Antibiotic synergy with enterococcal endocarditis experienced a high relapse rate when penicillin G alone was used for treatment and a demonstrably lower relapse rate when streptomycin was combined with penicillin G to combat the infection. Since that time the research community has conducted numerous studies regarding the effects and possibilities of antibiotic combinations. Today, combination therapy is recognized as providing a broad spectrum of antibiotic coverage, effectively fighting polymicrobial infections, minimizing selection for antibiotic resistant strains, lowering dose toxicity where applicable, and in some cases providing synergistic activity. Antibiotic synergy is desirable in a clinic sense for several reasons. At the patient
Discovered attack referred to as a "discovered attack" (or "check") "with capture". When the moving piece moves to a square from which it threatens to inflict checkmate on the next move, the tactic is called a "discovered attack with mate threat". A "discovered checkmate" itself is also possible. In exceptional circumstances, it is possible for the moved piece to give a "double discovered check" (though this name is not actually used). The only way for this to happen in orthodox chess is by way of an "en passant" capture. In the position shown at right, Black has just played 1...g7–g5. White replies