Studies on a model immunological system.

1257 Studies on a Model Immunological System. J. H. Cronenberger and A. P. Kimball. 1261 Electron Microscopic Study of Spontaneous Mammary Carcinomas in Cats and Dogs: Virus-like Particles in Cat Mammary Car cinomas. Dorothy G. Feldman and Ludwik Gross. 1268 A Comparison of in Vivo and in Vitro Uptake of Estradiol by Human Breast Tumors and the Relationship to Steroid Excretion. Frances James, V. H. T. James, A . E. Carter, and W. T. Irvine. 1273 Carbohydrate Metabolism in Subjects with Cancer. Christine Waterhouse and Johannes H. Kemperman. 1279 The Cell Proliferation Kinetics of Four Experi mental Tumors after Acute X-irradiation. Juliana Denekamp and R. H. Thomlinson. 1285 Serological Studies of Tumor Antigens in Chemicaland Virus-induced Thymic Lym phomas. Ruth G. Doell and Bonnie J. Mathieson. 1290 Hyperbasophilic Foci as Sites of Neoplastic Transformation in Hepatic Parenchyma. R. Daoust and R. Calamai. 1297 Studies on DNA Repair in Human Lympho cytes Treated with Proximate Carcinogens and Alkylating Agents. Michael W. Lieberman, Richard N. Baney, Robert E. Lee, Stewart Sell, and Emmanuel Farber. 1307 Deoxyribonucleoside Incorporation and the Role of Hydroxyurea in a Model Lymphocyte System for Studying DNA Repair in Carcino genesis. Michael W. Lieberman, Stewart Sell, and Emmanuel Farber. 1313 Brief Communication: Adenosine 3' ,5'-Cyclic Monophosphate and Contact Inhibition. Margaret L. Heidrick and Wayne L. Ryan. 1316 Obituary : George Otto Gey. John H. Hanks and Frederick B. Bang. 1317 Special Announcement : Annual Meeting of the American Association for Cancer Re search, Inc. 1317 Announcement from the Editor. 1318 Announcements. 1318 Erratum. ,4@T