Note 3 - Summary of Significant Accounting Policies (Details Textual)	3 Months Ended
	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Net Income (Loss) Attributable to Parent, Total	$ (1,138,000)	$ (565,000)
Cash and Cash Equivalents, at Carrying Value, Ending Balance	1,483,000	7,503,000	$ 3,742,000	$ 2,952,000
Net Cash Provided by (Used in) Operating Activities, Total	(2,270,000)	(3,179,000)
Contract with Customer, Performance Obligation Satisfied in Previous Period	0	0
Advertising Expense		389,000
Research and Development Expense, Total	$ 201,000	218,000
Lessee, Operating Lease, Discount Rate	6.00%
Operating Lease, Right-of-Use Asset	$ 20,000
Operating Lease, Liability, Total	10,000
Operating Lease, Cost	90,000	$ 100,000
Other Current Assets [Member]
Operating Lease, Right-of-Use Asset	20,000
Other Current Liabilities [Member]
Operating Lease, Liability, Total	$ 10,000
Minimum [Member]
Lessee, Operating Lease, Term of Contract	2 years
Maximum [Member]
Lessee, Operating Lease, Term of Contract	3 years
CHINA
Number of Lease Offices	2
Beijing [Member]
Number of Lease Offices	1
Hubei [Member]
Number of Lease Offices	1