1. Thalidomide - Toxipedia

   "Before thalidomide, it was assumed that the placenta provided an effective
   barrier to exogenous substances" (Dr. Rita Loch-Caruso, University of Michigan).
   

   toxipedia.org/display/toxipedia/Thalidomide - Cached - Similar

2. Thousands Protest Roe V. Wade Decision - Topix

   "Before thalidomide, it was assumed that the placenta provided an effective
   barrier to exogenous substances". http://toxipedia.org/display/toxipedia/Thalid.
   

   www.topix.com/forum/news/abortion/.../p10898 - Cached

3. Thousands Protest Roe V. Wade Decision - Topix

   ... drug thalidomide for example: "Before thalidomide, it was assumed that the
   placenta provided an effective barrier to exogenous substances".
   

   www.topix.net/forum/city/severn-md/.../p10802 - Cached

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