function newImage(arg) {
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}

function changeImages() {
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        dermatophyten_over = newImage("../intro_images/dermatophyten-over.gif");
        pankreas_over = newImage("../intro_images/pankreas-over.gif");
        entzuendungsmarker_over = newImage("../intro_images/entzuendungsmarker-over.gif");
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        blutungen_over = newImage("../intro_images/blutungen-over.gif");
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        parasitologie_over = newImage("../intro_images/parasitologie-over.gif");
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}