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PubMed1995

"Informed consent" interactive videodisc for patients having a colonoscopy, a polypectomy, and an endoscopy.

These "informed consent" interactive videodisc programs use both graphic and live action sequences to describe in detail the diagnostic procedures of Endoscopy, Colonoscopy, and Polypectomy. Both benefits and possible risks are listed and described. After each sequence, the patient is asked whether the explanation is understood and/or whether the patient would like to discuss the procedure in more detail with a physician. The programs were designed for use with marginally literate patients and require no reading ability. Both programs are also ideal for general patient education.

Analog-Digital Conversion↗
PubMed1995

The design and application of microcomputer human body information balance diagnosis and treatment instrument.

In Chinese medical theory, it is thought that if the "Yin and Yang balance, person will be healthy." Chinese medicine studies the human body as a whole which has specific functions. Chinese medical main and collateral channels are confirmed by experts at home and abroad as Ra kind of internal structure system that really exists.S It has been confirmed that imbalances caused by almost all diseases can be reflected in main and collateral channels system; the channels can adjust and control the physiological function and pathological expression of human body's viscera and bowels. The adjustment for the human body can be accomplished through reaction points of body surface and main and collateral channels. Since 1989, the studies of other countries have confirmed that the human body is a combined control system that owns various adjustment mechanism. The adjustment and control for human body state can be accomplished through biological information. Based on the above theory, the authors of this paper designed the instrument that can make diagnosis and treatment automatic. Biological information sensors are attached to the points of main and collateral channels, and they sense the signals of disease of the human body. Through an A/D converter, the signal is input into a microcomputer. The CPU makes a comprehensive analysis and diagnosis according to the program and the signs and amplitude of signal deviation values detected from the left and right main and collateral channels points; it gives relevant information treatment prescription. After D/A converting, the information treatment wave generator is activated. The composed information wave treats the human body through the main and collateral channels points, and the changes after treatment are fed back to the computer through biological information sensors to amend the treatment prescription and generate the new information treatment combination wave, which is again fed back. At last, the body system will reach stability and balance through many circulations. Through 300 cases of clinical practice, the total effective rate for 22 kinds of disease such as stomach ache, coronary heart disease, and Meniere's disease reaches 90.0%. Among these, the marked effect accounts for 7.3%; the improvement accounts for 82.7%. After processing by statistics, it shows that the instrument has a marked curative effect. In theory, the instrument has the functions of diagnosis, treatment, health care, adjustment of body immunity, prevention of cancer, the curing of nerve functional diseases and some nerve and spirit diseases, etc. It is estimated that the instrument will be used in more fields; it has good application prospects, and will become a new therapy in home medical care.

Analog-Digital Conversion↗
PubMed1996

Image acquisition. Sites, technologies, and approaches.

This article examines the current and future methodologies for image capture. Data conversion devices and systems, radiographic techniques of ionizing and nonionizing radiation, passive imaging, and digital image data requirements are explored. The author also discusses the problem of how to connect acquisition devices to PACS.

Analog-Digital Conversion↗
PubMed1995

[The objective and perspective of recording electrical activity from the central nervous system].

In 1929 Hans Bergr successfully recorded electrical activity from the human brain using surface scalp electrodes. Since, the EEG has brought significant contributions to the fields of clinical neurology and neurophysiology. As a clinical diagnostic tool, the EEG has provided information for functional as well anatomical (structural) brain disturbances. As a functional diagnosis, the EEG is far superior to other functional tests such as PET, SPECT or functional MRI because of its excellent temporal resolution representing moment to moment changes in the level of consciousness. However, the progress has been hampered due to difficulty in quantifying EEG data because of its extreme dynamics and variability, which perhaps reflects yet unknown brain functions. This difficulty will be overcome by improved quantification methods and statistical measures using various computer applications including topographic mapping, power spectrum analysis, covariance, correlation or coherence function. Because of its poor spacial resolution, the EEG has relinquished its place to CT and MRI scans as an anatomical diagnostic tool. The surface recorded electrical activity is greatly attenuated and distorted by the time it reaches to the scalp. This is due to the inhomogeneous tissues (CSF, dura, skull, scalp) that intervene between the recording electrodes and cortical surface. Because the human body or head consists of electroconductive media of various geometries, current distortion, far-field potentials or paradoxical lateralizations further complicate the interpretation of EEG in postulating the location of anatomical generator sources from surface recorded EEG. Advanced computer technology is in progress to quantify the EEG data by taking into account the factors of conductivity, geometry shape and individual head size. This will improve the accuracy of localizing current generator sources in relationship to brain anatomy. By solving these problems in a methodical fashion, EEG will become the revelation for understanding the functional anatomy of brain and will step closer to Berger's dream, "EEG is a window of human mental activity".

Action Potentials↗
PubMedDate not supplied

[The use of a Russian software-hardware package for the quantitative analysis of coronary angiograms].

The software and hardware complex developed by the Cardiology Research Center, Russian Academy of Medical Sciences, jointly with the Technomash Research Production Association on the basis of a IBM 386DX personal computer equipped with a VS-100 video controller and a DS P31 VS signal processor board. Testing has indicated that it provides a qualitative image and a quantitative analysis both of phantoms and real images of coronarograms, but more accurately in the analysis of the image obtained from a film projector. Valid results are yielded when lenses more than 1 mm in diameter are used. Clinical tests have shown that the software and hardware complex may yield a rather qualitative image and calculate the required diameter of a vessel, virtually without prolonging the time of intervention, which is particularly important while making intervention procedures and implementing research programmes.

Analog-Digital Conversion↗
PubMed1986

Computers in biology: the future is today.

