Of the first 83 elements in the periodic table, 80 have isotopes considered to be stable. Technetium, promethium (atomic numbers 43 and 61, respectively) and all the elements with an atomic number over 82 only have isotopes that are known to decompose through radioactive decay.nly 13 of the 38 known-but-unstable elements (assuming the total number of elements is 118) have isotopes with a half-life of at least 100 years. Every known isotope of the remaining 25 elements is highly radioactive; these are used in academic research and sometimes in industry and medicine.
Cortisol Saliva Test. This test uses a saliva sample to measure a personâs Cortisol level. Saliva testing can provide just as accurate a measurement of adrenal hormones like Cortisol as a blood test can.
If the adrenal glands are functioning normally, then cortisol levels will rise with the ACTH stimulation. If they are damaged or not functioning properly, then the cortisol level will be low. A longer version of this test (1-3 days) may be performed to help distinguish between adrenal and pituitary insufficiency. cortisol test may be ordered when a person has symptoms that suggest a high level of cortisol and Cushing syndrome, such as. 1  High blood pressure (hypertension). 2  High blood sugar (glucose). 3  Obesity, especially in the trunk. 4  Fragile skin. 5  Purple streaks on the abdomen. 6  Muscle wasting and weakness.