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At least 487 records · Page 27Linked to original sources
PubMed1987

A new blood pressure measuring apparatus equipped with a microcomputer system for conscious rats.

In order to measure the systolic blood pressure of conscious rats without thermal stress, a highly sensitive pulse sensor was developed using a light-emitting diode-photo diode system. The combination of this pulse sensor and microcomputer system led to the development of a six-channel automatic blood pressure measuring apparatus for rats. It can measure the systolic tail arterial pressure of conscious rats at 28-30 degrees C. The relationship between direct carotid arterial pressure (Y) and indirect tail arterial pressure (X) in conscious spontaneously hypertensive rats can be expressed as follows: Y = 0.95X + 19.9 (mm Hg, r = 0.988, 28 degrees C). The new apparatus was also used to confirm the acute hypotensive effects of hydralazine, nifedipine, and pindolol in spontaneously hypertensive rats and the subacute antihypertensive effect of trichlormethiazide in desoxycorticosterone/saline hypertensive rats.

Animals↗
PubMed1988

A simple microcomputer interface for tail-flick determination.

An inexpensive means of tail-flick latency data acquisition and analysis using an Apple IIe microcomputer and three simple interface circuits is described. Descriptions of the software and hardware are provided with schematics and program listings. The measurement, storage, and analysis of the data are integrated in one system.

Animals↗
PubMed1988

High resolution on-line analysis of cardiac action potentials using a Motorola 68000 microcomputer.

We have developed a microcomputer system for the instantaneous on-line analysis of cardiac action potentials (APs) based on a Motorola 68000 microprocessor and 50 kHz A/D converter. This system can accurately analyze APs from all parts of the heart, including the extremely fast upstrokes of APs from Purkinje fibers. Facilities for tabulation of results, production of hard-copy plots of APs, pooling of experimental data, and statistical analyses are available off-line. The routine use of this system in our laboratory has greatly increased the accuracy and throughput of these time-consuming experiments.

Action Potentials↗
PubMed1986

A microcomputer program for hydrophilicity and amphipathicity analysis of protein antigens.

A simple and ready-to-use program to analyze hydrophilicity and amphipathicity characteristics of protein sequences is described. Three of the most commonly used hydrophilicity scales can be selected and the block length can also be varied. The program is written in BASIC language, can be run on any microcomputer and does not require computer experience. The program output is exemplified by a sample of lysozyme hydrophilicity and amphipathicity analysis.

Computers↗
PubMed1983

A low-cost microcomputer-based data acquisition and analysis system for an electron spin resonance spectrometer: data handling of dilute spin labeled nucleic acids.

This article describes the construction of an inexpensive and reliable data acquisition system for a Varian E-line Century Series ESR spectrometer utilizing an Apple II Plus microcomputer. All necessary hardware is readily available and used without modification. A BASIC program for routine collection, display, plotting and disk storage of experimental data has been written and subsequently compiled into machine code for high speed operation. The interface offers distinct advantages in spectral resolution as well as instrument control. An example of signal enhancement via computer controlled time averaging is presented for a spin labeled DNA experiment. The technique has recently been applied to studies of relative binding affinities of gene-32 protein for various spin-labeled polynucleotides.

Bacteriophage lambda↗
PubMed1987

Automation of protein assays with a microcomputer interfaced to a spectrophotometer.

We have developed a system for semi-automatic protein quantitation assays based on an inexpensive, general-purpose microcomputer. A commercial curve fitting program was modified for direct data input from the spectrophotometer via an analog to digital converter. The software provides specific prompts for protein assays resulting in a rapid and user friendly, semi-automated system. A listing of the protein assay results are printed, or stored to a magnetic disk, along with a graphic representation of the standard curve.

Autoanalysis↗
PubMed1983

A simple microcomputer-based three-dimensional serial section reconstruction system (MICROS).

