Objective To explore the relationship between HBV-DNA load and the offspring vertical transmission of HBV.Methods 138 families who had taken the examination between August 2009 and November 2011 but the HBsAg of the housewife was negative,were chosen as research objects.Blood from the couples and sperms from the husbands during pregnancy were followed and collected for detection on related indicators.Cord blood was sampled after delivery for HBVM and HBV-DNA quantification.Those with HBV-DNA load ≥5 × 102 copies/ml were chosen as cases while those ＜5 × 102 copies/ml were formed as controls,respectively.Results 1) The positive rates of HBV-DNA was 34.8％ (48/138) in the neonatal cord blood while the positive rates of cord blood HBsAg and HBeAg were 28.3％ (39/138) and 15.2％ (21/138) respectively.2) The positive rate of semen HBV-DNA was 21.0％ (29/138) while the positive rates of paternal serum HBV-DNA and HBeAg were 76.8％ (106/138)and 42.8％ (59/138).3)Among the positive ones on paternal serum HBV-DNA,paternal serum HBeAg,semen HBV-DNA,items as measures taken for HBV vertical transmission and prevention on the fathers and the first class family histories on HBV appeared to be the risk factors for HBV paternal transmission (P＜0.05).4)Data from Multivariate analysis showed that positivities on patemal serum HBV-DNA,paternal serum HBeAg and semen HBV-DNA were risk factors for HBV paternal transmission (OR=5.7,95％CI:1.1-29.1 ; OR=4.2,95％CI:1.7-10.0; OR=6.7,95％ CI:2.4-18.9).5)Dose-response relationships were seen between levels of paternal serum HBV-DNA load and cord blood HBV-DNA load,between levels of paternal serum HBV-DNA load and semen HBV-DNA load,between levels of semen HBV-DNA load and cord blood HBV-DNA load.6)Results from the analysis on ROC curve showed that paternal serum HBV-DNA load level (105 copies/ml) and semen HBV-DNA load level (103 copies/ml)were better demarcation points to forecast the occurrence of paternal transmission of HBV,because of the better sensitivity and specificity they had.Conclusion Items as positives on paternal serum HBV-DNA,paternal serum HBeAg and semen HBV-DNA were risk factors for HBV paternal transmission.When paternal serum HBV-DNA load ＞ 105 copies/ml and semen HBV-DNA load ＞ 103 copies/ml appeared,the positive rate of HBV paternal transmission would increase.

Objective To compare the morphology differences in small shadows of occupational pneumoconiosis (hereinafter referred to as "pneumoconiosis") between computed tomography (CT) and digital radiography (DR) imaging. Methods A total of 1 010 pneumoconiosis patients were selected as the research subjects using a judgment sampling method. Chest DR imaging and CT imaging were performed on patients, and the differences in small shadow morphology between the two images were compared. Results In both DR and CT images of patients, circular small shadows identified as p, q, and r shapes accounted for 76.2%, 11.5%, and 1.3%, respectively, while irregular small shadows were identified in 1.8% of cases. There was medium high consistency between DR and CT in detecting these four types of small shadow morphology (Kappa=0.72, P<0.01). The detection rate of irregular small shadows (including interlobular septal thickening, ground-glass opacity, and/or centrilobular emphysema) by CT images was 54.0% (545/1 010), with 88.6% (483/545) of these cases also showing small circular shadows. Irregular small shadows in CT images were mostly identified as p small circular shadows in DR images, accounting for 88.8% (484/545). The results of DR and CT images for p/p, p/q, q/p, q/q, q/r, r/q and r/r in small circular shadows showed medium high consistency (Kappa =0.52, P<0.01). Conclusion The results of CT and DR imaging for pneumoconiosis with small shadow were of medium high consistency, with CT demonstrating advantages in detecting irregular small shadow morphology of pneumoconiosis. CT images can be used to describe the shape of circular small shadow as DR images, and irregular small shadow can be described as interlobular septal thickening, ground-glass opacity, and/or centrilobular emphysema.