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991.
Driven by advancements in high-throughput biological technologies and the growing number of sequenced genomes, the construction of in silico models at the genome scale has provided powerful tools to investigate a vast array of biological systems and applications. Here, we review comprehensively the uses of such models in industrial and medical biotechnology, including biofuel generation, food production, and drug development. While the use of in silico models is still in its early stages for delivering to industry, significant initial successes have been achieved. For the cases presented here, genome-scale models predict engineering strategies to enhance properties of interest in an organism or to inhibit harmful mechanisms of pathogens. Going forward, genome-scale in silico models promise to extend their application and analysis scope to become a transformative tool in biotechnology.  相似文献   
992.
A simple, sensitive and rapid flow injection analysis (FIA) method with resonance light scattering (RLS) was described for the determination of propafenone (PPF). The method was based on the ion‐association reaction of 12‐tungstophosphoric acid (TP) with propafenone. In pH 1.0 acidic medium, TP reacted with PPF to form an ion‐associate complex, which resulted in a significant enhancement of RLS intensity. The maximum scattering peak was located at 340 nm, the RLS intensity was proportional to the concentration of PPF in the range 0.003–9.0 µg/mL, and the detection limit (3σ) of 1.0 ng/mL was obtained at a sampling rate of 60 samples/h. The feasible reaction conditions and FIA parameters for the system were optimized. The method proposed in this paper shows satisfactory reproducibility with a relative standard deviation (RSD) of 2.1% for 10 successive determinations of 2.0 µg/mL PPF. The present method had been successfully applied to the determination of PPF in serum samples and pharmaceutical samples. The results obtained were in agreement with the method used in the Chinese Pharmacopoeia. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
993.
根据小麦基因表达芯片结果,以山融3号小麦叶片为试验材料,克隆获得在盐胁迫处理24 h时表达显著提高的基因TaUES(up-regulated expression under saline-stress in wheat,ID:KC408382)。序列分析显示,TaUES编码一个富含半胱氨酸的97个氨基酸的多肽,该多肽含有1个BowB结构域和10个保守的半胱氨酸残基;与小麦或其他物种BBI型蛋白酶抑制剂氨基酸序列具有较高的同源性。推测TaUES是小麦中一种新的BBI型蛋白酶抑制剂基因。基因表达分析表明,TaUES基因参与盐和干旱胁迫应答。异源过表达转基因功能初步分析表明,过表达TaUES转基因烟草后代株系耐盐性提高。  相似文献   
994.
The stability of brain networks with randomly connected excitatory and inhibitory neural populations is investigated using a simplified physiological model of brain electrical activity. Neural populations are randomly assigned to be excitatory or inhibitory and the stability of a brain network is determined by the spectrum of the network’s matrix of connection strengths. The probability that a network is stable is determined from its spectral density which is numerically determined and is approximated by a spectral distribution recently derived by Rajan and Abbott. The probability that a brain network is stable is maximum when the total connection strength into a population is approximately zero and is shown to depend on the arrangement of the excitatory and inhibitory connections and the parameters of the network. The maximum excitatory and inhibitory input into a structure allowed by stability occurs when the net input equals zero and, in contrast to networks with randomly distributed excitatory and inhibitory connections, substantially increases as the number of connections increases. Networks with the largest excitatory and inhibitory input allowed by stability have multiple marginally stable modes, are highly responsive and adaptable to external stimuli, have the same total input into each structure with minimal variance in the excitatory and inhibitory connection strengths, and have a wide range of flexible, adaptable, and complex behavior.  相似文献   
995.
