Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Notes receivable	$ 250,000	$ 497,276
Reserve for bad debt	787,524	787,524
Discount of note payable	$ 573,155	$ 1,032,814
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares outstanding (in shares)	30,974,761	14,091,748
Series E Convertible Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.01
Preferred stock, shares authorized (in shares)	350
Preferred stock, shares outstanding (in shares)	83.4
Preferred stock, liquidation value	$ 843,000
Series B Convertible Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares outstanding (in shares)	79,246	79,246
Series D Convertible Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000
Preferred stock, shares outstanding (in shares)	3,500,000	0
Helomics Holding [Member]
Notes receivable	$ 0	$ 452,775