PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “LABORATORIES, MEDICAL”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,081 records · Page 60Linked to original sources
PubMed1979

Hypersensitivity pneumonitis in a technician using Pauli's reagent.

A technician working in a medical laboratory used a spray of sodium diazobenzenesulphate (Pauli's reagent) in chromatography. She developed a respiratory illness with both airways obstruction and radiographic and physiological evidence of interstitial pneumonitis. An occupational type of challenge test was followed by both immediate and late bronchial obstructive responses, by a fall in arterial oxygen tension, and by increased radiographic shadowing. Histology of a lung biopsy specimen, a low serum C3, and a postive skin prick test to the reagent suggested that the illness was a hypersensitivity reaction to Pauli's reagent.

Adult↗
PubMed2004

Single-step maternal serum screening for trisomy 21 in the era of combined or integrated screening.

Single-step maternal serum screening (MSS) in the first (1MSS) or second (2MSS) trimester at maternal age > or =35 years was evaluated in the North Belgian region Flanders, where difficulties are encountered in the general introduction of combined or integrated screening algorithms. The fetal aneuploidy screening database of General Medical Laboratory AML in Antwerp was searched for 2MSS tests between 1992 and 1999 (alpha-fetoprotein, beta-human chorionic gonadotropin (beta-HCG) and unconjugated estriol, cut-off 1:300) and for 1MSS tests between 1999 and 2003 (free beta-HCG and pregnancy-associated plasma protein A, cut-off 1:85). At > or =35 years, the detection rate for trisomy 21 (DR) was 93.8% (15/16) for 2MSS and the screen-positive rate (SPR) was 24.5% (504/2061). For 1MSS, these figures were 85.7% (6/7) and 17.7% (109/615) respectively. To detect one trisomy 21, missed by MSS at > or =35 years of age, an additional number of 1,557 and 506 primary invasive procedures would be needed for 2MMS and 1MSS respectively. We conclude that the performance of both single-step 1MSS and 2MSS at maternal age > or =35 years in Flanders is excellent, even without the combination with ultrasound parameters or integration of first and second trimester parameters. The simplicity of both methods allows to consider them valuable options for fetal aneuploidy screening at advanced maternal age, until high quality combined or integrated screening is accessible to all pregnant women in Belgium.

Adult↗
PubMedDate not supplied

Scientific issues related to the cytology proficiency testing regulations.

The member organizations of the CETC feel strongly that there are significant flaws associated with the proposed proficiency test and its implementation. The most immediate modifications include lengthening the required testing interval, utilizing stringently validated and continuously monitored slides, changing the grading scheme and changing the focus of the test from individuals to laboratory level testing, as described above. Integration of new computer-assisted and location-guided screening technologies into the testing protocol is necessary for the testing program to be compliant with the current CLIA law. The regulation also needs to be flexible enough to accommodate new technologies that are implemented in laboratory practice, education and administration of the test. The changes recommended in this document address the most immediate technical and scientific concerns with the current implementation of PT for gynecologic cytology. The CETC will be submitting a subsequent document, following full review of the current regulations, with recommendations for changes, justifications and impact.

Cell Biology↗
PubMedDate not supplied

PAPNET. The human and other dimensions.

OBJECTIVE: To study the effect of specimen preparation and observer variation on the accuracy of interpretation of PAPNET images. STUDY DESIGN: The PAPNET scanner makes use of conventional Papanicolaou-stained smears and presents the cytologist with pictures of selected "abnormal" cells. This minitrial was designed to investigate the human variability in different grades of personnel and to consider any problems caused by the use of conventional smears. RESULTS: The personnel involved consisted of a consultant cytopathologist, a senior chief medical laboratory scientific officer and two senior cytotechnologists, one from another laboratory. Experience with the system ranged from six months to a few years. The best interobserver agreement was found between the senior chief and the senior technologist, who worked in the same laboratory. Majority agreement with the "gold standard" (at least three out of four) was highest for the extremes of "negative" and "high grade" smears. Three high grade smears were "missed" due to the quality of the smears and scantiness of "abnormal" cells. CONCLUSION: Although fatigue in screening is reduced by the interactive mode, it does not overcome the subjectivity of human examination both in review of the dat tape and in microscopic examination of selected cells on the slides. Experience with the method is important, and different background experiences will have an effect. The technical quality of the smear is important since the automated scanner cannot be expected to select abnormal cells if they are absent or obscured for any reason. A monolayer may be the solution, although at greater cost.

