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1.
利用当前通行的关系数据库技术、采用VB编程语言和ACCESS数据库 ,设计了高分子化学教学试题库系统应用软件———“试卷魔术师”。它由四个模块组成 ,即试题库模块、试卷分析模块、资料库模块和辅助模块。具有试题的录入、删除、修改和访查、手工或自动生成试卷、试卷分析以及资料查阅等诸多功能。满足授权的用户可以利用它随机抽卷、查阅相关资料及历史成绩等。它不仅可以作为高分子化学课程教师生成试卷、分析试卷的有力工具 ,又可作为本专业学生进行高分子化学试题训练、自学并阅读课外参考资料的有效手段。它使用方便 ,操作简单 ,针对性强 ,是一种较为实用的计算机辅助教学软件工具  相似文献   

2.
中药材全息指纹谱图库的建立   总被引:20,自引:0,他引:20  
王龙星  肖红斌  梁鑫淼 《色谱》2002,20(1):78-80
 设计并建立了中药材全息指纹谱图库软件 ,用于存放各种指纹谱及其相关信息。该数据库将为中药分析及其质量控制提供帮助与参考。  相似文献   

3.
NAPRALERT: computer handling of natural product research data   总被引:1,自引:0,他引:1  
Research in natural products, not unlike many other fields of investigation, requires access to large amounts of prior experimental data relevant to specific projects. The most efficient method of identifying and analyzing these data currently employs computer handling of the information. The NAPRALERT database has been designed to meet this need relevant to the development of natural products. It has also been designed, through analysis of existing literature and its contained data, to provide a means to predictively identify taxonomic sources most promising from specific biological activities.  相似文献   

4.
As high-resolution biological transmission electron microscopy (TEM) has increased in popularity over recent years, the volume of data and number of projects underway has risen dramatically. A robust tool for effective data management is essential to efficiently process large data sets and extract maximum information from the available data. We present the Electron Microscopy Electronic Notebook (EMEN), a portable, object-oriented, web-based tool for TEM data archival and project management. EMEN has several unique features. First, the database is logically organized and annotated so multiple collaborators at different geographical locations can easily access and interpret the data without assistance. Second, the database was designed to provide flexibility to the user, so it can be used much as a lab notebook would be, while maintaining a structure suitable for data mining and direct interaction with data-processing software. Finally, as an object-oriented database, the database structure is dynamic and can be easily extended to incorporate information not defined in the original database specification.  相似文献   

5.
The TOPological Substructural MOlecular DEsign (TOPS-MODE) approach has been used to predict the anti-HIV activity in MT-4 assays (Estrada et al., 2002) of a diverse range of purine-based nucleosides. A database of 206 nucleosides has been selected from the literature and a theoretical virtual screening model has been developed. The model is able of discriminating between compounds that have anti-HIV activity and those that do not, with a good classification level of 85% in the training and 82.8% in the cross-validation series. On the basis of the information generated by the model, the correct classification of practically 80% of compounds from an external prediction set has been achieved using the theoretical model. Furthermore, the contribution of a range of molecular fragments to the pharmacological action has been calculated and this could provide a powerful tool in the design of nucleoside analogues that show activity against the HIV. Finally, a QSAR model has been developed that allows quantitative data to be obtained regarding the pharmacological potency shown by this type of compound.  相似文献   

6.
COMAR is the international database for certified reference materials. A new user-friendly web-based version, COMAR2, has been developed by BAM and CONET Consulting AG which will be available in December 2002. The advantages of COMAR2 are briefly explained.Presented at the International ILAC/IAF Conference on Accreditation in Global Trade, 23-25 September 2002, Berlin, Germany  相似文献   

7.
To support interpretation of observed atmospheric krypton radioisotopes, a database of krypton radioisotope in the primary coolant of CANDU reactors has been established. This database is comprised of 40,000 records of high-quality 89Kr, 87Kr, 88Kr and 85mKr analyses. Records from the database were retrieved by a specifically designed data-mining module and subjected to further analysis. Results from the analysis were subsequently used to study isotopic ratios of observed krypton radioisotopes in the CANDU reactor primary coolant. These studies provided practical information on the characterization of CANDU reactor krypton radioisotope, which can potentially be used to discriminate between reactor effluent and fuel reprocessing for nuclear safeguard 85Kr monitoring applications (Kalinowski et al., J Environ Radioact 73:203, 2004). The study also has some potential application to Fissile material cut-off treaty.  相似文献   

