\newsavebox{\abstractbox}
\def\abstract{\global\setbox\abstractbox=\hbox\bgroup
	\begin{minipage}{\textwidth}
	\textbf{Abstract\quad}}
\def\endabstract{\end{minipage}\egroup}

\newsavebox{\keywordbox}
\def\keyword{\global\setbox\keywordbox=\hbox\bgroup
	\begin{minipage}{\textwidth}
	\textbf{Key words\quad}}
\def\endkeyword{\end{minipage}\egroup}


\def\@maketitle{%
  \newpage
  \null
  \vskip 2em%
  \begin{center}%
  \let \footnote \thanks
    {\LARGE \@title \par}%
    \vskip 1.5em%
    {\large
      \lineskip .5em%
      \begin{tabular}[t]{c}%
        \@author
      \end{tabular}\par}%
    \vskip 1em%
    {\normalsize \@date}%
    \vskip 1em%
    {\normalsize \usebox{\abstractbox}}%
    \vskip 1em%
    {\normalsize \usebox{\keywordbox}}%
  \end{center}%
  \par
  \vskip 1.5em}