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PubMedDate not supplied

The Statistical Package for the Social Sciences (SPSS) as an adjunct to pharmacokinetic analysis.

Computer techniques for numerical analysis are well known to pharmacokineticists. Powerful techniques for data file management have been developed by social scientists but have, in general, been ignored by pharmacokineticists because of their apparent lack of ability to interface with pharmacokinetic programs. Extensive use has been made of the Statistical Package for the Social Sciences (SPSS) for its data handling capabilities, but at the same time, techniques have been developed within SPSS to interface with pharmacokinetic programs of the users' choice and to carry out a variety of user-defined pharmacokinetic tasks within SPSS commands, apart from the expected variety of statistical tasks. Because it is based on a ubiquitous package, this methodology has all of the benefits of excellent documentation, interchangeability between different types and sizes of machines and true portability of techniques and data files. An example is given of the total management of a pharmacokinetic study previously reported in the literature by the authors.

Computers↗
PubMed1995

Age and seasonal effects on Holstein yield for four regions of the United States over time.

Multiplicative factors to adjust Holstein yield for age and season of calving were calculated and analyzed from 20 data files for region and time. Regions were 1) California, 2) Minnesota and Wisconsin, 3) New York and Pennsylvania, and 4) six southern states (Texas, Louisiana, Mississippi, Alabama, Georgia, and Florida). Time periods were calving years of 1964 to 1968, 1971 to 1975, 1976 to 1980, 1981 to 1985, and 1986 to 1990. The same statistical model was used that had been used to derive current USDA factors from 1964 to 1968 data. The number of lactation records for each data file ranged from 81,394 to 2,238,201 and increased with time. Effect of calving season on milk yield generally decreased with time; the largest decrease was for the southern region. Effect of calving age also generally decreased for recent data, and the largest decreases were for California. Updated factors to adjust yield for calving age and season are indicated for some regions.

Aging↗
PubMed1995

The use of microsoft excel as a user interface for biological simulations.

We used Microsoft Excel 4.0 for Windows running on a PC-486 to develop a user interface for two biological simulation models: a lung fluid balance model and a fractal model of the pulmonary circulation. The simulation programs were written in the C programming language, while the user interface was written in the macro language of Excel. The interface builds input data files for the simulation programs and provides a mechanism for displaying relevant information from output files produced from the simulations. Input fields are partially protected so that the user cannot modify certain portions of the spreadsheet. The Excel interface is used to build models from different available components and to select appropriate parameters for these models. The developed interface was also useful for running models in the batch mode. After selecting changes in lung fluid balance parameters, the interface allows users to find new steady state values by automatically running the model and adjusting initial conditions. Several different graphical options allow users to easily investigate the effects of selecting particular models and parameters. Techniques used in developing our user interface can be extended to most biological simulation programs which manipulate input and output data files.

Computer Graphics↗
PubMed2005

Burn injury in children.

The authors have analyzed the data files of 580 child patients up to 15 years of age who were hospitalized at the Burn Center of the FNsP Hospital in Ostrava in the years 1999 - 2003. The authors focused on mechanisms of burn injury in relation to the age of a child as well as extent, depth, localization, and local treatment of the injury. The data file was divided to four age groups: up to two years of age, 2 - 5 years of age, 5 - 10 years of age, and 10 - 15 years of age. As regards the mechanisms of injury, the authors have analyzed scalding by hot liquids, burns due to contact with a hot object, burns due to electric current, explosion, and injury caused by burning clothing. Injury by scalding prevails to a very significant degree in the youngest children. In the second age group the incidence of burn following contact with hot objects increases, as does the percentage of children injured by burning of clothing in children aged 5 - 10. The older children have increased prevalence of injuries caused by explosions. The greatest average extent of an injury is from burning of clothing. Most of the areas are burned deeply, localized in more areas of the body, and almost half of the cases required surgical intervention. Scalding comes second in terms of average extent of an injury. More than half of the injured areas are superficial, and areas of injury are different in the individual age groups. We addressed about a fifth of the cases surgically. The explosion of combustible materials caused a smaller extent of injury, on average, taking third place. The injuries were predominantly superficial, most commonly involving the head, trunk, and upper extremities. In none of the cases it was necessary for us to operate. Burn injuries caused by contact with hot objects are of a smaller extent. More than half of the burned areas are deep, localized most commonly in the upper extremities. Surgical intervention was necessary in more than half the cases. In terms of average extent of an injury, the smallest burn injuries are caused by electric current. However, these injuries are deep, and surgical intervention was necessary in all cases.

Adolescent↗
PubMed1997

Analysis of productive life in Swiss brown cattle.

