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The current program in Quickbasic provides a valid and reliable computational method for the estimation of cardiac output, using the CO2 rebreathe method. In addition, this program will save time through speed of execution. Furthermore, the program can be used with IBM microcomputers as well as IBM compatible microcomputers.
We developed an easy-to-operate computer program for the IBM personal computer to calculate, display and store in a database platelet kinetic data determined by analysis of the rate of clearance of radiolabeled blood platelets from the circulation. This was done by curve fitting using the weighted mean method and multiple-hit model. These models are complementary and calculating the mean platelet survival time with both is recommended. Improvement of the weighted mean method was investigated. The optimized weighting and fitting the exponential function with the Marquardt non-linear least squares method improved the weighted mean method. The weighted mean and multiple-hit models fit the survival curve data equally well. The calculation of the mean platelet survival time with the weighted mean method was very fast. The duration of calculation with the multiple-hit model could take up to 2 minutes. Calculation of the mean platelet survival time using both models has the advantage that conditions when calculation of the mean platelet survival time would be invalid, can be detected. The computer program will promote the valid comparison of results obtained at different institutions.
The program is designed for analysis of serial microtome sections containing biological structures (bodies, particles), each of which may be represented as one point. Any subset of sections may quickly be selected for reconstruction. In addition to rotation, translation, scaling etc. two particular features are offered. (1) Section-independent parts of reconstructions may be isolated ("windows") and then reconstructed, analyzed and subdivided, like the parent data. (2) Curved, bandshaped parts may be unfolded, for inspection of distribution pattern, determination of density etc. The program is written in Pascal (source 121 Kb, compiled program 65 Kb). User-friendliness, robustness and speed were key aims.
A BASIC program is presented which facilitates the formulation of biologically relevant chemical solutions containing specified free concentrations of as many as three divalent metal cations (Ca2+, Mg2+ and the choice of a third divalent cation) at any pH in the presence of as many as three ligands (EGTA, ATP and GTP). The program uses the law of mass action and the absolute stability (association) constants found in the literature to calculate the total concentration of divalent metal cation needed to achieve a desired free concentration. The user enters the pH, the concentrations of the ligands used and the desired free concentrations of the divalent cations. This program was developed for use in a wide range of biological applications, particularly the rapid design of solutions which mimic certain aspects of intracellular fluid.
Analog/Digital conversion of up to 16 channels can be set up and executed interactively with sampling rates individually adjusted for each channel. Additionally, asynchron and parallel digital I/0 is provided, including the possibility of triggering the beginning and the end of data acquisition on an external TTL signal. For non-experienced personnel the package can be run fully interactively with help-menus. Conversely, the experienced user can skip the menu level and directly access the A/D conversion card at the programmers' level in FORTRAN, BASIC or PASCAL. This two level approach considerably enhances the versatility of the package. Data structures in memory and on disk are the same for both levels. Thus, data acquired in menu mode can be compatibly accessed and evaluated from the menu--as well as the programmers' level. Furthermore, a concept is presented for a most efficient and convenient transfer of pre-processed data onto an IBM-mainframe for further analysis in SAS. This transfer scheme allows for continued transparency of the data files, should--for technical reasons or due to changes in the type of data acquired--changes or upgradings of the A/D conversion software become necessary. The package is available for IBM-XT/AT personal computers.
The analysis of unbalanced two-way analysis of variance model using a parametric ANOVA (F-test) is compared to two nonparametric tests (extensions of the Quade and Friedman tests). Results from a Turbo Pascal program written for MS-DOS microcomputers are given for a biomedical experiment using ultrasound data to calibrate heart valve measurements.
A BASIC computer program for calculating ED50 and LD50 values and their confidence limits by probit analysis and weighted linear regression is presented. It also includes the Chi square procedure for testing the mathematical model and allows on-screen high resolution graphic display. The portable program can easily be modified for use in different models of microcomputers.
Two sets of programs written using SPSS-X, and designed for the analysis of data obtained by radioimmunoassay or radioreceptorassay are presented. The main advantages of the programs are that they are easily edited, their commands are simple and logical, and they can be used for any type of radioimmunoassay or radioreceptorassay, respectively. The programs for radioimmunoassay can also be used for fluorescenceimmunoassay and luminescenceimmunoassay.
