In order to establish a method for the detection of serum antibodies to donkey-derived e-quine coronavirus(ECoV),recombinant ECoV N protein was expressed in E.coli system,purified by nickel column affinity chromatography and identified by Western blot.After optimizing the re-action conditions,the indirect ELISA(iELISA)detection method was established using the puri-fied recombinant protein as coating antigen and used to detect 143 clinical serum samples.The re-sults showed that the recombinant N protein,which has good reaction activity with serum antibod-y,was successfully expressed.The optimum conditions of the established iELISA method were as follows:the amount of antigen coated was 0.2 μg/well and overnight at 4 ℃,10％skimmed milk powder solution was sealed at 37℃ for 1.5 h,the dilution concentration of serum was 1∶200,and the enzyme-labeled secondary antibody diluted at 1∶10 000.The sensitivity test results showed that the positive serum could be diluted to 1∶6 400.The specificity test results showed that all an-tibodies to several donkey pathogens were negative.The repetitive test results showed that the in-tra-and inter-batch coefficients of variation were 2.90％-6.12％and 2.29％-7.88％respectively.The positive rate of clinical donkey serum was 57.3％.The iELISA established in this study pro-vides a technical support for epidemiological investigation and antibody surveillance.

In order to establish a method for the detection of serum antibodies to donkey-derived e-quine coronavirus(ECoV),recombinant ECoV N protein was expressed in E.coli system,purified by nickel column affinity chromatography and identified by Western blot.After optimizing the re-action conditions,the indirect ELISA(iELISA)detection method was established using the puri-fied recombinant protein as coating antigen and used to detect 143 clinical serum samples.The re-sults showed that the recombinant N protein,which has good reaction activity with serum antibod-y,was successfully expressed.The optimum conditions of the established iELISA method were as follows:the amount of antigen coated was 0.2 μg/well and overnight at 4 ℃,10％skimmed milk powder solution was sealed at 37℃ for 1.5 h,the dilution concentration of serum was 1∶200,and the enzyme-labeled secondary antibody diluted at 1∶10 000.The sensitivity test results showed that the positive serum could be diluted to 1∶6 400.The specificity test results showed that all an-tibodies to several donkey pathogens were negative.The repetitive test results showed that the in-tra-and inter-batch coefficients of variation were 2.90％-6.12％and 2.29％-7.88％respectively.The positive rate of clinical donkey serum was 57.3％.The iELISA established in this study pro-vides a technical support for epidemiological investigation and antibody surveillance.

Objective To improve the efficiency of blood collection in hemodialysis patients by inventing and applying new blood collection needles.Methods One hundred and eighty cases of hemodialysis patients were randomly divided into control group 1(CG1),control group 2(CG2),experimental group(EG). Comparison of the three groups in time of blood collection,the number of operation that had the risk of acupuncture injury and the number of the blood samples that had been contaminated. Results There were statistically significant difference (P<0.05)in three groups.The number of times of blood collection in the number of operations that had the risk of acupuncture injury,and the number of the blood sample that had been contaminated. CG1 had the longest blood collection time(12.55 min),EG had the shortest blood collection time(5.09 min);the risk of acupuncture injury was the highest in CG2 and the lowest in the EG.The number of contamination of blood samples and the amount of inaccurate sample in CG1 were the highest,and the lowest in the EG. Conclusions The working efficiency of transfer type anti-acupuncture needle(TTAN)during blood sample collection in hemodialysis patients is signifi-cantly better than that of traditional blood collection method,and it is helpful to reduce the risk of acupuncture injury and the risk of contamination in blood samples,which is worthy of promotion.