\documentclass[letterpaper,11pt]{article}
% Use \usepackage[warnundef]{jabbrv} to show undefined abbreviation warnings
\usepackage{jabbrv}
% Old-school compressed citations:
%\usepackage{cite}
% New way for compressed citations (hyperref compatible):
\usepackage[numbers,sort&compress]{natbib}
% Defining a custom abbreviation:
\DefineJournalAbbreviation{Test}{Tes} % <-- Note that there is no period!
% Define custom commands used in the BibTeX file:
\newcommand{\tjri}{Test Journal of Reference Information}
\begin{document}
Test
\cite{%
ref:TestNoPeriod,ref:TestDiacritic,ref:TestException,ref:Test,ref:TestJabbrv,ref:TestPeriod,%
ref:TestPeriodTwoWords,ref:TestPeriodRefInf,ref:TestPeriodInf,ref:TestMyAbbrvOneWord,%
ref:TestMyAbbrvTwoWords,ref:TestPeriodInfPeriod,ref:CmdTest,ref:AbbrvTest,%
ref:TestNBSP,%
ref:TestSlash,%
ref:TestSlashSpace,%
ref:TestUnderscore,%
ref:SymbolTest%
}.
\JournalTitle{Briefings in Functional Genomics}.
\bibliographystyle{jabbrv_unsrt} % <-- Note that a custom jabbrv-compatible style is used!
%\bibliographystyle{jabbrv_vancouver} % Needs the option noperiod
\bibliography{example}
\end{document}