how to make all xsl:value-of outputs bold

hi, i've been googling a lot and am relatively still an xsl newbie. i
was wondering how to make all the xsl:value-of outputs in my xslt to
output in bold, with only using like one line at the top of the xslt
file. is that possible? as opposed to wrapping all of them in span
tags...

i have hard coded text that i don't want to be bold, but all the
imported text by way of xsl:value-of tags i want to be bold, for
example:
==========code============
<fo:block>Via</fo:block>
<fo:block>
<xsl:value-of select="Via/Name" />
</fo:block>
==========/code============