Laboratories. Medical search

Laboratories: Facilities equipped to carry out investigative procedures.Laboratories, Hospital: Hospital facilities equipped to carry out investigative procedures.Clinical Laboratory Techniques: Techniques used to carry out clinical investigative procedures in the diagnosis and therapy of disease.Animals, Laboratory Medical Laboratory Personnel: Health care professionals, technicians, and assistants staffing LABORATORIES in research or health care facilities.Clinical Laboratory Information Systems: Information systems, usually computer-assisted, designed to store, manipulate, and retrieve information for planning, organizing, directing, and controlling administrative and clinical activities associated with the provision and utilization of clinical laboratory services.Laboratory Personnel: Professionals, technicians, and assistants staffing LABORATORIES.Laboratory Proficiency Testing: Assessments aimed at determining agreement in diagnostic test results among laboratories. Identical survey samples are distributed to participating laboratories, with results stratified according to testing methodologies.Laboratory Animal Science: The science and technology dealing with the procurement, breeding, care, health, and selection of animals used in biomedical research and testing.Quality Control: A system for verifying and maintaining a desired level of quality in a product or process by careful planning, use of proper equipment, continued inspection, and corrective action as required. (Random House Unabridged Dictionary, 2d ed)Chemistry, Clinical: The specialty of ANALYTIC CHEMISTRY applied to assays of physiologically important substances found in blood, urine, tissues, and other biological fluids for the purpose of aiding the physician in making a diagnosis or following therapy.Medical Laboratory Science: The specialty related to the performance of techniques in clinical pathology such as those in hematology, microbiology, and other general clinical laboratory applications.Clinical Laboratory Services: Organized services provided by MEDICAL LABORATORY PERSONNEL for the purpose of carrying out CLINICAL LABORATORY TECHNIQUES used for the diagnosis, treatment, and prevention of disease.Microbiology: The study of microorganisms such as fungi, bacteria, algae, archaea, and viruses.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Laboratories, Dental: Facilities for the performance of services related to dental treatment but not done directly in the patient's mouth.Specimen Handling: Procedures for collecting, preserving, and transporting of specimens sufficiently stable to provide accurate and precise results suitable for clinical interpretation.Pathology, Clinical: A subspecialty of pathology applied to the solution of clinical problems, especially the use of laboratory methods in clinical diagnosis. (Dorland, 28th ed.)Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Evaluation Studies as Topic: Studies determining the effectiveness or value of processes, personnel, and equipment, or the material on conducting such studies. For drugs and devices, CLINICAL TRIALS AS TOPIC; DRUG EVALUATION; and DRUG EVALUATION, PRECLINICAL are available.Reagent Kits, Diagnostic: Commercially prepared reagent sets, with accessory devices, containing all of the major components and literature necessary to perform one or more designated diagnostic tests or procedures. They may be for laboratory or personal use.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Reference Standards: A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Clinical Chemistry Tests: Laboratory tests demonstrating the presence of physiologically significant substances in the blood, urine, tissue, and body fluids with application to the diagnosis or therapy of disease.Bacteriology: The study of the structure, growth, function, genetics, and reproduction of bacteria, and BACTERIAL INFECTIONS.Laboratory Chemicals: Chemicals necessary to perform experimental and/or investigative procedures and for the preparation of drugs and other chemicals.Point-of-Care Systems: Laboratory and other services provided to patients at the bedside. These include diagnostic and laboratory testing using automated information entry.Automation, Laboratory: Controlled operations of analytic or diagnostic processes, or systems by mechanical or electronic devices.Containment of Biohazards: Provision of physical and biological barriers to the dissemination of potentially hazardous biologically active agents (bacteria, viruses, recombinant DNA, etc.). Physical containment involves the use of special equipment, facilities, and procedures to prevent the escape of the agent. Biological containment includes use of immune personnel and the selection of agents and hosts that will minimize the risk should the agent escape the containment facility.Physiology: The biological science concerned with the life-supporting properties, functions, and processes of living organisms or their parts.Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).Blood Chemical Analysis: An examination of chemicals in the blood.Hematologic Tests: Tests used in the analysis of the hemic system.Animal Technicians: Assistants to a veterinarian, biological or biomedical researcher, or other scientist who are engaged in the care and management of animals, and who are trained in basic principles of animal life processes and routine laboratory and animal health care procedures. (Facts on File Dictionary of Health Care Management, 1988)Diagnostic Errors: Incorrect diagnoses after clinical examination or technical diagnostic procedures.Culture Media: Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.Microbiological Techniques: Techniques used in microbiology.Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.False Positive Reactions: Positive test results in subjects who do not possess the attribute for which the test is conducted. The labeling of healthy persons as diseased when screening in the detection of disease. (Last, A Dictionary of Epidemiology, 2d ed)Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Diagnostic Tests, Routine: Diagnostic procedures, such as laboratory tests and x-rays, routinely performed on all individuals or specified categories of individuals in a specified situation, e.g., patients being admitted to the hospital. These include routine tests administered to neonates.Animal Welfare: The protection of animals in laboratories or other specific environments by promoting their health through better nutrition, housing, and care.Pathology Department, Hospital: Hospital department which administers and provides pathology services.Immunoassay: A technique using antibodies for identifying or quantifying a substance. Usually the substance being studied serves as antigen both in antibody production and in measurement of antibody by the test substance.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Hematology: A subspecialty of internal medicine concerned with morphology, physiology, and pathology of the blood and blood-forming tissues.Quality Assurance, Health Care: Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps.Pathology: A specialty concerned with the nature and cause of disease as expressed by changes in cellular or tissue structure and function caused by the disease process.United States Blood Specimen Collection: The taking of a blood sample to determine its character as a whole, to identify levels of its component cells, chemicals, gases, or other constituents, to perform pathological examination, etc.Bacteria: One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Automation: Controlled operation of an apparatus, process, or system by mechanical or electronic devices that take the place of human organs of observation, effort, and decision. (From Webster's Collegiate Dictionary, 1993)Accreditation: Certification as complying with a standard set by non-governmental organizations, applied for by institutions, programs, and facilities on a voluntary basis.Virology: The study of the structure, growth, function, genetics, and reproduction of viruses, and VIRUS DISEASES.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Predictive Value of Tests: In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.Population Surveillance: Ongoing scrutiny of a population (general population, study population, target population, etc.), generally using methods distinguished by their practicability, uniformity, and frequently their rapidity, rather than by complete accuracy.Feces: Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Molecular Diagnostic Techniques: MOLECULAR BIOLOGY techniques used in the diagnosis of disease.Biological Markers: Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.Autoanalysis: Method of analyzing chemicals using automation.Animal Experimentation: The use of animals as investigational subjects.Enzyme-Linked Immunosorbent Assay: An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.Reference Values: The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.Housing, Animal DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Blood: The body fluid that circulates in the vascular system (BLOOD VESSELS). Whole blood includes PLASMA and BLOOD CELLS.Serologic Tests: Diagnostic procedures involving immunoglobulin reactions.False Negative Reactions: Negative test results in subjects who possess the attribute for which the test is conducted. The labeling of diseased persons as healthy when screening in the detection of disease. (Last, A Dictionary of Epidemiology, 2d ed)Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Infant, Newborn: An infant during the first month after birth.Centers for Disease Control and Prevention (U.S.): An agency of the UNITED STATES PUBLIC HEALTH SERVICE that conducts and supports programs for the prevention and control of disease and provides consultation and assistance to health departments and other countries.Rodent Diseases: Diseases of rodents of the order RODENTIA. This term includes diseases of Sciuridae (squirrels), Geomyidae (gophers), Heteromyidae (pouched mice), Castoridae (beavers), Cricetidae (rats and mice), Muridae (Old World rats and mice), Erethizontidae (porcupines), and Caviidae (guinea pigs).Biological Assay: A method of measuring the effects of a biologically active substance using an intermediate in vivo or in vitro tissue or cell model under controlled conditions. It includes virulence studies in animal fetuses in utero, mouse convulsion bioassay of insulin, quantitation of tumor-initiator systems in mouse skin, calculation of potentiating effects of a hormonal factor in an isolated strip of contracting stomach muscle, etc.History, 20th Century: Time period from 1901 through 2000 of the common era.Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.Research: Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. (Webster, 3d ed)Reagent Strips: Narrow pieces of material impregnated or covered with a substance used to produce a chemical reaction. The strips are used in detecting, measuring, producing, etc., other substances. (From Dorland, 28th ed)International Cooperation: The interaction of persons or groups of persons representing various nations in the pursuit of a common goal or interest.Microscopy: The use of instrumentation and techniques for visualizing material and details that cannot be seen by the unaided eye. It is usually done by enlarging images, transmitted by light or electron beams, with optical or magnetic lenses that magnify the entire image field. With scanning microscopy, images are generated by collecting output from the specimen in a point-by-point fashion, on a magnified scale, as it is scanned by a narrow beam of light or electrons, a laser, a conductive probe, or a topographical probe.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Drug Monitoring: The process of observing, recording, or detecting the effects of a chemical substance administered to an individual therapeutically or diagnostically.Mycobacterium tuberculosis: A species of gram-positive, aerobic bacteria that produces TUBERCULOSIS in humans, other primates, CATTLE; DOGS; and some other animals which have contact with humans. Growth tends to be in serpentine, cordlike masses in which the bacilli show a parallel orientation.Methods: A series of steps taken in order to conduct research.Histology: The study of the structure of various TISSUES of organisms on a microscopic level.Occupational Exposure: The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.Genotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Bacterial Infections: Infections by bacteria, general or unspecified.United States Public Health Service: A constituent organization of the DEPARTMENT OF HEALTH AND HUMAN SERVICES concerned with protecting and improving the health of the nation.Bacterial Typing Techniques: Procedures for identifying types and strains of bacteria. The most frequently employed typing systems are BACTERIOPHAGE TYPING and SEROTYPING as well as bacteriocin typing and biotyping.Physicians' Offices: The room or rooms in which the physician and staff provide patient care. The offices include all rooms in the physician's office suite.Seasons: Divisions of the year according to some regularly recurrent phenomena usually astronomical or climatic. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Enterobacteriaceae: A family of gram-negative, facultatively anaerobic, rod-shaped bacteria that do not form endospores. Its organisms are distributed worldwide with some being saprophytes and others being plant and animal parasites. Many species are of considerable economic importance due to their pathogenic effects on agriculture and livestock.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Candida: A genus of yeast-like mitosporic Saccharomycetales fungi characterized by producing yeast cells, mycelia, pseudomycelia, and blastophores. It is commonly part of the normal flora of the skin, mouth, intestinal tract, and vagina, but can cause a variety of infections, including CANDIDIASIS; ONYCHOMYCOSIS; vulvovaginal candidiasis (CANDIDIASIS, VULVOVAGINAL), and thrush (see CANDIDIASIS, ORAL). (From Dorland, 28th ed)Logical Observation Identifiers Names and Codes: A vocabulary database of universal identifiers for laboratory and clinical test results. Its purpose is to facilitate the exchange and pooling of results for clinical care, outcomes management, and research. It is produced by the Regenstrief Institute. (LOINC and RELMA [Internet]. Indianapolis: The Regenstrief Institute; c1995-2001 [cited 2002 Apr 2]. Available from http://www.regenstrief.org/loinc)Diagnostic Services: Organized services for the purpose of providing diagnosis to promote and maintain health.Animal Diseases Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Computers Agar: A complex sulfated polymer of galactose units, extracted from Gelidium cartilagineum, Gracilaria confervoides, and related red algae. It is used as a gel in the preparation of solid culture media for microorganisms, as a bulk laxative, in making emulsions, and as a supporting medium for immunodiffusion and immunoelectrophoresis.Parasitology: The study of parasites and PARASITIC DISEASES.Drug Resistance, Microbial: The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Urine: Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the URETHRA.Calibration: Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.Mycology: The study of the structure, growth, function, genetics, and reproduction of fungi, and MYCOSES.Animals, Wild: Animals considered to be wild or feral or not adapted for domestic use. It does not include wild animals in zoos for which ANIMALS, ZOO is available.Severity of Illness Index: Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.Immunoenzyme Techniques: Immunologic techniques based on the use of: (1) enzyme-antibody conjugates; (2) enzyme-antigen conjugates; (3) antienzyme antibody followed by its homologous enzyme; or (4) enzyme-antienzyme complexes. These are used histologically for visualizing or labeling tissue specimens.Veterinary Medicine: The medical science concerned with the prevention, diagnosis, and treatment of diseases in animals.Equipment Contamination: The presence of an infectious agent on instruments, prostheses, or other inanimate articles.World Health Organization: A specialized agency of the United Nations designed as a coordinating authority on international health work; its aim is to promote the attainment of the highest possible level of health by all peoples.Forensic Medicine: The application of medical knowledge to questions of law.History, 21st Century: Time period from 2001 through 2100 of the common era.Rodenticides: Substances used to destroy or inhibit the action of rats, mice, or other rodents.Insecticides: Pesticides designed to control insects that are harmful to man. The insects may be directly harmful, as those acting as disease vectors, or indirectly harmful, as destroyers of crops, food products, or textile fabrics.Larva: Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.Europe Pest Control, Biological: Use of naturally-occuring or genetically-engineered organisms to reduce or eliminate populations of pests.Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Brazil Follow-Up Studies: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.Water Microbiology: The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.Serotyping: Process of determining and distinguishing species of bacteria or viruses based on antigens they share.Nucleic Acid Amplification Techniques: Laboratory techniques that involve the in-vitro synthesis of many copies of DNA or RNA from one original template.Diagnostic Techniques and Procedures: Methods, procedures, and tests performed to diagnose disease, disordered function, or disability.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Immunologic Tests: Immunologic techniques involved in diagnosis.Costs and Cost Analysis: Absolute, comparative, or differential costs pertaining to services, institutions, resources, etc., or the analysis and study of these costs.Software: Sequential operating programs and data which instruct the functioning of a digital computer.Disease Notification: Notification or reporting by a physician or other health care provider of the occurrence of specified contagious diseases such as tuberculosis and HIV infections to designated public health agencies. The United States system of reporting notifiable diseases evolved from the Quarantine Act of 1878, which authorized the US Public Health Service to collect morbidity data on cholera, smallpox, and yellow fever; each state in the US has its own list of notifiable diseases and depends largely on reporting by the individual health care provider. (From Segen, Dictionary of Modern Medicine, 1992)Incidence: The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases, new or old, in the population at a given time.Colorimetry: Any technique by which an unknown color is evaluated in terms of standard colors. The technique may be visual, photoelectric, or indirect by means of spectrophotometry. It is used in chemistry and physics. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Environmental Monitoring: The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Bacterial Proteins: Proteins found in any species of bacterium.Antifungal Agents: Substances that destroy fungi by suppressing their ability to grow or reproduce. They differ from FUNGICIDES, INDUSTRIAL because they defend against fungi present in human or animal tissues.Age Factors: Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.Blood Sedimentation: Measurement of rate of settling of erythrocytes in anticoagulated blood.Tuberculosis: Any of the infectious diseases of man and other animals caused by species of MYCOBACTERIUM.Oviposition: The process of laying or shedding fully developed eggs (OVA) from the female body. The term is usually used for certain INSECTS or FISHES with an organ called ovipositor where eggs are stored or deposited before expulsion from the body.Immunoglobulin M: A class of immunoglobulin bearing mu chains (IMMUNOGLOBULIN MU-CHAINS). IgM can fix COMPLEMENT. The name comes from its high molecular weight and originally being called a macroglobulin.Reproduction: The total process by which organisms produce offspring. (Stedman, 25th ed)Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.HIV Infections: Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, thru AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).Teaching: The educational process of instructing.Sputum: Material coughed up from the lungs and expectorated via the mouth. It contains MUCUS, cellular debris, and microorganisms. It may also contain blood or pus.Cohort Studies: Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Guidelines as Topic: A systematic statement of policy rules or principles. Guidelines may be developed by government agencies at any level, institutions, professional societies, governing boards, or by convening expert panels. The text may be cursive or in outline form but is generally a comprehensive guide to problems and approaches in any field of activity. For guidelines in the field of health care and clinical medicine, PRACTICE GUIDELINES AS TOPIC is available.Genetic Testing: Detection of a MUTATION; GENOTYPE; KARYOTYPE; or specific ALLELES associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing.Equipment Design: Methods of creating machines and devices.Automatic Data Processing: Data processing largely performed by automatic means.Toxicology: The science concerned with the detection, chemical composition, and biological action of toxic substances or poisons and the treatment and prevention of toxic manifestations.Agglutination Tests: Tests that are dependent on the clumping of cells, microorganisms, or particles when mixed with specific antiserum. (From Stedman, 26th ed)Urinalysis: Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Workflow: Description