Contents 
269 Cancer and Genetic Modification of Biologic Control 
Philip Leder, M.D. 
271 Molecular Genetic Investigation and Therapy for Inborn Errors 
of Metabolism 
Fred D. Ledley, M.D. 
273 Molecular Biology of Hormone and Drug Receptors in Health 
and Disease 
Robert J. Lefkowitz, M.D. 
277 Genetic Control of Pattern Formation and Germline Determination 
in Drosophila 
Ruth Lehmann, Ph.D. 
281 Regulation of Gene Expression During Cell Differentiation 
and Activation 
Jeffrey M. Leiden, M.D., Ph.D. 
283 Preliminary Events in Olfaction and a Tissue-Specific snRNP Protein 
Michael R. Lerner, M.D., Ph.D. 
285 Structural Determinants of a-Globin Gene Expression 
Stephen A. Liebhaber, M.D. 
287 The Heat-Shock Response 
Susan L. Lindquist, Ph.D. 
289 T Cell Surface Glycoproteins in Development and Viral Infections 
Dan R. Littman, M.D., Ph.D. 
291 Antigen-Specific T Cell Receptors 
Dennis Y.-D. Loh, M.D. 
293 Molecular Genetics of Mammalian Glycosyltransferases 
John B. Lowe, M.D. 
295 Mechanisms of Embryonic Induction in Vertebrates 
Richard L. Maas, M.D., Ph.D. 
297 Cell Cycle Control 
James L. Mailer, Ph.D. 
299 The Role of T Cells in Health and Sickness 
Philippa Marrack, Ph.D. 
301 Control of Cell Growth and Phenotype by Transforming Growth Factors 
Joan Massague, Ph.D. 
303 Structural Basis of Interactions Within and Between Macromolecules 
Brian W. Matthews, Ph.D., D.Sc. 
307 Transcription Factor Interactions 
Steven Lanier McKnight, Ph.D. 