An analysis of productive life of Swiss Brown cattle was performed using a mixed survival model based on Cox regression. Data included 52,862 daughters of 297 sires. The length of productive life was observed from May 1, 1985 through August 15, 1995. Records on cows that were still alive in the end of study (32.4%) were treated as censored. The probability of being culled (hazard) was defined as a product of a baseline hazard function and a function of explanatory variables. In addition to sire effects, the model included effects of age at first calving and the time-dependent variables herd by year, lactation number, stage of lactation, and milk production within the herd to account for culling because of low production. Solutions for fixed effects indicated a higher probability of being culled for primiparous cows, for cows in the end stage of lactation, and for cows with low production. The impact of censoring on the accuracy of estimation was investigated by computing the rank correlations between the estimated transmitting abilities (ETA) of sires using a simplified model from uncensored data (reference) and the ETA from several different data files with an increased proportion of censored records. The rank correlations among sire ETA decreased as number of daughters per sire decreased and as the proportion of censored records increased. The maximum number of censored records that is acceptable to obtain accurate results is 30 to 40%. The acceptable proportion of censored records would be higher if the reference ETA were obtained on a larger data file using daughters of old sires.

Animals↗
PubMed2005

Critical and severe burn injury in children.

The authors present a data file of 279 children with severe and critical burn injury, hospitalized in the Intensive Care Unit or the Pediatric Resuscitation Unit of the FNsP Hospital in Ostrava in the years 1999 - 2003. The severity of the burn trauma in children is determined by age, extent, depth, localization, circumstances of the injury, its mechanism, and by other serious illnesses of a child. The authors have divided the data file into two groups, severe and critical, using classification of a burn injury in children according to the extent of injury as well as localization and other circumstances (1). Complex therapy of extensive burn injuries in children is based on adequate fluid resuscitation, treatment of burned areas, algosedation, and appropriate antibiotic therapy. The authors have unequivocally confirmed that in the group of children with diagnosis of critical burns complications occur more often, while the overall course of illness is serious and requires more therapeutical interventions than in the group of children with severe burns.

Burns↗
PubMed2001

Differences in rehabilitation services and outcomes among stroke patients cared for in veterans hospitals.

OBJECTIVE: To examine the relationship of services for post-acute care (PAC) to stroke patient outcomes. DATA SOURCES/STUDY SETTING: Veterans Health Administration (VHA) hospitals from two facility-level surveys and extant data files. STUDY DESIGN: Cross-sectional study of veterans hospitalized with acute stroke during the period June 1995 through May 1996 in one of 182 geographically distinct locations within the VHA. Study variables included (1) a typological classification of hospitals according to the level of PAC; (2) a taxonomy of rehabilitation characteristics, including personnel, physical facilities, coordination of care, and hospital characteristics; and (3) patient outcomes (discharge destination, length of stay). DATA COLLECTION/EXTRACTION METHODS: Data were collected from two mailed surveys and extant data files. Rehabilitation variables were identified for the study in conjunction with a panel of expert rehabilitation researchers and clinicians, using an a priori model for measuring rehabilitation characteristics. Two sets of variables were derived to categorize these rehabilitation characteristics: (1) a rehabilitation typology, classifying the VA hospitals according to the continuum of PAC settings in the facility, and (2) a rehabilitation taxonomy that used an empirical approach to derive a list of key rehabilitation characteristics. PRINCIPAL FINDINGS: Twenty-seven percent of veterans with acute stroke were cared for in VA hospitals with neither a geriatric nor a rehabilitation unit, and 50 percent were cared for in hospitals without a rehabilitation unit. Hospitals with rehabilitation units had the greatest sophistication, and those with geriatric units had intermediate sophistication in rehabilitation organization and resources. Statistically significant differences were found in outcomes for stroke patients cared for in hospitals classified according to the continuum of post-acute care on site. Exploratory multivariable analyses revealed independent associations between stroke patient outcomes and (1) staffing ratios for nurses and physicians, (2) the diversity of physician and rehabilitation staff, (3) presence of a simulated home environment, and (4) the total number of care settings on site. CONCLUSIONS: The PAC continuum defines an important hierarchy of stroke rehabilitation services.

Aged↗
PubMed2003

SLControl: PC-based data acquisition and analysis for muscle mechanics.

