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Objective: To evaluate the effectiveness of Judet''s quadricepsplasty for treatment of knee contractures and to identify the effect of local infiltration of epinephrine on blood loss associated with this procedure. Methods: A retrospective cohort study was conducted in which all cases of knee contractures managed with Judet''s quadricepsplasty from 1st January 2009 to 31st December 2013 were included and were divided into two groups. The epinephrine group included patients who were infiltrated with diluted epinephrine (1:400,000) along with xylocaine, around the operative field 15 min prior to the incision time, while the control group did not receive any infiltration. Judet''s outcome, blood loss, drop in hemoglobin and required blood transfusion were noted for all patients and compared between both groups. Results: Most common preceding pathology identified for the development of knee contractures was periarticular fracture while ilizarov application was the most common etiology. Both groups were found similar in all preoperative characteristics except preoperative flexion contracture (p=0.02). All functional outcome measures including Judet''s outcome were similar in both groups. In contrast, duration of surgery (p=0.01), blood loss (p=0.02), drop in hemoglobin (p=0.01) and number of transfusions (p=0.03) were significantly reduced in epinephrine group. Conclusion: Judet''s quadricepsplasty is a useful procedure to increase the range of motion of rigid knees and local infiltration of epinephrine is effective in decreasing the amount of subsequent blood loss and transfusion requirements.  相似文献   
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In Vietnam, a pilot ‘smoke-free hospital’ model was implemented in nine hospitals in 2009–2010 to supply lessons learned that would facilitate a replication of this model elsewhere. This study aimed to assess smoking patterns among health professionals and to detect levels of second-hand smoke (SHS) exposure within hospital premises before and after the ‘smoke-free hospital’ model implementation. A pre- and post-intervention cross-sectional study was conducted in nine purposively selected hospitals. Air nicotine levels were measured using passive nicotine monitors; smoking evidence was collected through on-site observations; and smoking patterns were assessed through interviews with health workers. Despite the ‘smoke-free hospital’ intervention, smoking continued among health-care workers who were former smokers. Specifically, self-reported smoking prevalence significantly decreased post-intervention, but the number of daily cigarettes smoked at workplaces among male health workers remained unchanged. Post-intervention, smoking was more likely to take place outside buildings and cafeterias. However, air nicotine levels in the doctors' lounges and in emergency departments did not change post-intervention. Air nicotine levels at other sites decreased minimally. Tailored tobacco cessation programmes, targeting current smokers and mechanisms to enforce non-smoking, should be established to meet requirements of Vietnam's comprehensive National Tobacco Control Law effective in May 2013.  相似文献   
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AIMS: No antithrombotic therapy has been shown to reduce mortality when used with thrombolytics in acute myocardial infarction (AMI). In the OASIS-6 trial, fondaparinux significantly reduced mortality and reinfarction without increasing bleeding in 12 092 patients with acute ST elevation MI. METHODS AND RESULTS: We report the results of a subgroup analysis in the 5436 patients (45%) receiving thrombolytics. According to local practice, 4415 patients did not have an indication for unfractionated heparin (stratum 1) and 1021 did (stratum 2). Fondaparinux reduced the primary study outcome of death or MI at 30 days [Hazard ratio (HR) 0.79, 95% confidence interval (CI) 0.68-0.92] with consistent reductions in both mortality (HR and CI) and reinfarction (HR and CI). There was a non-significantly lower rate of stroke (HR 0.77, CI 0.48-1.25). The risk of severe bleeding was significantly reduced (HR 0.62, CI 0.40-0.94), and thus the balance of benefit and risk (death, MI and severe haemorrhage) was clearly reduced by fondaparinux (HR 0.77, 95% CI 0.67-0.90). Results were consistent in the two strata, by the different types of thrombolytics and across various time intervals from symptom onset to treatment. CONCLUSION: In STEMI patients treated with thrombolytic agents (predominantly streptokinase), fondaparinux significantly reduced the risk of death, re-MI and severe bleeds.  相似文献   
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European Journal of Clinical Microbiology & Infectious Diseases - The purpose of this study is to determine the role of high (≥ 1.5 mg/L) vancomycin minimum inhibitory concentration...  相似文献   
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Transition metal carbides (TMCs) have recently emerged as competent members among the family of two-dimensional (2D) materials, owing to their promising applications. There are many promising applications of MXenes; however, their magnetic properties lack a wide margin, both experimentally as well as theoretically, which needs to be investigated for potential use in spintronics. In this study, we carried out a comprehensive etching process via selective extraction of Al layers from Nb2AlC-MAX using a wet electrochemical route under well-optimized conditions to obtain fine 2D-Nb2C MXene sheets. Structural analysis using X-ray diffraction (XRD) confirms the effective removal of Al followed by confirmation of a 2D layered structure from morphological analysis using scanning electron microscopy (SEM). Zero-field-cooled (ZFC) and field-cooled (FC) measurements of MAX and MXene at different field strengths were performed using a superconducting quantum interference device (SQUID). Magnetic measurements reveal the paramagnetic nature of Nb2AlC-MAX measured under 5 mT; however, this changes to a clear superconductor-like diamagnetic behavior with a shift of the magnetization from positive to negative values at low temperatures when measured under 5 mT and 10 mT for Nb2C MXene. The diamagnetism, however, is changed to paramagnetism at 100 mT, which shows the existence of critical fields known typically for a type-II superconductor. To gain an insight into this unusual behavior in MXene, density functional theory (DFT) first-principles calculation was also performed in Wein2K software using spin-polarized generalized gradient approximation (sp-GGA). The magnetic moment of the compound is calculated to be negative, which corresponds well with the experimental finding and suggests that the negative magnetic moment originated from the d-orbital of Nb2C. The present report provides a pathway to deeply understanding the existence of superconductivity-like diamagnetic behavior in Nb2C MXene, which is useful for future magnetic applications.

