Objective To investigate the imaging manifestations and pathogenesis of liver focal nodular hyperplasia-like(FNH-like)lesions in patients undergoing antineoplastic chemotherapy.Methods The clinical and imaging data of focal nodular hyperplasia(FNH)and FNH-like lesions patients confirmed by pathology after antineoplastic chemotherapy were analyzed retrospectively.Results A total of 67 FNH-like nodules were detected in 15 patients after antineoplastic chemotherapy,including multiple FNH nodules in 8 cases and sin-gle nodule in 7 cases.The mean detected time of FNH-like nodules was(18.9±11.7)months.Central scarring could be observed during follow-up in 5 nodules,and the rest showed atypical FNH features.Among 45 nodules examined with hepatocyte-specific con-trast medium,36 nodules showed slightly high signal in the hepatobiliary phase and other 9 nodules showed isosignal.Conclusion FNH-like lesions in patients during antineoplastic chemotherapy have certain imaging features,such as lack of central scarring,gener-ally smaller nodules,delayed enhancement,and hyperenhancement in hepatobiliary-specific phase,which are of significant value in the diagnosis and differential diagnosis of the disease.

Objective To analyze the imported measles cases who came to Beijing seeking for better medical services and to explore the feasible strategies for prevention and control of the situation.Methods Descriptive analysis was conducted for all the measles cases noted from the Measles Surveillance System,between January 1,2014 and December 31,2014.Results 3 328 measles cases were reported in Beijing,including 2 397 (2 397/3 328,72.0％) native residents and 931 (931/3 328,28.0％) came from other provinces.Peak of the imported cases appeared earlier than those native cases,with 934 cases (934/2 397,39.0％) having had hospital exposure 7-21 days prior to the onset of the disease.Majority of the imported were children,including 718 of them (718/931,77.1％) under the age of 15.Most cases were reported from 3 infectious disease hospitals (567/1 156 person-time,49.0％) and 2 children' s hospitals (445/1 156 person-time,38.5％).Original addresses of the imported cases distributed in 24 provinces,with 705 of them (705/931,75.7％) coming from Beijing' s neighboring province (Hebei).Clinic symptoms with epidemiological information were analyzed on 712 cases.704 cases (704/712,98.9％) presented rash at home town while another 621 cases(621/712,87.2％) developed rash 4 days after arriving in Beijing and were still in the infectious period.Conclusion There was a big amount of imported measles cases in Beijing that called for the elimination of the disease in a urgent phase.It is necessary to timely develop and conduct targeted prevention and control measures on the disease in Beijing.

Objective To compare image quality of 3.0T and 5.0T MR cholangiopancreatography(MRCP).Methods Eighteen patients with bile duct dilation(bile duct dilation group)and 7 healthy volunteers(healthy group)were prospectively enrolled.MRCP was performed with 3.0T and 5.0T scanners,respectively,and the ability for displaying details of bile duct tree,signal-to-noise ratio(SNR)and image artifacts were compared between 3.0T and 5.0T MRCP.Results In bile duct dilation group,the number of branches,total branch length and the maximum branch length of bile duct tree on 5.0T MRCP were all greater than those on 3.0T MRCP(all P＜0.05).In healthy group,the number of branches and total branch length of bile duct tree on 5.0T MRCP were both greater than those on 3.0T MRCP(both P＜0.05).In both groups,the SNR of 5.0T MRCP was greater than that of 3.0T MRCP,but the difference was not significant(both P＞0.05).No significant difference of image artifacts was found between 3.0T and 5.0T MRCP(P=0.054).Conclusion 5.0T MRCP might display better anatomical details of bile duct tree than 3.0T MRCP,with SNR and image artifacts comparable to 3.0T MRCP.

Objective To compare image quality of 5.0T and 3.0T time of flight MR angiography(TOF-MRA)and displaying choroidal anterior arteries(AChA).Methods Data of 80 patients who underwent head 5.0T(5.0T group,n=40)and/or 3.0T TOF-MRA(3.0T group,n=42)were retrospectively analyzed,among them 2 patients underwent both 5.0T and 3.0T TOF-MRA.The subjective scoring and objective evaluation of image quality were performed,and the results were compared between groups.AChA was divided into proximal,intermediate and distal segments(A1,A2,A3 segment),the quantity of left and right AChA shown on 5.0T and 3.0T TOF-MRA were recorded,and the length and diameter of left and right AChA dispalyed on MRA were comparatively observed.Results The subjective scores of image quality of 5.0T group were higher than that of 3.0T group(5.0[4.0,5.0]vs.5.0[3.0,5.0],Z=6.417,P=0.029).The signal-to-noise ratio(91.01±5.04)and contrast-to-noise ratio(72.47±5.14)of 5.0T group were both larger than those of 3.0T group([62.11±4.16],[48.92±4.62],t=28.339,19.681,both P＜0.001).There were 80 segments of AChA-A1,80 of AChA-A2 and 60 segments of AChA-A3 displayed on 5.0T TOF-MRA,while 60 segments of AChA-A1,36 of AChA-A2 and 12 segments of AChA-A3 displayed on 3.0T TOF-MRA,respectively.In 5.0T group,the length of the left and right AChA was(24.01±7.41)mm and(22.72±9.36)mm,with diameter of(1.16±0.12)mm and(1.19±0.14)mm,respectively,whereas in 3.0T group,the relative values were(18.35±8.67)mm,(16.80±6.94)mm,(0.99±0.25)mm and(0.95±0.29)mm,respectively,all in 5.0T group were greater than in 3.0T group(t=3.242,3.183,4.595,3.846,all P＜0.001).Conclusion Compared with 3.0T TOF-MRA,5.0T TOF-MRA of AChA might provide better image quality and clearer vessel depiction,being helpful to clinical diagnosis and treatment of ACHA-related cerebral vascular diseases.

Objective To evaluate the safety and epidemiological effects on the first mass vaccination program, using the China-made A (H1N1) influenza vaccine. Methods Descriptive epidemiology and cohort study design were used to assess the influenza A H1N1 vaccine on its safety and epidemiological effects. Results 95 244 subjects were immunized with A (H1N1) influenza vaccine. 193 adverse events were reported through AEFI Management System, with the Reported rates after immunization was carried out. Of 81 adverse reactions confirmed to be related to immunization,reported through the AEFI Management System. The epidemiological protection rate of A (H1N1)influenza vaccine showed a similar safety profile to seasonal flu vaccine. The vaccine demonstrated a good epidemiological effects against A (H1N1) influenza virus infection.

Objective To observe the value of 5.0T MRI in measuring the volumes of hippocampal formation(HF)subfields in healthy adults.Methods Cranial high-resolution TIWI were prospectively obtained in 23 healthy adult volunteers using 5.0T and 3.0T MR scanners,respectively.HF was divided into 38 subfields,and then the volume of each subfield was measured using FreeSurfer software.The volumes of HF subfield based on 5.0T and 3.0T MR T1WI were compared,and the correlations of the outcomes were analyzed.Results Significant differences of the volumes of bilateral hippocampal tails,left parasubiculum,left molecular layer of hippocampal head,left granular cell-molecular layer-dentate gyrus head,right granular cell-molecular layer-dentate gyrus body,left cornu Ammonis(CA)1 head,left CA3 head,left CA4 head,right fimbria of hippocampus and left hippocampus amygdala transition area were found between 5.0T and 3.0T T1WI(all P＜0.05).The volumes of HF subfields measured based on 5.0T and 3.0T T1WI were moderately to highly positively correlated(all r＞0.5,all P＜0.01).Conclusion 5.0T MRI could be used to measure the volume of HF subfield in adults.