Objective To study the performance verification of lactate dehydrogenase(LDH) in the Johnson Vitros 5 .1 FS bio‐chemical analyzer .Methods According to CLSI instrumentation evaluation standard and referring to the validation scheme provided by the Johnson company ,the precision ,accuracy ,linear range of LDH ,maximum dilution degree ,biological reference range were verified .Results The LDH intra‐batch and inter‐batch precision experiments were≤3 .30% ;the accuracy experiment≤4 .00% ;the determination coefficient of the linear experiment was 0 .997 2 ;the LDH maximum dilution degree was 8 times with saline solution dilution;the biological reference range experiment verified that the reference range 313-618 U/L provided by the VITROS Meth‐odology Manual could be quote .Conclusion The performance verification of LDH detected by the Johnson Vitros 5 .1 FS biochemi‐cal analyzer basically conforms to the requirements of the quality objectives and manufacturer′s instructions ,and meets the needs of clinical test .

A plasmids of continuous expressing shRNAs targeting the NDV NA-1 Phosphoprotein (P) gene was designed.Virus titration,Real Time RT-PCR,CPE indicated that P-specific siRNA could inhibit virus replication at 36 h post-virus infection.In future studies,a combination of siRNAs targeting the NP and L gene may be used as a tool to study NDV replication and antiviral therapy.

Objective:Patients are breathing freely during adjuvant proton pencil beam radiotherapy after breast conserving surgery. Fluctuation of the thorax may affect the position of the end of the proton beam flow, which needs to be precisely evaluated on a millimeter scale.Methods:For 20 patients with breast cancer treated with proton radiotherapy after breast conserving surgery, PET-CT scan was performed approximately 10 min after the end of proton radiotherapy. The images of PET-CT were processed for ROI determination and sampling line (profile) extraction on a Raystation RV workstation to calculate the actual difference between the predicted and real radioactivity from the same spatial location as obtained by PET acquisition R50. Then, the differences in the spatial location between the actual process of proton irradiation and the planned process were obtained. Depth difference values for each pair of sampling lines were presented. Results:For 20 patients with breast cancer with a median follow-up of 22 months (range 12 - 46 months), all patients survived at the last follow-up, and no radiation pneumonitis was observed during the follow-up period. Among the verification results of 21 cases, the depth difference of evenly distributed was (-0.75±1.89) mm in the primary field and (-0.82±2.06) mm in the secondary field; The depth difference of sequential treatment was (1.81±1.87) mm in the primary field and (1.32±1.74) mm in the secondary field; The depth difference of synchronous addition in the primary field was (-1.47±1.44) mm, and the depth difference in the secondary field was (-1.48±2.11) mm.Conclusion:The results of off-line PET-CT in vivo biological verification show that the accuracy of the dose boundary cut-off was within 3 mm in breast cancer patients, which meets the clinical and physician requirement for the precision in breast cancer treatment.

ObjectiveTo investigate the efficacy and safety of N-acetylcysteine （NAC） in the treatment of severe alcoholic hepatitis （SAH）， and to provide a basis for clinical medication for SAH. MethodsA prospective randomized controlled trial was conducted among 172 SAH patients with a Maddrey discriminant function score of >32 points who were recruited by The Fifth Medical Center of Chinese PLA General Hospital from June 2015 to June 2018， and these patients were divided into NAC group with 84 patients and control group with 86 patients. NAC （8 g/day， 28 days） was assessed in terms of its safety in SAH patients， its impact on 28-day biochemical parameters， and its role in improving 28- and 180-day survival rates. A further analysis was performed to investigate the effect of NAC on the 28- and 180-day survival rates of SAH patients with acute-on-chronic liver failure （ACLF-SAH patients） and those without acute-on-chronic liver failure （non-ACLF-SAH patients）. The independent-samples t test was used for comparison of normally distributed continuous data between two groups， and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups. The Kaplan-Meier method was used to plot survival curves， and the Log-rank test was used for comparison of survival curves. Univariate and multivariate Cox proportional-hazards regression model analyses were used to investigate independent influencing factors. ResultsNo serious adverse events were observed during NAC treatment， suggesting that NAC had a good safety profile. Compared with the control group， NAC did not significantly improve the 28-day biochemical parameters （all P>0.05） and survival rate of SAH patients （P=0.081）， but it could improve the 180-day survival rate of SAH patients （67.4% vs 81.0%， χ²=4.280， P=0.039）. NAC did not improve the 28- and 180-day survival rates of ACLF-SAH patients （both P>0.05）； NAC did not improve the 28-day survival rate of non-ACLF-SAH patients （P>0.05）， but it could improve the 180-day survival rate of these patients （68.4% vs 88.9%， χ²=4.883， P=0.027）. The multivariate Cox regression survival analysis showed that NAC treatment （hazard ratio ［HR］=2.530， 95% confidence interval ［CI］： 1.334‍ ‍— 4.796， P=0.004，）， Maddrey discriminant function score （HR=3.852， 95%CI： 2.032 — 7.304， P<0.001）， and serum sodium level （HR=1.948， 95%CI： 1.079‍ ‍—‍ ‍3.517， P=0.027） were independent influencing factors for 180-day survival rate in SAH patients. ConclusionNAC has a good safety profile in the treatment of SAH and can improve the 180-day survival rate of SAH patients， and in particular， non-ACLF-SAH patients can benefit from NAC treatment in terms of middle- and long-term survival rates.