function check(form) {

	for (i=0; i<form.elements.length-1; i++ ) { /* -1=ignora ultimo */

  if ( form.elements[i].value=="" ) {

		alert(	"\nfill the field #"+(i+1)+

			" ("+form.elements[i].name+")");

		document.form.elements[i].focus();

		return false;

	  }

	}

	

	//valida especialidad	   

	function Radio(radio) 

	{ 

  	for(i = 0;i < radio.length;i++) 

	  { 

  	  if(radio[i].checked) 

    	{ 

      return true; 

   	 } 

  	} 

  	return false; 

	} 

	 if(!Radio(document.form.opc)) 

	  { 

    alert("Check specialty .") 

    return false; 

  }

	

	//validar telefono

	/*var er_telefono = /^([0-9\+\-])+$/

	//comprueba campos de telefonos (permite campos vacios y guiones)

   if( !er_telefono.test(form.Phone.value) ) {

      alert('invalid Phone.')

	  document.form.Phone.focus();

      return false

   }*/

	

	//validar codigo postal

	var er_cp = /^([0-9\+\-])+$/

	//comprueba campos de telefonos (permite campos vacios y guiones)

   if( !er_cp.test(form.Postal_code.value) ) {

      alert('Invalid Postal Code.')

	  document.form.Postal_code.focus();

      return false

   }

   

   //validar codigo fax

	/*var er_fax = /^([0-9\+\-])+$/

	

   if( !er_cp.test(form.Fax.value) ) {

      alert('Invalid Fax.')

	  document.form.Fax.focus();

      return false

   }*/

   

 	

	// Valida e-mail

	var email=form.Email.value;

	if ( /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(email)==false ) {

		window.alert("ˇ E r r o r !\n\n  Invalid mail: "+email);

		document.form.Email.focus();

		return false;

		

	}

	

	

	if (!document.form.patologia.checked && !document.form.teoricas.checked && !document.form.diseccion.checked && !document.form.anestesia.checked){

		alert ("Check interesting course");

		document.form.patologia.focus();

		return false;

	}

		



	

		

	var version=parseInt(navigator.appVersion.substr(0,1));

	if ( window.RegExp==null || version<4 ) {

		window.alert("Tu navegador no soporta JavaScript1.2\n"+

			"Utiliza IE/Netscape 4.0 o más reciente");

		return false;

	}

	 

	

	window.alert("OK!!\n\n!!");

	//return 1;

   }