OBJECTIVE:To determine the concentration of dehydroisoandrosterone sulfate (DHEAS) in human plasma by LC-MS.METHODS:With estrogen sulfate (ES) served as an internal standard,the plasma samples were deproteinized with acetonitrile,extracted by solid phase,hydrolyzed and derivatized.Then the concentration of DHEAS was determined by HPLC-MSD on Agilent SB C18 with column temperature kept at 40℃.The mobile phase consisted of acetonitrile-water (in gradient elution).Atmosphere pressure chemical ion source in negative ion detection model was employed.The ions selected for SIM (selected ion monitoring) quantitative analysis included m/z 490.0 (DHEAS ) and m/z 472.1(ES)[M-H]-.RESULTS:The linear range of DHEAS was 250.0～320.0 ng?mL-1(r=0.999 4).The extraction recovery of the simulated human albumin samples ranged from 71.1%～78.9% and its relative recovery ranged from 98.3%～101.4%.Both the intra-day RSD and inter-day RSD were less than 10%.The mean concentration of DHEAS in 15 health aged male volunteers was (981.6?353.4) ng?mL-1.CONCLUSION:The method is simple,practical,accurate and sensitive,and it is applicable for the determination of plasma concentration of DHEAS.

Objective To evaluate the embolic effect on rabbits arteries using self-made copper plated platinum coil.Methods 1 7 New Zealand Big Ear Rabbits were selected.Unilateral subclavian artery or carotid artery was embolized with self-made secondary level copper plated platinum micro-coils (experimental group)through 3F-catheter.Contralateral subclavian artery or carotid artery was also embolized using secondary level platinum micro-coils (control group)as a control.The level of serum copper ions and the liver and renal function were recorded during different intervals before and after embolization.The arteriography and the tissue his-tology were observed respectively during different intervals after the embolization.Results 1 5 of 1 7 rabbits were embolized success-fully.After embolization,the level of serum copper ions increased in 2 weeks(P <0.05).However,it returned to preoperative level after 4 weeks (P >0.05).The liver and renal function was similar to that of the preoperation after 2 weeks.After embolization,an-giography showed that vascular embolization effect between two groups was not significantly different at 10 min and 30 min;howev-er,the embolization effect of experimental group was superior to that of control one (P <0.01)at 3 days and 1 week,2 weeks,4 weeks,6 weeks and 12 weeks.Pathological results showed that there were a lot of thromboses inside,outside and around the copper coil.Few thromboses appeared around platinum coil in control group.The thrombosis situation in experiment group was better than that in control one (P <0.01).However,no significant difference in inflammatory cell infiltration between two groups was found. Conclusion Self-made secondary level copper plated platinum coil has good physical property,rememorability,flexibility and con-trollability.

With the increasingly strengthening of economic globalization and higher education internationalization,medical imageology as an important intersecting science in life sciences has more and more international communion and cooperation.In China many hospitals and medical colleges require large quantities of medical imageology professionals,and it is very necessary and important to develop the bilingual education in medical imageology,though a series of problems appear in the process.

The developing situation of "big image" makes the medical imaging become an increasingly huge and complicated system.It offers higher request to the medical imaging teaching.The internship of last term is always influenced by attending the graduate student's entrance examination and looking for job,the effect of teaching can't be assured,and it especially important to do well in field trip,thus it can reduce or avoid the phenomenon of "practice after graduate".

With development of medical imaging,especial the wide application of CT,MRI and so on,traditional education method can not meet the needs of the intern-clinical students.Fairly satisfying teaching effects has been achieved for the effective combination of traditional teaching methods with net-work educational method.

With development of medical imaging,traditional picture has been replaced by digital information.To apply information-based education to medical imaging and enhance the teaching quality,the article explored the teaching methods of information-based education.