| 摘要 |
<p>The invention relates to the use as a contrast agent in MR imaging of a physiologically tolerable lanthanide compound or salt thereof having first and second oxidation states which differ in relaxivity by a factor of at least 5, and which is convertible in vivo from said first to said second oxidation state whereby contrast is enhanced in a body region in which conversion to said second state does or does not occur.</p> |
