[R] Significance in Count data

[João Fadista]

Dear all,
 
I have some count data and I would like to know how can I assess which are the items in my dataset that have a count significantly smaller or bigger than I would expect (each item with the same number of counts, i.e. from a uniform distribution).
 
Example file: 
 
 Item  Count
A0001    48
A0002    39
A0003    28
A0004    16
A0005    13
A0006    2   
...            ...
A9999    15
 
 
Best regards,
João Fadista