The resistive properties of layered HTSC BiSrCaCuO in the mixed state are compared with those of thin films of conventional superconductors with weak disorders (amorphous Nb_{1-x}0_{x} films) and with strong disorders (Nb_{1-x}O_{x} films with small grain structure). The excess conductivity is considered as a function of superconducting electron density and phase coherence length. It is shown that the transition to the Abrikosov state differs from the ideal case both in BiSrCaCuO and Nb_{1-x}O_{x} films, i.e. the appearance of long-range phase coherence is continuous transition in both cases. The quantitative difference between thin films with weak and strong disorders is greater than the one between layered HTSC and conventional superconductors, showing that the dimensionality of the system, rather than the critical temperature, is the key factor ruling fluctuation effects
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