Information sources tertiary

The literature of chemistry and associated fields has iacreased enormously siace 1980. Kstahlishment of subspecialties and newly defined disciplines as well as iacreased research output have led to an explosion of journals, books, and on-line databases, all of which attempt to capture, record, and disseminate this plethora of knowledge (1). Tertiary reference tools ia chemistry and technology (eg, KJrk-Othmer, 4th ed.) help track the primary Hterature. Excellent references that discuss basic chemical information tools are The Titerature Matrix of Chemistry (1), Chemical Information Sources (2), and Mow to Find Chemical Information (3). 

Once a valuable, key information source has been found—whether it is a tertiary source or a research report—a quick perusal of the references that this source used may yield further valuable citations. If your search has already uncovered the same references as this key source, your search methods gain confidence. 

The Chemical Information Sources Wiki (http //cheminfo. informatics.indiana.edu/cicc/cis/index.php/Main Page) is a guide to the many sources of reference materials available for those with questions related to chemistry. The site includes information on primary, secondary, and tertiary pubheation sources, chemical information databases, physical property information, chemical patent searching, and molecular visualization tools and sites. The material is based on an undergraduate course offered for many years in the Indiana University Department of Chemistry by Gary Wiggins. 

Monographs, reference books, and encyclopedias, e.g., Ullmann s Encyclopedia of Industrial Chemistry, the Kirk-Othmer Encyclopedia of Chemical Technology, or the Encyclopedia of Computational Chemistry are included in this type of literature, which is furthest from the primary literature as concerns time and content. In most cases, tertiary literature summarizes a topic with information from different sources, and additionally evaluates the contents. 

Nuclear magnetic resonance (nmr) spectroscopy is useful for determining quaternary stmcture. The N-nmr can distinguish between quaternary ammonium compounds and amines, whether primary, secondary, or tertiary, as well as provide information about the molecular stmcture around the nitrogen atom. The C-nmr can distinguish among oleic, tallow, and hydrogenated tallow sources (194). 

Tertiary publications, as described by Sewell [52] in Guide to Drug Information, are those publications that are the furthest removed from the literature of original research. The tertiary literature is a distillation and evaluation of data and information first presented in such primary literature sources as research reports, meeting presentations, and journal articles. Being furthest removed from the primary report, the tertiary literature characteristically is the least current and the most vulnerable to misinterpretations, biases, and inaccuracies. But just as characteristic, the tertiary literature is the most accessible, easiest to use, and perhaps the most used of all information resources. Information searches generally start with a perusal of... 

There are different classes of protein sequence databases. Primary and secondary databases are used to address different aspects of sequence analysis. Composite databases amalgamate a variety of different primary sources to facilitate sequence searching efficiently. The primary structure (amino acid sequence) of a protein is stored in primary databases as linear alphabets that represent the constituent residues. The secondary structure of a protein corresponding to region of local regularity (e.g., a-helices, /1-strands, and turns), which in sequence alignments are often apparent as conserved motifs, is stored in secondary databases as patterns. The tertiary structure of a protein derived from the packing of its secondary structural elements which may form folds and domains is stored in structure databases as sets of atomic coordinates. Some of the most important protein sequence databases are PIR (Protein Information Resource), SWISS-PROT (at EBI and ExPASy), MIPS (Munich Information Center for Protein Sequences), JIPID (Japanese International Protein Sequence Database), and TrEMBL (at EBI). ... 

The crystal structures of the E. coli DHFR-methotrexate binary complex (Bolin et al., 1982), of the Lactobacillus casei (DHFR-NADPH-methotrexate ternary complex (Filman et al., 1982), of the human DHFR-folate binary complex (Oefner et al., 1988), and of the mouse (DHFR-NADPH-trimethoprim tertiary complex (Stammers et al., 1987) have been resolved at a resolution of 2 A or better. The crystal structures of the mouse DHFR-NADPH-methotrexate (Stammers et al., 1987) and the avian DHFR—phenyltriazine (Volz et al., 1982) complexes were determined at resolutions of 2.5 and 2.9 A, respectively. Recently, the crystal structure of the E. coli DHFR—NADP + binary and DHFR-NADP+-folate tertiary complexes were resolved at resolutions of 2.4 and 2.5 A, respectively (Bystroff et al., 1990). DHFR is therefore the first dehydrogenase system for which so many structures of different complexes have been resolved. Despite less than 30% homology between the amino acid sequences of the E. coli and the L. casei enzymes, the two backbone structures are similar. When the coordinates of 142 a-carbon atoms (out of 159) of E. coli DHFR are matched to equivalent carbons of the L. casei enzyme, the root-mean-square deviation is only 1.07 A (Bolin et al., 1982). Not only are the three-dimensional structures of DHFRs from different sources similar, but, as we shall see later, the overall kinetic schemes for E. coli (Fierke et al., 1987), L. casei (Andrews et al., 1989), and mouse (Thillet et al., 1990) DHFRs have been determined and are also similar. That the structural properties of DHFRs from different sources are very similar, in spite of the considerable differences in their sequences, suggests that in the absence, so far, of structural information for ADHFR it is possible to assume, at least as a first approximation, that the a-carbon chain of the halophilic enzyme will not deviate considerably from those of the nonhalophilic ones. 