A BASIC computer program to assess the time-dependent prognostic status of patients in follow-up studies is described. At each point in time, patients should be in one of two mutually exclusive conditions of interest, e.g. some biochemical measurement is within normal limits or not. The method is applied to data from a clinical study to investigate the prognostic effect of a rebleed in cases with oesophageal variceal bleeding.
A program in QuickBasic has been written for the purpose of simulating spermatogenesis in any animal in order to more fully understand the dynamics of sperm production. Two basic informations are needed to run the program: controlling factors (CF-s) and the stem cell population size. These can be interactively manipulated for theoretical evaluations or be implemented from actual animal data for assessment of valid sperm yield.
In this paper we present a set of programs resulting in a management system for a Database in experimental medicine. The programs are written in Fortran and they run in a VAX 8200 of DEC. We have successfully applied this management system in the study of mechanics and of the electrical activity of the muscles of the respiratory apparatus. However, it may be used in other fields of experimental medicine since it has been structured in such a way as to be easily adapted; in addition it may run in other computers.
Receiver-operator characteristic (ROC) curve analysis has become an accepted method of evaluating the efficiency of clinical laboratory tests. The calculations necessary to plot such curves are not difficult, but are repetitive and time consuming. Such calculations are easily done by computers. The availability, ease of use and graphics capabilities of spreadsheet programs such as Lotus 1-2-3 lend themselves to these applications. In this article, we describe such an application.
Computer-derived spreadsheet programs such as Lotus 1-2-3 are being used by many investigators for individualized statistical calculations. Spreadsheet templates have been described for the performance of simple statistical tests by non-statisticians with relatively limited computer experience. This paper describes a template for use with Lotus 1-2-3 for automatic graphic display of confidence and prediction intervals of simple linear regression analysis. The graph can be printed using the Lotus printgraph program. The program also allows comparison of the slope and the intercept of two regression lines.
Significant features are described of a Monte Carlo simulation system, LINKERS, that generates nuclear family data conforming to one locus and two loci genetic models. Software engineering techniques help to produce a user friendly environment for studies of genetic ascertainment. LINKERS' 39 code modules are maintained and optimized using VAXset. Within a VAX/VMS workstation environment LINKERS generates a useful population of 10,000 families in 1 min. An example is presented to illustrate the use of LINKERS. Generated data were analysed using the segregation program POINTER. Likelihood ratio tests showed the effects of multiple alleles, gene frequency and incorrect specification of disease prevalence.
The CPU time required to complete a cycle of restrained least-squares refinement of a protein structure from X-ray crystallographic data using the FORTRAN codes PROTIN and PROLSQ are reported for 48 different processors, ranging from single-user workstations to supercomputers. Sequential, vector, VLIW, multiprocessor, and RISC hardware architectures are compared using both a small and a large protein structure. Representative compile times for each hardware type are also given, and the improvement in run-time when coding for a specific hardware architecture considered. The benchmarks involve scalar integer and vector floating point arithmetic and are representative of the calculations performed in many scientific disciplines.
Concentration gradients are often used in separations based on chromatographic, electrophoretic and centrifugal methods. In this report, a BASIC computer program for calculating and graphically representing gradients is described. This GRADIENT program is intended to be run on IBM-compatible computers.
This software program adds two very interesting data to the usual results of exercise testing: an estimation of cardiac output according to the most recent validations and a reliable estimation of alveolar ventilation. The main advantage of this additional ventilatory and cardiovascular information using the same data: end-tidal PCO2.
The Diagnostic Encyclopedia Workstation (DEW) contains reference knowledge for diagnostic support in pathology. Illustrations are accessible via a video disc device. DEW can hold more knowledge, pictures and case histories than books, and its information is accessible via several entries. Software for data entry has been written in MUMPS with use of the relational database toolkit AIDA, which is particularly suited for manipulation of free text. The graphical mouse-driven user interface is written in C using MetaWindows. The DEW contains 85 diagnoses in ovarian pathology, covering all frequent cases and many rarities, illustrated by approximately 3000 pictures, divided among 158 cases.