Heteroaryl groups are optionally substituted independently with one or more substituents described herein propecia vs finasteride The precise diagnosis of Bartonella species in human blood and lesions has provided us with the names of infectious organism associated with a number of diseases, but this new knowledge has not shed much light on why Bartonella can circulate in the blood without causing any reaction, for indefinite periods of time, or why any given Bartonella species may be associated with any of several diverse clinical manifestations