ABSTRACT
Background: There have been few reports on relationships between Shift Work (SW) and time to Noise-Induced Hearing Loss (NIHL). This research explores the relation between SW and time to NIHL among male workers. Methods: Between 1990 and 2015, this historical cohort study was conducted. Two different definitions events (Low Frequency Hearing (LFH) and High Frequency Hearing (HFH)) of NIHL An average pure-tone hearing threshold was thresholds at 1, 1.5 and 2 kHz for LFH(un-normal>20) and 4, 6 and 8 kHz for HFH (un-normal>20) for Air (AC) and Bone (BC) conduction, in both ears, respectively. In this study Kaplan-Meier and Multilevel Cox Model in addition R version 3.2.1 and MLWiN software used to analysis data. P-values less than 0.05 are considered to be statistically significant. Results: There were 6632 male workers in the research survey (mean age=35(±5)). Among these subjects, 2678 (40%),278 (4%) and 3676 (56%) were Day Workers (DW), Weekly Rotating Shift workers (WRS) and Routinely Rotating Shift workers (RRS), respectively. The result of this study showed more hazard risk of ear problem in LFH (Hazard=1.55 with 95% CI= (1.06-1.39)) and HFH (Hazard=1.08 with 95% CI= (1.04-1.13)) in RRS rather than day workers. In WRS group ear problem has been seen just in LFH (Hazard=1.55 with 95% CI= (1.2-2.0)). Conclusion: The findings of the 15-year historical cohort study generally support a relationship between SW and time to NIHL. Therefore, more actions in the field of noise control, greater use of safety devices as well as increased staff training on the use of safety devices recommended for shift worker.
ABSTRACT
AIM: Survey of the survival levels of gastric cancer and its effective causes. BACKGROUND: The survival of gastric cancer because of the advances in this type of cancer cures has been increased during the last decades. METHODS: 643 patients evolved by gastric cancer referred to Imam Khomeini hospital of Sari (2007- 2013) were studied. According to this method, the numbers of 74 patients were neglected because of defective data, and the number of 569 patients went under study. The level of survival was determined by use of Kaplan Meier, so to determine the causes affecting on the patients' survival, the univariate analysis of Log-rank test was used. RESULTS: Regarding the follow up of these patients during 2013 Nov-Dec the one, 2, 3, 4 and 5 years of survival of these patients were estimated equal to 0.77, 0.65, 0.52, 0.44, 0.27 percent and the survival median equal to 19 months, so survival means equal to 24.49 months. Based on the ranked logarithm test and FDR method some variables like stage (p<0.001) Radiotherapy (p<0.005) and undergo Surgery before Adjuvant chemotherapy (p<0.001) were determined as the effective factors on the survival probability. CONCLUSION: The life length of the patients under this article in comparison with developed countries is shallow that might be because of late reference or delayed diagnosis and the shortness of cure facilities. In this way, some materials like soon diagnosis and screen methods could be effective on the increase in patients' survival.
