  This paper describes the first 63-Cu NMR study of an electron-doped
infinitely-layered high Tc superconductor Sr$_0.9$La$_0.1$CuO$_2$ (Tc=42K). The
spin dynamics in the normal state above Tc exhibits qualitatively the same
behavior as some hole-doped materials with significantly enhanced spin
fluctuations. Below Tc, we observed no signature of a Hebel-Slichter coherence
peak, suggesting an unconventional nature of the symmetry of the
superconducting order parameter.
