Note 2 - Stockholders' Equity, Stock Options and Warrants (Tables)

6 Months Ended

Jun. 30, 2017

Notes Tables

Share-based Compensation, Activity [Table Text Block]

	Stock Options					Warrants
	Number of Shares			Average Exercise Price		Number of Shares			Average Exercise Price
Outstanding at December 31, 2015		31,350		$	133.23		323,099		$	128.40
Issued		157,982			3.14		1,487,881			0.71
Expired		(22,377	)		122.13		-			-
Exercised		(1,312	)		65.75		(939,879	)		-
Outstanding at December 31, 2016		165,643		$	11.22		871,101		$	52.22
Issued		2,442,168			1.47		385,000			2.25
Expired		(12,730	)		10.39		(304	)		281.95
Exercised		-			-		-			-
Outstanding at June 30, 2017		2,595,081		$	2.05		1,255,797		$	36.84

Schedule of Share-based Compensation Shares Authorized Under Stock Option and Warrant Plans by Exercise Price Range [Table Text Block]

Range of Prices		Shares		Weighted Remaining Life
Options
$	1.47		2,427,882		9.98
$	2.10		14,286		9.76
$	2.25		293		9.16
$	2.42		24,768		9.14
$	2.80		57,145		9.51
$	3.75		44,000		9.01
$	4.125		3,636		9.26
$	4.1975		7,147		9.22
$	4.25		3,529		8.76
$	5.125		3,902		9.19
$	65.75		190		8.31
$	73.50		1,157		8.51
$	77.50		2,323		8.01
$	80.25		187		8.26
$	86.25		232		7.76
$	131.25		81		5.19
$	148.125		928		5.72
$	150.00		1,760		5.13
$	162.50		123		7.51
$	206.25		121		7.26
$	248.4375		121		6.04
$	262.50		130		6.04
$	281.25		529		5.55
$	318.75		3		5.86
$	346.875		72		6.76
$	431.25		306		6.69
$	506.25		188		6.51
$	596.25		42		6.25
			2,595,081
Warrants
$	2.25		385,000		4.57
$	4.46		756,999		4.42
$	93.75		2,255		0.70
$	123.75		94,084		3.17
$	150.00		4,114		0.70
$	225.00		107		0.57
$	243.75		2,529		2.10
$	281.25		5,593		0.48
$	309.375		2,850		2.11
$	309.50		222		2.36
$	337.50		178		0.97
$	371.25		944		0.91
$	506.25		59		1.63
$	609.375		862		1.60
			1,255,797

Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block]

Stock Options:
Year	Shares		Price
2011		173			$ 281.25
2012		1,841		131.25		–	150.00
2013		1,553		148.13		–	596.25
2014		835		162.50		–	431.25
2015		4,088		65.75		–	86.25
2016		144,423		2.25		–	5.13
2017		2,442,168		1.47		–	2.10
Total		2,595,081	$	1.47		–	596.25

Warrants:
Year	Shares		Price
2012		2,488			$ 281.25
2013		10,703		93.75		–	371.25
2014		6,455		243.75		–	609.38
2015		94,152		0.00		–	243.75
2016		756,999				4.46
2017		385,000				2.25
Total		1,255,797	$	0.00		–	609.38