Diagnosis, Computer-Assisted↗
PubMedDate not supplied

Fine needle aspiration biopsy of superficial sites in patients with hemostatic defects.

OBJECTIVE: To ascertain the incidence and types of complications of fine needle aspiration biopsies (FNABs) of superficial sites in patients with uncorrected congenital or acquired hemostatic defects. STUDY DESIGN: All patients with hemostatic defects who were seen in a community-based, private fine needle aspiration and medical laboratory practice were identified. Prospectively and retrospectively collected data concerning complications, biopsy findings and laboratory data on the hemostatic defects were collated and analyzed. RESULTS: Twenty-one patients encountered over a period of about nine years were identified. Warfarin sodium therapy was the most common cause of a hemostatic defect (12 patients), and lymph nodes were the most often aspirated structure (7 patients). Other than a small echymosis in one patient, there were no complications. CONCLUSION: FNAB of superficial sites using the technique described is a safe procedure in patients with uncorrected hemostatic defects.

Adult↗
PubMed1998

Accuracy of devices used for self-monitoring of blood glucose.

We measured the inaccuracy of 17 home blood glucose monitors (two visually read, eight colorimetric and seven amperometric). Using strips from a single batch, blood glucose measurements were performed by three medical laboratory technologists on at least 50 capillary blood specimens from patients attending two diabetes clinics. Additional capillary blood was deproteinized and assayed with hexokinase to give a whole blood glucose result. A dedicated glucose analyser was also studied to cross-validate the methodology. At a mean glucose concentration of about 9 mmol/L, monitor readings differed from the reference results by -5.1 to +19.5% with three systems failing to meet the American Diabetes Association guideline for total error of less than 15%. This problem would be alleviated by manufacturers adopting a common policy on calibration and on reporting as a plasma or whole blood value.

Ambulatory Care↗
PubMedDate not supplied

[Toward research in characterization in health care, nursing care and social service. Research connection and date support].

A theory of action for linking clinical practice to research in connection with the development of computer based support in the form of an integrated informational system, is discussed. The aim of the work is toward research into the major subjects studied by nurses, occupational therapists, physical therapists, medical laboratory technologists, social workers, among others. The theory presupposes a conceptual model, which consists of a pyramid of general intrinsic scientific character, and specialized versions of this general model. The model enables one to see major subjects in perspective. This comes about partly in reciprocal communication within the caring process between the receiver of care and different categories of caregivers, partly within the research and developmental work (R&D) deduced from the process or related to it. Moreover, the theory elucidates components which are of importance to the evaluation of the linkage to research as well as R&D.

Clinical Nursing Research↗
PubMed1989

The utilization review program. Essential for hospital survival.

The survival of a health care institution in today's economic climate is dependent on, among other things, the efficiency of its utilization review program. The purpose of this article is to serve as a basic guideline for an institution to develop an adequate utilization review program. It emphasizes that a utilization review program is essential for the economic survival of any health care industry. The utilization review program should be an integrated organization with the support of administration, and the participation of staff physicians, physician advisors, review nurses, and important hospital departments, such as social service, laboratory, medical records, preplanning, and so forth. Following the format presented in this paper, an institution may easily develop a utilization review program. The ideas presented in this paper have been time-proven at our institution. There must be educational programs for physicians on the basics of managing patients according to the prospective payment system and the economic impact physicians can make on the hospital's economic status. These educational presentations must take place as often as necessary to reinforce policy and procedure, and to carry out effective patient management. The utilization review department, as well as the medical staff, must work in close harmony with administration to assist the facility in surviving trying economical times.

