Open Database Connectivity, commonly known as
, defines a
database-independent API. The
ODBC Driver Manager
supports the API and manages one
or more plug-in drivers for talking to different types of databases.
The architecture is shown in Figure 7.1.
Figure7-1.The ODBC architecture
Doesnt this all sound rather familiar? The ODBC driver manager
and drivers are doing just what the DBI and its drivers are doing:
defining and implementing a database-independent,
This leads us to a whole bunch of questions: Whats the
difference? Why not just use ODBC and not the DBI? Can the DBI and
ODBC work together? What advantages does one have over the other?
Before we try to answer those questions, lets get some
perspective by looking into the history and goals of ODBC and the
DBI, and take a look at the Win32::ODBC module,
which implements a direct interface to ODBC for Perl.
In the early 1990s, a consortium of vendors formed the
Group to support SQL interoperability across disparate systems. In
October 1992 and October 1993, a major part of that work was
published as a draft standard entitled
"Call Level Interface, or CLI,
which is another name for an Application Programing
Interface, or API. However, the SQL Access Group CLI standard never
really took off. At least, not in that form.
Botulinum toxin (BoTN) is effective and often the primary and adjunctive therapy for a variety of diverse motor disorders manifested by dystonic and non-dystonic excessive muscle contraction and spasticity (Table 1), with the list continuing to grow. This chapter addresses the neuropharmacological and clinical aspects of BoTN.
The origin, structure, pharmacologic activity, and uses of BoTN have been extensively reviewed (1, 2). In essence, when botulinum neurotoxin is isolated from bacterial cultures, it is normally associated with non-toxic macromolecules such as proteins and nucleic acids. Administered parenterally for therapeutic use, the non-toxic proteins do not enhance the activity of the neurotoxin and may even interfere slightly. However, orally administered, they enhance its activity by protecting the neurotoxin from proteolytic enzymes in the gut.