scientific equipment, namely, biomedical research instruments and associated apparatus used in the field of physiology, pharmacology, and toxicology, namely, video integrators for measuring change in dimensions of isolated research animal organs in vitro and in vivo, automated perfused blood vessel measurement devices and automated animal heart perfusion devices for measuring responses to chemical, electrical and photosensitive stimuli in research animals, constant pressure respirators and respiratory transducers for other than artificial respiration in research animals, data acquisition software for animal heart organ and muscle data, rat and mouse tail blood pressure data, and respiration data from restrained and unrestrained animals, pressure controlled ventilator for other than artificial respiration of research animals, isolated lung perfusion data acquisition and control devices for measuring responses to chemical, electrical and photosensitive stimuli in isolated animal organs in vitro and in vivo, motorized transducer positioners for measuring the force going through the blood vessels of research animals to enable precise adjustment, constant pressure respirators for artificial respiration and free breathing animals for use in animal research, respirator transducer for artificial respiration for measuring respiratory responses in research animals that are either free breathing or artificially respirated, systolic blood pressure and heart rate monitors for use in animal research, cardiac and medical rigid and flexible electrodes for animals for use in animal research