What are these ports for?

[herbert langhans <w3%langhans.com.pl@localhost>]

Hi List
- a question about open ports. Scanning one of the comps here (nmap)
  tells me among others:
...
135/tcp filtered msrpc
139/tcp filtered netbios-ssn
445/tcp filtered microsoft-ds
...

Where do they come from? I already switched most daemons off, still they
are there. Any MS-programs or services need them??

Actually they are not 'open', they are 'filtered'. Hmmm...

Thanks,
herb langhans