ABSTRACT
OBJECTIVE@#To understand the usage of MP3 and effects on hearing of middle school students in Xi'an, and discuss controlling strategies.@*METHOD@#Stratified random cluster sampling method was used in the 1567 middle school students in Xi'an through questionnaire survey, ear examination and hearing examination, data were analysed by the SPSS13.0 statistical software.@*RESULT@#1) The rate of holding MP3 in the middle school students was 85.2%. Average daily use time was (1.41 +/- 1.11) h. 2) The noise group of pure tone hearing threshold was significantly higher compared with the control group (P<0.01), and increased the detection rate of hearing loss with the increasing use of MP3. 3) The detection rate of symptoms increased with the increasing use of MP3.@*CONCLUSION@#The usage of MP3 can harm hearing in middle school students, which can result in neurasthenic syndrome.
Subject(s)
Adolescent , Female , Humans , Male , Audiometry, Pure-Tone , Auditory Threshold , Data Collection , Hearing Loss , Hearing Tests , MP3-Player , Students , Surveys and QuestionnairesABSTRACT
OBJECTIVE@#To investigate the prevalence of vertigo and related risk factors in middle school students in the city of Xi'an.@*METHOD@#A cross-section study was used to investigate on vertigo among middle school students. Questionnaire ,ear examination and auditory tests were carried out by the staff who received special training. Multiple Logistic regression models were used to analyze the relative influential factors about vertigo.@*RESULT@#There were 1567 middle school students who underwent a complete investigation. The participants comprised 793 males (50.6%) and 774 females (49.4%). The overall prevalence of vertigo was 5.6%. No significant difference of the prevalence was found between males (4.7%) and females (6.5%) (P > 0.05). The use of MP3 or MP4, insomnia and history of middle ear infections or ototoxic drugs ingestion were the main risk factors for vertigo (odds ratio: 2.837, 5.582, 2.808 and 1.695, respectively).@*CONCLUSION@#Vertigo has an influence on the study and living of the students. More researches are urgently needed on prevention and treatment of vertigo.
Subject(s)
Adolescent , Child , Female , Humans , Male , Young Adult , China , Epidemiology , Logistic Models , Prevalence , Schools , Students , Vertigo , EpidemiologyABSTRACT
OBJECTIVE To establish the optimal animal model of tympanosclerosis.METHODS Staphylococcus were inoculated into the middle ear of guinea pigs,and the guinea pigs were sacrificed periodically.The changes of their middle ears were observed by light microscope,and the hearing threshold of the animals were measured.RESULTS All the inoculated ears showed different degree of mucosal adhesions after 7 days.The most common site of tympanosclerosis was hypotympanum,followed by the anterior epitympanum,the attic,the drum,the interossicular spaces,and the tubal orifice.CONCLUSION The pathological changes of the middle ear in guinea pigs with chronic otitis are similar to those of human being.It is a favorite animal model for researching on chronic otitis media with tympanosclerosis.