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Purpose: The aim of this study is to compare the effect of smoking in corneal endothelial cell number and morphology by specular microscopy on a non-smoker population.

Methods: Our cross-sectional study was performed on 150 participants from a non-smoker population. Non-contact specular microscopy (Tomey Corporation Inc., Nagoya, Japan) was performed in the center of the cornea of all subjects. The cell density (CD), average cell size (AVG), percent of hexagonality (HEX%) and central corneal thickness (CCT) were calculated and compared in both groups.

Results: Totally, 76 eyes of 76 smokers and 74 eyes of 74 non-smokers were enrolled in the study from 2015 to 2016. The mean age of smokers and non-smokers were 48.61?±?17.04 and 46.39?±?13.02, respectively. The mean number of pack/year among the smokers was 17.36?±?14.68. Also, the mean values of AVG and CD were significantly different for these two groups (p?=?0.011 and p?=?0.039, respectively). Other corneal endothelial variables did not show a significant difference between smokers and non-smokers (p?>?0.05). However, smokers with severe nicotine dependency had significantly greater AVG and lower CD in comparison with the non-smokers (p?=?0.004 and p?=?0.013, respectively).

Conclusion: Our study showed that smoking can cause significant changes in some of the corneal endothelial variables, but not all of them.  相似文献   
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This study aimed to investigate the electro-degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solution using two and three-dimensional electrode (2D and 3D) reactors with graphite(G)/β-PbO2 anode. To increase the degradation efficiency, affecting parameters on the electro-degradation process were investigated and optimized by adopting the Taguchi design of experiments approach. The structure, morphology and electrochemical properties of the electrodes were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), linear sweep voltammetry and cyclic voltammograms. The controllable factors, i.e., electrolysis time, 2,4-D initial concentration, solution pH and current density (j) were optimized. Under optimum conditions, the 2,4-D degradation efficiency was 75.6% using 2D and 93.5% using 3D electrode processes. The percentage contribution of each controllable factor was also determined. The pH of the solution was identified as the most influential factor, and its percentage contribution value was up to 39.9% and 40.4% for 2D and 3D electrode processes, respectively. Considering the parameters of the kinetics, it was found that the degradation of 2,4-D and removal of COD using the G/β-PbO2 electrode obey the pseudo-first order kinetics. In addition, the mineralization pathway of 2,4-D at G/β-PbO2 electrode was proposed. The results also demonstrated that the 3D electrode process with G/β-PbO2 anode can be considered as a useful method for degradation and mineralization of 2,4-D herbicides from aqueous solution.

