Objective To investigate the feasibility and accuracy of enhanced magnetic resonance pulmonary perfusion imaging(MRPP) in the diagnosis and follow-up of pulmonary embolism(PE). Methods Sixty patients suspected of PE underwent MRPP. Twenty-seven patients also underwent radionuclide perfusion imaging. 22 patients repeated MRPP examination after 3 day to 1 month anticoagulation or thrombolytic therapy. The feasibility and accuracy of MRPP in the diagnosis and follow-up of PE were evaluated according to the transformation rate of signal (TROS), time-signal curve and some parameters of main pulmonary artery(such as peak value of flow,mean flow velocity and flow rate). The t test and rank sum test were used for the statistics. Results MRPP showed a high agreement with radionuclide perfusion imaging. TROS was (2. 86 ± 2. 48 ) vs ( 6. 72 ± 2. 54) ( t = 3. 370, P ＜ 0. 01 ), the peak time was ( 13.98 ±5.60) vs ( 12. 33 ± 3.63 ) s ( t = 3. 930, P ＜ 0. 01 ), the peak value of main pulmonary blood flow was (60.39 ± 15. 17) vs (69.93±13.22) cm/s(t=2.930, P＜0. 01) and mean flow velocity (11.68±5.46) vs ( 13.54 ± 4. 18 ) cm/s ( t = 2. 380, P ＜ 0. 05 ) before and after anticoagulation or thrombolytic therapy. The flow rate per unit was (80. 57 ± 24. 87) vs ( 85.48 ± 11.81 ) ml/s ( t = 0. 86,P ＞ 0. 05 ) . Conclusion MRPP shows a high agreement with radionuclide perfusion imaging and is a useful method for the diagnosis and follow-up of PE.

Objective To investigate the efficacy of interferon α(IFNα)and adefovir dipivoxil (ADV)combination therapy in HBeAg positive chronic hepatitis B(CHB)patients and to explore the optimized strategy for individualized treatment.Methods A total of 156 HBeAg positive CHB patients were enrolled in the study from January 2005 to June 2009 in the Third Affiliated Hospital of Hebei Medical University.Fifty-six CHB patients with hepatitis B virus(HBV)DNA≥1 X 107copy/mLand/or liver fibrosis stage≥S3,or previous monotherapy failure(relapse)were treated with initial IFNα and ADV combination therapy.Fifty-two patients who didn't meet any of the above baseline characteristics received initial IFNα monotherapy.The remaining 48 patients treated with IFNα monotherapy for full treatment duration were considered as control.At week 24 of treatment,the treatment regimens were adjusted according to quantitative changes of HBV DNA,HBeAg and HBsAg:16 patients who achieved early response in group of initial IFNα and ADV combination therapy subsequently received IFNα monotherapy,the other patients in group of initial combination therapy together with patients who did not achieved early response in group of initial IFNα monotherapy subsequently received IFNα and ADV combination treatment.The HBV DNA levels,HBeAg and HBsAg titers were detected at the end of 48 weeks of treatment to determine the treatment duration.The treatment efficacy,safety,drug resistance and relapse rates were finally evaluated at week 72.All data were analyzed using chi square test.Results At week 24,the early response rate in group of initial combination therapy was 28.6%,and the HBV DNA negative rate and alanine aminotransferase(ALT)normalization rate were significantly higher than those in groups of initial IFNα monotherapy and control(53.6%vs 32.7%vs 27.1%and 62.5%vs 40.4%vs 37.5%,respectively,P<0.05);in addition,HBeAg loss rate was higher than control group(39.3%vs 18.8%,x2=7.48;P<0.05).At week 48,five of 16 patients who achieved early response developed HBeAg reversion and three cases accompanied with virological breakthrough in group of initial combination therapy after switching to IFNα monotherapy,while the rates of HBV DNA negative,HBeAg seroconversion and HBsAg clearance were 73.2%,41.1%and 12.5%,respectively.The HBV DNA negative rate,HBeAg seroconversion rate and HBsAg clearance rate in 96 patients Who had received different combination treatment regimens were 65.6%,33.3%and 8.3%,respectively.At week 72,the relapse rate in individualized treatment group was comparable to those in control group,while HBsAg clearance rate increased 2.7%in individualized treatment group.Conclusions IFNα and ADV combination treatment could improve early biochemical and virological responses.Individualized treatment strategy based on baseline characteristics and treatment responses may be helpful for optimizing antiviral treatment in CHB patients.