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11.

Background:

Tertiary pediatric hospitals usually provide excellent clinical services, but such centers have a lot to do for educational perfection.

Objectives:

This study was performed to address under-graduate educational deficits and find feasible solutions.

Patients and Methods:

This cross-sectional study was done in a target population of 77 sixth year undergraduate medical students (response rate = 78%) who spent their 3-month pediatric rotation in the Children’s Medical Center, the Pediatrics Center of Excellence in Tehran, Iran. The Dundee ready educational environment measure (DREEM) instrument was used for assessing educational environment of this subspecialized pediatric hospital.

Results:

Among 60 students who answered the questionnaires, 24 were male (40%). Participants’ age ranged from 23 to 24 years. The mean total score was 95.8 (48%). Comparison of scores based on students’ knowledge showed no significant difference. Problematic areas were learning, academic self-perception, and social self-perception.

Conclusions:

Having an accurate schedule to train general practitioner, using new teaching methods, and providing a non-stressful atmosphere were suggested solutions.  相似文献   
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Metabolic Brain Disease - Alzheimer’s disease is the most common neurodegenerative disease associated with deposition of amyloid-beta and the increased oxidative stress. High free radical...  相似文献   
13.

Background:

Bowel function has been reported to be adversely affected following surgery in cases of Hirschsprung. We retrospectively studied both the clinical outcome and bowel function status following surgery in patients diagnosed with Hirschprung''s disease (HD). 161 cases, who underwent pull-through operations for HD in Sheikh Pediatric Tertiary Centre, Mashhad, Iran. The specified time bracket spanned between 2006 and 2011.

Materials and Methods:

Data was extracted from Health Information System with the aim of investigating patients for both short and long-term gastrointestinal (GI) complications after surgery bases in addition to the concurrence of any associated anomalies. Three main procedures were analysed in this respect (Swenson, Duhamel and Soave).

Results:

In a study of 96 (59%) boys and 65 (40.3%) girls, mortality rate was reported to be 15.5% (15 males and 10 females). A considerable majority of almost three fourths were detected with both early and late GI complications after surgery. The latter mainly included constipation (30.8%), incontinence (19.8%), enterocolitis (8%), diarrhea (11%) in a declining order of incidence. Down syndrome and others HD-associated anomalies were detected in 3.7% and 24.3% of cases respectively.

Conclusions:

Constipation and foecal incontinence were the most prevalent postoperative complications, which were reported almost as frequent in other studies. Yet, Enterocolitis, was reported slightly less in prevalence. Also mortality rates were considerably higher, compared to developed nations.Key words: Bowel function, constipation, foecal incontinence, Hirschsprung''s disease  相似文献   
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In this study, a novel Mn(iii)–Schiff base complex was synthesized and characterized. The structure of this complex was determined to be a deformed octahedral coordination sphere by single-crystal X-ray diffraction analysis. The Mn(iii)–Schiff base complex was supported on silica-coated iron magnetic nanoparticles via axial coordination by one-step complex anchoring to produce a heterogenized nanocatalyst. After this, the complex was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), and powder X-ray diffraction (XRD). Moreover, atomic absorption spectroscopy was used to determine the amount of the loaded metal. The heterogenized nanocatalyst effectively catalyzed the oxidation of a broad range of sulfides and alkenes with H2O2 in the presence of a glassy carbon electrode, applying voltage to the reaction mixture. The results showed that the application of a potential to the reaction mixture could significantly decrease the reaction time when compared with the case of similar chemical oxidation reactions. In addition, an excellent value of turnover frequency (17 750 h−1) was achieved for the electrochemical oxidation of styrene. Moreover, the nanocatalyst showed good recoverability without significant loss of its activity within six successive runs in the electrochemical oxidation of methyl phenyl sulfide and cyclooctene. The electrochemical properties and stability of Fe3O4@SiO2-[MnL(OAc)] were investigated by cyclic voltammetry measurements and chronoamperometry technique.

