<table>
<tbody id="encabezado">
<tr>
<th>Encabezado 1</th>
<th>Encabezado 2</th>
</tr>
</tbody>
<tbody id="contenido" style="height: 400px; overflow: auto">
<tr>
<td>celda1</td>
<td>Celda 2</td>
</tr>
<tr>
<td>celda1</td>
<td>Celda 2</td>
</tr>
<tr>
<td>celda1</td>
<td>Celda 2</td>
</tr>
<tr>
<td>celda1</td>
<td>Celda 2</td>
</tr>
</tbody>
</table>