Undesirability of Replacing One Left-Sided Cardiac Valve with a Mechanical Prosthesis and Another with a Bioprosthesis

Patellar Fractures in Children. A Case Report in a Seven Year Old Girl

41-year-old Man With Pulmonary Embolism 5 Months After Covid19

The Change of Children and Adolescents Growth and Development in 20 Years in Shenmu City, China