Trimethoprim molecularly imprinted polymer (MIP) was prepared as the coating of stir bar sorptive extraction (SBSE) and applied to the trace analysis of trimethoprim and three sulfonamides in complex samples.The MIP-coating was about 21.5 μm thickness with the relative standard deviations (RSD) of 5.9％ (n=10).It was homogeneous and dense with good thermal and chemical stability.The extraction capability of the MIP-coating was 1.7 times over that of the non imprinted polymer (NIP) coating.The MIP coating exhibited selective adsorption ability to sulfonamides,triazines and methotrexate besides antibacterial synergists.The methods for the determination of trimethoprim and three sulfonamides by MIP-coated stir bar sorptive extraction coupled with HPLC were developed.It was successfully applied to the trace trimethoprim analysis in spiked urine and plasma samples.The linear range was 5 to 200 μg/L and the detection limit was 1.6 μg/L.The recoveries in urine and plasma samples were 84.5％ to 91.7％ with RSDs of 2.9％ -4.4％,71.9％ to 85.1％ with RSDs of 3.0％ -7.3％,respectively.The trimethoprim MIP-coated stir bar was also applied to the trace sulfonamides analysis in spiked milk sample.The linear range was 10-200 μg/L,the detection limit was within the range of 4.5-6.1 μg/L,and the recovery was 83.2％ - 110.2％ with RSDs of 4.1％ -8.0％.

Objective To investigate the effect of blood flow restriction combined with low-intensity plyometric jump training(LI-PJT+BFR)on lower limb dynamic postural control of functional ankle instability(FAI)in college students. Methods From March to May,2023,40 FAI college students were recruited from Xi'an Physical Education University,and randomly divided into high-intensity plyometric jump training(HI-PJT,n = 14)group,low-intensity plyomet-ric jump training(LI-PJT,n = 13)group and LI-PJT+BFR group(n = 13).All the groups finished the six-week corresponding training.The maximum voluntary isometric contraction(MVIC)of tibialis anterior,peroneus lon-gus,lateral head of gastrocnemius,gluteus maximus,vastus lateralis,biceps femoris and semitendinosus were measured,and the root mean square(RMS)of electromyography of these muscles was measured during the sin-gle-leg landing(SLL),using wireless surface electromyography before and after intervention.Moreover,they were assessed with Y-balance test and Cumberland Ankle Instability Tool(CAIT). Results MVIC and RMS of the target muscles improved after intervention in all the groups(t>2.218,P<0.05),except MVIC and RMS of peroneus longus,gluteus maximus,biceps femoris and semitendinosus in LI-PJT group,and RMS of peroneus longus in LI-PJT+BFR group;and MVIC and RMS of the target muscles were the least in LI-PJT group(F>3.262,P<0.05),except those of peroneus longus.The extension scores of Y-balance test and the total score improved after intervention(t>2.485,P<0.05),and they were the least in LI-PJT group(F>5.042,P<0.05).The CAIT score improved after intervention(t>5.227,P<0.001),and it was the least in LI-PJT group(F = 4.640,P<0.05). Conclusion LI-PJT+BFR could improve lower limb dynamic postural control of FAI college students,which is similar to HI-PJT.