If you are looking for a partner SME/research center/university to participate in any of the HEALTH FP7 projects you can register here: http://www.fitforhealth.eu/Common/ContactsLogin.asp
After you register you have the possibility to publish your profile so that others can find you, publish a partner search, or download other partner searches which might match your profile.
Also, specifically for Greece you can also register in http://www.enterprise-hellas.gr/services/Innovation/amt.dot to look up partners according to your area of expertise.
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