<?php
    $str = "!@#$%^&*()_+AdsfdfОкайسۺۻܔݜ";

    $rx = '/[^0-9A-zА-яёЁ\!\@\#\$\%\^\&\*\(\)\-\_\+\=\.\?\|\/\,\"\']/u';

    $str = preg_replace($rx,'',$str);

    var_dump($str);
?>