The central paradigm of vaccination is to generate resistance to infection by a specific pathogen when the vacinee is re-exposed to that pathogen. This paradigm is based on two fundamental characteristics of the adaptive immune system. specificity and memory. These characteristics come from the clonal specificity of T and B cells and the long-term survival of previously-encountered me... https://www.roneverhart.com/MagnaFlow-2001-2005-Honda-Civic-Street-Series-Cat-Back-Performance-Exhaust-System/