Mammalian stem cells differentiate into several kinds of blood cell within the bone marrow. Granulocytes are derived from stem cells residing in the bone marrow. Diagnosis is by examination of a bone marrow or lymph node biopsy. Tissue deficiency resulting in negative effects in nerve cells, bone marrow, and the skin. Dopamine can also affect immune cells in the spleen, bone marrow, and circulatory system. Wnt signaling also controls tissue regeneration in adult bone marrow, skin and intestine. Lymphocytes are initially generated in the bone marrow. The plasma cells can also form a mass in the bone marrow or soft tissue. All MPNs arise from precursors of the myeloid lineages in the bone marrow. All are used to examine blood or bone marrow samples. Basophils arise and mature in bone marrow. Granulocytes are produced via granulopoiesis in the bone marrow. It may be toxic to bone marrow. B cells enter the bloodstream as "naive" cells produced in bone marrow. Myeloblasts reside extravascularly in the bone marrow.