But that is his experience! Once you learn how to replace a smoke alarm, a carbon monoxide detector should be next. My recommendation: buy a good plug-in detector! If you want, get one with a battery back up. Put it near any potential CO source and another near your bedroom(s). And you will be safe and feel safe.
The most commonly used MRI contrast agent is the element gadolinium. As with radiographic agents, gadolinium can be injected into the blood vessels or injected into a joint. Gadolinium-enhanced MRI scans can be very helpful at showing subtle findings such as labral tears in the shoulder and hip cartilage damage.
Helium-3 is a very rare helium isotope, and you can do MRI/NMR of it. But that is not what happens in typical MRI of humans, as they don't contain any measurable amount of helium-3 (though there seem to be more exotic experiments that use it).he vast majority of helium used in MRI is for cooling, not as an imaging nuclei, to the point that I wasn't aware it was even used in that manner (but if Wikipedia says it, it must be true). The vast majority of helium on the planet is $He^4$, not $He^3$. â Colin McFaul Dec 11 '12 at 16:35.