论文部分内容阅读
最近报道了又一种优良的~(99m)Tc标记肝胆放射性药物——~(99m)Tc(Sn)-N-吡哆-5-甲基色氨酸(Tc-PHMT)。在这类药物日益增多的现阶段,有必要提及有关优质放射性药物的若干问题:完善的放射性药物的特性是什么?这些特性如何体现?肝胆显像剂有哪些主要进展?新报道的Fc-PHMT与其它已发展的药物相比,又如何? 一般说来,理想的放射性药物应快速通过有关的生理或病理生理途径,而不被其它途径清除。这样的放射性药物在有关途径中取得最高计数。放射性药物最初的生物学分布依赖于清除率或流量与摄取效率之积。既然流量不受放射性药物支配,如果有关途径的攝取效率接近100%,而其它途径摄取效率接近0%时,将得到最大清除率。如果有关途径包含超出最初
Recently, another excellent (99m) Tc labeled hepatobiliary radiopharmaceutical, 99mTc (Sn) -N-pyridoxine-5-methyltryptophan (Tc-PHMT) has been reported. At this stage of the growing number of these drugs, it is necessary to mention a few questions about quality radiopharmaceuticals: What are the characteristics of a well-established radiopharmaceutical and how are these characteristics reflected? What are the major advances in hepatobiliary imaging? The newly reported Fc- What about PHMT versus other developed drugs? In general, the ideal radiopharmaceutical should pass quickly through the relevant physiological or pathophysiological pathways without being cleared by other pathways. Such radiopharmaceuticals achieve the highest counts in the relevant pathways. The initial biological distribution of the radiopharmaceutical depends on the clearance or the product of the flux and the efficiency of the uptake. Since traffic is not dominated by radiopharmaceuticals, maximum clearance will be achieved if the pathway’s uptake efficiency is close to 100%, while the other pathway uptake efficiencies are close to 0%. If the path involved is beyond the original