### Clue: Note attempt to annul endless external organisations such as the NHS (7)
### Answer: QUANGOS 
 ### Explanation: Definition: organisations such as the NHS
 [ N(abbrev. for "note") + GO(an attempt/a try at) ] **contained in**(… external) "squash"(to annul/to put an end to) **minus ****its 1st and last letters**(endless).
I thought the wordplay's construction a bit clumsy.