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At least 451 records · Page 25Linked to original sources
PubMed1990

[Rotational instability of the lumbar spine--a three-dimensional motion study using bi-plane X-ray analysis system].

The purpose of this study is to investigate the rotational instability of the lumbar spine using bi-plane X-ray analysis system and to clarify mechanical etiology of the lumbar instability. The following results were obtained. (1) The range of rotational motion was about 2 to 3 degrees at each motion segment in the normal lumbar spine. The rotational motion was significantly large in spondylolysis, spondylolisthesis, and degenerative spondylolisthesis. (2) The rotational instability and the flexion-extension instability correlated to each other in spondylolysis and spondylolisthesis. However, in degenerative spondylolisthesis, the rotational instability and the antero-posterior instability were correlated to each other. (3) Instantaneous axis of rotation (IAR) was located at the posterior part of the intervertebral disc in the normal L4 vertebra, and more posteriorly in the L5 vertebra, while the IAR was located anteriorly in spondylolysis, and posteriorly in degenerative spondylolisthesis. (4) When the trunk was twisted, the lumbar lordotic angle was generally decreased, and the lumbar spine showed scoliotic curvature convex to the twisted direction. The apex was located at the L4/5 intervertebral level. Highly significant increases in flexion motion associated with rotation were observed at the pathological levels of spondylolysis and degenerative spondylolisthesis.

Adult↗
PubMed1981

Macrophage adherence inhibition assay: measurements of adherent cells by the TV image analysis system Densitron.

A procedure is described to automate the cell counting step in the indirect macrophage adherence inhibition assay using the TV image analysis system Densitron. Comparison of the results of direct visual counting and of Densitron measurements of the adherent cells in the haemocytometer chamber indicates the qualification on principle of Densitron to substitute the time consuming and exerting visual counting procedure.

Animals↗
PubMed2005

Thermoplastic elastomer gels: an advanced substrate for microfluidic chemical analysis systems.

We demonstrate the use of thermoplastic elastomer gels as advanced substrates for construction of complex microfluidic networks suitable for use in miniaturized chemical analysis systems. These gels are synthesized by combining inexpensive polystyrene-(polyethylene/polybutylene)-polystyrene triblock copolymers with a hydrocarbon extender oil for which the ethylene/butylene midblocks are selectively miscible. The insoluble styrene end blocks phase separate into localized nanodomains, resulting in the formation of an optically transparent, viscoelastic, and biocompatible gel network that is melt-processable at temperatures in the vicinity of 100 degrees C. This unique combination of properties allows microfluidic channels to be fabricated in a matter of minutes by simply making impressions of the negative relief structures on heated master molds. Melt processability allows multiple impressions to be made against different masters to construct complex geometries incorporating multi-height features within the same microchannel. Intricate interconnected multilayered structures are also easily fabricated owing to the ability to bond and seal multiple layers by briefly heating the material at the bond interface. Thermal and mechanical properties are tunable over a wide range through proper selection of gel composition.

Biocompatible Materials↗
PubMed1996

Optimization of a continuous real-time computerized semen analysis system for ram sperm motility assessment, and evaluation of four methods of semen preparation.

Sampling conditions that affect the biological validity of computer-assisted analysis of ram sperm motion were examined using a continuous real-time computerized semen analysis system (Hobson Sperm Tracker). Search radius (SR, 10 settings) and minimum track point (MTP, 10 settings) were varied factorially to evaluate their effects on the inclusion of sperm subpopulations within derived datasets. Low SR (< 12 microns) or high MTP values (> 26 frames) precluded measurements of rapidly moving cells, whereas high SR (> 17 microns) and low MTP settings (< 22 frames) led to erroneous tracking and poor data quality. Suitable settings for these set-up parameters were derived and tested for their biological consistency with four methods of preparing ram semen for computerized analysis. The preparation techniques tested were: centrifugation through sucrose-based Ficoll and Percoll media, a swim-up technique and simple dilution in Tyrode's media. The "selective' Percoll and swim-up methods generated sperm populations with significantly higher linear velocities and a lower tendency to deviate from linear trajectories than from either the Ficoll method or dilution technique. Deleterious effects of centrifugation were evident, particularly on sperm survival in vitro over several hours. It is concluded that computer-assisted semen analysis provides useful information about the behaviour of ram spermatozoa in vitro, but the measurement conditions must be defined carefully.