We have developed a computer system which enters and aligns serial sections and displays the completed reconstructions at different rotations in space. The system uses commercially available hardware, including a Hewlett-Packard 9845T microcomputer and an H-P 9874A digitizer. The software for the system is written in the BASIC language. The system consists of two programs, one for section digitization, the other for rotation and display of the reconstructions. Sections are digitized directly from micrographs or back-projected slides. The outlines of cells or other structures are traced from these media using a hand-held cursor on the digitizer. The positions of elements (inputs) which contact the structure and fiducials are also digitized. The sections are aligned by simultaneously displaying two consecutive sections on the graphics CRT screen. The sections are coarsely superimposed by centering around screen center using a centering algorithm. They are precisely aligned by rotating and translating the images with a reference cursor. Special functions for inserting and deleting sections and rapid section scanning are available for editing. The aligned sections are stored using a linked-list file structure on either floppy disks or tape cartridges. The rotation program replots the completed reconstructions on the graphics CRT or digital plotter. The program will reproduce the reconstructions at any scale and at any rotation in the x-, y- or z-planes. A hidden line algorithm removes hidden lines to give a 3-dimensional (3-D) perspective to the reconstructions. The positions of inputs and fiducials are represented by symbols. We use the system to reconstruct cells and neural processes. The 3-D reconstructions allow us to: (a) examine the spatial distribution and density of synaptic contacts on neurons; (b) study complex neuronal shapes; (c) examine the vectors of neural processes. The computer reconstruction system, which is moderately priced, should also prove useful for reconstructing many other types of biological profile.

Animals↗
PubMed1983

An inexpensive microcomputer system for analysis of single channel currents.

A description is given of a system for rapidly measuring the durations of open times and closed times of single channel currents obtained by patch clamp techniques. The apparatus required, a BBC microcomputer and a Unilab interface, is inexpensive and easy to use. An outline of the software is given and measurements of the accuracy of timings presented. Examples of analyses of single channel currents obtained from spinal neurones in cultures are also presented.

Animals↗
PubMed1984

An 8-channel neuron recording interface for a microcomputer (Apple II), designed to gather spike occurrence times.

A microcomputer interface card is described, using a standard peripheral interface adapter chip, for use in multi-channel extracellular single unit recording. The design is for the Apple II. The card sends an interrupt signal to the processor whenever a pulse arrives to it, and enables the computer to read out which of 8 possible channels brought the pulse and when.

Analog-Digital Conversion↗
PubMed1984

A program for computing power spectra on a microcomputer.

A computer program is presented that will calculate Fourier transforms and power spectra. The program is written in assembly language for the Z-80 microprocessor and has been used on a Radio Shack TRS-80 microcomputer to analyze time-dependent data from laboratory experiments.

Animals↗
PubMed1985

Signal averaging by microcomputer using a program written in a high-level language.

A program, written in the language Pascal, is described for signal averaging with a microcomputer. The program instructs the computer to acquire data from two channels on-line. For up to 3 channels of extracellular or intracellular recording analysed simultaneously, it was found not to be necessary to employ machine code or an assembler to provide adequate temporal resolution.

Action Potentials↗
PubMed1985

Some neurobiological applications of the BBC Model B microcomputer and Unilab 8-bit interface.

Four computer programs written for the BBC Model B microcomputer (coupled to a Unilab 8-bit interface) are discussed. These programs enable the system to be used as (1) a transient recorder, (2) a rapid signal averager, (3) a spike-train analyser and (4) an instrument for measuring the amplitude of single channel currents. Flow-charts illustrating the operation of each program are given along with a detailed discussion of how the programs may be used in the laboratory. The discussion is illustrated using recordings taken from experiments conducted on a range of neurobiological preparations.

Animals↗
PubMed1985

Implementation of a movement paradigm using the Commodore 64 microcomputer.