Optimization of process parameters using the Taguchi method, electrochemical degradation and electrochemical degradation mechanism of 2,4-D herbicide using 2D and 3D reactors with G/β-PbO2 anode were investigated.  相似文献   
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The current literature lacks strong guidelines regarding surgical management of patients with aspirin-exacerbated respiratory disease (AERD), who present with the clinical triad of chronic rhinosinusitis with nasal polyposis (CRSwNP), bronchial asthma, and aspirin/nonsteroidal anti-inflammatory drug intolerance. To further define the effectiveness of sinus surgery in treating AERD patients, this review article discusses current evidence regarding outcomes associated with more extensive surgery, the benefits of frontal sinus surgery on polyposis, and the role of Draf III intervention. Numerous studies suggest that Draf III frontal sinusotomy may be an efficacious early intervention due to increased neo-ostial patency and subsequent distribution of topical therapies. Future studies that further investigate the efficacy and safety of extensive surgery in AERD patients are warranted.  相似文献   
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Di(2-ethylhexyl) phthalate (DEHP) is used to make polyvinyl chloride (PVC) plastic tubing soft and flexible. Animal data show that adverse effects of DEHP exposure may include reduced fertility, reduced sperm production in males, and ovarian dysfunction in females. Known treatments that involve high DEHP exposures are blood exchange transfusions, extracorporeal membrane oxygenation (ECMO), and cardiovascular surgery. Although potential exposure to DEHP in ECMO patients is significant, the exposure has not been associated with short-term toxicity. To evaluate long-term toxicity, we undertook a study of neonatal ECMO survivors to assess their onset of puberty and sexual maturity. We evaluated 13 male and 6 female subjects at 14-16 years of age who had undergone ECMO as neonates. All subjects had a complete physical examination including measurements for height, weight, head circumference, and pubertal assessment by Tanner staging. The testicular volume and the phallic length were measured in male participants. Laboratory tests included thyroid, liver, and renal function as well as measurements of luteinizing hormone, follicle-stimulating hormone, testosterone for males, and estradiol for females. Except for one patient with Marfan syndrome, the rest had normal growth percentile for age and sex. All had normal values for thyroid, liver, and renal functions. Sexual hormones were appropriate for the stage of pubertal maturity. Our results indicate that adolescents exposed to significant quantities of DEHP as neonates showed no significant adverse effects on their physical growth and pubertal maturity. Thyroid, liver, renal, and male and female gonadal functions tested were within normal range for age and sex distribution. Key Words: DEHP, ECMO, toxicity.  相似文献   
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2,4-Dichlorophenoxyacetic acid (2,4-D) is one of the most commonly used herbicides in the world. In this work, the electro-catalytic degradation of 2,4-D herbicide from aqueous solutions was evaluated using three anode electrodes, i.e., lead dioxide coated on stainless steel 316 (SS316/β-PbO2), lead dioxide coated on a lead bed (Pb/β-PbO2), and lead dioxide coated on graphite (G/β-PbO2). The structure and morphology of the prepared electrodes were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The process of herbicide degradation was monitored during constant current electrolysis using cyclic voltammetry (CV). In this study, the experiments were designed based on the central composite design (CCD) and were analyzed and modeled by response surface methodology (RSM) to demonstrate the operational variables and the interactive effect of three independent variables on 3 responses. The effects of parameters including pH (3–11), current density (j = 1–5 mA cm−2) and electrolysis time (20–80 min) were studied. The results showed that, at j = 5 mA cm−2, by increasing the reaction time from 20 to 80 min and decreasing the pH from 11 to 3, the 2,4-D herbicide degradation efficiency using SS316/β-PbO2, Pb/β-PbO2 and G/β-PbO2 anode electrodes was observed to be 60.4, 75.9 and 89.8%, respectively. Moreover, the results showed that the highest COD and TOC removal efficiencies using the G/β-PbO2 electrode were 83.7 and 78.5%, under the conditions pH = 3, electrolysis time = 80 min and j = 5 mA cm−2, respectively. It was also found that G/β-PbO2 has lower energy consumption (EC) (5.67 kW h m−3) compared to the two other studied electrodes (SS316/β-PbO2 and Pb/β-PbO2). The results showed a good correlation between the experimental values and the predicted values of the quadratic model (P < 0.05). Results revealed that the electrochemical process using the G/β-PbO2 anode electrode has an acceptable efficiency in the degradation of 2,4-D herbicide and can be used as a proper pretreatment technique to treat wastewater containing resistant pollutants, e.g., phenoxy group herbicides (2,4-D).

Optimization of process parameters by the CCD method and electrocatalytic degradation and the electrochemical degradation mechanism of 2,4-D using modified electrode anodes were investigated.  相似文献   
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The aim of this study was to translate and adapt to Persian, and to assess psychometric properties of the Questionnaire of Cognitive Schema Activation in Sexual Context (QCSASC). A total of 265 Iranian participants (121 women and 144 men) were recruited for this study. A principal component analysis (PCA) with varimax rotation and subsequent confirmatory factor analysis revealed a best fitting five-factor structure similar to the original QCSASC: Incompetence, Undesirability, Abandon/Rejection, Powerless/Helpless, and Difference. However, in the Iranian sample, the original Self-Depreciation dimension was included in the Incompetence and Undesirability factors. An Abandon/Rejection dimension was also evident, and may be explained by cultural, social, and religious factors in the Iranian culture. Additionally, reliability analysis has supported the internal consistency (adequate Cronbach's alpha values) and temporal stability (test–retest reliability) of the QCSASC in an Iranian sample. The findings suggest the adequacy of the Persian version of the QCSASC to assess cognitive schemas in sexual context among Iranian men and women.  相似文献   
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