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This study aimed to assess the relationship between shift working and occupational exposure to noise with blood pressure (BP). The study was carried out in a rubber manufacturing company in 2010. Demographic, medical and occupational information for carrying out the study were collected through direct interview. All 331 under study workers were divided into four groups according to work shift and noise exposure severity, from non-noise exposed day time workers (Group 1) to noise exposed shift workers (Group 4). Finally, systolic and diastolic blood pressure levels were compared among these four groups. The results of this study showed that there was a significant difference between average systolic and diastolic BP and hypertension (HTN) frequency in the four groups (p<0.05). The highest rate of HTN and mean systolic and diastolic BP were observed among shift workers who were exposed to noise higher than permissible limit (Group 4). Also the results of logistic regression analysis showed that there was a significant relationship between simultaneous exposures to noise more than the permitted limit and shift work with HTN (p<0.05). The results of our study showed that shift working and simultaneous exposure to noise have an additive effect on occurrence of HTN. It is recommended that during periodic physical examinations of noise exposed shift workers, assessment of the cardiovascular system and BP should be done as well as the auditory system. 相似文献
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Cortical Bone Augmentation Versus Nerve Lateralization for Treatment of Atrophic Posterior Mandible: A Retrospective Study and Review of Literature 下载免费PDF全文
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Prognostic significance of recurrent chromosomal aberrations detected by comparative genomic hybridization in sporadic colorectal cancer 总被引:6,自引:0,他引:6
De Angelis PM Stokke T Beigi M Mjåland O Clausen OP 《International journal of colorectal disease》2001,16(1):38-45
Colorectal carcinomas are characterized by frequent recurrent gains and losses of chromosomal material, especially gains of chromosome arms 20q and 13q, and losses of chromosome arms 18q and 4q. These may be important in the development and progression of colorectal carcinomas. Chromosomal aberrations detected by comparative genomic hybridization in 67 sporadic colorectal carcinomas were examined for their possible associations with patient survival. Dukes' stage, tumor DNA ploidy status, and TP53 genotype/phenotype were also examined for the same. Patients with losses of chromosomal arms 1p, 4q, 8p, 14q, or 18q or gain of chromosomal arm 20q had significantly shorter survival times than those without these aberrations (univariate relative risk 3.45, 2.71, 3.32, 3.26, 3.32, 3.91, respectively), as did patients with more than six chromosomal aberrations per tumor than those with fewer than six aberrations (univariate relative risk 3.26, P = 0.013). DNA aneuploidy and Dukes' stage C + D resulted in poor patient survival (univariate relative risk 3.58, 3.39, respectively). Dukes' stage C + D, 1p loss and 8p loss emerged as the only independent prognostic parameters (relative risk 3.22, 2.53, 2.45, respectively) when entered into multivariate survival analysis together with other significant parameters from univariate survival analysis. Loss of chromosome arm 1p, 4q, 8p, 14q, or 18q or gain of chromosome arm 20q thus results in shortened survival times in colorectal cancer patients. 1p loss and 8p loss were shown to be independent predictors of poor prognosis. 相似文献
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ObjectivePersonal identification is an essential issue when mutilated and amputated limbs or parts of the body are found in mass disasters. Estimation of the stature from the size of different parts of the body is one of the most important items in personal identification. The aim of this study was to estimate the stature from upper limb anthropometry.Materials and methodsHeight, left upper limb, left arm, left forearm, length and breadth of the left hand, and length of the left second to fifth fingers were measured on 100 right-handed Iranian medical students aged between 21 and 26 years from February to may 2010.ResultsAfter analyzing the datas, it was shown that there is a meaningful relation between the stature and upper limb dimensions (p < 0.05), [correlation coefficients ranged from 0.310 to 0.696 in males and 0.299 to 0.735 in females].ConclusionThe regression formula derived in this study can be used for forensic pathologists and Anthropologists. 相似文献
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This paper examines the electrochemical and microstructural features of SrCo0.8Fe0.1Ga0.1O3−δ (SCFG) with a fibrous structure infiltrated by an SDC electrolyte for use as a cathode in solid oxide fuel cells (SOFCs). An electrospinning process is used to produce SCFG fibers. In a symmetrical cell, Sm0.2Ce0.8O1.9 (SDC) nanoparticles are infiltrated into the porous fibrous SCFG cathode layer after it was applied to the SDC dense electrolyte. Electrochemical impedance spectroscopy (EIS) analysis reveals that the polarization resistance of the SCFG cathode with fiber morphology is significantly lower than that of the same combination with powder morphology. In addition, it is shown that infiltration of SDC oxygen ion conductor nanoparticles enhanced electrochemical performance. The lowest value of polarization resistance, 0.03 Ω cm2 at 800 °C, is attained by the SCFG with a fibrous structure containing 14 wt% SDC nanoparticles. 相似文献
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Esfahani ST Hamidian MR Madani A Ataei N Mohseni P Roudbari M Haddadi M 《Pediatric nephrology (Berlin, Germany)》2006,21(8):1153-1156
We evaluated changes in serum zinc (Zn) and copper (Cu) levels in two groups of children with chronic renal failure (CRF) – children with CRF who were on regular hemodialysis (Group 1, n=40) and children with CRF who were on conservative management (Group 2, n=31) – and in one group of healthy children (Group 3, n=30). All of the participants in the study were between 5–18 years old, and the composition of the three groups was almost identical with respect to age and sex. The length of time the children in Group 1 had been on hemodialysis varied between 3 and 52 months (mean: 20.97±14.8 months). To evaluate the impact of the duration of dialysis on serum levels of Zn, we further sub-divided Group 1 patients into two subgroups: Subgroup A patients (n=20) had been on hemodialysis therapy for less than 18 months (mean: 8.85±4.83 months); Subgroup B patients (n=20) had been on hemodialysis therapy for longer than 18 months (mean: 33.1±10.86 months). The PIXE (proton-induced X-ray emission) was used for measuring the trace elements. Results: The mean serum level of Zn was lower in the Group 1 (hemodialysis group) children than in the children of Group 2 (on conservative management) and group 3 (healthy children) (p<0.001), but the difference was not significant between Groups 2 and 3. No significant differences in serum levels of Cu were found among the three groups. The serum level of Zn was lower in Subgroup B than in Subgroup A (p<0.001). The correlation test showed that there was an inverse linear relation between the length of time the child was on the hemodialysis regimen and serum Zn levels. Conclusion: Chronic hemodialysis may lead to abnormalities in the serum levels of some trace elements in children with CRF that increase in severity with increasing duration of hemodialysis. Deficiencies of these trace elements – zinc in particular – may contribute to various conditions and symptoms in children undergoing chronic hemodialysis. 相似文献
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