  We have measured the transport properties of a series of underdoped YBa2Cu3O7
nanowires fabricated with widths of 100-250 nm. We observe large telegraph-like
fluctuations in the resistance between the pseudogap temperature T* and the
superconducting transition temperature Tc, consistent with the formation and
dynamics of a domain structure such as that created by charge stripes. We also
find anomalous hysteretic steps in the current-voltage characteristics well
below Tc.