Animals↗
PubMed1989

Reliability of the Genucom Knee Analysis System. A pilot study.

Instrumented knee laxity testing is now common practice in many orthopedic and rehabilitative practices around the country. The Genucom Knee Analysis System is marketed as a comprehensive quantitative knee joint laxity testing device. To examine the intrarater reliability of the Genucom, the authors evaluated five normal subjects, each on three independent occasions. All testing was done by a single examiner. Anteroposterior (AP) drawer, valgus/varus, and tibial rotation tests were performed. The average variability for repeated testing was determined and this variability was then used to estimate the smallest statistically significant difference for a single repeat examination that would represent true change, i.e., change over and above the inherent variability of the measurement. The results indicate that: (1) anterior drawer variability and tibial rotational variability are dependent on the knee flexion angle; (2) reporting anterior drawer may be more reproducible than reporting total AP motion; and (3) on average, changes exceeding 3 mm for anterior drawer tests, 5 mm for total valgus-varus motion, and 7 degrees-17 degrees of tibial rotation are needed to be 95% confident that the change in a measure from one time to the next is real and not due to measurement variability.

Adult↗
PubMed2004

[System approach and system analysis in dietology].

There is analysis of using of two variants of the auto-program of dietotherapy in the article: numeric system and basis system. They belong the same kind of building type, but are different in the type of functioning principle. Numeric system is built upon nosological principle taking into consideration the clinicopathogenetic features of disease. The basic diets built upon metabolic principle that a matter is adaptation of chemical content, alimentary and food value of diet for concrete mechanism of metabolic disturbance. At the same time metabolic conveyor is considered as system organization of the separate functional systems that are in the permanent dynamic and the interacting with each other. This organization is combined on the principle of auto regulation and set in correction and recovery of disturbed homeostasis as a whole. Selection of practical using of mentioned principles of diets is a right of the specialist-dieitian. Auto-program of diet building should help him in that and simplify the organization of dietotherapy.

Diet Therapy↗
PubMedDate not supplied

Application of expert systems analysis to interpretation of fatal cases involving amitriptyline.

Part I. Expert 4: The object of this study was to investigate the applicability of commercially available expert system shells to interpretation in forensic toxicology. Amitriptyline toxicology was selected as a pilot trial. Blood and tissue concentrations of amitriptyline and nortriptyline in fatal and nonfatal amitriptyline cases from the literature and from the Registry of Human Toxicology databank were entered into the expert system shell Expert 4 (Rivers, Elsevier). The statistical evaluation routines of the shell were used to search for patterns in the data. Successive changes in the data base were made to test for the influence of the data base on the conclusions. Finally the data base was refined, based on the evaluations, to strengthen the probabilities of the conclusions. The refined database was coupled with the Expert 4 inference engine to infer unknown parameters in the cases. The results of the expert system analysis were compared to known values and published expert opinions. The ratio of amitriptyline/nortriptyline and tissue levels of nortriptyline were found to be the most significant measures for interpretation of effect and time since ingestion. Part II. Computer Induction of Rules: Blood and tissue concentrations of amitriptyline and nortriptyline in fatal and nonfatal amitriptyline cases from the literature and from the Registry of Human Toxicology databank were entered into the expert system shell BEAGLE, (Forsyth, Machine Learning Research, Ltd.). The automatic rule induction routines of the shell were used to search for patterns in the data. The program expressed these patterns as numerical predictions or Boolean logic rules. The results were compared to those obtained with the Expert 4 (Rivers, Elsevier) using the same case knowledge base.(ABSTRACT TRUNCATED AT 250 WORDS)

Amitriptyline↗
PubMed1994

Automated monitoring of cell concentration and viability using an image analysis system.

