title: [Study of protective effects on noise-induced hearing impairment by D-methionine tablets pre-loading].
abstract: OBJECTIVE
  To evaluate the protective effects of oral administration of D-methionine tablets on noise-induced hearing impairment.
  
  
  METHODS
  Two hundred and three volunteers were recruited and randomly divided into two groups: experimental group (n= 113) and control group (n=90). The subjects received oral administration of D-methionine tablets in the experimental group and placebo in the control group before noise exposure. Routine audiometric evaluation and ABR testing were performed and recorded before and after noise exposure. The statistical analysis was carried out with SPSS 11.0.
  
  
  RESULTS
  There were no differences in auditory threshold and I-V interpeak latency pre-noise exposure (P>0.05), however, there were statistically significant differences between two groups 1 d, 7 d after noise exposure (P<0.01 and P<0.05). In-respective-group, there were statistically significant differences between before and 1 d after noise exposure (P<0.05 and P<0.01), however, no difference was noted between before and 7 d after noise exposure in the experimental group (P>0.05).
  
  
  CONCLUSIONS
  The protective effects of D-methionine tablets were prominent on the noise-induced hearing impairment. Further studies regarding the optimal time of D-methionine administration will be recommended in the future.
authors.forename: Zhenmin
authors.initials: Z
authors.lastname: Ge
authors.forename: Shu
authors.initials: S
authors.lastname: Ma
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Jia
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Song
mesh_terms: D000284:Administration, Oral; D000328:Adult; D006317:Hearing Loss, Noise-Induced / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008715:Methionine / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D008715:Methionine