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European Journal of Clinical Microbiology & Infectious Diseases - This study determined the carriage rates and antimicrobial resistance (AMR) genes of enterococci from...  相似文献   
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The laser shock peening (LSP) process using a Q-switched pulsed laser beam for surface modification has been reviewed. The development of the LSP technique and its numerous advantages over the conventional shot peening (SP) such as better surface finish, higher depths of residual stress and uniform distribution of intensity were discussed. Similar comparison with ultrasonic impact peening (UIP)/ultrasonic shot peening (USP) was incorporated, when possible. The generation of shock waves, processing parameters, and characterization of LSP treated specimens were described. Special attention was given to the influence of LSP process parameters on residual stress profiles, material properties and structures. Based on the studies so far, more fundamental understanding is still needed when selecting optimized LSP processing parameters and substrate conditions. A summary of the parametric studies of LSP on different materials has been presented. Furthermore, enhancements in the surface micro and nanohardness, elastic modulus, tensile yield strength and refinement of microstructure which translates to increased fatigue life, fretting fatigue life, stress corrosion cracking (SCC) and corrosion resistance were addressed. However, research gaps related to the inconsistencies in the literature were identified. Current status, developments and challenges of the LSP technique were discussed.  相似文献   
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The anti-Trypanosoma brucei brucei activity in vitro and in vivo of a lactone-rich fraction of Vernonia blumeoides leaves (VBLF) and its potential in alleviating trypanosome-induced anemia and organ damage were investigated. Gas chromatography–mass spectrometry (GC–MS) analysis of VBLF revealed the presence of a number of lactone-containing compounds. In an in vitro study, VBLF showed concentration-dependent activity and was further used to treat T. brucei brucei-infected rats. The VBLF treatments, especially at 300 mg/kg body weight (BW), significantly (P < 0.05) kept the parasites reduced during the entire experimental period compared with the infected untreated group. At the end of the experiment, the trypanosome-induced anemia and hepatic damage were significantly (P < 0.05) alleviated in all the VBLF treatment groups, but renal damage was only prevented in the 200 and 300 mg/kg BW treatment groups. Furthermore, the trypanosome-induced increase in the relative weights of liver, spleen and kidney were significantly (P < 0.05) alleviated by the 300 mg/kg BW VBLF treatment. It was concluded that orally administered VBLF, especially at 300 mg/kg BW, possessed antitrypanosomal activity and could alleviate parasite-induced anemia and organ damage.  相似文献   
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An automated radiosynthesis of carbon-11 positron emission tomography radiotracer [11C]UCB-J for imaging the synaptic density biomarker synaptic vesicle glycoprotein SV2A was established using Synthra RNPlus synthesizer. Commercially available trifluoroborate UCB-J analogue was used as a radiolabelling precursor, and the desired radiolabelled product was isolated in 11 ± 2% (n = 7) nondecay corrected radiochemical yield and formulated as a 10% EtOH solution in saline with molar activities of 20 to 100 GBq/μmol. The method was based upon the palladium(0)-mediated Suzuki cross-coupling reaction and [11C]CH3I as a radiolabelling synthon. The isolated product was cGMP compliant as demonstrated by the results of quality control analysis.  相似文献   
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GeroScience - The neuroprotective effects of pituitary adenylate cyclase-activating polypeptide (PACAP) have been shown in numerous in vitro and in vivo models of Parkinson’s disease (PD)...  相似文献   
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Introduction:Human Immunodeficiency Virus (HIV) infection remains prevalent co-morbidity, and among fracture patients. Few studies have investigated the role of exercise interventions in preventing bone demineralization in people who have fractures and HIV. If exercise exposed, HIV-infected individuals may experience improved bone health outcomes (BMD), function, quality of life (QoL). The study will aim to assess the impact of home based exercises on bone mineral density, functional capacity, QoL, and some serological markers of health in HIV infection among Nigerians and South Africans.Methods and design:The study is an assessor-blinded randomized controlled trial. Patients managed with internal and external fixation for femoral shaft fracture at the study sites will be recruited to participate in the study. The participants will be recruited 2 weeks post-discharge at the follow-up clinic with the orthopaedic surgeon. The study population will consist of all persons with femoral fracture and HIV-positive and negative (HIV-positive medically confirmed) aged 18 to 60 years attending the above-named health facilities. For the HIV-positive participants, a documented positive HIV result, as well as a history of being followed-up at the HIV treatment and care center. A developed home based exercise programme will be implemented in the experimental group while the control group continues with the usual rehabilitation programme. The primary outcome measures will be function, gait, bone mineral density, physical activity, and QoL.Discussion:The proposed trial will compare the effect of a home-based physical exercise-training programme in the management of femoral fracture to the usual physiotherapy management programmes with specific outcomes of bone mineral density, function, and inflammatory markers.Trial registration:The study was prospectively registered with the Pan African Clinical Trials Registry (Reference number – PACTR201910562118957) on October 21, 2019. (https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=9425).  相似文献   
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Objective: To determine if there was any difference in SpO2 readings during exchange blood transfusion (EBT).Methods: A prospective cross-sectional study of neonates with severe neonatal jaundice requiring EBT was conducted. Oxygen saturation was recorded before, immediately and 15 minutes after EBT by using a pulse oximeter. Results: This study included 30 neonates with 20 males and 10 females. The age ranged from 1 to 12 days with a mean of (5.4 ± 2.9) days. Pre-EBT SpO2 ranged from 90% to 98% with a mean value of (94.3 ± 2.2)%; SpO2 in the end of EBT ranged from 85% to 99% with a mean value of (94.1 ± 3.2)%; SpO2 at 15 minutes after EBT ranged from 77% to 99% with a mean value of (94.8 ± 4.1)%. There was no significant difference between SpO2 values at onset of EBT and either immediately or 15 minutes after EBT (P=0.770 and 0.422, respectively). SpO2 showed no significant difference between neonates who were infused with blood of different storage times (<24 h or ≥24 h) at the onset of EBT (P=0.584), immediately (P>0.999) and 15 minutes after EBT (P=0.887). Besides, SpO2 values were compariable in neonates with hematocrit <45% or ≥45% at the onset of EBT (P=0.284), immediately (P=0.118) and 15 minutes after EBT (P=0.868). Conclusions: EBT does not affect SpO2 in neonates.  相似文献   
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