the freeze-drying process comprises the following steps, preparing a liquid and filling at the temperature of 20-30 , putting a sample into a freeze dryer, quickly reducing the temperature of a plate layer to-40 , preserving heat for 1h, when the temperature of a partition plate is-10 +/-2 , preserving heat for 1h, quickly reducing the temperature of the plate layer to-40 within 1h, preserving heat for 2-4 h, transferring to a cold trap at-50 , vacuumizing to below 10Pa, firstly preserving the temperature of the plate layer at-5 for 2-4 h, then heating the plate layer to 10 within 3h, when a product is heated to 0 , starting to increase the temperature of the plate layer to 40 , and preserving heat for 4-6 h after the product is heated to 30
Then, 500 l/well of the cell-collagen mixture was dispensed in a 24-well plate, and incubated for 1 h at 37 C until gelled
2005;93(S1):S157-S161
Current research has shown that mild cognitive impairment in Parkinsons patients is associated with brain energy metabolism (23)