of pattern of recurrent functions or procedures frequently found in organizational processes, such as notification, decision, and action.Acute Disease: Disease having a short and relatively severe course.Dental Technicians: Individuals responsible for fabrication of dental appliances.Drug Resistance, Bacterial: The ability of bacteria to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Prothrombin Time: Clotting time of PLASMA recalcified in the presence of excess TISSUE THROMBOPLASTIN. Factors measured are FIBRINOGEN; PROTHROMBIN; FACTOR V; FACTOR VII; and FACTOR X. It is used for monitoring anticoagulant therapy with COUMARINS.Andrology: A scientific or medical discipline concerning the study of male reproductive biology, diseases of the male genital organs, and male infertility. Major areas of interest include ENDOCRINOLOGY; SPERMATOGENESIS; semen analysis; FERTILIZATION; CONTRACEPTION; and CRYOPRESERVATION.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Blood Cell Count: The number of LEUKOCYTES and ERYTHROCYTES per unit volume in a sample of venous BLOOD. A complete blood count (CBC) also includes measurement of the HEMOGLOBIN; HEMATOCRIT; and ERYTHROCYTE INDICES.Sentinel Surveillance: Monitoring of rate of occurrence of specific conditions to assess the stability or change in health levels of a population. It is also the study of disease rates in a specific cohort such as in a geographic area or population subgroup to estimate trends in a larger population. (From Last, Dictionary of Epidemiology, 2d ed)Filtration: A process of separating particulate matter from a fluid, such as air or a liquid, by passing the fluid carrier through a medium that will not pass the particulates. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Statistics as Topic: The science and art of collecting, summarizing, and analyzing data that are subject to random variation. The term is also applied to the data themselves and to the summarization of the data.Cross-Sectional Studies: Studies in which the presence or absence of disease or other health-related variables are determined in each member of the study population or in a representative sample at one particular time. This contrasts with LONGITUDINAL STUDIES which are followed over a period of time.Public Health: Branch of medicine concerned with the prevention and control of disease and disability, and the promotion of physical and mental health of the population on the international, national, state, or municipal level.Feeding Behavior: Behavioral responses or sequences associated with eating including modes of feeding, rhythmic patterns of eating, and time intervals.Animal Husbandry: The science of breeding, feeding and care of domestic animals; includes housing and nutrition.Bioterrorism: The use of biological agents in TERRORISM. This includes the malevolent use of BACTERIA; VIRUSES; or other BIOLOGICAL TOXINS against people, ANIMALS; or PLANTS.Genetic Variation: Genotypic differences observed among individuals in a population.Databases, Factual: Extensive collections, reputedly complete, of facts and data garnered from material of a specialized subject area and made available for analysis and application. The collection can be automated by various contemporary methods for retrieval. The concept should be differentiated from DATABASES, BIBLIOGRAPHIC which is restricted to collections of bibliographic references.Immunoglobulin G: The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.Chemistry Techniques, Analytical: Methodologies used for the isolation, identification, detection, and quantitation of chemical substances.Prognosis: A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.Fungi: A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including MUSHROOMS; YEASTS; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies.User-Computer Interface: The portion of an interactive computer program that issues messages to and receives commands from a user.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Syphilis Serodiagnosis: Serologic tests for syphilis.Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Risk Assessment: The qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences. (Last, Dictionary of Epidemiology, 1988)Environment, Controlled: A state in which the environs of hospitals, laboratories, domestic and animal housing, work places, spacecraft, and other surroundings are under technological control with regard to air conditioning, heating, lighting, humidity, ventilation, and other ambient features. The concept includes control of atmospheric composition. (From Jane's Aerospace Dictionary, 3d ed)Great BritainData Collection: Systematic gathering of data for a particular purpose from various sources, including questionnaires, interviews, observation, existing records, and electronic devices. The process is usually preliminary to statistical analysis of the data.Hospitals, University: Hospitals maintained by a university for the teaching of medical students, postgraduate training programs, and clinical research.Viruses: Minute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Mass Screening: Organized periodic procedures performed on large groups of people for the purpose of detecting disease.Aedes: A genus of mosquitoes (CULICIDAE) frequently found in tropical and subtropical regions. YELLOW FEVER and DENGUE are two of the diseases that can be transmitted by species of this genus.Behavior, Animal: The observable response an animal makes to any situation.

