Objective To investigate the correlation between the positive rate of PCR-reverse dot blot genotyping test and the loads of the viral nucleic acid. Methods The fluorescent PCR assay was used to detect the high-risk HPV(HR-HPV)DNA loads in the cervical mucus samples from 1162 female pa-tients. Patients with positive HR-HPV DNA were further analyzed by PCR-reverse dot blot hybridization as-say for HPV genotyping. Results The overall positive rate of genotyping test was 68. 8% . The positive rate of genotyping test had a significant positive correlation with the Log Koc of HR-HPV DNA loads(r=0. 944, P﹤0. 01). The quadratic curve fitting formula was Y= -1. 806+0. 558X-0. 031X2(Y for genotyping positive rate,X for Log Koc of HR-HPV DNA loads). There were significant differences with the positive rate of gen-otyping test among patients with different viral loads(P﹤0. 01). When HR-HPV DNA loads were 104-105 copies/ ml,105-106 copies/ ml,106-107 copies/ ml and more than 107 copies/ ml,the positive rate of HPV genotyping test were 27. 8% ,48. 5% ,74. 0% ,97. 5% and 33. 3% ,51. 5% ,78. 0% ,97. 5% respective-ly by using different genotyping detection reagents. Conclusion The positive rate of PCR-reverse dot blot genotyping test was correlated with the loads of HPV nucleic acid.

Objective To select and evaluate the diluents for quantitative detection of HBV DNA of high loads sample,hope to find the most applicable diluents which could be used in clinical test.Methods The standard substance(2.00 × 109IU/ml)was 10 and 100 times diluted by different diluents,compare the result of test,and the bias was analysis taking negative quality control as standard diluents,negative serum,physiological saline,and distilled water as candidate diluents.Results When 10 times diluted,there was no statistically difference between the standard diluents and distilled water as diluents(t =2.04,P ＞ 0.05),the bias were less than the TEa regulated by professional standard.When used negative serum and physiological saline as diluents,the results were higher than that of standard diluents (P ＜ 0.05),and the ratio of the bias higher than the TEa was 16.67％ and 20.00％.When 100 times diluted,the results of candidate diluents were higher than that of standard diluents.In this time,the result of distilled water diluted detection presented a good linear relationship with the result of standard diluted detection,the formula was Y =0.963X + 0.267 (Y =result of standard diluted detection,X =result of distilled water diluted detection).All the bias were less than the TEa,the sequence of bias sort by ascending counts were negative quality control,distilled water,physiological saline and negative serum.Conclusions The most applicable diluents were negative quality control and distilled water with 10 times dilution.When 100 times diluted was used,the most applicable diluents was negative quality control,then was distilled water,physiological saline and negative serum.If using the distilled water to dilute,we could corrected the result by the formula Y =0.963X + 0.267 to ensure the result to be more exactly.