SLControl is a computerized data acquisition and analysis system that was developed in our laboratory to help perform mechanical experiments using striated muscle preparations. It consists of a computer program (Windows 2000 or later) and a commercially available data acquisition board (16-bit resolution, DAP5216a, Microstar Laboratories, Bellevue, WA). Signals from the user's existing equipment representing force, fiber length (FL), and (if desired) sarcomere length (SL) are connected to the system through standard Bayonet Neill Concelman cables and saved to data files for later analysis. Output signals from the board control FL and trigger additional equipment, e.g., flash lamps. Windows dialogs drive several different experimental protocols, including slack tests and rate of tension recovery measurements. Precise measurements of muscle stiffness and force velocity/power characteristics can also be accomplished using SL and tension control, respectively. In these situations, the FL command signal is updated in real time (at rates > or =2.5 kHz) in response to changes in the measured SL or force signals. Data files can be exported as raw text or analyzed within SLControl with the use of built-in tools for cursor analysis, digital filtering, curve fitting, etc. The software is available for free download at http://www.slcontrol.com.

Algorithms↗
PubMed1998

Use of a constraint satisfaction network model for the evaluation of the methadone treatments of drug addicts.

Constraint Satisfaction Networks were used by Semeion, a Research Center of Science of Communication, in order to analyze drug-addict patient data files, provided by the Jerusalem Methadone Treatment Center. The short and partial analysis carried out in this article is presented to show how this high technology can be a support for treatment staff in order to improve the quality and the timeliness of the necessary intervention with patients. One of the problems for which the networks could offer support is, for example, the individuation or "matching" of the most suitable therapy for the patient during the treatment planning phase. In this field the networks need to analyze data files of patients in therapy at different centers, with the results collected after many years of observation. What follows, obviously, only has demonstrative values.

Adult↗
PubMed1997

Genetic correlations between longevity and conformation traits in an upgrading dairy cattle population.

Genetic correlations between longevity and conformation traits were estimated using data on Dutch Black and White cows born in 1978 (11,558 records), 1982 (39,252 records), and 1989 plus 1990 (58,864 records). Longevity traits considered were number of lactations, herd life, and stayabilities until 36 and 48 mo of age and their functional equivalents (i.e., the longevity traits corrected for production). For the 1989 plus 1990 data file, only stayabilities until 36 and 48 mo of age were considered. Conformation traits were rear legs set, front teat placement, udder depth, suspensory ligament, and subjective scores for udder, feet and legs, and type. Also investigated was a possible nonlinear relationship between conformation and longevity traits. Genetic correlations between conformation and longevity traits differed between years of birth, mainly because farmers practiced large-scale upgrading with Holstein-Friesian bulls during the period considered, which caused a change in desired type. Therefore, the predictive value of conformation traits for longevity based on data from an upgrading population, might be limited. Estimates of genetic parameters should be based on the most recent data possible, and these parameters should be reestimated over time. From the 1989 plus 1990 data file, subjective scores for udder and feet and legs had the highest predictive values for functional longevity. Quadratic relationships between conformation and longevity traits did exist, but generally the linear relationships prevailed.

Animals↗
PubMed2002

Comparative evaluation of the DPX and DPX-IQ lunar densitometer systems following software upgrade.

Bone densitometry research departments perform system and software upgrades infrequently in order to maintain high precision. This study compares the results obtained on a Lunar densitometer with DPX, and DPX-IQ installed to achieve year 2000 compliance. The DPX-IQ provides an improved femur edge detection algorithm with an expanded reference database. Two hundred data files for each measurement site acquired on DPX were reanalyzed on DPX-IQ. There was no change to the bone mineral density (BMD), bone mineral content (BMC), T-scores or Z-scores for the L2-L4 spine, radius (ultradistal and 33%), and total body. There was a significant high correlation for the femoral neck BMD (r = 0.98; p < 0.05). The mean differences in BMD, BMC, T-scores, and Z-scores at the femoral neck and Ward's and trochanteric regions were not significant (p > 0.05). The limits of agreement within the 95% confidence interval for the femoral neck BMD using the Bland and Altman method was between -0.057 and 0.063 g/cm(2). This order of magnitude magnifies the long-term precision error and alters the usual confidence limits for interpretation of true change in densitometry practice. Therefore, it is important for reanalysis of DPX data files with the DPX-IQ to be performed so that longitudinal changes in BMD can be accurately assessed.

Absorptiometry, Photon↗
PubMed1996

SEAVIEW and PHYLO_WIN: two graphic tools for sequence alignment and molecular phylogeny.

