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41.
Amira Ezzat Khamis Amine Mohamed Omar Mohamed Helal Wafaa Mohamed Kamel Bakr 《GMS Krankenhaushygiene interdisziplin?r》2014,9(2)
Aim: Catheter associated urinary tract infections (CAUTI) are the most common hospital-acquired infection in ICUs. The aim of this study was to estimate the effectiveness of an intervention program by implementing urinary catheter bundle elements to reduce the CAUTI frequency in an ICU. Methods: The intervention study was conducted over a period of 6 months. During a pre-intervention phase, the base line catheter associated CAUTI incidence rates were determined and compared with the incidence rates during the post-intervention phase. The compliance of health care staff with urinary catheter bundle elements was also measured. The implemented CAUTI prevention bundle consisted of hand hygiene, wearing personal protective equipment, use of disposable gloves, cleansing of urethral meatus prior to catheter insertion using sterile saline, assessment of catheter need, aseptic urine sampling technique, and correct draining bag positioning.Results: During the study period, 55 out of 77 patients were diagnosed with a CAUTI. The mean CAUTI incidence rate for the pre-intervention period was 90.12/1,000 catheter days and for the post intervention phase 65.69/1,000 catheter days. The CAUTIs rate was inversely proportional to insertion bundle elements and maintenance bundle elements compliance rate. This negative relationship was statistically significant only with maintenance bundle elements (p=0.042) (rs=–0.828). The compliance rate of the ICU nurses to the bundle elements was raised to 100% during the last 2 months of the post intervention phase.Conclusion: Increased compliance to recommended catheter associated urinary tract infections preventive practices reduced the incidence of CAUTI in an ICU unit. It is simple and effective and is recommended as a part of patient safety culture. 相似文献
42.
Amir Segev Adva S Rubin Hila Abush Gal Richter-Levin Irit Akirav 《Neuropsychopharmacology》2014,39(4):919-933
Most psychiatric disorders are characterized by emotional memory or learning disturbances. Chronic mild stress (CMS) is a common animal model for stress-induced depression. Here we examined whether 3 days of treatment using the CB1/2 receptor agonist WIN55,212-2 could ameliorate the effects of CMS on emotional learning (ie, conditioned avoidance and extinction), long-term potentiation (LTP) in the hippocampal-accumbens pathway, and depression-like symptoms (ie, coping with stress behavior, anhedonia, and weight changes). We also examined whether the ameliorating effects of WIN55,212-2 on behavior and physiology after CMS are mediated by CB1 and glucocorticoid receptors (GRs). Rats were exposed to CMS or handled on days 1–21. The agonist WIN55,212-2 or vehicle were administered on days 19–21 (IP; 0.5 mg/kg) and behavioral and electrophysiological measures were taken on days 23 and 28. The CB1 receptor antagonist AM251 (IP; 0.3 mg/kg) or the GR antagonist RU-38486 (IP; 10 mg/kg) were co-administered with WIN55,212-2. Our results show that CMS significantly modified physiological and behavioral reactions, as observed by the impairment in avoidance extinction and LTP in the hippocampal-accumbens pathway, and the alterations in depression-like symptoms, such as coping with stress behavior, weight gain, and sucrose consumption. The most significant effect observed in this study was that 3 days of WIN55,212-2 administration prevented the CMS-induced alterations in emotional memory (ie, extinction) and plasticity. This effect was mediated by CB1 receptors as the CB1 receptor antagonist AM251 prevented the ameliorating effects of WIN55,212-2 on extinction and LTP. The GR antagonist RU-38486 also prevented the CMS-induced alterations in extinction and plasticity, and when co-administered with WIN55,212-2, the preventive effects after CMS were maintained. The findings suggest that enhancing cannabinoid signaling could represent a novel approach to the treatment of cognitive deficits that accompany stress-related depression. 相似文献
43.
Reinforced concrete (RC) beams are basic elements used in the construction of various structures and infrastructural systems. When exposed to harsh environmental conditions, the integrity of RC beams could be compromised as a result of various deterioration mechanisms. One of the most common deterioration mechanisms is the formation of different types of corrosion in the steel reinforcements of the beams, which could impact the overall reliability of the beam. Existing classical reliability analysis methods have shown unstable results when used for the assessment of highly nonlinear problems, such as corroded RC beams. To that end, the main purpose of this paper is to explore the use of a structural reliability method for the multi-state assessment of corroded RC beams. To do so, an improved reliability method, namely the three-term conjugate map (TCM) based on the first order reliability method (FORM), is used. The application of the TCM method to identify the multi-state failure of RC beams is validated against various well-known structural reliability-based FORM formulations. The limit state function (LSF) for corroded RC beams is formulated in accordance with two corrosion types, namely uniform and pitting corrosion, and with consideration of brittle fracture due to the pit-to-crack transition probability. The time-dependent reliability analyses conducted in this study are also used to assess the influence of various parameters on the resulting failure probability of the corroded beams. The results show that the nominal bar diameter, corrosion initiation rate, and the external loads have an important influence on the safety of these structures. In addition, the proposed method is shown to outperform other reliability-based FORM formulations in predicting the level of reliability in RC beams. 相似文献
44.