In order to automate measurements of cell concentration and viability in a suspended animal cell culture, we have developed an in situ microscopic image analysis system with an effective cell recognition algorithm. With a small amount of sample, this system can measure the cell density rapidly and aseptically. In addition, it can measure a cell size histogram including cell debris small particle distribution. These small particles have been found to be related to the viability of the mouse-mouse hybridoma STK1 cell line. By using cell debris small particle density as an indicator of cell viability, the developed system provides non-destructive viability monitoring without trypan blue staining.

Animals↗
PubMed2004

A new noninvasive tear stability analysis system for the assessment of dry eyes.

PURPOSE: This was a prospective case-control study conducted to evaluate the effectiveness of the Tear Stability Analysis System (TSAS) for the assessment of patients with dry eye. METHODS: The TSAS can take 10 consecutive corneal topograms at one per second for 10 seconds. Examinations using the TSAS were conducted in 26 eyes of 26 healthy control subjects and in 27 eyes of 27 patients with dry eye. Examinations were also conducted in 14 eyes of 14 patients before and after the insertion of punctum plugs. Surface regularity and asymmetry indices (SRI, SAI), as well as new tear stability regularity and asymmetry indices (TSRI, TSAI), derived from SRI and SAI, were analyzed. RESULTS: The mean SRI and SAI in dry eyes were significantly greater than in control eyes (P < 0.05). The time-wise change of SRI and SAI was significantly different between dry eyes and control eyes (P < 0.05). TSRI and TSAI in dry eyes were also significantly greater than in control eyes. Punctum plug insertion was associated with a significant decrease in SRI and SAI (P < 0.05). CONCLUSIONS: TSAS was effective in objectively assessing the tear stability in patients with dry eye. This system may be useful in noninvasive diagnosis of dry eye and evaluation of treatment effects.

Case-Control Studies↗
PubMed1994

The glutamate biosensor and its application to flow injection analysis system.

A micro-enzyme electrode was fabricated by cross-linking L-glutamate oxidase with glutaraldehyde on aminopropyl-platinized platinum wire. A flow injection analysis system with glutamate sensor was used for L-glutamate determination. The peak current is linearly related to the L-glutamate concentration in the range of 0.02-2.0 mM, with good performance, accuracy (CV = 0.4%), fast response (< 60s), and stability (> 20 days). The system was applied to determine the concentration of L-glutamate in a fermentation broth. The recovery rate was in the range of 98.7-107.5%.

Amino Acid Oxidoreductases↗
PubMed2002

Horses for courses: facilitating postgraduate research students' choice of Computer Assisted Qualitative Data Analysis System (CAQDAS).

Supervisors of postgraduate students are increasingly likely to find themselves discussing whether or not the student should use a CAQDAS (computer assisted qualitative data analysis system) in their research. This paper discusses Weitzman and Miles (1995) framework for decision-making about CAQDAS and then reports the experiences of five postgraduate students, each of whom made a different decision. (These were variously: not to use a CAQDAS, using Atlas-Ti, Ethnograph, N. VIVO and N5). It explores the fit between Weitzman's and Miles' principles and the students' experiences then suggests some modifications of the principles and strategies for advising students.

Choice Behavior↗
PubMed1993

Application of a system analysis approach to population pharmacokinetics and pharmacodynamics of nicardipine hydrochloride in healthy males.

