With the help of RRUZ's answer above I finally came up with this code for Borland Delphi:

const
  THREAD_TERMINATE                 = $0001;
  THREAD_SUSPEND_RESUME            = $0002;
  THREAD_GET_CONTEXT               = $0008;
  THREAD_SET_CONTEXT               = $0010;
  THREAD_SET_INFORMATION           = $0020;
  THREAD_QUERY_INFORMATION         = $0040;
  THREAD_SET_THREAD_TOKEN          = $0080;
  THREAD_IMPERSONATE               = $0100;
  THREAD_DIRECT_IMPERSONATION      = $0200;
  THREAD_SET_LIMITED_INFORMATION   = $0400;
  THREAD_QUERY_LIMITED_INFORMATION = $0800;
  THREAD_ALL_ACCESS                = STANDARD_RIGHTS_REQUIRED or SYNCHRONIZE or $03FF;

function OpenThread(dwDesiredAccess: DWord;
                    bInheritHandle: Bool;
                    dwThreadId: DWord): DWord; stdcall; external 'kernel32.dll';


procedure TForm1.Button1Click(Sender: TObject);
var iii:integer;
    handle:thandle;
    creationtime,exittime,kerneltime,usertime:filetime;
begin
  Handle:=OpenThread(THREAD_SET_INFORMATION or THREAD_QUERY_INFORMATION, False, windows.GetCurrentThreadId);
  if handle<>0 then
  begin
    getthreadtimes(Handle,creationtime,exittime,kerneltime,usertime);
    label1.caption:='Total time for Thread #'+inttostr(windows.GetCurrentThreadId)+': '+inttostr( (int64(kerneltime)+int64(usertime)) div 1000 )+' msec';
    CloseHandle(Handle);
  end;
end;