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1.
Background:Nursing work environment consists of a number of work-related psychosocial risk factors such as excessive workloads, lack of social support, emotional demands, job insecurity and confronting with challenging situations all of which may induce burnout. The aim of the current study was to investigate the relationship between work-related psychosocial factors and burnout among Iranian nurses.Methods:A cross-sectional study was carried out among 522 nurses. The data related to work-related psychosocial factors and burnout was gathered using Job Content Questionnaire (JCQ) and Maslach Burnout Inventory (MBI), respectively. Pearson’s correlation coefficients were used to examine the relationship between work-related psychosocial factors and burnout.Results:Mean scores of the dimensions of burnout for emotional exhaustion, depersonalization, and reduced personal accomplishment were 13.6 (SD=8.6), 18.42 (SD=7.1), and 28.45 (SD= 9.15), respectively. Psychological and physical job demands were positively correlated with different dimensions of burnout while social support and job control showed negative correlation with them.Conclusion:Appropriate interventions on reducing job demands both psychologically and physically and increasing social support and job control are suggested in prevention of burnout among the studied nurses.Key words: Burnout, psychosocial factors, nurses, job demands, job control, social support  相似文献   
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Background:Modern technology has reduced physical workload and imposed high mental workload on the control room operators in industrial settings. The present study was conducted among control room operators to assess their mental workload, investigate their workability, examine the relationship between mental workload and workability, and determine the factors associated with workability.Methods:This cross-sectional study was carried out among 213 control room operators in six Iranian process industries. Task Load Index (NASA-TLX) was used to assess the mental workload, and Work Ability Index (WAI) was used to determine workability. The relationships between demographic characteristics and dimensions of mental workload and workability were examined by univariate tests. Logistic regression analysis was also used to determine the factors associated with the operators’ workability.Results:The results showed a high mental workload in the study population (82.38±8.8). Yet, the operators showed a good and excellent level of workability (56.4%). Pearson’s correlation coefficient revealed a significant inverse linear relationship between the mean score of mental workload and workability (r=-0.581). Besides, regression modeling demonstrated that mental demand (OR=0.90), temporal demand (OR=0.90), effort (OR=0.91), frustration (OR=0.92), from NASA-TLX subscales were significantly associated with workability. Moreover, mental and temporal demands were important factors associated with reduced workability.Conclusion:Monitoring tasks imposes high mental workload on the control room operators, which may result in adverse effects on their workability as well as on the safety of the system.Key words: Mental workload, NASA-TLX, work ability, control room  相似文献   
3.
Observational studies have reported controversial evidence of the association between dietary fat intake and ovarian cancer. This dose–response meta-analysis aimed to clarify quantitatively the association between dietary fat intake and ovarian cancer. The linear and non-linear relationships between fat intake and risk of ovarian cancer were investigated. Heterogeneity, sensitivity analysis, and publication bias were also assessed. Overall, 21 studies involved approximately 900,000 subjects were included. A significant nonlinear association was found between total fat intake with the risk of ovarian cancer, with a relatively steep slope at total fat intake higher than 30?g/day (p non-linearity <.01). Moreover, the risk of ovarian cancer was increased in non-linear form for both saturated and monounsaturated fat from 25?g/day (p non-linearity <.05). According to the findings from the linear meta-analysis, we observed a 2, 2, 1, and 1% greater risk of ovarian cancer per 10, 0.5, 2.5?g/day and 50?mg/day increase in total, trans and monounsaturated fat intake as well as cholesterol, respectively. However, this association for monounsaturated fat was marginally significant (p=.052). The findings of this meta-analysis suggest that dietary total, trans, saturated and partially monounsaturated fat as well as cholesterol intake are positively associated with increased risk of ovarian cancer.  相似文献   
4.
Aim: To examine the efficacy of cognitive rehabilitation treatment (CRT) for people with opioid use disorder who were recruited into a methadone maintenance treatment (MMT) programme.

Method: 120 male subjects were randomly assigned to (1) MMT plus CRT in two months or (2) MMT plus a control intervention. Subjects were assessed at the beginning, mid-point and post-intervention as well as at 1-, 3- and 6-month follow-up time points.

Results: Analysis with repeated measure ANOVA showed that the CRT group performed significantly better in tests of learning, switching, processing speed, working memory and memory span. Moreover, the CRT group had significantly lower opiate use over the control group during 3-months follow-up. Analysis including only those with a history of methamphetamine use showed that the CRT group had significantly lower amphetamine use. No group differences were observed for treatment retention.

Conclusions: Our findings provide evidence that adding CRT as an adjunct intervention to MMT can improve cognitive performance as well as abstinence from both opiates and stimulants.  相似文献   

5.
Purpose: To compare the subclinical inflammatory response (as measured by anterior chamber flare) induced after standard (3 mW/cm2, 30 min) and accelerated (18 mW/cm2, 5 min) corneal cross-linking (CXL).

Methods: In this comparative, non-randomized study, patients with progressive keratoconus who underwent standard or accelerated CXL were studied. Laser flare photometery (FM-600; Kowa, Tokyo, Japan) was used to measure anterior chamber flare preoperatively and at 1 week, 1 month, 3 months, and 6 months after the procedure.

Results: Sixty eyes of 60 patients were studied; 30 eyes in each group. Mean baseline flare values were 4.15 ± 1.19 and 4.57 ± 2.17 ph/ms in standard and accelerated groups, respectively (p = 0.228).and after surgery increased in all follow-up measurements in the both groups similarly (P > 0.05).

Conclusion: Both standard and accelerated CXL results in induction of a subclinical inflammatory response that persists up to 6 month. The response was similar between the two groups.  相似文献   

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The associations of OPRM1 gene variants with opioid dependence have been demonstrated. This study investigated the association of rs495491, rs1799971 (A118G), rs589046, and rs10457090 variants of OPRM1 gene with opium dependence and their haplotypes among addicted individuals undergoing methadone treatment. Moreover, we investigated whether any of these variants were associated with libido dysfunction or insomnia among addicted people. A total of 404 individuals were genotyped by amplification refractory mutation system (ARMS) PCR. In silico studies were designed through homology modeling of A118G structures (N40 and D40) and docked with 41 FDA-approved drugs of OPRM1 protein by SWISS-MODEL, COACH, MolProbity, ProSA, Errat, Glide XP, and Autodock 4. Results revealed that rs495491, A118G, rs589046, and rs10457090 were significantly associated with opium dependence under recessive (P = 6.66E-10), dominant (P = 0.017), co-dominant (P = 0.001), and recessive (P = 9.28E-6) models of inheritance, respectively. Further analyses indicated three significant haplotypes including A-A-A-C (P-permutation < 1E-9), G-G-A-C (P-permutation = 0.04), and G-A-G-C (P-permutation = 8.69E-4). Genotype-phenotype associations of OPRM1 variants with insomnia and libido dysfunction showed no significant association. Docking showed the higher binding affinity of N40 rather than D40 model; however, methadone and morphine were bonded with D40 structure more powerful. Consequently, rs495491, A118G, rs589046, and rs10457090 were associated with opioid dependence among Iranians; also, A118G might be the most remarkable marker of OPRM1 owing to its vital structural roles.  相似文献   
10.
Journal of Molecular Neuroscience - Alzheimer's disease is associated with biochemical and histopathological changes characterized by molecular abnormalities. Due to the lack of effective...  相似文献   
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