Objective To investigate the application of proton magnetic resonance spectroscopy (1H-MRS) in patients with white matter lesions (WMLs).Methods Patients with WML were enrolled.According to imaging and clinical symptoms,they were divided into either a subcortical atherosclerotic encephalopathy (SAE) group or a simple leukoaraiosis (LA) group.All patients completed the examinations of MRI,1H-MRS,and auditory event-related potential P300.Multi-voxel 1H-MRS acquisition range was lateral periventricular white matter region.N-acetyl aspartic acid (N-acetylaspartate,NAA),creatinine (Cr),choline (Cho),NAA/Cr,and P300 latency and amplitude were documented.Results A total of 50 patients with WML were enrolled,including 30 patients with SAE and 20 with simple LA.NAA (median,quartile interval; M,IQR) (0.732 [0.680-0.804] vs.0.915 [0.866-0.963] ; Z =5.634,P ＜ 0.001) and NAA/Cr(M,IQR)(1.533 [1.317-1.817] vs.2.003 [1.794-2.387];Z=-3.921,P＜0.001) intheSAE group were significantly lower than those in the simple LA group.The htency of P300 (M,IQR) in the SAE group was significantly bnger than that in the LA group (370.50 [363.50-385.25] msvs.351.50 [342.75-359.00] ms; Z =-4.382,P ＜ 0.001),and the amplitude (M,IQR) was significantly lower than that in the simple LA group (4.35 [2.90-7.20] mVvs.6.95 [5.93-9.10] mV; Z=-2.942,P=0.003).Conclusions 1H-MRS can be used to identify the patients with SAE and simple LA,and provide an objective basis for the prevention of progress from LA to SAE.

OBJECTIVE:To determine the content of levofloxacin by PVC membrane selective electrode. METHODS: A glass electrode coated with levofloxacin PVC membrane was prepared for the first time with the molecular complex of levofloxacin iodide and bismuth iodide as electric active material, and a series study was performed on its responsibility. RESULTS: The electrode gave Nernst response to levofloxacin over the concentration range of 5.0?10-3～1.0?10-5 moL?L-1 with a slope rate of 56.5mV?pC-1, a suitable pH of 2.5～4.0, and an average recovery rate of 98.31%～101.6%(2.80%～4.90%). CONCLUSION: The electrode was simple in operation, and it has a rapid response and good reproducibility, and it is applicable for the quantitative determination of levofloxacin.