Partial hydronephrosis due to pressure from normal renal arteries.

The above work is believed to present direct evidence that the Ph' chromosome is present in the erythroid as well as in the myeloid cell series. Several workers (Tough et al., 1963; Trujillo and Ohno, 1963 ; Whang et al., 1963) have, on the basis of good circumstantial evidence, postulated the probable involvement of megakaryoblasts.