1. Preface

   • Anna Borsodi

   EditorialNotes Open access 30 December 2003 Pages: 137 - 138

2. The Aim of My Life is to Study the Nature

   • Maria Wollemann

   Announcement Open access 30 December 2003 Pages: 139 - 146

3. Kappa-Receptor Selective Binding of Opioid Ligands with a Heterocyclic Bicyclo[3.3.1]nonan-9-One Structure

   • S. Benyhe
   • Á. Márki
   • Anna Borsodi

   OriginalPaper Open access 30 December 2003 Pages: 147 - 155

4. Upregulation of Mu Opioid Receptors by Voluntary Morphine Administration in Drinking Water

   • Gabriella Fábián
   • B. Tombor
   • Mária Szűcs

   OriginalPaper Open access 30 December 2003 Pages: 157 - 166

5. Restraint Stress and Anti-Tumor Immune Response in Mice

   • V. P. Osevitz
   • C. Vizler
   • Anna Borsodi

   OriginalPaper Open access 30 December 2003 Pages: 167 - 176

6. Effects of Structural Modifications of N-CPM-Normorphine Derivatives on Agonist and Antagonist Activities in Isolated Organs

   • P. Riba
   • Z. Tóth
   • S. Fürst

   OriginalPaper Open access 30 December 2003 Pages: 177 - 181

7. Potencies and Selectivities of Inhibitors of Acetylcholinesterase and Its Molecular Forms in Normal and Alzheimer’s Disease Brain

   • Z. Rakonczay

   OriginalPaper Open access 30 December 2003 Pages: 183 - 189

8. The P2Y Nucleotide Receptors in the Human Genome

   • J. Simon
   • E. A. Barnard

   OriginalPaper Open access 30 December 2003 Pages: 191 - 201

9. The Molecular Mechanisms of Cellular Tolerance to δ-Opioid Agonists

   • Eva V. Varga

   ReviewPaper Open access 30 December 2003 Pages: 203 - 218