Which are the applications of microcomputers in biology today? Some areas where the work with microcomputers is becoming increasingly important are considered: laboratory applications, event simulation and word processing. Almost all laboratory computer applications can be described as one of the following functions: 1. control of experiments, including timing and synchronizing external voltages; 2. data acquisition, usually through digital conversion of analog electrical signals; 3. data storage and, 4. data analysis. Event simulation is considered both as a research tool and as an important element in the educational area. Word processing and the automatic creation of literature references lists is considered as an ignored role of the microcomputers in the laboratory field. What about the influence of biology in computer technology? As specialized magazines say, many laboratories of biotechnologist are working hard to build a molecular computer. That is, an artificially designed ultramicroscopic machine built of proteins, nucleic acids, metals and non-metals in a planned arrangement. And this is not the end. The latest application able to expand our horizon in the biological field may be starting to be used at this moment.

Analog-Digital Conversion↗
PubMed1986

Automation of data acquisition and of experiment control: application to the study of sleep-wake cycles and behavioral paradigms.

The low cost of microcomputers allows them to be dedicated full time to data acquisition and analysis of experimental paradigms. The usual interfaces required for such interaction with the experiment are briefly explained, namely, analog-to-digital converters, input-output control lines and real time clocks. Some basic concepts on the use of microcomputers for the automation of data acquisition and control are summarized, including the characterization of waveshapes, the structure of data storage and on-line data reduction. Off-line, the matrices generated by the data acquisition program become the input for ad-hoc processing programs. Precision, flexibility and fluidity of analysis are outstanding advantages of computer controlled setups. A system for automation of sleep studies and a system for automation of scheduled-controlled behavior are presented as working examples.

Activity Cycles↗
PubMed1986

[Digital image processing: fundamental techniques and applications in biological research].

Digital image processing represents a relatively new but very dynamic domain. Its importance is still growing due to the rapid development in related computer equipment. In this paper basics concepts are introduced and a survey of problems and methods is presented. Starting with techniques used for the capture of data, it continues with techniques applied to coding new data, image enhancement and pattern recognition. Special attention is given to pattern recognition techniques which provide the basics for classification of data according to established criteria. Finally, two applications are presented; the reconstruction of 3-D volumes from serial cutting and a survey of chlorophyll concentration on Lake Aculeo using remote images obtained by the LANDSAT satellite.

Analog-Digital Conversion↗
PubMedDate not supplied

[The spatial organization of the EEG and individual psychological characteristics].

The influence of cognitive styles (analytic versus synthetic style, rigid versus flexible cognitive control, impulsivity versus reflexivity, field-dependence versus independence) on the information brain processes was estimated by means of analysis of spatial organization of cortical electrical activity (48 derivations) in 40 right-handed subjects (aged from 18 to 40) during their realization of verbal and non-verbal tasks using successive and simultaneous processing modes. Modulation of the "cognitive axis" (activity of the left anterior and right posterior cortical areas) was revealed connected with the factor of task subjective difficulty, especially in case of simultaneous processing mode. The combination of the synthetic cognitive style and flexibility of the cognitive control may be thought of as being the most favourable for the activation of the "cognitive axis" and utilization of the left- and right-hemispheric information processing, especially in non-standard situations.

Adolescent↗
PubMedDate not supplied

[Devices for measuring the temperature of laboratory animals].

Three devices for measuring body temperature in small laboratory animals were designed: analogous thermometer, temperature-to-frequency converter for digital temperature assessment by means of a universal frequency meter and a portable digital thermometer providing temperature measurement accurate to 0.1 degree C. The devices were tested in experiments on laboratory rats and mice and proved to be highly reliable in long-term recording of parameters.

Analog-Digital Conversion↗
PubMed1996

[Histo-morphometry of bone mass and cellularity using image analysis: characterization of infiltration patterns in CLL].

PURPOSE: The aim of this study was to investigate a possible influence of lymphocytic infiltration in Chronic Lymphocytic Leukemia (CLL) on bone mass, according to the infiltration patterns. MATERIAL AND METHODS: We have studied histological preparations from decalcified and paraffin included bone biopsies and used a histomorphometric study through a mixed (interactive-automatic) image analysis, in order to quantify bone trabecular (BT/TV) and cellular volume (CV). Preparations were visualized via a 2.5 objective; a video camera was adapted and connected to a computer with analogical-digital converter incorporated. After the image was captured, a binarization was made by trabecular and medullary spaces segmentation; automatically, we calculated trabecular area (TA) and cellular area (CA). Expressions indicated above were used to calculate BV/TV and CV, expressed in percentage: BV/TV (%) = [TA/(TA + CA)] x 100, and CV (%) = [CA/(TA + CA)] x 100. RESULTS: 92 normal biopsies and 79 CLL biopsies were studied (Nodular 12, Diffuse 22, Interstitial 23, Mixed 22). BT/TV in normal subjects age over 45, was 18.40%; it was lower in CLL subjects, 17.25%. CV was 33.62% in normal cases and significantly higher in CLL with 42.95%. According to the infiltration patterns, Nodular pattern showed similar value to normal biopsies, versus Diffuse pattern with BT/TV of 16.19% and CV of 51.49%. Significantly, a high CV value was accompanied of a low B/TV value, in normal and CLL subjects. CONCLUSIONS: We analyzed histomorphometrically trabecular volume as expression of bone mass in undecalcified biopsies. CLL infiltration tended to show a lower trabecular volume. Diffuse pattern presented the higher cellular infiltration and bone mass destruction.

Aged↗
PubMed1997

Vibration transmission across the temporomandibular joint.

A non-invasive method of assessing the status of the temporomandibular joint is presented. The method involves placing a computer-controlled vibrator against a lower incisor, and microphones over the temporal bones. The amplitude of the signal transmitted is shown to be a function of the input frequency, the position of the mandible and the loading on the joint.

Acoustics↗