I took your strings verbatim and ran my regular expression match. Code and results follow:

@strings = ("PMID: PMID: 4012367", "PMID: doi:10.1093/fampra/cmq003PMI
+D: 20215333");

for $string (@strings) {
    if ($string =~ /PMID: (\d+)/) {
    print "$1\n";
    }
}

#OUTPUT
#4012367
#20215333

[download]

I'm not exactly sure what your problem is but my code does what I believe you want to accomplish.

In reply to Re^5: Extracting web data by zek152
in thread Extracting web data by smandape1

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