Nicardipine hydrochloride, a dihydropyridine calcium channel blocker, possesses antihypertensive and arterial vasodilator properties. A system analysis approach, which makes fewer structural assumptions than compartmental methods, is presented for determining the pharmacokinetics and pharmacodynamics of nicardipine hydrochloride in healthy males following a discontinuous infusion at four dose levels. The results indicate that the average total body clearance of nicardipine is 0.920 L/h/kg and the volume of distribution is 0.275 L/kg. Nicardipine hydrochloride has a mean residence time in the body of 1.27 h, of which 0.324 h were spent in the systemic circulation and the remainder in the periphery. The determined pharmacokinetic model was linked to a pharmacodynamic model that allowed the change in the mean arterial blood pressure and heart rate to be described and predicted. A population pharmacokinetic-pharmacodynamic model was derived and the predictive power of the proposed model was assessed with a cross-validation technique that employs a relative predictive quotient for comparing the predictions to the fitted model. The results indicate that the proposed model describes the pharmacodynamics of nicardipine in healthy males and has good predictive ability when tested with a cross-validation procedure.

Adult↗
PubMed2001

Cell analysis system based on immunomagnetic cell selection and alignment followed by immunofluorescent analysis using compact disk technologies.

BACKGROUND: Although the flow cytometer has become the standard in cell analysis, it has limitations. Recently, we introduced a new cell analysis method based on immunomagnetic selection and aligning of cells. No flow system is needed and cell analysis can be performed in whole blood. METHODS: Whole blood is incubated with fluorescent labels and immunomagnetic nanoparticles. The blood is injected into a capillary that is in a strong magnetic field. The immunomagnetic-labeled cells move upward and align themselves along ferromagnetic lines present on the upper surface of the capillary. An optical focus and tracking system analogous to that used in a conventional compact disk player focuses a 635-nm laser-diode on the magnetically aligned cells. The emitted fluorescence signals are projected on two photomultipliers. Allophycocyanin (APC)-labeled CD4 (CD4-APC) and Cyanin5.5 (Cy5.5)-labeled CD8 (CD8-Cy5.5) antibodies and Oxazine750, all red excited, are used as fluorescent labels. RESULTS: A differential white blood cell count performed in whole blood is obtained using the CD4-APC in combination with Oxazine750. The results are compared with the Technicon-H1 hematology analyzer. Correlation coefficients of 0.91 for neutrophilic granulocytes, 0.93 for lymphocytes, 0.93 for monocytes, and 0.96 for eosinophilic granulocytes were obtained. Immunofluorescence is demonstrated using CD4-APC and CD8-Cy5.5. The absolute counts obtained for CD4+ and CD8+ are compared with the Coulter Epics XL flow cytometer. Correlation coefficients of, respectively, 0.91 and 0.94 were obtained. CONCLUSION: We conclude that our system is as capable as a standard flow cytometer or hematology analyzer for a reliable routine white blood cell analysis, including immunophenotyping, and can be used as an easy-to-handle disposable white blood cell test.

CD4 Antigens↗
PubMed2005

Nurses' concerns about using information systems: analysis of comments on a computerized nursing care plan system in Taiwan.

AIMS AND OBJECTIVES: The purpose of this study was to pursue a deeper understanding of nurses' perceptions of a computerized nursing care plan as written in comments on a survey. BACKGROUND: Studies have examined nurses' perceptions of computer use, but comments written on surveys of computerized nursing care planning have never been reported and the pattern and meaning of such feedback have not been systematically analysed. DESIGN: Of 738 nurses in Taiwan who completed a two-part survey to evaluate a computerized nursing care plan, 202 responded on part II to an open-ended question about overall perceptions of a nursing information system. METHODS: A sample of 10 questionnaires with comments was subjected to qualitative content analysis. Key words and phrases were identified, then grouped into categories, which were used to code the remaining respondents' comments. Another 20 were used to pilot test these coding categories. The final coding categories were applied to all 202 questionnaires with comments for data analysis. RESULTS: Nurses were concerned about inconvenient access to computers; reduced work efficiency; inability to individualize patient care and nursing specialty deficiencies; poor content design, system function, and system integration; using the system as a policy requirement; and privacy and legal issues. CONCLUSIONS: Hardware availability, content design and user training/education programmes are critical issues that affect nurses' use of computers in their daily practice. RELEVANCE TO CLINICAL PRACTICE: These comments can be applied in strategic planning and staff development programmes to further use of information systems in patient care.

