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91.
The hexaploid herbaceous species Primula glaucescens Moretti and Primula spectabilis Tratt. (2n = 6x = 66) are two endemics of the Italian Pre-Alps protected by national and international laws. In order to plan conservation strategies for natural populations and to study the influence of the latest glaciation on them we developed a set of microsatellites markers for the endangered Primula species: ten primer pairs allowed analysis of polymorphic disomic loci in P. glaucescens samples and seven of them also amplified polymorphic disomic markers in P. spectabilis. Kirsten Wolff and Giorgio Binelli contributed equally to the paper  相似文献   
92.
图书馆开展大学生信息素养教育的优势与途径   总被引:3,自引:0,他引:3  
论述了对大学生进行信息素养教育的意义,阐明了图书馆在开展大学生信息素养教育过程中起到的优势作用,提出了利用图书馆进行大学生信息素养教育的6种途径。  相似文献   
93.
高校图书馆中文图书采访的质量控制   总被引:3,自引:0,他引:3  
分析了高校图书馆中文图书采访工作中的制约因素,并从采购制度、人员素质、采访方式、质量分析等方面阐述了控制图书采访质量的措施。  相似文献   
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Prostate cancer is the most common cancer in males worldwide. Mass spectrometry-based targeted proteomics has demonstrated great potential in quantifying proteins from formalin-fixed paraffin-embedded (FFPE) and (fresh) frozen biopsy tissues. Here we provide a comprehensive tissue-specific spectral library for targeted proteomic analysis of prostate tissue samples. Benign and malignant FFPE prostate tissue samples were processed into peptide samples by pressure cycling technology (PCT)-assisted sample preparation, and fractionated with high-pH reversed phase liquid chromatography (RPLC). Based on data-dependent acquisition (DDA) MS analysis using a TripleTOF 6600, we built a library containing 108,533 precursors, 84,198 peptides and 9384 unique proteins (1% FDR). The applicability of the library was demonstrated in prostate specimens.  相似文献   
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A key point of protein stability engineering is to identify specific target residues whose mutations can stabilize the protein structure without negatively affecting the function or activity of the protein. Here, we propose a method called RiSLnet (Rapid i dentification of Smart mutant Library using residue network) to identify such residues by combining network analysis for protein residue interactions, identification of conserved residues, and evaluation of relative solvent accessibility. To validate its performance, the method was applied to four proteins, that is, T4 lysozyme, ribonuclease H, barnase, and cold shock protein B. Our method predicted beneficial mutations in thermal stability with ~62% average accuracy when the thermal stability of the mutants was compared with the ones in the Protherm database. It was further applied to lysine decarboxylase (CadA) to experimentally confirm its accuracy and effectiveness. RiSLnet identified mutations increasing the thermal stability of CadA with the accuracy of ~60% and significantly reduced the number of candidate residues (~99%) for mutation. Finally, combinatorial mutations designed by RiSLnet and in silico saturation mutagenesis yielded a thermally stable triple mutant with the half-life (T 1/2) of 114.9 min at 58°C, which is approximately twofold higher than that of the wild-type.  相似文献   
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The Pseudomonas aeruginosa serralysin (E.C. 3.4.24.40.), which is a zinc-dependent metalloprotease from the metzincin superfamily, has quite a broad specificity, which has not yet been clearly identified. We have studied it with an original approach, using a 49-peptide library of the type Z–AXXA (amide) (X=A, L, V, F, S, R, E). The library was analyzed by LC-MS before and after enzymatic hydrolysis. A great number of hydrolyzed peptides were screened and the preferential hydrolysis was the X–X peptide bond, even if in some cases, A–X and X–A bond could be hydrolyzed. No amino acids with a ionized side chain could be found in the P1′ position. The results obtained suggest that the specificity in the Pn′ position, where an hydrophobic residue was preferentially found, seems more selective that in the Pn position. The P1 position was not very specific, but, on a quantitative point of view, the enzymatic activity was particularly increased when R, F or A were in this position. The results allow us to define the P1′ and P1 residues for an optimal substrate of pseudomonal serralysin and usable for the design and the synthesis of a specific inhibitor.  相似文献   
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