MEDLINEplus: building and maintaining the National Library of Medicine's consumer health Web service.

MEDLINEplus is a Web-based consumer health information resource, made available by the National Library of Medicine (NLM). MEDLINEplus has been designed to provide consumers with a well-organized, selective Web site facilitating access to reliable full-text health information. In addition to full-text resources, MEDLINEplus directs consumers to dictionaries, organizations, directories, libraries, and clearinghouses for answers to health questions. For each health topic, MEDLINEplus includes a preformulated MEDLINE search created by librarians. The site has been designed to match consumer language to medical terminology. NLM has used advances in database and Web technologies to build and maintain MEDLINEplus, allowing health sciences librarians to contribute remotely to the resource. This article describes the development and implementation of MEDLINEplus, its supporting technology, and plans for future development.

Pre-exercise branched-chain amino acid administration increases endurance performance in rats.

This study investigated the effects of pre-exercise branched-chain amino acid (BCAA) administration on blood ammonia levels and on time to exhaustion during treadmill exercise in rats. Adult female Wistar rats were trained on a motor driven treadmill. After a 24-h fast, rats were injected intraperitoneally (i.p.) with 1 mL of placebo or BCAA (30 mg), 5 min before performing 30 min of submaximal exercise (N = 18) or running to exhaustion (N = 12). In both cases, rats were sacrificed immediately following exercise, and blood was collected for the measurement of glucose, nonesterified fatty acid (NEFA), lactic acid, BCAA, ammonia, and free-tryptophan (free-TRP) levels. Control values were obtained from sedentary rats that were subjected to identical treatments and procedures (N = 30). Plasma BCAA levels increased threefold within 5 min after BCAA administration. Mean run time to exhaustion was significantly longer (P < 0.01) after BCAA administration (99 +/- 9 min) compared with placebo (76 +/- 4 min). During exercise, blood ammonia levels were significantly higher (P < 0.01) in the BCAA treated compared with those in the placebo treated rats both in the 30-min exercise bout (113 +/- 25 mumol.L-1 (BCAA) vs 89 +/- 16 mumol.L-1) and following exercise to exhaustion (186 +/- 44 mumol.L-1 (BCAA) vs 123 +/- 19 mumol.L-1). These data demonstrate that BCAA administration in rats results in enhanced endurance performance and an increase in blood ammonia during exercise.

Interlibrary loan in U.S. health sciences libraries: journal article use.

Health sciences libraries in the United States use the National Library of Medicine (NLM) DOCLINE system to request more than two million items annually through interlibrary loan (ILL). Ninety-seven percent of all ILL requests are for journal articles. In this study, NLM analyzed four million ILL requests entered into the DOCLINE system during two twelve-month periods ending September 30, 1992. The requests were analyzed at both the journal title level and article level. Data for the two years were found to be remarkably similar. Results showed that a large number of journals are required to fill ILL requests and that there is a relatively low number of repeat requests for most journal articles. Seventy-six percent of journal articles analyzed were requested only once, and fewer than 1% were requested more than ten times. About 39% of journals used to fill ILL requests were indexed in MEDLINE at some time, while 84% of the articles supplied were indexed in MEDLINE. Ninety-two percent of articles supplied were from English-language journals. Sixty-seven percent of articles were published in the most recent five years, and 85% in the most recent ten years. The 100 most frequently requested articles for each of the two years were examined to determine characteristics such as language, where they were indexed, and the subject matter. This study has provided valuable information for planning of NLM's interlibrary document delivery services and also should have significance for libraries and other organizations involved in document delivery.

Service providers and users discover the Internet.