A Mn–Schiff base complex supported on silica-coated iron magnetic nanoparticles was used for the electrochemical oxidation of sulfides and alkenes.  相似文献   
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Angiotensin II (Ang II) might induce pro‐inflammatory effects directly in the vascular wall independently of its haemodynamic effects. The aim of our study was to investigate the putative direct pro‐inflammatory and vasomotor effects of Ang II and compare to those of lipopolysaccharides (LPS) in mouse isolated mesenteric resistance‐sized arteries (MRA) supported by experiments in cultured human primary endothelial and vascular smooth muscle cells. Results showed that 24‐hr organ culture of mouse MRA with 10 nM Ang II had, unlike 100 ng/mL LPS, no effects on IL‐6 or MCP‐1 secretion, VCAM1 mRNA expression or endothelial function, while Ang II significantly decreased maximal vasomotor responses to phenylephrine. In support, 24‐hr organ culture of mouse MRA significantly suppressed Agtr1a mRNA and augmented Tlr4 mRNA along with attenuated vasomotor responses to Ang II. Moreover, contrary to LPS and TNF‐α, Ang II and [Sar1]‐Ang II had no concentration‐ or time‐dependent effects on IL‐6 and MCP‐1 secretion in human umbilical vein endothelial cells (HUVEC) and human aortic smooth muscle cells (HASMC). AGTR1 or AGTR2 mRNA expression was undetectable in HUVEC, whereas HASMC expressed only AGTR1 mRNA. In summary, contrary to previous studies and the observed effects of LPS, we could not demonstrate direct vascular pro‐inflammatory effects of Ang II ex vivo or in vitro. As indicated by our results, down‐regulation or desensitization of AT1R during culture may explain our findings.  相似文献   
18.
Aims/IntroductionIn recent years, mesenchymal cellular therapies have received much attention in the treatment of diabetes. In this meta‐analysis, we aimed to evaluate the efficacy of mesenchymal stem cell therapy in type 2 diabetes mellitus patients.Materials and MethodsA comprehensive literature search was carried out using PubMed, Scopus, Web of Science and Central databases. A total of 1,721 articles were identified, from which nine full‐text clinical trials were qualified to enter the current meta‐analysis. The assessment groups included patients with type 2 diabetes, and levels of C‐peptide, glycosylated hemoglobin and insulin dose were analyzed before and after mesenchymal stem cell infusion. Data analysis was carried out in Stata version 11, and the Jadad Score Scale was applied for quality assessment.ResultsChanges in levels of C‐peptide after mesenchymal stem cell therapy were: standardized mean difference 0.20, 95% confidence interval −0.61 to 1.00, glycosylated hemoglobin levels were: standardized mean difference −1.45, 95% confidence interval −2.10 to −0.79 and insulin dose were: standardized mean difference −1.40, 95% confidence interval −2.88 to 0.09.ConclusionsThis meta‐analysis of prospective studies showed associations between mesenchymal stem cell therapy and control of glucose level in patients with type 2 diabetes.  相似文献   
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Several attenuated and non-pathogenic bacterial species have been demonstrated to actively target diseased sites and successfully deliver plasmid DNA, proteins and other therapeutic agents into mammalian cells. These disease-targeting bacteria can be employed for targeted delivery of therapeutic and imaging cargos in the form of a bio-hybrid system. The bio-hybrid drug delivery system constructed here is comprised of motile Escherichia coli MG1655 bacteria and elliptical disk-shaped polymeric microparticles. The transport direction for these vehicles can be controlled through biased random walk of the attached bacteria in presence of chemoattractant gradients in a process known as chemotaxis. In this work, we utilize a diffusion-based microfluidic platform to establish steady linear concentration gradients of a chemoattractant and investigate the roles of chemotaxis and geometry in transport of bio-hybrid drug delivery vehicles. Our experimental results demonstrate for the first time that bacterial chemotactic response dominates the effect of body shape in extravascular transport; thus, the non-spherical system could be more favorable for drug delivery applications owing to the known benefits of using non-spherical particles for vascular transport (e.g. relatively long circulation time).  相似文献   
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