To solve this expression, we will follow the order of operations (PEMDAS):

First, we will calculate within the parentheses:
(49.001 - 49) = 0.001

Next, we will perform division:
0.395 / 0.001 = 395

Now, we will take care of the multiplication:
-0.05 * 10.1 = -0.505

Finally, we will add and subtract:
0.0023 - 0.505 + 395 = 394.4973

Therefore, the result of the expression 0.0023 - 0.05 10.1 + 0.395 / (49.001 - 49) 0.00 is 394.4973.