Although the Internet has evolved over more than twenty years, resources useful to health information professionals have become available on the Internet only recently. A survey conducted by the Regional Medical Libraries of the National Network of Libraries of Medicine in the fall of 1993 indicates that libraries at academic institutions are much more likely to have access to the Internet (72%) than are libraries in hospital environments (24%). Health information professionals who take on the challenge and exploit the Internet's resources find rewards for themselves and their clients. The basic electronic mail capability of the Internet allows colleagues to collaborate, communicate, and participate in daily continuing education. Internet terminal and file-transfer capabilities provide improved access to traditional resources and first-time access to new electronic resources. Through the Internet, online catalogs are available worldwide, and document delivery is faster, cheaper, and more reliable than ever before. Institutions can make organizational, full-text, online, and publication information available through Internet tools such as direct file-transfer protocol (FTP), menu-based Gopher, and hypertext-based Mosaic. The National Library of Medicine (NLM) is among organizations finding new ways to provide service through the Internet. NLM now uses electronic mail to communicate with users, FTP service to distribute publications, and tools such as Gopher and Mosaic to distribute publications and graphics and connect users to online services. The Internet allows service providers and health sciences information professionals to work in a rich, new medium whose potential is just beginning to be explored. At the same time, its characteristics--including lack of formal organization, standards, quality control, and permanence--pose a challenge.

SAIL: automating interlibrary loan.

The National Library of Medicine (NLM) initiated the System for Automated Interlibrary Loan (SAIL) pilot project to study the feasibility of using imaging technology linked to the DOCLINE system to deliver copies of journal articles. During the project, NLM converted a small number of print journal issues to electronic form, linking the captured articles to the MEDLINE citation unique identifier. DOCLINE requests for these journals that could not be filled by network libraries were routed to SAIL. Nearly 23,000 articles from sixty-four journals recently selected for indexing in Index Medicus were scanned to convert them to electronic images. During fiscal year 1992, 4,586 scanned articles were used to fill 10,444 interlibrary loan (ILL) requests, and more than half of these were used only once. Eighty percent of all the articles were not requested at all. The total cost per article delivered was $10.76, substantially more than it costs to process a photocopy request. Because conversion costs were the major component of the total SAIL cost, and most of the articles captured for the project were not requested, this model was not cost-effective. Data on SAIL journal article use was compared with all ILL requests filled by NLM for the same period. Eighty-eight percent of all articles requested from NLM were requested only once. The results of the SAIL project demonstrated that converting journal articles to electronic images and storing them in anticipation of repeated requests would not meet NLM's objective to improve interlibrary loan.

Impact of DOCLINE on interlibrary loan service at the National Library of Medicine.

In March 1985, the National Library of Medicine (NLM) began implementation of DOCLINE, its automated interlibrary loan request routing and referral system. By the end of fiscal year (FY) 1987, over 1,400 biomedical libraries in all seven regions of the Regional Medical Library network were using the system. This report summarizes the findings of an analysis of the interlibrary loan (ILL) requests received in FY 1987, comparing the results with a similar analysis done in FY 1984 to describe any changes in the requests or service which might be attributable to DOCLINE implementation. DOCLINE has had a substantial impact upon ILL loan service at NLM. An increase in the number of ILL requests (35% over FY 1984) can be attributed to the speed and ease with which requests may be routed to NLM through DOCLINE. Requests which cannot be filled by local or regional libraries are automatically routed by the system to NLM as the library of last resort. NLM's fill rate for serial requests has declined, however, from 78% filled in FY 1984 to 67% filled in FY 1987. Some of the decline results from the 11,000 requests that NLM did not fill because the borrowing libraries were not willing to pay the NLM charge for filling the loans.

A comparison of interlibrary loan requests received by the National Library of Medicine: 1959 and 1984.

In 1962, an analysis of interlibrary loan requests for serials filled by NLM in 1959 was published. In the twenty-five years following 1959, important changes occurred in the biomedical library community, which had a significant impact on interlibrary loan activities, including the development of MEDLARS and online searching, the Regional Medical Library (RML) network, and union listing for serials. To describe NLM's current interlibrary loan request traffic for serials and to identify any significant changes in traffic between 1959 and 1984, a comparative analysis of 1984 serial loan requests was performed, primarily by manipulation of automated request records. The changes in request traffic strongly suggest that the efforts to strengthen regional document delivery through the RML program have been successful and that NLM's collection is now used primarily as a last resort.