SEAVIEW and PHYLO_WIN are two graphic tools for X Windows-Unix computers dedicated to sequence alignment and molecular phylogenetics. SEAVIEW is a sequence alignment editor allowing manual or automatic alignment through an interface with CLUSTALW program. Alignment of large sequences with extensive length differences is made easier by a dot-plot-based routine. The PHYLO_WIN program allows phylogenetic tree building according to most usual methods (neighbor joining with numerous distance estimates, maximum parsimony, maximum likelihood), and a bootstrap analysis with any of them. Reconstructed trees can be drawn, edited, printed, stored, evaluated according to numerous criteria. Taxonomic species groups and sets of conserved regions can be defined by mouse and stored into sequence files, thus avoiding multiple data files. Both tools are entirely mouse driven. On-line help makes them easy to use. They are freely available by anonymous ftp at biom3.univ-lyon1.fr/pub/ mol_phylogeny or http:@acnuc.univ-lyon1.fr/, or by e-mail to galtier@biomserv.univ-lyon1.fr.

Animals↗
PubMed2003

Educational programs in US medical schools, 2002-2003.

CONTEXT: To better provide medical students with the knowledge, skills, attitudes, and values they will need as physicians, US medical schools continue to make ongoing changes to their staffing and curricula. OBJECTIVE: To review the status of US medical education in the 2002-2003 academic year, compared with 1997-1998. DATA SOURCES: The Liaison Committee on Medical Education (LCME) Annual Medical School Questionnaire, the Association of American Medical Colleges (AAMC) Databook, and the AAMC Data Warehouse: Applicant Matriculant File. Data evaluated included those on medical school faculty, applicants, and students; curriculum hours devoted to new multidisciplinary or nontraditional subject areas (eg, cultural diversity, evidence-based medicine, medical ethics, medical informatics); and methods used to evaluate student learning. DATA SYNTHESIS: The number of full-time faculty members in the 126 LCME-accredited medical schools increased from 96 773 in 1997-1998 to 109 526 in 2002-2003 (+13.2%). The number of applicants entering decreased from 43 016 in 1997-1998 to 33 625 in 2002-2003 (-21.8%). The number of enrollees remained virtually unchanged from 1997-1998 (66 748) to 2002-2003 (66 677). Most medical schools have incorporated new subject areas into their curricula, although time devoted to these areas varies across schools. Schools typically use written examinations (National Board of Medical Examiners subject tests and/or internally prepared examinations) to assess factual knowledge, and observations by faculty members and residents to assess clinical skills. Use of standardized methods (eg, an objective structured clinical examination [OSCE]) to assess clinical skills is variable; 82 schools use a final third- or fourth-year comprehensive OSCE; 53 require a passing OSCE score for graduation. CONCLUSIONS: While the number of applicants to US medical schools has continued to decline, student numbers are constant. The number of full-time faculty members has increased. Schools are incorporating new subject areas into their curricula, and the use of standardized methods of assessing clinical skills, while variable, is generally increasing.

Adult↗
PubMed1988

EZ-FIT: a practical curve-fitting microcomputer program for the analysis of enzyme kinetic data on IBM-PC compatible computers.

EZ-FIT, an interactive microcomputer software package, has been developed for the analysis of enzyme kinetic and equilibrium binding data. EZ-FIT was designed as a user-friendly menu-driven package that has the facility for data entry, editing, and filing. Data input permits the conversion of cpm, dpm, or optical density to molar per minute per milligram protein. Data can be fit to any of 14 model equations including Michaelis-Menten, Hill, isoenzyme, inhibition, dual substrate, agonist, antagonist, and modified integrated Michaelis-Menten. The program uses the Nelder-Mead simplex and Marquardt nonlinear regression algorithms sequentially. A report of the results includes the parameter estimates with standard errors, a Student t test to determine the accuracy of the parameter values, a Runs statistic test of the residuals, identification of outlying data, an Akaike information criterion test for goodness-of-fit, and, when the experimental variance is included, a chi 2 statistic test for goodness-of-fit. Several different graphs can be displayed: an X-Y, a Scatchard, an Eadie-Hofstee, a Lineweaver-Burk, a semilogarithmic, and a residual plot. A data analysis report and graphs are designed to evaluate the goodness-of-fit of the data to a particular model.

Enzymes↗
PubMed1997

Image processing for femoral endosteal anatomy detection: description and testing of a computed tomography based program.

