A protein connection assay is an analytic method to measure corticosteroids, cortisone, progesterone, testosterone and thyroxine.

A proton is a basic particle located in the nucleus of an atom. The number of protons in the nucleus governs the chemical properties of that element. The positive electrical charge is equal to the negative charge of an electron and the mass is similar to that of a neutron (see also baryon). The proton belongs to the group of hadrons and is composed out of three quarks.
A hydrogen (H1) nucleus is build of one proton.
Proton beam therapy is the preferred treatment for cancers near the eye and the spinal cord.

The pulmonary perfusion scintigraphy records the distribution of pulmonary arterial blood flow. The most common indication for lung scintigraphy is the detection of pulmonary embolism. The most widely used radiopharmaceuticals are technetium-99m MAA (macroaggregates of albumin) or 99mTc-HAM. Other radiopharmaceuticals include sulphur colloid macroaggregated albumin, radioactive albumin microspheres and albumin labeled with I-131, or I-113m.
Perfusion imaging of the bronchopulmonary system is based on the principle of capillary blockade. The perfusion study is accomplished by injecting 40 to 160 MBq (1-4 mCi) of the radiopharmaceutical and during repeated deep inhalation. The aggregates are extracted during their first pass through the lung, thus imaging can begin immediately. Pulmonary perfusion scintigraphy is particularly useful in combination with gas ventilation scintigraphy and aerosol ventilation scintigraphy.

See also Inhalation Scintigraphy.

The basis of pulmonary scintigraphy is the detection of gamma rays emitted from the lung after administration of a radioactive tracer.
See Lung Scintigraphy.

See also Aerosol Ventilation Scintigraphy, Gas Ventilation Scintigraphy, Pulmonary Perfusion Scintigraphy, Computed Tomography Pulmonary Angiography and Lung Imaging.

A pulse oximeter is a medical device that displays a digital percentage readout of a calculated value of the hemoglobin that is saturated with oxygen (SpO2).