Pathology and laboratory medicine
Article Abstract:
Pathologists traditionally examined tissues under the microscope to provide a definitive diagnosis of many different diseases, including cancer. Today, the pathologist is also likely to examine very small biopsy specimens and cells obtained by fine-needle aspiration biopsy. Early diagnosis of cancerous lesions must be made to provide prompt treatment. The traditional dyes used to stain tissues for examination have been supplemented in recent years by antibody techniques that can precisely detect specific substances. Molecular genetic techniques may also be used to demonstrate whether cells in a tissue specimen contain specific genes; this method is particularly useful to evaluate specimens for viral infection. Even when no other signs of viral infection are present, it is often possible to demonstrate the presence of viral genes within cells. Another new tool for the pathologist is DNA measurement. Using either flow cytometry, which measures DNA cell-by-cell in a suspension of floating cells, or image analysis, in which the DNA content of cells on a microscopic slide is measured, pathologists can obtain an estimate of the distribution of DNA contents within the cells of a specimen. This information is particularly important in determining the prognosis of cancer, and may identify patients who do not require aggressive treatment, as well as those for whom the conventional treatments are likely to be inadequate. Computers are also used in the image analysis laboratory; automated techniques are now being applied to the routine screening of specimens. Thousands of woman have routine Pap smears performed to screen for cervical cancer. An automatic image analysis computer can accurately view thousands of slides and alert the pathologist to unusual specimens that require further examination. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: JAMA, The Journal of the American Medical Association
Subject: Health
ISSN: 0098-7484
Year: 1991
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Pathology and laboratory medicine
Article Abstract:
Diagnostic techniques based on biotechnology and analysis of the placenta are two areas of research in the field of pathology and laboratory medicine. Polymerase chain reaction (PCR) allows scientists to make many copies of DNA or RNA from very small samples. The presence of gram-negative bacteria in the blood is a sure way to diagnose septic shock. Continuous, automated blood culture systems may allow easier detection. Pathologist are also developing tests for genes responsible for cancer cell multiple drug resistance (MDR). The placenta is being examined more thoroughly to determine the association between pregnancy risk, the condition of the placenta and a child's growth and development. Genetic analysis can show the presence of some genetic disorders when a human embryo is in the eight-cell stage. Parents can make decisions without going through the trauma of a pregnancy which might have to be ended.
Publication Name: JAMA, The Journal of the American Medical Association
Subject: Health
ISSN: 0098-7484
Year: 1992
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Pathology and laboratory medicine
Article Abstract:
Automation is aiding laboratories in holding the line on costs and reducing sample handling errors. The development of biosensors has spurred the design of alternate-site laboratory instruments. These instruments allow for individual sample analysis and continuous monitoring of glucose, carbon dioxide, and blood oxygen, but are also expensive. The proliferation of infectious diseases, such as mycobacterium tuberculosis, is prompting new studies of how to diagnose and track microbial diseases. Molecular biology approaches are being used, among them polymerase chain reaction (PCR), to identify strains. PCR is also used to diagnose hepatitis B infections and HIV.
Publication Name: JAMA, The Journal of the American Medical Association
Subject: Health
ISSN: 0098-7484
Year: 1995
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