Implementation of an alternating movement paradigm for monkeys was achieved using an inexpensive but versatile microcomputer, the Commodore 64. During task performance, the computer monitors one of three user selectable input signals (e.g. joint position) and continuously displays this signal as a moving cursor on a video monitor along with a user positioned target box. Other user defined parameters include in-target holding time and reinforcement ratio. The system also provides two sound cues to signal entry of the cursor into the target box and successful completion of a trial. Extensive use is made of the computer's intrinsic hardware features for implementation of movement paradigm functions. Use of external components is limited to digitizing and interface hardware. A two part software package consisting of a BASIC and a machine language program performs all task and hardware related functions. Acquisition and display of analog input signals, display of target positions, and delivery of auditory cues and applesauce rewards are all controlled by the machine language program. All user defined parameters are specified from the BASIC menu program. The specific programs described in this paper should be applicable to the control of tasks requiring alternation of a behavioral parameter between two target zones.

Animals↗
PubMed1985

Microcomputer-assisted densitometer for quantitative receptor autoradiography.

We describe here a simple, inexpensive microcomputer-assisted densitometer for use with quantitative receptor autoradiography. The resolution of this system is approximately 100 micron. With this system, and an accompanying program DENSIT, it is relatively easy to convert density values of autoradiograms into molar quantities of bound ligand. The general design of the system and the logic of the DENSIT program are applicable to a variety of hardware systems.

Animals↗
PubMed1986

An inexpensive microcomputer digital imaging system for densitometry: quantitative autoradiography of insulin receptors with 125I and LKB Ultrofilm.

This article describes a video digitizing system designed for measuring film optical density. The system, which is based on a 6-bit (64 gray level) digitizer, solid state video camera, and Apple II microcomputer, digitizes a rectangular area selected by the operator and converts the gray level values into preselected standard units. In order to develop autoradiographic standard curves for quantitative autoradiography with 125I-insulin, liver slices labeled with 125I-insulin and plastic sections containing known amounts of tritium were apposed to the same sheet of LKB Ultrofilm for exposures of 1-7 days. The results indicate that 3H plastic standards can be used to calibrate QAR of 125I-labeled ligands with LKB Ultrofilm. The Apple system was also used to measure binding of 125I-insulin to the external plexiform layer (EPL) in slices of the rat olfactory bulb. Results suggest that the EPL has two binding sites for insulin, a high affinity site with Kd = 1.0 X 10(-8) M and a low affinity site having a Kd = 1.4 X 10(-5) M.

Animals↗
PubMed1986

A distributed microcomputer-controlled system for data acquisition and power spectral analysis of EEG.

A relatively powerful and inexpensive microcomputer-based system for the spectral analysis of the EEG is presented. High resolution and speed is achieved with the use of recently available large-scale integrated circuit technology with enhanced functionality (INTEL Math co-processors 8087) which can perform transcendental functions rapidly. The versatility of the system is achieved with a hardware organization that has distributed data acquisition capability performed by the use of a microprocessor-based analog to digital converter with large resident memory (Cyborg ISAAC-2000). Compiled BASIC programs and assembly language subroutines perform on-line or off-line the fast Fourier transform and spectral analysis of the EEG which is stored as soft as well as hard copy. Some results obtained from test application of the entire system in animal studies are presented.

Animals↗
PubMed1987

A microcomputer-controlled response measurement and analysis system for insect olfactory receptor neurons.

A microcomputer system has been built to stimulate, record, and analyze responses from peripheral insect olfactory receptor neurons. Software has been developed to sort action potentials (spikes) in extracellular records obtained from multi-innervated antennal sensilla, and perform frequency, interspike interval, distributional, and regression analyses on responses in groups of records. The olfactory stimuli can be presented in different patterns, and plots or histograms of analyses, spike records, and individual spikes can be displayed in different formats and hard-copied during a recording session. This report describes the main features of the system and discusses the methods used for sorting spikes, performing analyses, and managing records and analyses in a database. Examples are given of renewal density analyses for 4 classes of peripheral receptor neuron in records from 2 types of olfactory sensillum on the antenna of the cabbage looper moth, Trichoplusia ni (Hübner).

Action Potentials↗