有效半减期(effective half life)指生物体内的放射性核素由于从体内排出和物理衰变两个因素作用,减少至原有放射性活度的一半所需的时间(Teff ) 临床最常用的肿瘤非特异性显像剂 201Tl与99mTc-MIBI 67Ga 脑血流灌注显像剂有哪几种 99mTc-ECD(99mTc-双胱乙酯)或99mTc-HMPAO(99Tcm-六甲基丙烯胺肟) ...
The half-life of ~(99m)Tc in various chemical conditions has been measured precisely. The ~(99m)Tc was produced by the reaction of ~(100)Mo(γ, n)~(99)Mo, followed by disintegration to ~(99m)Tc. The half-life of ~(99m)Tc was determined within the good precision of the ...
Tc-99m TECHNETIUM-99m [99m Tc]PHYSICAL DATA • Gamma Energy: 141 keV (89%)21 keV (1%)18 keV (6%)• Beta Energy: no betas • Alpha Energy: no alphas • Physical Half-Life: 6 hours • Biological Half-Life: 24 hours* • Effective Half-Life:...
Tc-99m's half life of 6.0058 hours is considerably longer (by 14 orders of magnitude, at least) than most nuclear isomers, though not unique. This is still a short half-life relative to many other known modes of radioactive decay, and it is in the middle of the range of...
The Tc-99m RBC method was first described in 1979. The major advantage over Tc-99 sulfur colloid is that imagescan be acquired for a longer length of time, limited only by the physical half-life of Tc-99m and the stability of the radiolabel, thus usually up to 24 hours....
Table 5: Physical Decay Chart; Tc 99m Half-Life 6.02 Hours Hours Fraction Remaining Hours Fraction Remaining 0* 1.000 7 0.447 1 0.891 8 0.398 2 0.794 9 0.355 3 0.708 10 0.316 4 0.631 11 0.282 5 0.562 12 0.251 6 0.501 * Calibration Time 12. Technetium TC 99M Sestamibi ...
In conclusion, 99Tcm HMPAO seems to be a promising platelet label for imaging thrombotic lesions but not for platelet-survival studies because of the short physical half-life of 99Tcm. 展开 DOI: 10.1097/00006231-198810000-00024 被引量: 7 ...
半衰期Technetium Tc 99m decays by isomeric transition with a physical half-life of 6.02 hours. 清除Following intravenous administration in normal subjects, Technetium Tc 99m Mebrofenin was rapidly cleared from the circulation. ATC代码V09DA04
Following intravenous administration, Technetium Tc 99m Sulfur Colloid Injection is rapidly cleared from the blood by the reticuloendothelial system with a nominal half-life of approximately 2 1/2 minutes. Uptake of the radioactive colloid by organs of the RES is dependent upon both their relative...
Tc-99m, has a specific activity which is almost nine orders of magnitude lower and a half life which is roughly eight orders of magnitude longer. For the organism being studied or diagnosed the slow rate of decay from the relatively stable low specific activity Tc-99 to its degradation produ...