var top_button_alexa=new Image();
var top_button_microarray=new Image();
var top_button_proteomics=new Image();
var top_button_cell_bio=new Image();
var top_button_genomics=new Image();

var top_button_alexa_o=new Image();
var top_button_microarray_o=new Image();
var top_button_proteomics_o=new Image();
var top_button_cell_bio_o=new Image();
var top_button_genomics_o=new Image();

top_button_alexa.src="./img/top_button_alexa.gif";
top_button_microarray.src="./img/top_button_microarray.gif";
top_button_proteomics.src="./img/top_button_proteomics.gif";
top_button_cell_bio.src="./img/top_button_cell_bio.gif";
top_button_genomics.src="./img/top_button_genomics.gif";

top_button_alexa_o.src="./img/top_button_alexa_o.gif";
top_button_microarray_o.src="./img/top_button_microarray_o.gif";
top_button_proteomics_o.src="./img/top_button_proteomics_o.gif";
top_button_cell_bio_o.src="./img/top_button_cell_bio_o.gif";
top_button_genomics_o.src="./img/top_button_genomics_o.gif";