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At least 37 records · Page 2Linked to original sources
PubMed1976

SCANCANS--an interactive scanning cell analysis system.

This paper describes a computerized, general-purpose, interactive, scanning cell-analysis system developed at the Department of Clinical Cytology of the University Hospital in Uppsala. The system uses a Leitz MPV II scanning photometer, a PDP-8 computer with 24 k of core memory and a Tektronix 4010 graphic display terminal. A command interpreter and overlay structure which makes it simple to add new capabilities to the system is described. Some examples of command strings and the kind of operations the system can perform are included. Finally, the experience gained from using the system and some plans for future extensions are discussed.

Autoanalysis↗
PubMed1979

Quantification of human sperm morphology and motility by means of semi-automatic image analysis systems.

Sperm morphology and motility are determined using a semi-automatic image analysis system under opto-manual control. The system consists of a microscope equipped with a drawing-tube, a digitizer-tablet, and a cursor interfaced to a small microcomputer. A light-emitting diode is mounted on the cursor, visible as a bright red pilot-light in the microscopic field. Sperm head and midpiece as well as the pathway of motile spermatozoa are traced with the cursor's red pilot light. The microcomputer calculates area, circumference, and length simultaneously. Motility and sperm density are determined altogether using microchamber technique. In a selected group of male subjects with normal, doubtful, and pathological semen analyses biometrical analyses of sperm morphology and motility were performed. Sperm morphology is best described by the variation of the head size and by the average midpiece width. Motility is best described by % motile spermatozoa and mean velocity determined 1 hour after semen collection. Biometrical semen analyses are superior to subjective evaluations regarding degree of information, objectivity, and reproducibility.

Cell Survival↗
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↗
PubMed1978

A microcomputer-based data acquisition and analysis system for CO2 rebreathing studies.

A real-time microcomputer-based data acquisition and analysis system has been developed to automate the measurement of the ventilatory response to CO2 by the rebreathing method. Previous systems acquire the data on-line and then analyze and display the results off-line. The system described here performs all processing on-line and displays experimental results in real-time. The results of 5 min of data acquisition are available for display only 1.5 sec after completion of the experiment. Immediate interpretation of the results of each experiment enable a series of related studies to be performed on the same patient in a short time period. The microcomputer is Digital Equipment Corporation's LSI-11, a low cost 16 bit machine with the basic instruction set of a PDP-11/40. The system has 16 kbytes of memory, a CRT for data display, and a paper tape reader for program loading. Due to the time constraints of real-time processing and the memory constraints of a small system, the software is written entirely in assembler language. The software includes routines for numeric and character input, line and graphical output, linear curve fitting, start of rise detection and floating point computations.

Carbon Dioxide↗
PubMedDate not supplied

An automated fluorescent excitation analysis system for medical applications.

The use of stable tracers assayed by x-ray fluorescent excitation analysis has proven advantageous over other stable or radioisotopic techniques in a number of clinical and investigative situations. An automated fluorescent excitation analysis system for medical application has developed. Its design parameters and performance are described.

Blood Volume Determination↗
PubMed1976

The cross sectional area of diaphragmatic muscle fibres in emphysema, measured by an automated image analysis system.

The cross-sectional area of diaphragmatic muscle fibres was measured using a Quantimet 720 image analysis system in 18 patients with emphysema and six control non-emphysematous patients. The technique proved to be an accurate method of measuring muscle fibre area and much more rapid than the previously described methods. The mean cross-sectional area of the muscle fibres in the emphysematous group was 1069-5 mum2 and this was significantly greater than the mean of the control group which was 851-0 mum2. In the emphysematous group nine patients who died from chronic airways obstruction had a larger mean muscle fibre area than the nine patients with non-fatal respiratory disease. The emphysematous patients showed a marked increase in the number of very large muscle fibres (2000-2200 mum2) in the diaphrahm and also an increased variation in size from fibre to fibre. The increase in muscle fibre size showed a positive correlation with ventricular weight but not with the amount of emphysema in the lungs. It would appear that although the excursion of the diaphragm is reduced in emphysema the muscle fibres do not atrophy but in fact undergo work hypertrophy. This is presumably due to the horizontal shortening of the muscle fibres, when the diaphragm is working at a poor mechanical advantage, because it cannot descend normally in emphysematous patients.

Adolescent↗
PubMed1976

Systems analysis of computerized EKG processing center.

A functional description of a computerized system for analysis of electrocardiograms (EKGs) is presented. Although it is recognized that the diagnostic accuracy of the program is the critical parameter in determining system acceptance, other system features such as quality control, turn around time and cost are shown to be of high importance. A digital simulation of alternative configurations for on-line data acquisition is presented. The simulation predicts the system throughout and wait times in different phases of a telephone EKG transmission for combinations of interfaces, telephone lines and acquisition procedures. These results should be helpful in selecting the appropriate configuration for each special situation.