European interlaboratory comparison of breath 13CO2 analysis. (1/1696)

The BIOMED I programme Stable Isotopes in Gastroenterology and Nutrition (SIGN) has focused upon evaluation and standardisation of stable isotope breath tests using 13C labelled substrates. The programme dealt with comparison of 13C substrates, test meals, test conditions, analysis techniques, and calculation procedures. Analytical techniques applied for 13CO2 analysis were evaluated by taking an inventory of instrumentation, calibration protocols, and analysis procedures. Two ring tests were initiated measuring 13C abundances of carbonate materials. Evaluating the data it was found that seven different models of isotope ratio mass spectrometers (IRMS) were used by the participants applying both the dual inlet system and the continuous flow configuration. Eight different brands of certified 13C reference materials were used with a 13C abundance varying from delta 13CPDB -37.2 to +2.0/1000. CO2 was liberated from certified material by three techniques and different working standards were used varying from -47.4 to +0.4/1000 in their delta 13CPDB value. The standard deviations (SDs) found for all measurements by all participants were 0.25/1000 and 0.50/1000 for two carbonates used in the ring tests. The individual variation for the single participants varied from 0.02 /1000 (dual inlet system) to 0.14/1000 (continuous flow system). The measurement of the difference between two carbonates showed a SD of 0.33/1000 calculated for all participants. Internal precision of IRMS as indicated by the specifications of the different instrument suppliers is < 0.3/1000 for continuous flow systems. In this respect it can be concluded that all participants are working well within the instrument specifications even including sample preparation. Increased overall interlaboratory variation is therefore likely to be due to non-instrumental conditions. It is possible that consistent differences in sample handling leading to isotope fractionation are the causes for interlaboratory variation. Breath analysis does not require sample preparation. As such, interlaboratory variation will be less than observed for the carbonate samples and within the range indicated as internal precision for continuous flow instruments. From this it is concluded that pure analytical interlaboratory variation is acceptable despite the many differences in instrumentation and analytical protocols. Coordinated metabolic studies appear possible, in which different European laboratories perform 13CO2 analysis. Evaluation of compatibility of the analytical systems remains advisable, however. (+info)