The title compound, methyl 2-methoxy-7-(4-methylbenzoyl)-4-oxo-6-p-tolyl-4H-furo[3,2-c]pyran-3-carboxylate (C25H20O7), was prepared and characterized by IR and single-crystal X-ray diffraction (XRD). The compound crystallizes in the triclinic space group P ?1 with a?=?8.9554(9) Å, b?=?10.0018(10) Å, c?=?12.7454(13) Å, α?=?67.678(7)°, β?=?89.359(8)° and γ?=?88.961(8)°. In addition to the molecular geometry from X-ray experiment, the molecular geometry and vibrational frequencies of the title compound in the ground state have been calculated using semiempirical AM1 and PM3 methods, as well as Hartree-Fock (HF) and density functional (B3LYP) levels of theory with 6–31G(d) basis set. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from ?180° to +180° in steps of 10°. Besides, frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compound were performed by the B3LYP/6–31G(d) method.  相似文献   
996.
苦豆子根瘤内生细菌分离及表型多样性分析   总被引:1,自引:0,他引:1  
对分离自新疆苦豆子(Sophora alopecuroides)根瘤的60株内生细菌进行了108项表型性状的测定,包括唯一碳源利用、唯一氮源利用、对抗生素和染料的抗性、耐盐性、初始pH值生长、生长温度范围及石蕊牛奶反应、氧化酶、过氧化氢酶和脲酶等.结果表明:新疆苦豆子根瘤内生细菌具有较强的抗逆性,具有较强的耐受高温和耐盐、碱能力.77%的菌株能在50℃条件下生长,43%的菌株能耐受6.0%的NaCl,73%的菌株能在pH为10的碱性环境下生长.聚类分析结果表明在Watson距离为0.26时可聚为11个表观群,代表菌株分别属于芽孢杆菌属(Bacillus sp.)和气芽孢杆菌属(Aerobacillus sp.).  相似文献   
997.
The three major curcuminoids, curcumin, demethoxycurcumin and bis-demethoxycurcumin, from Curcuma domestica Val. (Curcuma longa L.) and Curcuma xanthorrhiza Roxb. (Zingiberaceae) were fully separated and quantified in less than 5 min using a capillary zone electrophoresis method with standard fused-silica capillaries and photodiode array detection. An electrolyte solution of 20 mM phosphate, 50 mM sodium hydroxide and 14 mM beta-cyclodextrin was found to be appropriate. Quantification was performed with 3,4-dimethoxy-trans-cinnamic acid as internal standard, and the limit of detection was 0.01 mg/mL. Extraction, stabilisation during sample storage and quantification procedures were optimised and carried out with drugs and commercial curry powder from different provenances. The results were compared with the photometric method of the monograph Curcumae xanthorrhizae rhizoma of the European Pharmacopoeia.  相似文献   
998.
The fat dormouse (Glis glis) is a traditional game species in the Republic of Croatia. Although today the fat dormouse is not frequently caught as game, it is still a source of animal protein in human nutrition in certain rural areas of Croatia. In this paper the chemical analysis of fat dormouse meat is presented. The average values for the quantity of water, fat, protein and ash in dormouse meat are comparable with the chemical composition of the meat of rabbits and brown hares, except for the important fact that rabbit and hare meat contains a greater quantity of fat on average. According to our results, the meat of fat dormice can be categorised as dietary food, characterised by a small percentage of fat (mean 2.83%) and a high amount of protein (mean 21.01%).  相似文献   
999.
运用随机扩增多态DNA(RAPD)技术,对天目木兰(Magnolia amoena)居群的遗传多样性进行了研究.从40个10-mer随机引物中筛选出14个能得到清晰、稳定扩增带的引物进行扩增,14个引物共检测了94个位点,其中多态性位点为23,占24.4%,计算了12个居群之间的遗传相似度和遗传距离,并运用UPGMA法进行了聚类分析,结果显示相同严地个体间(居群内)的遗传距离较小,遗传多样性水平很低;不同产地个体间(居群间)遗传距离较大,遗传多样性水平较前者高,即天目木兰个体间遗传多样性水平与它的地理分布有关,天目木兰总体较低的遗传多样性是导致它濒危的原因之一。  相似文献   
1000.
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