PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Computer Terminals”

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 181 records · Page 10Linked to original sources
PubMed1976

[Data processing system for laboratory and hemodynamic heart catheterization measurements].

In cooperation with the Department of Electronic Data Processing Systems we have developed a data processing unit for the analysis of hemodynamic data at the Department of Internal Medicine I. The aim was to design a computer-system for the daily routine in heart-catheterizations as well as for the solution of scientific problems during hemodynamic studies. In the on-line-mode besides the ECG up to four pressures can be analysed simultaneously. Analog and digital tapes can also be processed off-line on demand. The concept of the whole system and the individual steps of computer-handling are adjusted to the problems of data-analysis in praxis from the viewpoint of the examining cardiologist. Since the system is interactive after each measurement and each given command the computer-results are displayed on the video-scope. Because of the modular structure of the program new medical criteria can easily be implemented at any time. Since the computer-system is not effectively used with only one cath-lab other units possibly of different hard-ware configuration can be connected simultaneously to the computer. Each cath-lab shares 16 K out of the total 32 K core-memory. The results are displayed graphically and alpha-numerically on video-scope, x-y-plotter and line printer. The sampling-rate for fluid-filled catheters is 200 Hz and for catheter-tip-manometers 400 Hz. Smothing and differentiation-procedures are adapted to the respective catheter-material. The computer-program calibrates the different pressure amplifiers automatically. After defining the catheter-position the pressure-signals are sampled for 10 s and immediately afterwards analyzed by the computer. The ECG and the corresponding pressure-curves are displayed on the video-scope. The automatically selected representative beat as well as each of the identified and numerated other beats of the sampling-phase can be displayed selectively together with its numerical results. The computer marks the positions within the pressure-curves, where the individual measurements were taken. Besides the systolic and diastolic pressures in valvular stenosis the maximal and mean systolic or diastolic gradients, ejection- or filling-period, valve-flow and valve-area are calculated autonomously. The calculation of cardiac-output, different volume-indices and stroke-work-index are based on Fick-method, thermo- or indicator-dilution technique. The contractility-parameters max dp/dt, t-max dp/dt, max dp/dt/DP, max dp/dt/P, VPM, V40, min dp/dt and the stiffness are computed for the left and on demand also for the right ventricle. Data of the patient and the operating-team, catheter-technique, complications and free comments are transmitted to the computer via terminal together with the actual time. The computer-system was drafted for permanent use. Therefore possible technical defects have been anticipated in the design of hard- and soft-ware. In cases of failure suitable steps allow the immediate restart of the system without loosing information...

Angiocardiography↗
PubMed1990

Linking and integrating computers for maternity care.

Functionally separate computer systems have been developed for many different areas relevant to maternity care, e.g. maternity data collection, pathology and imaging reports, staff rostering, personnel, accounting, audit, primary care etc. Using land lines, modems and network gateways, many such quite distinct computer programs or databases can be made accessible from a single terminal. If computer systems are to attain their full potential for the improvement of the maternity care, there will be a need not only for terminal emulation but also for more complex integration. Major obstacles must be overcome before such integration is widely achieved. Technical and conceptual progress towards overcoming these problems is discussed, with particular reference to the OSI (open systems interconnection) initiative, to the Read clinical classification and to the MUMMIES CBS (Common Basic Specification) Maternity Care Project. The issue of confidentiality is also briefly explored.

Confidentiality↗
PubMed1993

An overview of human-computer interaction.

This article presents an overview of the field of human-computer interaction. This branch of computer science concerns the design, implementation and analysis of interactive computer systems. We show that this field is multidisciplinary in essence, involving social scientists as well as computer scientists, experts of application domains, graphics designers, etc. Once the fundamental aspects of human-computer interaction are presented, we take a practical approach in order to introduce the methods, tools and techniques that are available today for the design and implementation of interactive computer systems. Finally, we present the main directions of research in this domain.

Computer Simulation↗
PubMed1993

Digitally reconstructed fluoroscopy and other interactive volume visualizations in 3-D treatment planning.