Computers↗
PubMed1976

Systems analysis in nutrition and health planning: approximate model relating birth weight and age to risk of deficient growth.

This paper summarizes the initial phase of an effort to develop semiquantitative methods for nutrition and health planning. The general approach is to utilize the methods of systems analysis and operations research where appropriate, but the emphasis is on developing a simplified, approximate analysis that government planning groups could conveniently apply in evaluating various potential programs for attaining specific nutrition and health objectives, while satisfying certain constraints (e.g., budget, facilities, personnel). An essential element of the analysis is a model that provides an approximate description of malnutrition (inadequate growth, as indicated by weight for age) and mortality in terms of those variables that can be affected by intervention programs. We have concentrated initially on using the results of two INCAP longitudinal studies to develop models relating the incidence of malnutrition (second and third degree on the Gomez scale) to age and previous growth, including birth weight. The two studies cover rural Guatemalan communities with considerable variability in ethnic, socioeconomic, and ecological conditions. Because they are tentative, the resulting models are discussed only qualitatively and not quantitatively. The models may serve as baselines to estimate the consequences of potential programs aimed at different target groups, such as pregnant women and children whose weights at birth or thereafter fall below prescribed levels. The possible benefits of using models of this nature in nutrition and health planning are discussed.

Age Factors↗
PubMed1992

Development and distribution of the white blood cells within various structures of the human menstrual corpus luteum examined using an image analysis system.

PROBLEM: Emerging evidences suggest that immunoendocrine interactions play definitive roles during development and regression of the human menstrual corpus luteum (hmCL). We have studied the distribution of immune cells within individual structures of hmCL during various stages of its development. METHOD: Immunoperoxidase-stained ultra-thin frozen sections were evaluated using light microscopy fitted with an image analysis system. RESULTS: The results suggest that monocytes/macrophages and MHC class II positive cells are the most prominent immune cells within the hmCL throughout its whole lifespan. Both cell types are concentrated within the trabeculae. In addition, MHC class II positive cells are abundant also within the granulosa-luteal layer. T helper/inductor (Th/i) and T cytotoxic/suppressor (Tc/s) cells were detected only in minor amounts within the thecal trabeculae of mature tissue. CONCLUSIONS: Possible links between the occurrence and functional roles of the immune cells studied are discussed.

Antigens, CD↗
PubMed1979

"Blind focusing": an objective method for avoiding errors of focus at the television texture analysis system (TAS).

The amount of light energy a particle absorbs does not depend upon correct focus. The change in the path of light rays brought about by defocusing causes absorbing areas to be registered as areas of higher transmittance than when in focus. Already wellknown in photometry, this effect is put to use by the "blind focus" method at the television texture analysis system (TAS, Leitz). Some chromophores within the object to be measured are compared to a preset value of transmittance, for example T = 0.40. Only the area representing the structures as dense or denser than the preset density are registered. If the structures are out of focus the size of the registered area is too low, since by defocusing, structures to be measured become pale and diffuse, the correct focus corresponds to the largest area to a preset value of transmittance.

Amnion↗
PubMed1979

Morpho-functional principle of neuroendocrine system analysis.

A new approach to the analysis of the neuroendocrine system (NES) is suggested. It is based on the fact of structural and metabolic determination of any effect on cell and cell aggregates. The principle of a common communication channel in the NES is formulated and a possible method of its formalization is proposed.

Cell Membrane↗
PubMed1992

Systems analysis of a drug dependency service in London: St George's Hospital.

Elements of a systems approach to analysing service delivery are outlined. A specific example--St George's Hospital Addiction Behaviour Department--is detailed. Dynamics of the system--from the client's perspective and the workers viewpoint--demonstrate some of the ways in which emotional conflict surrounding the task is handled. The conclusions focus on what might constitute adaptive resolution of systems dilemmas as well as highlighting the public-health concerns relating to AIDS which, we argue, compromise the primary task of an addiction service at the present time.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Systems analysis of possible mechanisms of mammalian aging.

A comparison is made between how bacteria and men use their DNA to accomplish any major biological function. To make this comparison, a modified cybernetic analysis was used. This new type of cybernetic analysis makes a distinction between controlled and regulated systems and may permit an extension of cybernetics into new areas of biology. Prokaryotes have only regulated systems for all major functions, whereas eukaryotes can have both regulated and controlled systems. Several lines of reasoning, including the new cybernetic analysis, suggest that death, as opposed to aging, may be a regulated function in mammals. By analogy with other major regulated developmental functions in mammals, it is also suggested that the hypothalamic-pituitary axis may be the site for the regulation of the time of death. An example of how the pituitary might act on the DNA of peripheral cells to cause possible, severe loss of functional capacity is given by some recent experiments with RNA polymerase activity of liver nuclei from rats of different ages and with different endocrine states.

Aging↗
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↗