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At least 721 records · Page 40Linked to original sources
PubMed2002

Development of a digital signal processor-based new 12-lead synchronization electrocardiogram automatic analysis system.

This paper presents a digital signal processor (DSP)-based new multichannel electrocardiogram (ECG) system for 12-lead synchronization ECG automatic analysis in real-time with high sampling rate at 1000 Hz and 12-bits precision. Using the hardware structure of double-CPU based on Microprocessor (MPU) 89C55 and DSP TMS320F206 combines the powerful control ability of MPU with DSPs fast computation ability. Fully utilizing the double-CPUs resource, the system can distribute the reasonable CPU-time for the real-time tasks of multichannel synchronization ECG sampling, digital filter, data storing, waveform automatic analysis and print at high sampling rate. The digital ECG system has the advantages of simple structure, sampling with high speed and precision, powerful real-time processing ability and good quality. The paper discusses the system's principle and the skilful hardware design, also gives the ECG processing using the fast simple integer-coefficient filter method and the automatic calculation algorithms of the ECG parameters such as heart rate, P-R interval, Q-T interval and deflexion angle of ECG-axis etc. The system had been successfully tested and used in the ECG automatic analysis instrument.

Automation↗
PubMed1987

Emergency bypass system: analysis of gas transfer.

A portable emergency bypass system using a membrane oxygenator device (CPS) was evaluated. The ability of the CPS to supply the oxygen transfer needs of five anesthetized dogs consistently over six hours and the system's effects on hemoglobin concentration, platelet count, and degree of hemolysis were assessed. The animals maintained spontaneous heart beats, pump flows averaged 100 ml/kg/min; mean arterial pressures were maintained at from 114 to 144 mm Hg. Immediate dilution of hemoglobin and platelet levels occurred in the first 30 minutes. Further hemodilution was limited during the first two hours, although three of the animals required transfusions during the six-hour period to maintain their hematocrits. Plasma free hemoglobin did not significantly increase during the six hours. Baseline oxygen consumption data obtained in three animals ranged from 44.5 to 96 (ml oxygen/min/m2). Oxygen and carbon dioxide transfer measurements during the first hour of bypass were not significantly different from measurements during the last hour of perfusion. The study suggests that optimal use of the CPS could supply much if not all of a patient's basal oxygen transfer requirements for at least six hours.

Animals↗
PubMed1986

[A health system. Analysis and proposals].

The author examines the health system of Brazil and points out the aspects that need to be changed for attainment of the World Health Organization's goal of health for all by the year 2000. To solve these problems the author proposes, i.a., full integration of the resources and coordination of the activities of the Ministry of Health and the National Social Security Institute of Medical Care with a view to active preventive coverage for educating the population, controlling the vectors of disease, improving the environment, vaccinating, monitoring expectant mothers and infant growth, etc. In addition, he advocates determining the proportion of the contribution to social security to be set aside for health purposes at a specific percentage and removing the cap on that part of the contribution so that the costs of medical care will be more equitably distributed.

Brazil↗
PubMed1994

MRI scanner variability studies using a semi-automated analysis system.

Due to the unique design of the Parallel Rod Test Object (PRoTO) and the associated semi-automated analysis program, it was necessary to test it extensively for precision and accuracy, and preliminarily for utility, before its distribution for wider use in MRI system quality control (QC). The test object and analysis program measured the desired quantities reproducibly and they accurately measured predicted changes from intentionally adjusted imaging system parameters, yielding sensitivity of the various test measures to deviation in the system operating parameters. From a single scan of the most recent revision of the test object, multiple quantitative quality control measures were obtained throughout the scanning volume on two MR imaging systems over periods of six and twelve months, respectively. From these and earlier trials, an initial indication was obtained of which performance measures are worth monitoring for QC. This experience suggests that signal-to-noise ratio (SNR) and distortion (including display scale) should be monitored but not necessarily the resolution. The latter was only found to alter at the same time or later than other parameters such as SNR had changed. Slice thickness was found to vary on some units and this measure was also used in normalizing the SNR by voxel volume. SNR, distortion, and resolution measurements using field-echo sequences were less stable than those using spin-echo sequences. Use of this QC program to test a wide variety of image quality measures allowed timely assessment of the long-term variability of the units tested. Long-term variability may become among the most important measures for comparison of system performance and maintenance.(ABSTRACT TRUNCATED AT 250 WORDS)

Artifacts↗
PubMed1986

The use of a system analysis approach to electrodiagnostic (ERG and VEP) assessment.

To evaluate the integrity of a biological system and its constituent functional units, a systematic study of input-output relations adopted from engineering has proven appropriate. With such an approach, sequential analysis can be implemented to probe the various parameter extractions along, for example, the visual system. The a priori assumption in this approach is that the visual world is processed along functionally separate pathways yielding distinct percepts such as contrast and motion. This so-called channel approach has proven useful not only to basic vision research but also for clinical application. The present overview shows that on the basis of the ERG or VEP, a type of functional anatomy can be performed with the biological system of interest remaining intact. Finally, it will be demonstrated that electrophysiological output parameters of the visual system can also serve as a non-invasive entry to investigate general systemic disorders.

Adult↗
PubMed1975

Refinements in the automated fluorometric histamine analysis system.

The automated continuous flow system for the extraction and fluorometric analysis of histamine has been further improved. Samples with or without protein can be analyzed. The use of a single pump, added nitrogen, and lower concentration of o-phthalaldehyde increase the sensitivity by 5-10 fold and allow the analysis of samples at the rate of 30 per hour. Samples which are less than 0.5 ml in volume and contain 0.1 to 10 ng/ml histamine can routinely be analyzed. The sensitivity of the system is now 0.05 ng and compares favorably with isotopic techniques.

Aldehydes↗
PubMed1993

Systems analysis of an occupational health department: recommendations to increase effectiveness.

The author analyzes the occupational health department of an urban health maintenance organization using systems theory. The framework for the analysis includes the environment, inputs, throughputs, outputs, evaluation, and forces of entropy and negentropy, as well as stresses and strains. Recommendations to increase the effectiveness of the department are based on the analysis. Any occupational health department could benefit from a similar analysis.

Efficiency↗
PubMed2005

Tanita foot-to-foot bioelectrical impedance analysis system validated in older adults.

Simple, accurate, and noninvasive methods for assessing body composition are needed in many clinical, community, and research settings. The foot-to-foot bioelectrical impedance analysis (BIA) system may be one method of addressing those needs. The objective of this study was to determine the validity of a foot-to-foot BIA system for body-composition assessment of older adults. Subjects 55 years of age or older without functional limitations or cognitive impairments (N=50) were measured using both the Tanita foot-to-foot system (Tanita Corporation of America, Inc, Arlington Heights, IL) and traditional hand-to-foot BIA. The correlation for percent body fat measurements between the Tanita and traditional BIA was r=0.84 (P<.001). Percent body fat estimates from both BIA measures were significantly correlated with waist circumference, body mass index, and age (all P<.01). The Tanita BIA system provides a valid measure of percent body fat in older adults, and could be a convenient and practical approach for assessment in public health settings.

Adipose Tissue↗