Analyte comparisons between 2 clinical chemistry analyzers. (2/1696)

The purpose of this study was to assess agreement between a wet reagent and a dry reagent analyzer. Thirteen analytes (albumin, globulin, alkaline phosphatase, alanine aminotransferase, amylase, urea nitrogen, calcium, cholesterol, creatinine, glucose, potassium, total bilirubin, and total protein) for both canine and feline serum were evaluated. Concordance correlations, linear regression, and plots of difference against mean were used to analyze the data. Concordance correlations were excellent for 8 of 13 analytes (r > or = 0.90); the correlations for albumin, potassium, and calcium were clinically unreliable. The linear regression analysis revealed that several analytes had slopes significantly different from unity, which was likely related to methodological differences. Compared to the wet reagent analyzer, the dry reagent analyzer showed excellent agreement for alkaline phosphatase, alanine aminotransferase, amylase (feline), urea nitrogen, cholesterol, creatinine, glucose, total bilirubin (canine), and total protein. However, it showed only slight to substantial agreement for amylase (canine), calcium, albumin, potassium, and total bilirubin (feline). (+info)

Pseudoepidemic of Aspergillus niger infections traced to specimen contamination in the microbiology laboratory. (3/1696)

We report a pseudo-outbreak of Aspergillus niger that followed building construction in our clinical microbiology laboratory. Because outbreaks of invasive aspergillosis have been linked to hospital construction, strategies to minimize dust in patient care areas are common practice. We illustrate that the impact of false-positive cultures on patient care should compel laboratories to prevent specimen contamination during construction. (+info)

Preliminary external quality assessment for the biological monitoring of carbon disulfide with urinary 2-thiothiazolidine-4-carboxylic acid. (4/1696)

Four laboratories have participated in an external quality control assessment for the determination of 2-thiothiazolidine-4-carboxylic acid (TTCA). TTCA is used as a biomarker for exposure to CS2. Thirteen different urine samples were analyzed by each laboratory. Ten of these were spiked with known amounts of TTCA, and had either a high or intermediate creatinine content. Two samples without any TTCA were used as controls and one sample was a pool of samples of urine from five employees occupationally exposed to CS2. The latter had unknown TTCA content. For each sample, TTCA and creatinine concentration were determined. The samples were supplied in three consecutive deliveries. Several samples were offered more than once. Thus, within-laboratory variability could be established for creatinine and TTCA determination and accuracy could be determined for TTCA analysis. Within-laboratory variability was low for all laboratories for creatinine, although laboratory D seemed to have a slight downward bias. Accuracy for TTCA was good for all laboratories. No significant mean deviation from the expected TTCA value was encountered. There does not seem to be any clear influence of the TTCA concentration level of the samples on the accuracy and within-laboratory variability. Two of the four laboratories (A and C) showed lower within-laboratory variability than the other two for TTCA, although coefficients of variation between replicated samples are high for these two laboratories as well. The laboratory giving the best accuracy, gave the highest within-laboratory variability. A non-systematic, random error is probably the source of this. The results of this preliminary study indicate that analysis of TTCA, although regarded as an established biomarker, can give biases and thus negatively interfere with inferred dose-effect or dose-response relationships in occupational epidemiology. (+info)

Experience with external quality control in spermatology. (5/1696)

Results are presented from participation in an external quality control (EQC) programme for semen analysis (UK NEQAS). Formalin-fixed semen samples and videotapes of motile spermatozoa were distributed four times a year over a 3-4 year period. Over the entire period there was close agreement for sperm concentration with, initially, the average of values from the other groups participating in the scheme, and later, values designated as reference values obtained from six laboratories of several chosen that consistently agreed with each other. The initial underestimation of the percentage of normal forms was abolished at the time of change in derivation of designated values and this largely eliminated the difference to establish closer agreement with the designated values. A consistent bias in the assessment of different categories of progressive sperm motility appeared to be resolved by a conscious decision to consider most spermatozoa as grade b and the exceptions as grade a, rather than the converse. Feedback of results to the technicians of the laboratory participating in an external quality control programme leads to reappraisal of subjective evaluation and to harmonization of results between laboratories. (+info)

emm typing and validation of provisional M types for group A streptococci. (6/1696)

This report discusses the following issues related to typing of group A streptococci (GAS): The development and use of the 5' emm variable region sequencing (emm typing) in relation to the existing serologic typing system; the designation of emm types in relation to M types; a system for validation of new emm types; criteria for validation of provisional M types to new M-types; a list of reference type cultures for each of the M-type or emm-type strains of GAS; the results of the first culture exchange program for a quality control testing system among the national and World Health Organization collaborating centers for streptococci; and dissemination of new approaches to typing of GAS to the international streptococcal community. (+info)