Hospital Administration↗
PubMed1993

Current status of tests for periodontal disease.

The methods applied to the diagnosis of periodontal disease are changing. Historically, static clinical and radiographic parameters have formed the basis of the periodontal evaluation. As the limitations of these traditional procedures became clear, several new techniques have been proposed as diagnostic tests for periodontal disease. These tests are based on improved understanding of the pathogenesis of periodontal disease, and can be considered in three categories: assessment of physical changes in the periodontium, the bacterial infection, and the host response to the infection. Several technical questions must be addressed before these tests can be widely utilized. These specific concerns include such matters as the information available from the tests (e.g., Does the test provide a measure of disease severity or identify the site, region, or patient experiencing active disease?), the most appropriate test configurations, the statistical analysis of data from trials examining the accuracy of the tests, and selection of patients who would benefit from these procedures. Last, several important practical issues must be examined before these tests can be expected to gain widespread acceptance. These include familiarization of dental practitioners with the use of diagnostic tests and the medical laboratory, the role of regulatory agencies in determining the claims made by these tests, and the medical/dental insurance benefits provided for these services.

Antibodies, Bacterial↗
PubMed2005

Assessment of physical conditions and current practice in laboratories carrying out sputum smear microscopy in Northwest Ethiopia.

A cross-sectional study was conducted in Northwestern Ethiopia involving 18 health-care institutes in August 2003 to assess the physical conditions and current laboratory practice, pertaining to handling sputum specimens in the health-care laboratories carrying out sputum smear microscopy. A structured and pre-tested questionnaire was used to collect information. The laboratories had an area of less than 25 m(2). None of them had separate rooms or safety cabinets for sputum smear preparation. Only three laboratories used facemasks. QJ;Decontamination of sputum specimens prior to disposal was reported in only two. Incineration as a means of sputum specimen disposal was used in only six laboratories. The physical conditions of the laboratories were found below the standard set by the International Union Against Tuberculoses and Lung Diseases. A large number of sputum specimens continue to be handled, despite the poor conditions and procedures in all the healthcare laboratories. Laboratory safety standards need to be improved, to minimize the risk of infection. In addition, there is an urgent need for education, training and supervision of the staff involved in sputum microscopy.

Clinical Laboratory Techniques↗
PubMed1995

Radiotherapy portal verification: an observer study.

In many radiotherapy facilities radiotherapy portal verification is currently a subjective process based on the visual comparison of a treatment or portal image with a prescription or simulation image. The reliability of this process is unknown. We describe here a study in which 16 observers (oncologists, physicists and therapists) independently evaluated the geometric accuracy of 530 treatment fields on 45 patients. The treatment images were acquired by the BEAMVIEW on-line portal imaging system (Siemens Medical Laboratories, Concord, CA, USA). Illustrative examples of the large variation in observers' assessments of the same field are given. The kappa statistic is used to evaluate the degree of agreement between observers and between on-line (at the treatment unit) and off-line (in a quiet viewing room) assessments. The best interobserver agreement was between the four oncologists contributing to the study although this level of agreement was rated only as "fair". Comparison of on-line and off-line decisions made by therapists exhibited "poor" agreement. This study has provided statistical confirmation of the suspicions of many workers in the field of radiotherapy portal verification, viz that the subjective evaluation of field accuracy is unreliable. However, the degree of unreliability is surprisingly large. The inconsistencies between observers documented in this study need to be clearly acknowledged in the development of protocols for the clinical use of on-line portal imaging systems. Acceptable reliability in radiotherapy portal verification will only be achieved when subjective decision making is eliminated.

Humans↗
PubMed2005

Detection of outliers in reference distributions: performance of Horn's algorithm.