8.
To support interpretation of observed atmospheric 135Xe, 133Xe, 133mXe and 131mXe, a database of xenon radioisotope in the primary coolant of CANDU reactors has been established. This database is comprised of 40000 records of high-quality xenon radioisotope analyses. Records from the database were retrieved by a specifically designed data-mining module and subjected to further analysis. Results from the analysis were subsequently used to study isotopic ratios of observed xenon radioisotopes in the CANDU reactor primary coolant. These studies provided novel and practical information on the characterization of CANDU reactor xenon radioisotope releases, which can be used to discriminate between reactor effluence and underground nuclear test releases.  相似文献   

9.
Point Accepted Mutation (PAM) is the Markov model of amino acid replacements in proteins introduced by Dayhoff and her co-workers (Dayhoff et al., 1978). The PAM matrices and other matrices based on the PAM model have been widely accepted as the standard scoring system of protein sequence similarity in protein sequence alignment tools. Here, we present Contact Accepted mutatiOn (CAO), a Markov model of protein residue contact mutations. The CAO model simulates the interchanging of structurally defined side-chain contacts, and introduces additional structural information into protein sequence alignments. Therefore, similarities between structurally conserved sequences can be detected even without apparent sequence similarity. CAO has been benchmarked on the HOMSTRAD database and a subset of the CATH database, by comparing sequence alignments with reference alignments derived from structural superposition. CAO yields scores that reflect coherently the structural quality of sequence alignments, which has implications particularly for homology modelling and threading techniques.  相似文献   

10.
The inclusion of a Chemical Abstracts Service (CAS) Registry Number index in HEEP has led to the need for a special database designed to link substance names with their appropriate CAS chemical compound Registry Numbers. Begun in 1968 as a tape record with batch mode updates and few record modification capabilities, the information system, which we call CHEMFILE, has evolved to its current form of disk storage with on-line access for file maintenance.  相似文献   

11.
Summary The computer program AMI - Quality Assessment Scheme (AMIQAS) was designed to give easy statistical management of analytical data in relation to method evaluation, internal quality control and proficiency testing. The program is designed in accordance with the recommendation of the ISO 5725 guideline and other official recommendations. The program consists of a database, test for outliers, statistics and graphs for evaluation of an analytical method for chemical, biological and environmental analysis, different control charts to be used in day-to-day internal quality control (Shewhart charts and z-charts). Finally the program has facilities to perform proficiency testing (also called external quality control) and produce the relevant evaluation reports for the documentation of method performance and quality control of results of measurements. The present paper demonstrates the applicability of the AMIQAS program for integrated method evaluation, internal quality control and proficiency testing using the determination of the concentration of lead in human whole blood as the numerical example.  相似文献   

12.
Structure-based virtual screening (SBVS) utilizing docking algorithms has become an essential tool in the drug discovery process, and significant progress has been made in successfully applying the technique to a wide range of receptor targets. In silico validation of virtual screening protocols before application to a receptor target using a corporate or commercially available compound collection is key to establishing a successful process. Ultimately, retrieval of a set of active compounds from a database of inactives is required, and the metric of enrichment (E) is habitually used to discern the quality of separation of the two. Numerous reports have addressed the performance of docking algorithms with regard to the quality of binding mode prediction and the issue of postprocessing "hit lists" of docked ligands. However, the impact of ligand database preprocessing has yet to be examined in the context of virtual screening and prioritization of compounds for biological evaluation. We provide an insight into the implications of cheminformatic preprocessing of a validation database of compounds where multiple protonated, tautomeric, stereochemical, and conformational states have been enumerated. Several commonly used methods for the generation of ligand conformations and conformational ensembles are examined, paired with an exhaustive rigid-body algorithm for the docking of different "multimeric" compound representations to the ligand binding site of the human estrogen receptor alpha. Chemgauss, a shapegaussian scoring function with intrinsic chemical knowledge, was combined with PLP as a consensus-scoring scheme to rank output from the docking protocol and enrichment rates calculated for each screen. The overheads of CPU consumption and the effect on relative database size (disk requirement) for each of the protocols employed are considered. Assessment of these parameters indicates that SBVS enrichments are highly dependent on the initial cheminformatic treatment(s) used in database construction. The interplay of SMILES representations, stereochemical information, protonation state enumeration, and ligand conformation ensembles are critical in achieving optimum enrichment rates in such screening.  相似文献   

