Display substrate and display apparatus

A display substrate comprising a plurality of circuit units constituting a plurality of unit rows and a plurality of unit columns, wherein at least one of the circuit units comprises a pixel drive circuit configured to output a drive current to a light emitting device connected to the pixel drive circuit;

• the pixel drive circuit at least comprises a second transistor as a compensation transistor, a third transistor as a drive transistor, a fourth transistor as a data writing transistor, and a ninth transistor as an isolation transistor, wherein the second transistor is an oxide transistor, and the third transistor, the fourth transistor, and the ninth transistor are poly silicon transistors;
• a gate electrode of the third transistor is connected to a second electrode of the ninth transistor, a first electrode of the third transistor is connected to a second electrode of the fourth transistor, a second electrode of the third transistor is connected to a second electrode of the second transistor, a first electrode of the second transistor is connected to a first electrode of the ninth transistor, and a first electrode of the fourth transistor is connected to a data signal line;
• the display substrate is configured to display respective display content, the display content comprises a plurality of display frames, at least one display frame comprises a refresh frame and at least one hold frame, the refresh frame at least comprises a data writing stage;
• the second transistor and the ninth transistor are configured such that, in the data writing stage, a moment at which the ninth transistor is turned off is earlier than a moment at which the second transistor is turned off.