BACKGROUND: Medical laboratory reference data may be contaminated with outliers that should be eliminated before estimation of the reference interval. A statistical test for outliers has been proposed by Paul S. Horn and coworkers (Clin Chem 2001;47:2137-45). The algorithm operates in 2 steps: (a) mathematically transform the original data to approximate a gaussian distribution; and (b) establish detection limits (Tukey fences) based on the central part of the transformed distribution. METHODS: We studied the specificity of Horn's test algorithm (probability of false detection of outliers), using Monte Carlo computer simulations performed on 13 types of probability distributions covering a wide range of positive and negative skewness. Distributions with 3% of the original observations replaced by random outliers were used to also examine the sensitivity of the test (probability of detection of true outliers). Three data transformations were used: the Box and Cox function (used in the original Horn's test), the Manly exponential function, and the John and Draper modulus function. RESULTS: For many of the probability distributions, the specificity of Horn's algorithm was rather poor compared with the theoretical expectation. The cause for such poor performance was at least partially related to remaining nongaussian kurtosis (peakedness). The sensitivity showed great variation, dependent on both the type of underlying distribution and the location of the outliers (upper and/or lower tail). CONCLUSION: Although Horn's algorithm undoubtedly is an improvement compared with older methods for outlier detection, reliable statistical identification of outliers in reference data remains a challenge.

Algorithms↗
PubMed1998

The acute effect of minocycline on the pericardium: experimental and clinical findings.

STUDY OBJECTIVES: To evaluate the acute effect of minocycline on the pericardium in the experimental animal and in the human with malignant pericardial disease. DESIGN: A prospective study in open-chest dogs and in humans. SETTING: Experimental surgery laboratory, medical school; coronary care unit, university hospital. METHODS: Twenty-three open-chest dogs were divided into four groups according to the solution injected intrapericardially: (1) minocycline, 5 mg/kg; (2) minocycline, 10 mg/kg; (3) normal saline solution, 100 mL, followed by minocycline, 10 mg/kg; (4) a mixture of 50 mL of the dog's own blood mixed ex vivo with minocycline, 10 mg/kg to evaluate the effect of rising pH of minocycline solution. The extent of myocardial injury is evaluated by measuring ST-T segment deviation in six standard bipolar leads and in three unipolar electrograms recorded over the left ventricular pericardial surface. The pH of the various minocycline solutions is measured. Nine consecutive patients with malignant cardiac tamponade receiving minocycline intrapericardially are evaluated for the appearance of chest pain and ECG changes. RESULTS: Minocycline (5 and 10 mg/kg) caused marked, transient ST-T segment deviation in all dogs, whether or not saline solution was previously injected into the pericardial sac. Prior mixing of minocycline with blood markedly increased the acidic pH of the minocycline solution and significantly reduced the extent of ST-T segment deviation. Four of nine patients had chest pain during minocycline injection. None had ST-T segment changes. CONCLUSION: Minocycline causes a marked, transient injury to the epicardial-pericardial surface. Our animal and in vitro studies indicate that this acute injury is probably partly related to the acidic pH of the minocycline solution. Our experimental findings suggest that this minocycline-induced injury may be reduced by raising the pH of the solution either ex vivo (eg, by mixing minocycline with previously withdrawn pericardial fluid) or in vivo (eg, by leaving 200 to 300 mL of pericardial fluid prior to minocycline injection). Limited experience in the human with malignant cardiac tamponade indicates that intrapericardial minocycline is usually well tolerated, although severe chest pain may appear.

Animals↗
PubMed1991

Reference materials.

This paper summarizes the practical experience gained in the Federal Republic of Germany in connection with the development and implementation of a national reference system. The National Reference System is set forth in: 1. the New Calibration Act 1986 (Neufassung des Eichgesetzes vom 22. Februar 1985. Bundesgesetzblatt 1985, Teil I, 410-422); 2. the New Weights and Measures Regulations 1988 (Eichordnung vom 12. August 1988. Bundesgesetzblatt 1988, Teil I, 1657-1674). 3. the Guidelines of the Federal Medical Association (1988) for Quality Assurance in Medical Laboratories (Richtlinien der Bundesärztekammer zur Qualitätssicherung in medizinischen Laboratorien vom 16. Januar und 16. Oktober 1987. Deutsches Arzteblatt 85 (11) (1988), A-699--A-712).

Blood Chemical Analysis↗