  A large positive magnetoresistivity (up to tens of percents) is observed in
both underdoped and overdoped superconducting La2-xSrxCuO4 epitaxial thin films
at temperatures far above the superconducting critical temperature Tc. For the
underdoped samples, this magnetoresistance far above Tc cannot be described by
the Kohler rule and we believe it is to be attributed to the influence of
superconducting fluctuations. In the underdoped regime, the large
magnetoresistance is only present when at low temperatures superconductivity
occurs. The strong magnetoresistivity, which persists even at temperatures far
above Tc, can be related to the pairs forming eventually the superconducting
state below Tc. Our observations support the idea of a close relation between
the pseudogap and the superconducting gap and provide new indications for the
presence of pairs above Tc.