Adult↗
PubMed2004

Dental arch analysis system.

The purpose of our research is to describe a computerized method, which enables orthodontists and researchers to analyze variation of dental arch form and dimension. The analysis system is composed of two independent parts: the database, where the images of scanned dental casts are stored, and the software. The operator uses the software to identify some landmarks on dental cast images. Corresponding distances are calculated (interincisive, intercanine and intermolar widths and the curve axis). Then the software algorithms calculate and draw the curves passing trough the selected landmarks (conics, catenary, cubic spline and polynomial curves). In the chosen curves the arch length is measured. The dental cast data, recorded at different times of the subject's life or in different steps of orthodontic treatment, are compared in order to evaluate the change in dimension (arch length and width) and form (shape). The statistical analysis of the data evaluates the variation in form and in dimension separately. The shape change is defined by Euclidean Distance Matrix Analysis (EDMA) and Bootstrap analysis. The computerized method allows orthodontists and researches to evaluate the variation in dimension and form of the dental arch in un-treated subjects and-or orthodontic patients over time. After the analysis of a large sample of patients or subjects, information concerning changes in dental arch dimension and form can be added to previous studies of other authors, distinguishing variation during and after orthodontic treatment, during growth or aging.

Cephalometry↗
PubMed2006

Sequential flow injection analysis system on-line coupled to high intensity focused ultrasound: green methodology for trace analysis applications as demonstrated for the determination of inorganic and total mercury in waters and urine by cold vapor atomic absorption spectrometry.

A new concept is presented for green analytical applications based on coupling on-line high-intensity focused ultrasound (HIFU) with a sequential injection/flow injection analysis (SIA/FIA) system. The potential of the SIA/HIFU/FIA scheme is demonstrated by taking mercury as a model analyte. Using inorganic mercury, methylmercury, phenylmercury, and diphenylmercury, the usefulness of the proposed methodology for the determination of inorganic and total mercury in waters and urine was demonstrated. The procedure requires low sample volumes and reagents and can be further applied to all chemical reactions involving HIFU. The inherent advantages of SIA, FIA, and HIFU applications in terms of high throughput, automation, low reagent consumption, and green chemistry are accomplished together for the first time in the present work.

Biosensing Techniques↗
PubMed1986

Periosteal resorption and periosteal neostosis: comparison of normal subjects and renal failure patients on chronic ambulatory peritoneal dialysis using MOP-3 image analysis system and a grading method.

This is the first known attempt to quantitate periosteal resorption (PR) and perisoteal neostosis (PN) by a semi-automatic image analysis system (Zeiss MOP-3). The normal ranges and errors for PR were found to be similar to those of a previous study using a measuring magnifier. The findings in chronic renal failure patients showed that MOP-3 measurements were actually diagnostically slightly less sensitive than the results by a simple grading method. Comparison with plasma-immunoreactive parathyroid hormone (iPTH) concentrations showed that while the latter had a higher sensitivity for detection of hyperparathyroidism, the radiologic parameters nevertheless showed abnormal PR in 12% of the observations where iPTH was normal. Both PR and PN correlated significantly with iPTH (r = 0.55 and 0.30 respectively, P less than 0.01).

Adult↗
PubMed1980

The influence of preset integer intervals at the densitometer unit of the television texture analysis system (TAS) on DNA quantification.

The relative DNA content of Feulgen stained nuclei, or concentrations of stoichiometrically binding dyes can be determined by the television texture analysis system. This determination is based on the measurement of areas at preset integer intervals of transmittance. The method includes an unavoidable error in DNA quantification caused by the smallest preset integer value of transmittance at the densitometer unit. The error at the TAS is calculable by a theoretical reduction of the preset intervals for delta T. The calculation results in a correcting factor of 0 less than or equal to 4.1% of the whole measured area of a nucleus. The revised relative DNA content can now be calculated by D=E.A.1.041.

Cytological Techniques↗