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31.
Substituting an ion of different size from that of the host element introduces lattice strain and defects. However, this mismatch may be significantly reduced by substituting an additional ion with a compensating size relative to the dopant. Such a double substitution might offer better solubility irrespective of the local distortions as well as the formation of defects in the valence states. Fe-substituted ZnO has been widely reported with conflicting results primarily arising from lack of chemical and structural homogeneity originating from preparation techniques, compositional fluctuations, and equivocal comprehension of actual solubility limits of the dopants. In this study, Ag ion has been incorporated in Fe-substituted ZnO to compensate the ionic size of Zn1−x[Fe0.8Ag0.2]xO (0 ≤ x ≤ 0.03125) by determining the solubility limit of the homogeneous material and their corresponding structural, mechanical, optical and magnetic properties have been investigated thoroughly. Co-substitution rearranges the lattice and leads to better crystal structures with tunable properties related to the amount of substitution.

Substituting an ion of different size from that of the host element introduces lattice strain and defects.  相似文献   
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Clinical Rheumatology - A project aimed to develop and deliver a clinical training course in Accra, Ghana, to increase patient access to physicians trained in the diagnosis, treatment and...  相似文献   
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Annals of Hematology - COVID-19 is a global pandemic triggered by the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 entry point involves the interaction with...  相似文献   
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This report describes the case of a young man who presented with right bundle-branch block and second degree atrioventricular block; intermittent episodes of Wenckebach periods were recorded. His bundle electrograms demonstrated progressive prolongation of the HV interval followed by block occurring distal to His. This report emphasizes the fact that the Wenckebach phenomenon as a manifestation of the distal conducting system disease can occur in young adults. The observations lend credence to the concept that Lenègre's disease can occur in young people.  相似文献   
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Amoebiasis is a parasitic infectious disease caused by the enteric protozoan Entamoeba histolytica, a leading basis of deaths accounted to parasites, succeeding malaria and schistosomiasis. Conventional treatment methodologies used to deal with amoebiasis mainly rely on the administration of anti‐amoebic compounds and vaccines but are often linked with substantial side‐effects on the patient. Besides, cases of development of drug resistance in protozoans have been recorded, contributing further to the reduction in the efficiency of the treatment. Loopholes in the efficacious management of the disease call for the development of novel methodologies to manage amoebiasis. A way to achieve this is by targeting the essential metabolic processes of ‘encystation’ and ‘excystation’, and the associated biomolecules, thus interrupting the biphasic life cycle of the parasite. Technologies like the CRISPR‐Cas9 system can efficiently be exploited to discover novel and essential molecules that regulate the protozoan's metabolism, while efficiently manipulating and managing the known drug targets, leading to an effective halt and forestall to the enteric infection. This review presents a perspective on these essential metabolic processes and the associated molecules that can be targeted efficaciously to prevent the transmission of amoebiasis, thus managing the disease and proving to be a fruitful endeavour.  相似文献   
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The work demonstrated a successful synthesis of nitric oxide (NO)-releasing material and its antibacterial effect on Gram-negative Escherichia coli (E. coli), Gram-positive Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA). The polymeric support composed of thermosensitive Pluronic F68 having good biocompatibility and branched polyethylenimine (BPEI) housed N-diazeniumdiolates (NONOates) which could store and release NO under appropriate physiological condition. The developed F68–BPEI–NONOates releases a sufficient amount of NO under physiological condition to elicit effective killing of E. coli, S. aureus and MRSA. The antibacterial ability of the released NO was compared to untreated control or unmodified F68 polymer by using confocal microscopy; F68–BPEI–NONOates demonstrated excellent antibacterial activity with in vitro low cytotoxicity. TEM investigation also revealed the destruction of bacteria membrane caused by NO. The effectiveness of F68–BPEI–NONOates against resistant strains such as MRSA provides a very simple but highly efficient strategy to combat drug-resistant bacterial infections.  相似文献   
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Annals of Nuclear Medicine - 68Ga-DOTA-NaI-octreotide (DOTANOC) is a promising new alternative to 18F-fluorodeoxyglucose (FDG) for imaging inflammation in cardiac sarcoidosis. The aim of the study...  相似文献   
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