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At least 343 records · Page 19Linked to original sources
PubMed1987

A simple quantitative analysis system for coronary cineangiograms using a personal computer.

We have developed a simple quantitative analysis system for coronary cineangiograms using a personal computer and a standard projector-video camera system. The selected frame of cinefilm was projected onto the target area of a CCD video camera. To decrease spatial fluctuations due to quantum noise, the digital data were smoothed spatially by applying a moving averaged filter and a median filter. Following the smoothing process, the digital data with gray level were transformed to binary data by quantifying the threshold property of their gray level. To minimize the geometric influence, mainly pincushion effect, a cinefilm of a 1 cm grid was placed against the input screen of the image intensifier to correct the distortion by using 3rd degree polynomials. The accuracy of the contour detection procedure was validated on the basis of phantom models filled with a contrast medium. Despite the potential influence of many radiographic variables on computerized diameter measurements, the overall accuracy was found to be 0.26-0.33 mm over a wide range of clinically relevant artery diameters and radiographic conditions. Using this system we demonstrated one method of examining the effects of acetylcholine and nitroglycerin on coronary artery diameter in adult humans.

Acetylcholine↗
PubMed1983

Linear systems analysis of infant visual pattern preferences.

Karmel's check-pattern preference data for 13-week-old infants were reanalyzed using linear systems analysis. The two-dimensional Fourier amplitude spectrum was calculated for each of his eight checkerboard and random check patterns. The mean contrast sensitivity data for 3-month-old infants of Banks and Salapatek and the spatial frequency amplitudes of the patterns were used to derive three metrics to predict the looking times observed by Karmel. One was based on the sensitivity of the visual system to the single pattern component highest above threshold (maximum amplitude), the second was based on the total amount of pattern energy above threshold (total summation), and the third was based on the maximum amplitude with summation over nearby spatial frequency components (limited summation). The predictive power of the maximum amplitude and the total summation metrics depended on whether the pattern type was checkerboard or random check. The limited summation metric predicted looking times well for both pattern types. A linear function of the logarithm of the limited summation metric accounted for 91% of the total variance in looking time.

Fixation, Ocular↗
PubMed1981

[Testing experience with an automatic ECG analysis system in the cardiology clinic].

An original system of automated analysis of electrocardiosignals has been developed on the basis of computer EC-1022. The system consists of an appliance for the collection and recording of the electrocardiosignals (ECS), an arrangement for the input and output of ECS into the computer and the basic programs input, identification, measurement, rhythm, contour, formation, search, dispatcher. The system has been tested in a cardiological clinic. The computer and the medical conclusions coincided in 82% of cases.

Clinical Trials as Topic↗
PubMed1991

A living systems analysis of organizational pathology.

Organizations have essentially the same subsystem processes as living systems at other levels. All of them adjust subsystem variables to changing environmental and internal circumstances. Pathology exists in any system when a subsystem variable remains out of its steady-state range for an extended period. The same classes of pathology can be found at all levels. This article analyzes the various forms of pathology that exist in living systems at the level of organizations and describes living systems process analysis. Studies of several types of organizations including U.S. Army battalions, a corporation, a hospital, and a possible space station or lunar base, are discussed.

Animals↗
PubMed1978

The role of operations research and systems analysis in holding down the costs of hospitals and clinics.

In the past, medical care facilities have concentrated primarily on professional clinical evaluation. With the cost of treatment rising rapidly, it is becoming increasingly important to critically review and analyze our delivery systems so that scarce resources can be used optimally. In this paper the applications of operations research (O.R.) and systems analysis techniques that have been employed successfully in private industry are explored to find ways to improve clinical operations and hold costs down.

Costs and Cost Analysis↗
PubMed1979

Detection of suspicious cells and rejection of artefacts in cervical cytology using the Leyden Television Analysis System.