A computed tomography (CT)-based image processing computer program was developed for three-dimensional (3D) femoral endosteal cavity shape modelling. For the examinations 50 cadaver femora were used. In the CT imaging 30 axial slices were taken above and below the lesser trochanter area from each femur. Different image analysis methods were used for femoral cavity detection depending on the structure of the processed slice. In the femoral shaft area simple thresholding methods succeeded, but in the problem areas of the metaphyseal femur edge, detection operators and local thresholding were required. In contour tracking several criteria were used to check the validity of the border pixels. The results were saved as four output data files: (i) a file for the longest anteroposterior (ap), mediolateral (ml) and oblique diameters computed by a Euclidian method, (ii) and (iii) files for 2D and 3D data respectively, and (iv) a file for centre points of each slice. Finally, testing of the results and dimensions obtained from the image analysis were carried out manually by sawing the femora into 10 stipulated horizontal slices. The ap and ml dimensions were measured with a caliper ruler. The CT-based image processing yielded a peak distribution of dimensions with a negative difference to those obtained in manual measurements. The mean difference between the image processing and the manual measurements was 1.1 mm (+/-0.7 mm, +/-1 SD). The difference was highest in the proximal slices of the femora of group I (with lowest cortical thickness), i.e. 1.3 mm (+/-0.8 mm) and lowest in the distal slices of the femora from group III (with highest cortical thickness), i.e. 0.9 mm (+/-0.6 mm). The results are acceptable for further use of the program to study endosteal anatomy for individual femoral component selection and designing basis.

Cadaver↗
PubMed1990

Pharmacokinetics of cefodizime: a review of the data on file.

Cefodizime is a new aminothiazolyl cephalosporin which may be administered iv or im. The absolute bioavailability im is almost 100%. The mean volume of distribution is approximately 6.2-8.51. Protein binding of cefodizime is 73-89% over the plasma concentration range. Cefodizime penetrates into several tissues and body fluids such as lung, sputum, pleural and ascitic fluids, prostate, kidney, and urine to give concentrations often exceeding the MICs of susceptible pathogens. Total body clearance is low (35-52 ml/min) and clearance is predominantly renal with up to 80% of an iv dose recovered unchanged in the urine. The pharmacokinetics are linear within the range of doses studied (0.5-2 g). The plasma concentration profile is best described by a triple exponential function. The ranges of half-lives reported are as follows: the distribution half-life is 0.2-0.5 h (accounting for 6-15% of the AUC), the beta half-life is 1.5-2.1 h (accounting for 56-76% of the AUC), and the terminal (gamma) half-life is 3.9-7.9 h (accounting for 18-43% of the AUC) After 2 g bd for five days in healthy volunteers, steady state was reached on the second administration, and no accumulation of the drug was noted. The total clearance is about 20% less in elderly subjects than in young adults, but no dosing adjustment is needed in the elderly. The pharmacokinetic profile is significantly altered in patients with a creatinine clearance less than 30 ml/min (three- to five-fold increase in half-life). Accordingly, the dose should be reduced to 50% of normal, at the same dosing interval.(ABSTRACT TRUNCATED AT 250 WORDS)

Biological Availability↗
PubMed2002

A new graphical user interface for fast construction of computation phantoms and MCNP calculations: application to calibration of in vivo measurement systems.

The paper reports on a new utility for development of computational phantoms for Monte Carlo calculations and data analysis for in vivo measurements of radionuclides deposited in tissues. The individual properties of each worker can be acquired for a rather precise geometric representation of his (her) anatomy, which is particularly important for low energy gamma ray emitting sources such as thorium, uranium, plutonium and other actinides. The software discussed here enables automatic creation of an MCNP input data file based on scanning data. The utility includes segmentation of images obtained with either computed tomography or magnetic resonance imaging by distinguishing tissues according to their signal (brightness) and specification of the source and detector. In addition, a coupling of individual voxels within the tissue is used to reduce the memory demand and to increase the calculational speed. The utility was tested for low energy emitters in plastic and biological tissues as well as for computed tomography and magnetic resonance imaging scanning information.

Calibration↗
PubMed2004

Minimum sample frequency for multichannel intraluminal impedance measurement of the oesophagus.

In all systems for impedance monitoring signals are stored in digital format after analog-to-digital conversion at a predefined rate, the sample frequency. We aimed to find the minimum sample frequency required to evaluate oesophageal transit and gastro-oesophageal reflux studies using impedance monitoring. In 10 healthy subjects and five patients with gastro-oesophageal reflux disease impedance signals were acquired during a 90-min postprandial period, using a sample frequency of 1000 Hz. Additionally, 10 liquid swallows were recorded in the healthy subjects. A dedicated computer program was used to derive, from the original 1000-Hz files, series of new data files with sample frequencies of 500, 200, 100, 50, 20, 10, 8, 5 and 4 Hz. In all of these files, liquid and gas reflux events were identified. In the analysis of the swallows, bolus head advance time (BHAT) and total bolus transit time were measured. Reflux events were detectable down to a sample frequency of 50 Hz. In transit analysis errors for BHAT at frequencies below 8 Hz errors exceeded 2.5%. Therefore, in impedance monitoring the minimum sample frequency is 50 Hz for the detection of reflux and 8 Hz for the evaluation of oesophageal transit.

Adult↗