13.
《Comptes Rendus Chimie》2017,20(5):559-572
A novel density-based model derived by a simple modification of the Jouyban et al. model has been proposed to correlate the solubility of solid drugs in supercritical carbon dioxide. The six-parameter model expresses the solubility only as a function of the solvent density and the equilibrium temperature. This model is in contrast to the Jouyban et al. (J. Superiority. Fluids 24 (2002) 19) model, which gives the solubility as a function of the solvent density and the equilibrium temperature and pressure. The performance of the model has been tested on a database of 100 drugs that account for 2891 experimental data points collected from the literature. The comparison in terms of the mean absolute relative deviation for each solid drug and for the entire database between the proposed model and models that have been suggested to be mostly more accurate demonstrates that the proposed model has the best global correlation performance, exhibiting an overall average absolute relative deviation of 8.13%.  相似文献   

14.
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16.
The gene-protein database of Escherichia coli: edition 4.   总被引:10,自引:0,他引:10  
The gene-protein database of Escherichia coli has as its core an index that links each of the protein spots from a two-dimensional polyacrylamide gel to the gene that encodes the protein. Additional information about each protein and its gene is generated from two-dimensional gel analysis or collated from the literature to form the database. Earlier editions of the database have provided periodic updates of information. The current edition does this, but also introduces a new reference gel image produced by an electrophoresis system recently adopted in this laboratory. The new gel system was chosen because it offers an improved opportunity for other investigations to produce close replicas of the reference gel pattern, thereby allowing easier access to the information of the database and encouraging independent contribution to the database. The new gel format also is larger and hence more compatible with computer assisted image analysis, which has become essential for a project of this magnitude. This edition continues the use of the former reference gel images, but adds a reference image of an equilibrium gel of E. coli strain W3110 produced by the new standardized gel system. At this time, 55% of the protein spots annotated on the previous equilibrium reference gel for this organism have been located on the new reference image, and these identifications are included in the tables of the database.  相似文献   

17.
The gene-protein database of Escherichia coli is both an index relating a gene to its protein product on two-dimensional gels, and a catalog of information about the function, regulation, and genetics of individual proteins obtained from two-dimensional gel analysis or collated from the literature. Edition 5 has 102 new entries--a 15% increase in the number of annotated two-dimensional gel spots. The large increase in this edition was accomplished in part by the use of a new method for expression analysis of ordered segments of the E. coli genome, which has resulted in linking 50 gel spots to their genes (or open reading frames) and another 45 to specific regions of the chromosome awaiting the availability of DNA sequence information. Communication of information from the scientific community resulted in additional identifications and regulatory information. To increase accessibility of the database it has been placed in the repository at the National Center for Biotechnology Information (NCBI) at the National Library of Medicine under the name ECO2DBASE. It will be updated twice yearly. This edition of the gene-protein database is estimated to contain entries for one-sixth of the protein-encoding genes of E. coli.  相似文献   

18.
A comprehensive database of gas chromatographic retention properties of chemical compounds has been developed using multiple literature sources. The National Institute of Standards and Technology (NIST) database of retention data for non-polar and polar stationary phases currently contains 292,924 data records for 42,888 compounds. The database includes data for Kováts indices, linear indices, Lee indices, retention times and retention volumes. The first release of this database for non-polar stationary phases is available with NIST/US Environmental Protection Agency (EPA)/National Institutes of Health (NIH) Mass Spectral Database (June 2005) and through the internet (NIST Chemistry WebBook). The paper describes the database and the process by which it has been compiled. The format of data presentation and the quality control procedures are described. Data sources of gas chromatographic retention data are also discussed.  相似文献   

19.
An ion trap/ion mobility/time-of-flight mass spectrometry technique has been used to measure collision cross sections for 660 peptide ions generated by tryptic digestion of 34 common proteins. Measured cross sections have been compiled into a database that contains peptide molecular weight and sequence information. The database is used to generate average intrinsic contributions to cross section (size parameters) for different amino acid residues by solving systems of equations that relate the unknown contributions of individual residues to the sequences and cross sections of database peptides. Size parameters are combined with information about amino acid composition to calculate cross sections for database peptides. Bona fide cross section predictions (made prior to measurement) for peptides observed in tryptic digests of sperm whale myoglobin and yeast enolase are made. Eight of 10 predicted cross sections are within 2% of the experimental values and all 10 are within 3.2%. The utility of size parameters for cross section prediction is explored and discussed.  相似文献   

20.
烟用香精的分析及质控软件的设计   总被引:1,自引:0,他引:1  
利用气相色谱及气相色谱一质谱法对17种品牌卷烟的62种香精进行了分析,研究了香精特征组分的确定方法。另外,还进一步探讨了香精组分对吸味的影响,建立了香精质量控制方法,设计了烟用香精的质控软件对香精质量进行自动判断,实验结果令人满意。  相似文献   

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