This study involves the novel fabrication of a high responsivity, fast response, and low-cost (UV) photodetector (PD) based on ZnO/Ni nanoparticles deposited on a glass substrate. The ZnO/Ni nanoparticles were synthesized using a polyol process. The structure and the morphology of the samples were characterized by X-ray diffraction (XRD) and Transmission Electron Microscopy (TEM). Optical properties were measured using UV-visible, diffuse reflectance and photoluminescence (PL) spectroscopy. The photodetector exhibited high photoresponse characteristics under 375 nm laser excitation. Our device shows a high responsivity (121 A W−1) with rise time (about 5.52 s) and fall time (about 12 s) at a bias voltage of 1 V. The device exhibits excellent reproducibility and stability characteristics with time. The noise spectra obtained from the UV photodetector were caused by the 1/f noise. The noise-equivalent power (NEP) is 1.08 × 10−9 W. Thus, the polyol process can be a useful and effective method for improving the performance of ZnO/Ni UV photodetectors.This study involves the novel fabrication of a high responsivity, fast response, and low-cost (UV) photodetector (PD) based on ZnO/Ni nanoparticles deposited on a glass substrate. 相似文献
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47.
Zare Mohammad Mehdi Ghram Amine Akbarnejad Ali Soori Rahman Charkhi Sahl Abad Anis Azizi Ghuchan Fatemeh Nunes-Silva Albená 《Sport Sciences for Health》2020,16(1):47-54
Sport Sciences for Health - Purslane supplementation has anti-oxidative, anti-inflammatory, skeletal muscle-relaxant activities. However, it is unknown if the ingestion of purslane will affect the... 相似文献
48.
Abstract Desialylation of platelets results in platelet clearance by the Ashwell-Morrell Receptors (AMR) found on hepatocytes. Studies suggest that oseltamivir phosphate inhibits human sialidases, enzymes responsible for desialylation, extending the lifespan of circulating platelets. We thus evaluated, the effects of oseltamivir on platelet count (PC) following treatment. Of the 385 patients evaluated for influenza, 283 (73.5%) were influenza-infected. Of the 283 infected patients, 241 (85.2%) received oseltamivir (I + O+) while 42 patients did not (I + O-). One hundred two non-infected patients received oseltamivir (I-O+). The two groups receiving oseltamivir (I + O+, I-O+), demonstrated a statistically greater increase in the PC (57.53 ± 93.81, p = .013 and 50.79 ± 70.59, p = .023, respectively) relative to the group that did not (18.45 ± 89.33 × 109/L). The observed increase in PC was statistically similar (p = .61) in both groups receiving oseltamivir (I + O+, I-O+), suggesting that this effect is independent of influenza. Comparing clinical characteristics between responders and non-responders to oseltamivir treatment showed that only duration of oseltamivir treatment (AOR = 1.30, 95% CI 1.05–1.61, p = .015) was associated with a positive PC response. Our findings suggest a correlation between oseltamivir treatment and an increase in PCs. Future studies assessing the possible uses of oseltamivir in medical conditions characterized by diminished or defective thrombopoiesis are warranted. 相似文献
49.
Asma Mahfoudh-Boussaid Kaouther Hadj Ayed Tka Mohamed Amine Zaouali Joan Roselló-Catafau 《Renal failure》2014,36(9):1436-1442
Renal ischemia reperfusion (I/R) injury, which occurs during renal surgery or transplantation, is the major cause of acute renal failure. Trimetazidine (TMZ), an anti-ischemic drug, protects kidney against the deleterious effects of I/R. However its protective mechanism remains unclear. The aim of this study is to examine the relevance of Akt, endothelial nitric oxide synthase (eNOS), and hypoxia inducible factor-1α (HIF-1α) on TMZ induced protection of kidneys against I/R injury. Wistar rats were subjected to 60?min of warm renal ischemia followed by 120?min of reperfusion, or to intraperitoneal injection of TMZ (3?mg/kg) 30?min before ischemia. In sham operated group renal pedicles were only dissected. Compared to I/R, TMZ treatment decreased lactate dehydrogenase (845?±?13 vs. 1028?±?30?U/L). In addition, creatinine clearance and sodium reabsorption rates reached 105?±?12 versus 31?±?11?μL/min/g kidney weight and 95?±?1 versus 68?±?5%, respectively. Besides, we noted a decrease in malondialdehyde concentration (0.33?±?0.01 vs. 0.59?±?0.03?nmol/mg of protein) and an increase in glutathione concentration (2.6?±?0.2 vs. 0.93?±?0.16?µg GSH/mg of protein), glutathione peroxidase (95?±?4 vs. 61?±?3?µg GSH/min/mg of protein), and superoxide dismutase (25?±?3 vs. 11?±?2?U/mg of protein) and catalase (91?±?12 vs. 38?±?9?μmol/min/mg of protein) activities. Parallely, we noted a significant increase in p-Akt, eNOS, nitrite and nitrate (18?±?2 vs. 8?±?0.1?pomL/mg of protein), HIF-1α (333?±?48 vs. 177?±?14?µg/mg of protein) and heme oxygenase-1 (HO-1) levels regarding I/R. TMZ treatment improves renal tolerance to warm I/R. Such protection implicates an activation of Akt/eNOS signaling pathway, HIF-1α stabilization and HO-1 activation. 相似文献
50.
Alaoui Amine Sanaâ Melloul Marouane El Alaoui Moulay Abdelaziz Boulahyaoui Hassan Loutfi Chafiqa Touil Nadia El Fahime Elmostafa 《Virus genes》2020,56(5):582-593
Virus Genes - Species A rotaviruses (RVAs) are a leading cause of diarrhea in children and in the young of a large variety of mammalian and avian host species. The purpose of this study was to... 相似文献