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Poly(3,4‐ethylenedioxythiophene) (PEDOT) films have been electropolymerized from an aqueous micellar solution encompassing the monomer (EDOT) and the moieties sodium dodecyl sulfate (SDS) and lithium triflate. The presence of these anionic dopants in the polymer matrix and a doping level of 0.26 have been confirmed by X‐ray photoemission and electron paramagnetic resonance (EPR) spectroscopy. The hydrophobic micellar core encompassing the monomer orchestrates the growth of a uniform homogeneous polymer deposit as electron microscopy and atomic force microscopy studies reveal the film to be composed of a continuous interlinked network of quasi‐spherical grains (50–150 nm in dimensions) and pores alongwith a low surface roughness. The film exhibits a large coloration efficiency of 153 cm2 · C?1 and a transmission modulation of 62% (λ = 632.8 nm), which are manifestations of the open ion‐permeable morphology. The Q(inserted/extracted) ratio ranges between 1.2 and 1.4 when cycled back and forth between the clear and blue states 2 500 times, thereby affirming the suitability of these films for practical electrochromic smart windows.

  相似文献   

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This case report is on a very rare case of giant anal canal ulcer with rectal prolapse causing total faecal incontinence. An elderly patient in her eighties presented to the emergency department with complaints of a mass protruding thorough anus along with fresh rectal bleeding. Examination revealed a large ulcer measuring 6 cm × 8 cm involving the entire anal canal with rectal prolapse. Here, we discuss the management of this patient with a rare cause of giant anal canal ulceration.  相似文献   
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Angiotensin II (Ang II) induces protein synthesis and hypertrophy through arachidonic acid (AA)- and redoxdependent activation of the serine-threonine kinase Akt/PKB in mesangial cells (MCs). The role of NAD(P)H oxidase component p22( phox ) was explored in this signaling pathway and in Ang II-induced expression of the extracellular matrix protein fibronectin. Ang II causes activation of Akt/PKB and induces fibronectin protein expression, effects abrogated by phospholipase A(2) inhibition and mimicked by AA. Ang II and AAalso elicited an increase in fibronectin expression that was reduced with a dominant negative mutant of Akt/PKB. Exposure of the cells to hydrogen peroxide stimulates Akt/PKB activity and fibronectin synthesis. The antioxidant N-acetylcysteine abolished Ang II- and AA-induced Akt/PKB activation and fibronectin expression. Western blot analysis revealed high levels of p22( phox ) in MCs. Antisense (AS) but not sense oligonucleotides for p22( phox ) prevented ROS generation in response to Ang II and AA. AS p22( phox ) inhibited Ang II- or AA-induced Akt/PKB as well as protein synthesis and fibronectin expression. These data provide the first evidence, in MCs, of activation by AAof a p22( phox )-based NAD(P)H oxidase and subsequent generation of ROS. Moreover, this pathway mediates the effect of Ang II on Akt/PKB-induced protein synthesis and fibronectin expression.  相似文献   
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Objective: This study aims to evaluate the change in serum anti-Mullerian hormone (AMH) levels in patients with morbid obesity undergoing bariatric surgery for weight loss.

Material and methods: In this prospective observational study, 75 patients of reproductive age (20–35 years) undergoing bariatric surgery for morbid obesity were followed up after six months to determine the changes in weight, Body Mass Index (BMI), menstrual pattern and serum AMH. The results were further studied on basis of pre operative classification of patients in polycystic ovary syndrome (PCOS) and non-PCOS group.

Result: The serum AMH levels were statistically higher in patients of PCOS group pre operatively and at the end of six months in comparison to non-PCOS patients. The AMH values reduced post operatively in both groups significantly so much in the values though not significant statistically. Non-PCOS patients had lower AMH values pre operatively and showed a trend towards reducing ovarian reserve after six months. The overall change in AMH values in both groups was statistically significant as was the normalization of menstrual irregularity.

Conclusion: Morbidly obese patients with PCOS appear to benefit from bariatric surgery both in terms of regularization of menstrual function and normalization of serum AMH values.  相似文献   

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Objective: To determine whether post-extubation respiratory support via nsNIPPV decreases the need for mechanical ventilation (MV) compared to nasal continuous positive airway pressure (NCPAP) in preterm infants with respiratory distress syndrome (RDS).

Methods: In this randomized, controlled, open, prospective, single-center clinical trial, we randomly assigned preterm ventilated infants with RDS to either nsNIPPV or NCPAP after extubation. The primary outcome, extubation failure, was defined by pre-specified failure criteria in the 72 hours after extubation.

Results: A total of 63 preterm ventilated infants were randomized to receive either nsNIPPV (n?=?31) or NCPAP (n?=?32). Extubation failure occurred in six (19.3%) of nsNIPPV group compared with nine (28.12%) of NCPAP group and was statistically not significant (p?=?0.55). The duration of NIV was significantly lower in nsNIPPV group as compared to NCPAP group (40.4?±?39.3 hours versus 111.8?±?116.4 hours, p?=?0.003). The duration of supplementary oxygen was significantly lower in nsNIPPV versus NCPAP group (84.9?±?92.1 hours versus 190.1?±?140.5 hours, p?=?0.002). The rates of BPD in nsNIPPV group (2/29, 6.9%) were significantly lower than in NCPAP group (9/28, 32.14%) (p?=?0.02).

Conclusions: Compared to NCPAP, nsNIPPV appears to be a feasible mode of extubation in preterm infants with significant beneficial effects of reduced duration of NIV support, supplementary oxygen and decreased rates of BPD.  相似文献   
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