RESUMO
Carotid plaques are closely related to strokes or transient ischemic attacks.MRI plays an important role in the diagnosis and evaluation of prognosis.At present,the study of carotid plaque MRI is mainly focused on the evaluation of plaque stability and pathological mechanism.The research progresses of development mechanism and MR techniques in the diagnosis of carotid plaque were reviewed in this article.
RESUMO
Carotid plaques are closely related to strokes or transient ischemic attacks.MRI plays an important role in the diagnosis and evaluation of prognosis.At present,the study of carotid plaque MRI is mainly focused on the evaluation of plaque stability and pathological mechanism.The research progresses of development mechanism and MR techniques in the diagnosis of carotid plaque were reviewed in this article.
RESUMO
Objective To investigate the dose and mechanical properties of medical electron linear accelerators in grass-roots radiotherapy units in Sichuan Province,China via sampling and inspection.Methods A total of eight radiotherapy units in Sichuan Province were selected by sampling,and the tests were performed for the dose and mechanical properties of the medical electron linear accelerators in use.Among these accelerators,there were 5 imported accelerators and 3 domestic accelerators.The test items and methods were determined according to the requirements in GB15213-94.Results Among the 14 test items,the items related to the flatness,symmetry,and overlap of radiation field.The other tests of dose accuracy and mechanical precision achieved good results.Conclusions There is a need to strengthen the daily quality control work for dose and mechanical accuracy of medical electron linear accelerators in grass-roots radiotherapy units in Sichuan Province and perfect the allocation of professional equipment and personnel and training of related personnel.With the support of Sichuan Radiotherapy Quality Control Center,quality control supervision and guidance should cover the whole province.