Objective Exploration of best effect on washing medical instrument between automatic cleaning sterilizer and ultrasonic cleaners.Methods Suppose washing method A and method B.A:directly put medical instrument into automatic cleaning sterilizer,wash,sterilize and dry it step by step.B:place medical instrument into ultrasonic cleaners,wash with ultra sonic,shower with cool water,sterilize and dry with hot water.Results By comparison,after washing method A,there remains 0.33‰ residue on the medical instrument while after B there are 0.03‰ remains.It has an evident difference between result of the two methods(?~2=46.546,P=0.000).Especially on the cleaning result of saw-shaped medical instrument:A method has 0.52‰ residue while method B is 0.04‰,which is of great significance.But there exists no significant difference of washing result on non saw-shaped instrument(?~2=2.667,P=0.102).Conclusion Ultrasonic cleaners can reach the optimum washing effect on saw-shaped medical instrument,with a great decline on residue after cleaning.And automatic cleaning sterilizer can wash large quantity of non saw-shaped,saving labor and enhancing efficiency by automation cleaning process.Therefore,adpoting different equipment to wash different instrument can efficiently improve cleaning effect and ensure safe and qualified stelization.

Objective To confirm the performance of rate method for detecting ALT in blood donors to verify that it meets the requirements of ISO15189 .Methods according to the requirements of CNSA‐CL02 :2012 the Medical Laboratory Quality and Abili‐ty Recognized Standards and the Blood Station Technical Operation Regulations(edition 2012) ,the precision ,accuracy ,sensitivity , reportable range ,biology reference interval and measurement uncertainty of the detection system were verified .Results The intra‐batch imprecision for the ALT quality control serum and 2 concentrations of blood donor sample detected for 20 times and 20 d was<5 .0% and the inter‐batch imprecision was <6 .7% ;the correct estimates passed the external quality assessment results of the original Ministry of Public Health in 2014 and calibration results analysis .The relative bias was less than 1/2 of CLIA′88 permissi‐ble error;the regression equation of reportable range obtained by the linear regression was Y =0 .995 1X -5 .618 4 ,r=0 .999 7 (R2 =0 .999 4) ,the results within the detection range were correct ;the biological reference interval was 0 .0 -32 .7 U/L and the measurement uncertainty was (74 .90 ± 3 .32)U/L .Conclusion The performance indexes of ALT detection method conform to the expected requirements of ISO15189 .This method can be used as a blood screening test method in laboratory .