In slide based automation of cervical cytology the first stage of analysis involves finding possibly suspicious cells, or areas on the slide with these types of cells. By using a television based system such as the Leyden Television Analysis System (LEYTAS), a number of detection methods can be applied to rapidly screen a large number of fields automatically for suspicious cells. In this paper, results using a parameter based on increased nuclear DNA content of cells are given and a second detection method based on a chromatin pattern feature, called chromatin contrast, is discussed. Two blind trials on 41 positive and 22 negative cervical slides, using the Leyden Television Analysis System to detect suspicious cells with an increased nuclear DNA content, were promising. In 1 of the 41 positive cases no suspicious cells were found. In the negative specimens, suspicious cells were detected in 1 of 9 cases and 1 of 13 cases, with the two detection parameters investigated. These findings are discussed and some automatic artefact rejection procedures with preliminary results are given.

Cervix Uteri↗
PubMed2000

Quantification of angiogenesis by a computerized image analysis system in renal cell carcinoma.

OBJECTIVE: To ascertain whether tumor angiogenesis quantitated by a computerized image analysis system correlates with clinical outcome in renal cell carcinoma. STUDY DESIGN: Microvessels were immunohistochemically labeled with antibodies to CD34 in sections from 62 cases of renal cell carcinoma. Computerized image analysis was used to evaluate the mean microvessel count (MMC) and mean percentage microvessel area (MPMA). RESULTS: MMC ranged from 19.3 to 315.0, while MPMA was 0.6-17.9%. There was a highly significant correlation between MMC and MPMA (r = .867, P < .01). Although MMC and MPMA decreased with increasing nuclear grade and TNM stage, this difference failed to achieve statistical significance. No statistically significant differences in survival were found for MMC or MPMA. CONCLUSION: Our results indicate that computerized image analysis can evaluate accurately tumor angiogenesis, but tumor angiogenesis in renal cell carcinoma does not provide significant prognostic information in renal cell carcinoma.

Adult↗
PubMed2005

An on-membrane quantitative analysis system for glycyrrhizin in licorice roots and traditional Chinese medicines.

An on-membrane quantitative analysis system has been developed for determining glycyrrhizin (GC) in licorice roots and traditional Chinese medicines. A GC standard and the extracts of licorice roots and traditional Chinese medicines were applied to a polyethersulfone (PES) membrane and were developed by acetonitrile/water/formic acid (45:55:2, by volume), then treated with a NaIO4 solution followed by bovine serum albumin (BSA), resulting in a GC-BSA conjugate on a PES membrane. Anti-GC monoclonal antibody was bound and then a second antibody labeled with peroxidase directed against the first antibody. Finally a substrate reacted with the enzyme and gave staining. The stained membrane was scanned and coloring spots were analyzed quantitatively using graphic analysis by NIH Image software, indicating at least 0.5 microg of GC was clearly detectable. GC can be analyzed quantitatively between 1.0 and 8.0 microg.

Chromatography, High Pressure Liquid↗
PubMed1995

Evaluation of a total hematology analysis system (Sysmex HS-430). Benefits for large laboratories by reducing manual work load and optimizing screening efficacy for pathologic samples.

In this study, the authors evaluated a closed tube total hematology analysis system, Sysmex HS-430 (HS), which consists of two automated hematology analyzers, Sysmex NE-8000, the reticulocyte analyzer, Sysmex R-3000, and a slide preparation unit integrated in an automated sample transport system (TOA Medical Electronics, Kobe, Japan). The suitability of the system was compared with a conventional hematology system (CS) consisting of two single standing Coulter STKS analyzers (Hialeah, FL), one automated reticulocyte counter Sysmex R-1000, and the manual blood smear preparation. Evaluation was performed following the concept suggested by the Austrian-German societies for Clinical Chemistry and Laboratory Medicine that includes the evaluation of personnel supply. Eight consecutive series with a total of 4,896 samples were analyzed on both systems. Evaluation revealed that the analysis time per series was 238 minutes on the HS-430 and 359 minutes on the CS. The mean analyzer down times because of technical reasons were 36 minutes on the HS and 32 minutes on the CS. The down time because of "nontechnical" reasons was 31 minutes on the HS-430, but 173 minutes on the CS, which was mainly because of discontinuous sample loading of analyzers of the CS. The average direct technical time effort for complete blood cell count (CBC) analyses, reticulocyte counts, and blood smear preparations per series was 23 minutes on the HS and 245 minutes on the CS. In summary, these data show that an automated system like the HS-430 saves 222 minutes of manual activities arising in a large routine hematology laboratory with a mean throughout of 612 samples per day. Furthermore, the system improves intralaboratory turnaround times, avoids human errors by automated sample identification, and guarantees more safety for laboratory staff by minimizing the contact with potential biohazards.