PURPOSE: Add radiographic context to the beam's-eye-view used in 3-dimensional treatment planning. Improve methods for interactive visualization of anatomy and dose distributions. METHODS AND MATERIALS: Most 3-dimensional treatment planning systems feature a beam's-eye view that includes only graphical representations of patient anatomy. With input devices such as a mouse or trackball, the user interactively shapes the treatment field using the graphical models to provide geometric information. Radiographic context provides additional geometric information important for determining field shape. We have implemented digitally reconstructed fluoroscopy in the beam's-eye view by increasing the efficiency for computing digitally reconstructed radiographs. In addition we have improved algorithms for real-time surface and volume rendering for anatomy and doses using an experimental graphics supercomputer. RESULTS: Without radiographic context in the beam's-eye-view, field shapes were sometimes changed after simulation or portal images were obtained. Digitally reconstructed fluoroscopy has essentially eliminated these changes. Higher quality interactive three-dimensional displays improve the comprehension, confidence and efficiency of the user. Our improvements have already been implemented on one model of a new generation of commercial graphics workstations. CONCLUSION: Addition of radiographic context to the beam's-eye-view is recommended. Incorporation of higher quality interactive graphics is rapidly becoming practical and is encouraged.

Computer Simulation↗
PubMedDate not supplied

Interactive multiplanar reformation of conventional two-dimensional MR images.

In this report, we describe a new application for three-dimensional computer image processing that can provide for improved depiction of anatomical structures on routine nonvolumetric magnetic resonance (MR) examinations. The technique can be applied to standard two-dimensional MR images of the brain, spine, musculoskeletal system, and body including those obtained with relatively thick slices and with an intersection gap. This report demonstrates use of the reformation technique to establish retrospectively the symmetry in bilateral structures that were displayed out of alignment due to suboptimal patient positioning or patient motion during image acquisition and to improve the depiction of anatomical structures that were oriented out of the plane of original image acquisition. This method can be performed interactively in near real time, requires no increase in patient examination time, and has potential application throughout the body.

Artifacts↗
PubMed1971

A neuron model with spatially distributed synaptic input.

I have assembled a neuron model simulating contiguous patches of nerve cell membrane. With this model I have examined the functional significance of different spatial and temporal distributions of synaptic inputs. The model consists of two terminal electronic analogue circuits with inputs controlled by a LINC computer. One terminal represents the inside of a membrane patch, the other represents the outside. Two circuit designs are used: one simulates spike-generating regions of the neuron, the other simulates subthreshold activity in inexcitable regions. To simulate a neuron, patches are assembled in various spatial arrangements by suitable connection to the "intracellular" nodes. Thus the relation of neuron geometry to aspects of spatiotemporal summation of synaptic inputs can be investigated readily. Performance of the model is assessed by comparison with results from microelectrode studies in the cochlear nucleus of the cat. In particular, the peristimulus time (PST) histogram and averaged membrane potential are used for quantitative comparison. The model suggests that the geometry of the neuron's receptive surface can account for a wide variety of physiologically observed behavior, particularly in response to dynamic stimuli.

Action Potentials↗
PubMed1976

Computerised assessment of cardiac pacemaker performance.

The design and use of a PDP 11/40 based automated on-line cardiac pacemaker assessment system is described. One program has been developed for testing pacemakers on the bench and another for implanted pacemaker tests. Either fixed rate or demand pacemakers can be tested. The on-line system is easy and fast to use and is also highly accurate. Parameters extracted are pulse width, rate and pulse energy. In addition, a graphical representation of the patient's ECG and the pacemaker pulse is obtained on a computer graphics terminal.

Computers↗
PubMedDate not supplied

Evaluation of video gray-scale display.

Setting up and maintaining video display monitors properly will help to reduce display variation and improve overall presentation of the radiological image. Display monitor gray-scale characteristics were examined using the SMPTE test pattern. This test pattern may be used as a standard for adjusting brightness and contrast. The controls should be adjusted to display the full dynamic range so that the 5% and 95% signal levels in the pattern are visible. Measured luminance on a laboratory workstation used for radiological perceptual experiments, and on the Siemens CT gray-scale monitor was determined to range from 0.17 to 76.0 nit, and 0.17 to 24.66 nit, respectively. These were compared with the range of approximately 17 to 514 nit for a typical film-viewbox combination. Characteristic curves were determined for both monitors, and CRT gammas were 3.34 and 2.48 for the perceptual workstation and CT console, respectively. The display gamma was determined from fitting luminance data to a log-log plot of luminance versus input gray level. The usefulness of the SMPTE test pattern for visual presentation as well as photometric measurement is demonstrated.

Computer Terminals↗