This is easy in Notepad++ with a regular expression, but it is also easy to get it wrong and to wrongly delete or change things. So first, make sure you have a backup of the file, not just the backups that Notepad++ will keep, but make your own backup copy. Then it is easy to revert if you mess things up.
Also note that “wildcards” and “regular expressions” are different. Notepad++ supports regular expressions, it does not do wildcards.
All the numbers to be altered in the example text have 3 or 4 digits and are preceded by a space and then have the f or t. Then there is another space or a comma or the end of line. These strings can be removed by replacing " \d{3,4}[ft](,| |$)" with a single space. That leaves the text as:
granuloma 553 irritant/toxic causes
eruption 551Ð552, idiopathic facial
pathogenesis 545,
833 adhesion molecules adhesion proteins
The question is not clear whether the remaining numbers above, i.e. those without a t or f, should be removed. Assuming they are to be removed then the above regular expression could be altered to be “(^| )\d{3,4}[ft]?(,| |$)”. Using it gives the result
granuloma irritant/toxic causes
eruption 551Ð552, idiopathic facial
pathogenesis
adhesion molecules adhesion proteins
This leaves 3 issues that I can see.
The “551Ð552” . There should not be many numbers left. They can be searched for and removed manually.
Leading and trailing spaces on lines. Use menu =>
Edit =>
Blank operations =>
Trim leading and trailing spaces.
Embedded double spaces (came from the two replacements at “1684f, 1685t”. Just do a replace-all of two spaces with one space and repeat until no more changes found.
Note that using simple regular expressions such as “\d{3,4}[ft]” is unwise for this task. It would change, for example, “ulna 123fibia radius 45678tibia pelvis” to be ulna ibia radius 4ibia pelvis". Thus removing wanted letters and leaving some digits in place.