Abstract: An apparatus for delivering and receiving gas to and from a patient, such as for lung ventilation studies. In accordance with the invention there is provided a restrictive breathing chamber adapted for coupling to the patient's breathing organs. A system, including a first check valve, is provided for coupling the breathing chamber to an inflatable gas receptacle so as to allow flow only toward the inflatable gas receptacle. Active gas input apparatus, including a second check valve, is also coupled to the breathing chamber, the second check valve allowing flow only toward the breathing chamber means. First and second auxiliary tubes and a gas filter are also provided. A system is provided for coupling the first auxiliary tube from the inflatable receptacle through the gas filter and to an ambient air environment. The second auxiliary tube is coupled from the inflatable receptacle to an ambient air environment.

Abstract: The invention is a system for transporting, storing, and injecting of radioactive isotopes, the system including a unit dose of radioactive isotope-containing fluid loaded in a disposable shielded syringe. There is provided a syringe body including a barrel and a plunger slideable in the barrel and extending from the rear of the barrel for manual actuation. A body of radiation-shielding material substantially covers the barrel, the body having a slot therein. A radiation-shielding unit is removably mounted over the slot. An aliquot of radioisotope-containing fluid is contained within the barrel. In the preferred embodiment of the invention, an optically-transparent radiation-shielding member is adapted for removable insertion over the slot. Before use of the syringe, the radiation-shielding unit, which provides protective shielding over the slot during shipping and storage, is removed and replaced by the optically transparent radiation-shielding member through which the user can view the syringe contents.