Blood Cell Count↗
PubMed1989

A dietary and risk factor questionnaire and analysis system for personal computers.

The authors report the adaptation of a dietary and risk factor questionnaire and analysis system for use with IBM (or compatible) personal computers. This system includes a flexible computer-assisted interview program which may be modified to suit investigator needs while preserving a standard output format. It also includes a nutrient analysis program for calculation of usual dietary intake. Each of these two major components has its own set of utilities and options, so that investigators may tailor the system to particular research areas. The nature and capabilities of the two main programs are described, as well as the development of the underlying system and the general flow of data in the system.

Data Collection↗
PubMed2004

Tear film stability analysis system: introducing a new application for videokeratography.

PURPOSE: To review our previous studies regarding the development of a tear stability analysis system (TSAS) using videokeratography and the clinical application of TSAS for evaluation of tear film stability in patients subject to laser in situ keratomileusis (LASIK). METHODS: New software, namely TSAS, was developed for the videokeratography system TMS-2N (topographic modeling system). TSAS automatically captures consecutive corneal surface images every second for 10 seconds. Corneal topographs were analyzed for tear breakup time (TMS-BUT) and tear breakup area (TMS-BUA, the ratio of breakup area to entire color-code area). First, we recruited volunteers to test the sensitivity and specificity of this new system in comparison with the routine method for tear stability analysis, tear film breakup time evaluation by slit-lamp microscope (SLE-BUT), with fluorescence staining. Second, we investigated the practicability of TSAS in dynamic evaluation of tear film stability before and after LASIK. RESULTS: TMS-BUT had a positive correlation with SLE-BUT, whereas TMS-BUA showed a negative correlation. Although they showed similar rates of specificity as SLE-BUT, the sensitivity rates of TMS-BUT and TMS-BUA were 97.5% and 95%, respectively, significantly higher than that of SLE-BUT (75%). The study on patients subject to LASIK showed that tear film stability significantly decreased during the early time period following LASIK and resolved at 6 months after surgery. Eyes that had abnormal TSAS evaluation tended to have higher risk of developing superficial punctuate keratitis and dry eye symptoms after LASIK, and their responses to treatment were slow. CONCLUSIONS: TSAS is a noninvasive and objective method with higher sensitivity for tear film stability analysis than SLE-BUT.

Adolescent↗
PubMed1982

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↗
PubMedDate not supplied

A macro-ergonomic work system analysis of the diagnostic testing process in an outpatient health care facility for process improvement and patient safety.

The diagnosis of illness is important for quality patient care and patient safety and is greatly aided by diagnostic testing. For diagnostic tests, such as pathology and radiology, to positively impact patient care, the tests must be processed and the physician and patient must be notified of the results in a timely fashion. There are many steps in the diagnostic testing process, from ordering to result dissemination, where the process can break down and therefore delay patient care and reduce patient safety. This study was carried out to examine the diagnostic testing process (i.e. from ordering to result notification) and used a macro-ergonomic work system analysis to uncover system design flaws that contributed to delayed physician and patient notification of results. The study was carried out in a large urban outpatient health-care facility made up of 30 outpatient clinics. Results indicated a number of variances that contributed to delays, the majority of which occurred across the boundaries of different systems and were related to poor or absent feedback structures. Recommendations for improvements are discussed.

Diagnostic Errors↗
PubMed1991

Determinations of lactate and lactate dehydrogenase activity in serum with the flow injection analysis system involving immobilized enzyme column and chemiluminescence.

The methods for the highly sensitive flow injection analysis of lactate and lactate dehydrogenase (LDH) activity in serum using immobilized enzymes in column form and chemiluminescence detection which does not require a blank correction are described. The methods were based on the determination of chemiluminescence formed by the reaction of a luminol-ferricyanide mixture with hydrogen peroxide. This hydrogen peroxide was produced by the lactate oxidase (LOD) reaction from lactate, which was in serum or was produced by the action of LDH in serum. The action of LDH in a flow injection analysis system was performed for 2 min in an incubation coil placed parallel to the substrate-buffer line between the LOD column and the LOD/catalase column. Endogenous lactate in serum was removed by an immobilized LOD/catalase column prior to the action of LDH. The present method gave perfect linearity of the data up to 5.6 mmol/liter for lactate and 1840 IU/liter for LDH activity with satisfactory precision, reproducibility, and accurate reaction recoveries. The results from the lactate and LDH activity correlated satisfactorily with those obtained by other well-established methods.

