var imageParameters = new esri.layers.ImageParameters();
    imageParameters.layerIds = [1];
    imageParameters.layerOption = esri.layers.ImageParameters.LAYER_OPTION_SHOW;
    polylineMLayer = new esri.layers.ArcGISDynamicMapServiceLayer("http://www.address_of_your_REST_service/MapServer", {
        "imageParameters": imageParameters,
        id: "polylineMLayer"
    });
    map.addLayer(polylineMLayer);