The design, development and documentation of software. See software engineer, systems analysis & design, programming, object-oriented programming, software metrics, CASE and Systemantics.
Overview. Posttransplant lymphoproliferative disease (PTLD) is an unusual entity that has many features of an immune system malignancy. It is characterized by uncontrolled proliferation of lymphoid lineage cells (typically B cells, rarely non-B lineage) in a context of posttransplant immunosuppression.
Partial thromboplastin time (PTT) is a blood test that looks at how long it takes for blood to clot. It can help tell if you have bleeding or clotting problems.