Autoanalysis↗
PubMedDate not supplied

Characteristics of normal corneal topography using the EyeSys corneal analysis system.

PURPOSE: To study the parameters of corneal topography of normal eyes using the Corneal Analysis System (CAS, EyeSys Technologies) to determine the types and frequency of patterns and parameters. SETTING: University of Illinois Eye Center, Chicago, Illinois, USA. METHODS: Three independent, masked judges, using a forced-choice paradigm, classified corneal topography patterns into six categories on one randomly selected, normal eye of 100 persons who did not wear contact lenses. The patterns were defined by using the midpoint dioptric bin and a 0.50 diopter (D) steeper bin. RESULTS: The pattern frequency using the mid-dioptric bin was teardrop (6%), amorphous (11%), round (11%), symmetric bow tie (17%), asymmetric bow tie (1 %), kidney (22%), and oval (32%). Mean refractive and keratometric cylinders, respectively, were teardrop (0.13 and 0.15 D), amorphous (0.15 and 0.49 D), round (0.18 and 0.56 D), oval (0.21 and 0.56 D), kidney (0.51 and 0.72 D), and bow tie (1.18 and 1.82 D). Pattern frequency using the 0.50 D steeper bin was round (2%), oval (5%), teardrop (6%), kidney (15%), amorphous (17%), asymmetric bow tie (17%), and symmetric bow tie (37%). Mean refractive and keratometric cylinders, respectively, were round (0.13 and 0.32 D), amorphous (0.25 and 0.38 D), kidney (0.11 and 0.42 D), oval (0.40 and 0.59 D), teardrop (0.08 and 0.75 D), and bow tie (0.65 and 1.09 D). Mean flat and steep contours were 41.76 D (95% confidence interval [CI], 38.68 to 44.84 D) and 44.15 D (95% CI, 41.00 to 47.31 D), respectively. Mean contour range was 2.40 D (95% CI, 0.61 to 4.17 D). CONCLUSION: The data suggest that for 95% of normal corneas, corneal contours will be steeper than 38.50 D, flatter than 47.50 D, and have a contour range less than 4.25 D when using the EyeSys CAS.

Adolescent↗
PubMed2003

A real-time and dynamic biological information retrieval and analysis system (BIRAS).

The aim of this study is to design a biological information retrieval and analysis system (BIRAS) based on the Internet. Using the specific network protocol, BIRAS system could send and receive information from the Entrez search and retrieval system maintained by National Center for Biotechnology Information (NCBI) in USA. The literatures, nucleotide sequence, protein sequences, and other resources according to the user-defined term could then be retrieved and sent to the user by pop up message or by E-mail informing automatically using BIRAS system. All the information retrieving and analyzing processes are done in real-time. As a robust system for intelligently and dynamically retrieving and analyzing on the user-defined information, it is believed that BIRAS would be extensively used to retrieve specific information from large amount of biological databases in now days. The program is available on request from the corresponding author.

Animals↗
PubMed1998

Determination of SO(2) in Wines Using a Flow Injection Analysis System with Potentiometric Detection.

This paper describes the development and application of a flow injection analysis system manifold comprising a gas diffusion unit and a potentiometric detector to the determination of free and total SO(2) in white and red wines. A homogeneous crystalline iodide double-membrane tubular electrode was used as detector. SO(2) determination based on the Ripper method was carried out by dosing the iodide formed in the oxidation of SO(2) with iodine, followed by the separation of the formed compound through a diffusion Teflon membrane. The results obtained from the analyses of free and total SO(2) in 30 wine samples showed good agreement between the proposed method and the rapid assay method recommended by the UE and OIV. The relative error deviations of the results obtained by both methods were <6%. This procedure is suitable for samples with approximately 3.2-180 mg L(-)(1) SO(2), performing determinations of 75-100 samples h(-)(1).

Journal Article↗