Transition metal carbides (TMCs) have recently emerged as competent members among the family of two-dimensional (2D) materials, owing to their promising applications.

In two-dimensional (2D) materials, magnetism at the nanoscale is at the forefront of many cutting-edge technological applications, such as spintronic devices. Naguib et al. have synthesized a new class of two-dimensional materials, known as MXenes (MnXn+1), discovered in 2011, giving a possibility of magnetism in such 2D materials and their promising uses in spintronic devices.1 These 2D layer structured early transition metal carbides and/or nitrides are known as MXenes, so named to indicate their structural similarities with graphene.2 MXenes are derived from 3D MAX phases (space group P63/mmc) in which “M” is an early transition metal, e.g., Ti, Ta, V, etc.; “A” is mainly a group 13 or group 14 element (group III-A or IV-A), e.g., Si, Al; “X” is a carbide, nitride or can be both; and n = 1, 2, 3 represents the number of layers, forming 211, 312 and 413 phases.3–5 Over the past decade, this new material has gained enormous attention, thus developing an entirely new research field to disclose the properties of the 2D state of this material. The materials in the 2D regime own a cluster of astonishing physical properties as compared to the 3D nature, but intrinsic two-dimensional magnetism has proved to be challenging. As 2D semiconductors have revamped the field of electronics, similarly, magnetism in 2D materials could remodel spintronic devices that can employ a spin degree of freedom.6,7Nb2C MXene was first synthesized by Naguib et al., but they just reported its electrochemical activity as a promising electrode material.4 Further work has been reported in Nb2C with various biomedical applications, energy storage, supercapacitors, and nanoelectronics.9–19 As far as the magnetism in such 2D MXenes is concerned, it remains less investigated, and this research void needs to be filled. Recently, Babar et al. reported the observation of superconductivity in as-prepared powdered Nb2C for the first time, with the highest onset transition temperature Tc,onset = 12.5 K among the MXene family. However, the authors did not discuss the magnetic nature of the parent Nb2AlC MAX itself and did not reason for the presence of unusual magnetic effects in MXene.8 MXenes are favorable members of 2D magnetism, and different magnetic natures are computationally predicted in various carbide and nitride MXenes.7,20 The existence of novel room-temperature ferromagnetic order in doped MXene and the coexistence of different magnetic phases in MXene, along with experimental evidence, indicate its potential of hosting diverse magnetic natures.21,22 Considerable research has been focused on these 2D structures due to their importance and favorable applications, such as spintronics. MXene could provide a vast platform for exploring the magnetic properties and is one of the best candidates that can host superconductivity as compared to other members of the 2D family. Experimental studies are generally dependent upon numerous variables, thus affecting the research pace. However, density functional theory-based first principles calculation and theoretical simulations are a successful way to examine and foresee the properties of low-dimensional materials. This provoked us to theoretically explore superconductivity in Nb2C and their validation through superconductivity measurements of experimentally synthesized Nb2C MXene. In this work, we report a systematic etching mechanism of Nb2C MXene to obtain fine 2D sheets via a chemical etching route using hydrofluoric (HF) acid. Structural and morphological studies using the X-ray diffraction technique (XRD), scanning electron microscopy (SEM) and elemental analysis by energy-dispersive X-ray spectroscopy (EDX) show the effective removal of Al from the parent 3D-Nb2AlC MAX, thus revealing an accordion-like sheet structure. Optical analysis indicates a significant reduction in bandgap after chemical etching. Magnetic properties were carried out to observe the signatures of superconductivity (a perfect diamagnetic state, negative magnetic moment) and its magnetic nature at room temperature. To study the magnetic nature of as-prepared powder-form Nb2C, density functional theory (DFT) first principles calculation was carried out through Wein2K using spin-polarized generalized gradient approximation (sp-GGA). The magnetic moment of the compound is calculated to be −0.00485, which although but small is important, as the value is negative, which is an indication of the presence of diamagnetism in Nb2C. Here, the detailed chemical etching process, magnetic properties of Nb2AlC MAX and its effect on magnetic phase of Nb2C MXene, and the density functional theory calculation are reported, which were not discussed by Babar et al. in ref. 8.  相似文献   
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