Objective: In order to observe the kinds and intensity of the working noise of Yansan Petrochemical Co. and the effects caused by the working noise on the workers＇ vestibular and auditory function. Method :The intensity and frequency of the working noise were recorded by exactolnoisemeter in the workshop. One hundred and seventeen workers were tested in routine pure-tone tested method. The SPVN and ABR were tested within fifty-one workers of all. Result:The working noise of Yansan Petrochemical Co. belongs to the broad band and steady noise. The intensity of the working noise were during 85.7～104.0 dB (A) and the main frequency were during 1～8 kHz. About 59 percent workers who exposed to the working noise had hearing loss. The most hearing-loss were in the high frequency. The hearing-loss of speech frequency were slight. Workers who have more six years standing have obviously increased hearing-loss than the workers who have less five years standing. There were significant differences the ABR thresholds and wave-interval between the tested and controlled groups. The SPVN and CP were abnormal in more than 17.4 percent workers with hearing loss. Conclusion: The working noise of Yansan Petrochemical Co. belongs to the broad band and steady noise. Working noise can lead to workers＇ hearing loss of certain degrees who exposed in the noise for a long time. Obvious correlation was not defined between the hearing-loss and the abnormal vestibular response group.

Background: Disruption of tight junctions between intestinal epithelial cells followed by loss of barrier function is crucial for the pathogenesis and progression of a variety of gastrointestinal disorders.Aims: To investigate the protective effect of ulinastatin on hydrogen peroxide (H2O2)-induced intestinal epithelial barrier disruption.Methods: Model of intestinal epithelial monolayer barrier was established with Caco-2 cells in vitro,and then divided into four groups: blank control group (without any intervention),H2O2 group (500 μmol/L H2O2),low-dose (500 U/mL) and high-dose (3 000 U/mL) ulinastatin groups (ulinastatin + H2O2).Level of malondialdehyde (MDA) and activity of superoxide dismutase (SOD) were detected;transepithelial electrical resistance (TEER) and flux of sodium fluorescein were measured to assess the barrier function;expression and localization of two tight junction proteins,ZO-1 and occludin were evaluated by Western blotting and immunofluorescence;ultrastructure of tight junctions was observed by transmission electron microscopy (TEM).Results: Compared with the blank control group,treatment of Caco-2 cell monolayers with H2O2 resulted in increase in level of MDA,flux of sodium fluorescein and decrease in activity of SOD,TEER and expressions of ZO-1 and occludin (P all ＜0.05).TEM and immunofluorescence showed that the brusher border of Caco-2 cells in H2O2 group was destroyed,the cell-cell junction was vague and the localization of ZO-1 and occludin was discontinuous and the fluorescence intensity was extremely low.While in ulinastatin groups,especially the high-dose group,all the indices above-mentioned were significantly improved (P all ＜0.05).Conclusions: Ulinastatin protects intestinal epithelial monolayer barrier against H2O2-induced disruption at least partially by its antioxidant activity and modulating expression and localization of tight junction proteins.