ABSTRACT
Objective To investigate the correlation between incidence rate of tinnitus and noise exposure time,age,hearing condition in noise exposure workers.Methods A total of 1 985 noise exposure workers (age between 20～60 years old;working length between 1 ～30 years) in a large dockyard were randomly selected as the subject of this study with 1 831 male workers and 154 female workers in average 36.3±8.25 years old.The average noise exposure time was 9.1±6.50 years and pure tone threshold of final candidates in sound-proofed environment was evaluated (at 0.25～8 kHz).The subjects were divided into four groups according to the subjective tinnitus level:mild tinnitus,moderate tinnitus,severe tinnitus and no tinnitus to analysis the correlation among incidence rate of tinnitus and noise exposure time,age,hearing condition,etc.Results Among all 1 985 subjects enrolled the occurrence rate of tinnitus was 20.55％ (408/1 985),with 367 acquired mild tinnitus(89.95％),39 acquired moderate tinnitus (9.56％) and 2 for severe tinnitus (0.49％).Mild tinnitus and moderate tinnitus showed a multi-step raising according to noise exposure time.Mild tinnitus increased continually with age while moderate tinnitus showed an accumulation in age group over 55 years old.Female was less likely to be annoyed by tinnitus than male.Conclusion Tinnitus can be early warning of auditory damage by noise exposure;older male group with longer noise exposure time is more vulnerable to tinnitus.Tinnitus acquired in noise environment is more likely to be mild.
ABSTRACT
ObjectiveTo observe the effect ofZuogui Jiangtang Jieyu Formula on the expressions of glutamate, NR2A and NR2B in hippocampus of diabetic rats with depression;To explore the mechanism of protective effect. Methods Diabetes with depression rat models were established and then were randomly divided into the model group, positive medicine group, high-, medium- and low-doseZuogui Jiangtang Jieyu Formula groups. Normal rats acted as normal group, 16 rats per group. After 28 days of administration, Open-field test was used to detect the behavior of the rats;glutamate content of hippocampus was detected by ELISA;the expressions of NR2A and NR2B in rat hippocampus were detected by immunofluorescence.Results Compared with normal group, automatic activity times of rats in model group decreased significantly (P<0.01);both glutamate content (P<0.01) and expressions of NR2A, NR2B (P<0.01) increased significantly. Compared with the model group, automatic activity times of rats in positive medicine group and high-doseZuogui Jiangtang Jieyu Formula group significantly increased (P<0.01);glutamate content dropped (P<0.01);expressions of NR2A and NR2B decreased (P<0.05).ConclusionZuogui Jiangtang Jieyu Formula can improve depressive behavior of diabetic rats with depression, which may be related to the regulation of glutamate content and expressions of NR2A and NR2B in hippocampus.