+在3DPI时分别降至41.74%、43.83%、15.87%和32.96%,Th细胞在感染后持续下降,在6DPI时减少至42.95%;感染后淋巴细胞中表达S... 相似文献
84.
Liu LB Hashi Y Qin YP Zhou HX Lin JM 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,845(1):61-68
An automated online gel permeation chromatography-gas chromatograph mass spectrometer (GPC-GC/MS) was developed for the rapid determination of residual pesticides in agricultural products. Pesticides were extracted from homogenized food samples with acetonitrile and decontaminated via the matrix solid-phase dispersion (MSPD) technique, using a primary secondary amine as sorbent prior to GPC-GC/MS analysis. A slightly modified preparation method and automated GPC step proved useful in minimizing matrix interference. To evaluate the performance of the system, 97 target pesticides were spiked at a concentration of 0.1mg/kg into a range of food types, including potato, cabbage, carrot, apple, orange, cucumber, and rice. A low flow rate of 0.1 mL/min in GPC resulted in a 40-fold reduction in solvent consumption compared with conventional GPC column applications. The combination of MSPD technique and GPC-GC/MS for the analysis of the 97 pesticides can be accomplished within 90 min. Most pesticides were recovered in the range of 70-120%, with relative standard deviation generally less than 10%. The results demonstrate that the method can be successfully applied with acceptable recoveries to a broad range of target pesticides within a diverse range of food types. 相似文献
85.
86.
Angiostatin production in cultivation of recombinant Pichia pastoris fed with mixed carbon sources 总被引:4,自引:0,他引:4
A recombinant strain of Pichia pastoris with a phenotype of MutS was used to produce angiostatin. Due to the low methanol consumption rate of this strain, both methanol and glycerol feedings, that produced oscillation in dissolved O2 concentration, were used during the expression phase to improve cell growth and angiostatin expression. However, enhanced cell growth led to nitrogen limitation that suppressed further production of angiostatin, but addition of ammonia allowed angiostatin concentration to reach 108 mg l–1 after an expression period of 96 h. The ratio of consumed glycerol to methanol of 1.5:1 (w/w) in the expression phase suggested that methanol played an important role in the metabolism of carbon sources. 相似文献
87.
Li H Jin G Qin J Tian M Shi J Yang W Tan X Zhang X Zou L 《Histochemistry and cell biology》2011,136(5):515-526
During the central nervous system (CNS) development, radial glia cells (RGCs) play at least two essential roles, they contribute
to neuronal production and the subsequent guidance of neuronal migration, whereas its precise distribution and contribution
to cerebral cortex remains less understood. In this research, we used Vimentin as an astroglial marker and Sox2 as a neural
progenitor marker to identify and investigate RGCs in rat cerebral cortex at embryonic day (E) 16.5. We found that the Sox2+
progenitor cells localized in the germinal zone (GZ) of E16.5 cerebral cortex, ~95% Sox2+ cells co-localized with Vimentin+
or Nestin+ radial processes which extended to the pial surface across the cortical plate (CP). In vitro, we obtained RG-like
cells from E16.5 cerebral cortex on adherent conditions, these Sox2+ Radial glia (RG)-like cells shared some properties with
RGCs in vivo, and these Sox2+ RG-like cells could differentiate into astrocytes, oligodendrocytes and presented the radial
glia—neuron lineage differentiation ability. Taken together, we identified and investigated some characterizations and properties
of Sox2+ RGCs derived from E16.5 cerebral cortex, we suggested that the embryonic Sox2+ progenitor cells which located in
the cortical GZ were mainly composed of Sox2+ RGCs, and the cortex-derived Sox2+ RG-like cells displayed the radial glia—neuron
lineage differentiation ability as neuronal progenitors in vitro. 相似文献
88.
鄂伦春族体质现状及其与60年前资料的比较 总被引:8,自引:6,他引:8
对内蒙古鄂伦春自治旗191名(男85,女106),鄂伦春族成的人进行了活体观察与测量,总结了鄂伦春的体质和类型并在城乡之间、与60年前同一地区的资料及我国北方一些的体质数据进行了比较。 相似文献
89.
Jin Wang Kai-Jing Zuo Jie Qin Lida Zhang Lan Su Junrong Liu Hua Ling Jing-Ya Zhao You-Fang Cao Ke-Xuan Tang 《Acta Physiologiae Plantarum》2007,29(1):1-9
A novel cDNA clone encoding a COR413-like gene was isolated by suppression subtraction hybridization and cDNA library screening from sea-island cotton (Gossypium barbadense). This gene (designated as GbCOR413, Accession number: AY761065) has a total length of 893 bp with an open reading frame of 600 bp, encoding a predicated polypeptide
of 200 amino acids with a molecular weight of 22.74 kDa and a predicated pI of 9.2. Bioinformatics analyses revealed that this gene belonged to a novel stress-regulated multi-spanning transmembrane
protein family without signal peptide. By means of semi-quantities RT-PCR analysis, the expression of GbCOR413 under short-term cold treatment at 4°C, water submergence and abscic acid treatment was investigated. Our studies suggested
that the cloned gene was a new member of COR gene family which was slowly responsive to cold stress in cotton.
Jin Wang and Kai-Jing Zuo are co-first authors of this paper. 相似文献
90.
Molecular Biology Reports - Chemosensory receptors in the dendritic membrane of olfactory cells are critical for the molecular recognition and discrimination of odorants. Tropidothorax elegans is a... 相似文献