A national survey of practice patterns in the noninvasive diagnosis of deep venous thrombosis. (7/1696)

PURPOSE: Recent studies have recommended unilateral venous duplex scanning for the diagnosis of deep venous thrombosis (DVT) in patients who are unilaterally symptomatic. Vascular laboratory accreditation standards, however, imply that bilateral leg scanning should be performed. We examined whether actual practice patterns have evolved toward limited unilateral scanning in such patients. METHODS: A questionnaire was mailed to all 808 vascular laboratories in the United States that were accredited by the Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL). To encourage candid responses, the questionnaires were numerically coded and confidentiality was assured. RESULTS: A total of 608 questionnaires (75%) were completed and returned. Most of the respondents (442; 73%) were either community-hospital or office-based laboratories, and the remaining 163 (27%) were university or affiliated-hospital laboratories. Most of the laboratories (460; 76%) had been in existence for 9 years or more, and 65% had been ICAVL-accredited in venous studies for 3 years or more. Board-certified vascular surgeons were the medical directors in 54% of the laboratories. Duplex ultrasound scanning was the diagnostic method used by 98% of the laboratories. In patients with unilateral symptoms, 75% of the laboratories did not routinely scan both legs for DVT. A large majority (75%) believe that bilateral scanning is not clinically indicated. Only 57 laboratories (14%) recalled having patients return with a DVT in the previously unscanned leg, with 93% of these laboratories reporting between one and five such patients. This observation correlated with larger volumes of venous studies performed by those laboratories (P <.05). Similarly, only 52 laboratories (12%) recalled having patients return with subsequent pulmonary emboli. Of these laboratories, only five reported proximal DVT in the previously unscanned legs of such patients. Of all these laboratories, therefore, only 1% (5 of 443) have potentially missed the diagnosis of a DVT that caused a preventable pulmonary embolus with such a policy. Among those laboratories that always perform bilateral examinations, 41% do so because of habit. Most (61%) of the laboratories that perform bilateral scanning would do unilateral scanning if it were specifically approved by ICAVL. CONCLUSION: Three quarters of the ICAVL-accredited vascular laboratories perform limited single-extremity scanning for the diagnosis of DVT in patients with unilateral symptoms. This broad clinical experience suggests that this practice is widespread in selected patients. Clinical protocols should be established to provide guidelines for local laboratory implementation. (+info)

The Calgary Biofilm Device: new technology for rapid determination of antibiotic susceptibilities of bacterial biofilms. (8/1696)

Determination of the MIC, based on the activities of antibiotics against planktonic bacteria, is the standard assay for antibiotic susceptibility testing. Adherent bacterial populations (biofilms) present with an innate lack of antibiotic susceptibility not seen in the same bacteria grown as planktonic populations. The Calgary Biofilm Device (CBD) is described as a new technology for the rapid and reproducible assay of biofilm susceptibilities to antibiotics. The CBD produces 96 equivalent biofilms for the assay of antibiotic susceptibilities by the standard 96-well technology. Biofilm formation was followed by quantitative microbiology and scanning electron microscopy. Susceptibility to a standard group of antibiotics was determined for National Committee for Clinical Laboratory Standards (NCCLS) reference strains: Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Staphylococcus aureus ATCC 29213. Growth curves demonstrated that biofilms of a predetermined size could be formed on the CBD at specific time points and, furthermore, that no significant difference (P > 0.1) was seen between biofilms formed on each of the 96 pegs. The antibiotic susceptibilities for planktonic populations obtained by the NCCLS method or from the CBD were similar. Minimal biofilm eradication concentrations, derived by using the CBD, demonstrated that for biofilms of the same organisms, 100 to 1,000 times the concentration of a certain antibiotic were often required for the antibiotic to be effective, while other antibiotics were found to be effective at the MICs. The CBD offers a new technology for the rational selection of antibiotics effective against microbial biofilms and for the screening of new effective antibiotic compounds. (+info)