ABSTRACT
Objective To develop a reasonable plan of monitoring personal internal exposure dose. Methods This paper introduced the methods of monitoring the individual dose and direct measurement of three representative radionuclides. Results The maximum monitoring periods were determined according to the radionuclide retention characteristics and the reporting standards and requirements, which were m(1)/m(T/2) ≤ 3 and m(T/2)/m(T) ≤ 3. The lower detection limit of the instrument was derived from the monitoring periods and the annual radionuclide intake limit, which should be lower than the derived method detection limit of the corresponding radionuclide. Then the measuring duration of the instrument that meets the corresponding conditions was derived from the derived method detection limit of the instrument and the maximum monitoring period. Conclusion Our results provide a reference for the formulation of a plan of monitoring personal internal exposure dose.
ABSTRACT
New registry classifications of chemical drugs redefined the concepts of new drugs and generic drugs. New drugs emphasize the international innovation including innovate new drugs and modified new drugs. Modified new drugs are improvement of drugs already on the market to achieve superior efficacy. With the advantages of high success rate,high return,low risk and long life cycle,modified new drugs have become the mainstream of new drugs research and development in the world. Modified new drugs R&D in China should be based on clinical demand and focused on the differentiation research in order to obtain new preparations with signif-icant clinical advantages to better serve the clinical practise. This paper states the concept and characteristics of modified new drugs in China,makes case analysis and shares the development history of blockbuster modified new drugs in the world,clarifies the opportuni-ties and challenges and provides ideas for the future development of modified new drugs in China.