X-ray crystallography and NMR are, of course, the indispensable sources of information about protein tertiary structure at high resolution (Rhodes 1993 McRee 1993 ... 

This information may be gleaned from specialized ADR resources, texts, and other tertiary sources, including the FDA-approved product label. However, this information must often be augmented using additional data from secondary sources. At minimum, this should include searches of the bibliographic databases from the National Library of Medicine (Medline and Toxnet) and Excerpta Medica (Embase). 

The sources of drug information are extremely diverse and include journals, books, conference proceedings, patents, and trade literature. These sources are generally classified as primary, secondary, or reference compendia/tertiary information. Primary refers to original and new information and secondary refers to reviews and commentaries of the primary information, whereas reference compendia or tertiary usually refers to compilations such as dictionaries and pharmacopoeias. When conducting an information literature search, it is wisest to begin with the reference/ tertiary sources as necessary and then move on to the secondary and finally the primary sources of drug information. 

No comparative studies of all anticholinergics in the same animal species or on the same test system are available. The above data were assembled or cross-calculatedfrom information reported in a number of sources therefore the activitiesare relative and approximate. However, the informationisuseful to compare the availableanticholinergicagents. AH quaternary salts are bromides, and dl tertiary amines are listed as hydrochlorides unless otherwise specified. 

Other applications that should be considered for integration involve access to tertiary literature sources directly from the clinical application. The purpose of information is to reduce uncertainty. The ability for the pharmacist to access and validate decisions based on evidence found in the literature is an important skill and a necessary requirement for clinical software support. This kind of support can be provided in palm-top form, from network resources, and as intranet applications. 

As in university or academic-based drug information centers, published literature used to develop an answer to a drug information inquiry can be divided into primary, secondary, and tertiary sources. Primary sources are the most desirable type of data to use and can be subdivided, depending on the type of data collected. Information gleaned from randomized, prospective, double-blind trials result in data more useful than just one case report on a given topic. Ideally, the most rigorous data available are used however, case reports and abstracts may be the only available literature published. Peer-reviewed, well-respected journals should be used. 

Identifies and retrieves the best available information about pharmacotherapy by searching appropriate tertiary, secondary, and primary sources. The pharmacotherapist is adept at using computer technology to collect information. 

However, retrieval services cater for both current-awareness and retrospective search needs. Whilst computerised document retrieval services are useful for current awareness, there has been much activity to apply computer techniques to actual information retrieval, particularly for retrospective searching. This has taken the form of setting up specialised data banks for numeric and structurail information. These are a form of secondary service but are more closely related to handbooks and encyclopaedias than to abstract publications. (Data handbooks, etc., are sometimes referred to as tertiary sources, but since secondary sources are guides to the primary, the term tertiary sources is more accurately applied to guides to the secondary literature s).)... 

With the status of current secondary and tertiary services being as briefly stated above, the innovative approach of the Solubility Data Project is that its compilation and critical evaluation work involve consolidation and reprocessing services when both activities are based on intellectual and scholarly reworking of information from primary sources, it comprises compact compilation, rationalization and simplification, and the fitting of isolated numerical data into a critically evaluated general framework. 

The Solubility Data Project has developed a mechanism which involves a number of innovations in exploiting the literature fully, and which contains new elements of a more imaginative approach for transfer of reliable information from primary to secondary/tertiary sources. The fundamental trend of the Solubility Data Project is toward integration of secondary and tertiary services with the objective of producing in-depth critical analysis and evaluation which are characteristic to secondary services, in a scope as broad as conventional tertiary services. 

Finally, we turn to the relatively prosaic question of sources of information. We would have preferred to recommend only suitably advanced textbooks and articles in review journals and monographs. Somehow these sources appear more permanent than papers in the primary research journals, yet by definition secondary and tertiary sources of information are more dated. Wonders abound in all of them. We admit arbitrariness in our choices— no universal criterion for their inclusion other than the presence of exotic chemistry can be offered. There was too much, rather than too little, to choose among. After all, we were not allowed to write our own volume, The Encyclopedia of Exotica. We close the introduction with two quotes that provided us a guideline. The first is from a psalm that provides implicit chastisement for whatever choice we made the second is from the Mishnah, the legal core of the Talmud, which offers a source of reassurance for our efforts. 

A system containing 20% of a tertiary alcohol in petroleum ether separated all the investigated pigments except -carotene and lycopene. A typical separation is shown in Fig. 12, where an extract from parsley was used as the carotenoid source, and the efficient spread of the polar pigments is evident. The separations are even better on plastic-backed silica gel (0.2 mm, Merck), where extremely narrow bandwidth can be produced. Combined with circular TLC, the system provides valuable information about samples with complicated pigment patterns in the polar area. 

While monographs include books written for professionals, tliey are either primary or secondary sources of knowledge and information. Textbooks are also part of the tertiary literature. They are derived from primary and secondary sources. Textbooks provide extensive explanations and proofs for the material covered to provide the reader with an opportunity to understand a specific subject thoroughly. 

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