Pharmaceutical site- review please

[pharma]

hi our pharmaceutical articles website URL:http://www.pharmainfo.net

We completed 8 months back. Got some back links. Basically we are providing all pharmaceutical articles available online with few words of description of the article and link to that perticular URL.We used postnuke CMS.

Recently google started dropping all my pages( 25,000 to 2000). I am not sure what did wrong i did. Could you please throw some light.

Is it key words fault ?
Page tiltle fault ?
URL's fault ?
any thing else...?

please advise.

_ pharma

[seo guy]

where did you get the 25000 pages of content? Perhaps it was a duplication issue?

[pharma]

Thanks for the reply. Could you please eloborate your thoughts on duplicate content.....

20,000 pages include print.html, sendarticle.html, Dynamic URL and Static URL for the same article etc

I have around 3,000 articles ...please advise