Abstract For cancer diagnosis. a paramount challenge still exists in the exploring of methods that can precisely discriminate tumor tissues from their surrounding healthy tissues with a high target-to-background signal ratio. Here. we report a NaGdF4@CaCO3-PEG core-shell nanoparticle which has the tumor acidic microenvironment enhanced imaging signals of ultrasound and magnetic resona... https://unitedssports.shop/product-category/bike-parts-handlebars-stems/