This is the last option on the New Analysis screen of iCite:
Paste a list of PMIDs separated with whitespace, commas, or semicolons. For example, copy a spreadsheet column and paste it here.
A maximum of 50,000 PMIDs may be queried at a time. Only the first 50,000 will be submitted to iCite.
Finally, click "Process" to proceed to the next page.
If more IDs are uploaded, you will receive an error message, although results will still populate: