Vessels around Portugal not good sign (11)

I believe the answer is:

capillaries

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'vessels' is the definition.
(capillary is a kind of vessel)

'portugal not good sign' is the wordplay.
'portugal' becomes 'cap' (I can't justify this - if you can you should believe this answer much more).
'not good' becomes 'ill' ('ill' is the opposite to 'good').
'sign' becomes 'aries' (star sign).
'cap'+'ill'+'aries'='CAPILLARIES'

'around' is the link.

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I've seen this clue in The Telegraph.

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