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Biomedical subjects

R K Wertz

Publications and source records attributed to R K Wertz.

At least 19 recordsLinked to original sources

CD-ROM. A new advance in medical information retrieval.

The massive production of medical information is being met by new technologies for storing and retrieving knowledge. Recent years have witnessed the maturation of time-sharing information utilities into a full-blown industry. In medicine these services have provided bibliographic information but have recently expanded to full-text availability of journals and books. Now optical storage technology, most conspicuously the compact disk read only memory (CD-ROM), provides similar massive information storage and retrieval affordable to microcomputer users. Such devices might replace many of the functions of time-sharing.

Computers↗

What every pathologist should know and be able to do in laboratory data processing and computers: systems analysis and planning.

This article is the fourth in a five part series on laboratory data processing and computers. Preceding the article are enabling and performance objectives, defined by the Laboratory Computer Applications and Data Processing Committee, for the systems analysis and planning competency area. Following the article are questions with which readers can test their understanding of the material.

Computers↗

Computerized interpretation of minimum inhibitory concentration antimicrobic susceptibility testing.

Quantitative antimicrobic susceptibility tests by determining the minimum inhibitory concentration (MIC) are becoming more and more prevalent in United States laboratories. Interpretation of MIC values is complex and should be considered as part of the laboratory service. This communication provides a simple computerized scheme for MIC interpretation that has been used for more than three years in the authors' laboratories. This computer algorithm provides a semigraphic output documenting relative susceptibility for a matrix of various dosages and sites of the body. Additional features, such as consideration of beta-lactamase production for Staphylococcus aureus and toxic levels for aminoglycosides, are considered in this algorithm. In addition, the authors present a compendium of achievable levels for a comprehensive list of antimicrobics, together with literature reference documentation.

Anti-Bacterial Agents↗

What pathologists should know and be able to do in laboratory data processing and computers: peripheral devices and storages.

This article is the second in a five-part educational series on laboratory data processing and computers. The authors describe the major components of peripheral storage and the limitations of input/output devices, and analyze in terms of laboratory workflow the type and placement of input/output devices. Preceding the article are competency areas and performance objectives, defined by the Laboratory Computer Applications and Data Processing Committee. Following the article are questions with which readers can test their understanding of the material. Next month the authors will focus on software.

Computers↗

The current status of laboratory data processing.

The CAP Laboratory Computer Applications and Data Processing Committee surveyed recently a random sample of participants in the CAP Survey Program to determine the current status of data processing in clinical laboratories. The results of the study, which confirm that laboratory computerization is a still new but growing movement, are presented in the following pages.

Computers↗

A review of platelet counting performance in the United States.

An interlaboratory comparison of platelet counting in clinical hematology laboratories in the United States is presented. Comparison of performance during the 1979 CAP platelet survey with performance in 1976 indicates a significant improvement in accuracy and interlaboratory precision. The calibration of instruments by clinical laboratories remains as a source of bias. Recommendations for calibration are presented.

Decision Making↗

A critical analysis of platelet counting methods.

A careful analysis of platelet counting methods, including an assessment of accuracy, was done using data from the College of American Pathologists Comprehensive Hematology Survey preserved platelet suspension specimen (H-32-1976). Comparisons between methods suggest systematic biases probably related to the calibration methods used for automated instruments. Falsely elevated counts occurred with manual methods and one light-dispersion system. Methods for calibration and continuing quality assurance of platelet counting are proposed.

Automation↗

An electron microscopy study of vitally stained single cells irradiated with a ruby laser microbeam.

An electron microscope study has been made of vitally stained single cells whose cytoplasm has been subjected to a localized ruby laser microbeam. Light and moderate laser absorption (the resultant of stain concentration and laser energy density) produced restricted selective damage of mitochondria in cells stained with Janus green B; heavy laser absorption resulted in mitochondrial damage, as well as in nonselective interaction with other cell structures. With four other basic vital stains, the polysomes, ergastoplasm, mitochondria and other organelles at the irradiated site were uniformly damaged. Unstained cells showed no morphological alterations. With light primary damage (that restricted to the irradiation site), no secondary effects of the incident radiation were observed. With moderate primary damage, however, secondary damage of the mitochondria in the unirradiated cell portions was produced, which was reversible within 4 hr after irradiation. Heavy primary lesions caused severe secondary alteration of all cell structures that was irreversible and cell death occurred within 2 hr. Surviving cells examined 24 hr after light and moderate irradiation could not be distinguished from unirradiated controls. The possible mechanisms involved in the production of laser-induced cellular alterations are discussed.

Animals↗