This journal provides immediate access to some articles. Volume 68(8); August 1971 Specific Heterologous Enhancement of Immune Responses PMCID: PMC389266 The Dynamics of Life, V. Applying the Steady-State Theory of Mutations to Human Cancer PMCID: PMC389267 Lipopolysaccharide and Aldoheptose Biosynthesis in Transketolase Mutants of Salmonella typhimurium PMCID: PMC389268 Entropic Contributions to Rate Accelerations in Enzymic and Intramolecular Reactions and the Chelate Effect PMCID: PMC389269 The Spectrum of Seminormal Operators PMCID: PMC389270 Systems of Conservation Equations with a Convex Extension PMCID: PMC389271 Stimulation of the Proliferation of Chicken Fibroblasts by Folic Acid or a Serum Factor(s) in a Plasma-Containing Medium PMCID: PMC389272 Neurohypophyseal Hormone-Responsive Adenylate Cyclase from Mammalian Kidney PMCID: PMC389273 The Prematurely Evoked Synthesis of Liver Tryptophan Oxygenase PMCID: PMC389274 On the Control of the Induction of β-Galactosidase in Synchronous Cultures of Escherichia coli PMCID: PMC389275 Independent Folding of the Variable and Constant Halves of a Lambda Immunoglobulin Light Chain PMCID: PMC389276 On the Theory of Ion Transport Across the Nerve Membrane, II. Potassium Ion Kinetics and Cooperativity (with x = 4) PMCID: PMC389277 Opsonic Defect in Patients with Cystic Fibrosis of the Pancreas PMCID: PMC389278 Alternative Derivations of the Statistical Mechanical Distribution Laws PMCID: PMC389279 Gene Activation in WI-38 Fibroblasts Stimulated to Proliferate: Requirement for Protein Synthesis PMCID: PMC389280 Rapid Change in Water Flux Induced by Auxins PMCID: PMC389281 X-Irradiation Enhancement of Transformation by Benzo(a)Pyrene in Hamster Embryo Cells PMCID: PMC389282 Effect of Leukocyte Transfusion in a Child with Type II Mucopolysaccharidosis PMCID: PMC389283 Stereospecific and Nonspecific Interactions of the Morphine Congener Levorphanol in Subcellular Fractions of Mouse Brain PMCID: PMC389284 Suppressive Effect of Immunization with Mouse Fetal Antigens on Growth of Cells Infected with Rauscher Leukemia Virus and on Plasma-Cell Tumors PMCID: PMC389285 N-Acetyl-D-Galactosaminyltransferase in Human Serum and Erythrocyte Membranes PMCID: PMC389286 Symmetrical In Vivo Transcription of Mitochondrial DNA in HeLa Cells PMCID: PMC389287 Are Cytoplasmic Microtubules Heteropolymers? PMCID: PMC389288 Conformational Transition in Oligopeptides: An NMR Spectroscopic Study PMCID: PMC389289 A Fraction of the Ventricular Myocardium That Has the Specificity of the Cardiac Beta-Adrenergic Receptor PMCID: PMC389290 Isolation and Properties of RNA Replicases Induced by SP and FI Phages PMCID: PMC389291 Pressure-Induced Dissociation of Sedimenting Ribosomes: Effect on Sedimentation Patterns PMCID: PMC389292 Transcriptional Organization of the Ribosomal RNA Cistrons in Escherichia Coli PMCID: PMC389293 Translocation of Messenger RNA and “Accommodation” of fMet-tRNA PMCID: PMC389294 Inhibition by Siomycin and Thiostrepton of Both Aminoacyl-tRNA and Factor G Binding to Ribosomes PMCID: PMC389295 Photo-Affinity Labels for Adenosine 3′:5′-Cyclic Monophosphate PMCID: PMC389296 Interaction of Eukaryote Initiator Methionyl-tRNA with the Eukaryote Equivalent of Bacterial Elongation Factor T and Guanosine Triphosphate PMCID: PMC389297 Initial Dipeptide Formation in Hemoglobin Biosynthesis PMCID: PMC389298 Proteins from Plant Cell Walls Inhibit Polygalacturonases Secreted by Plant Pathogens PMCID: PMC389299 Photochromic Activators of the Acetylcholine Receptor PMCID: PMC389300 Stimulation of RNA Transcription from Pea and Corn DNA by Protein Retained on Sepharose Coupled to 2,4-Dichlorophenoxyacetic Acid PMCID: PMC389301 Mechanism of Initiation of Repression of In Vitro Transcription of the Lac Operon of Escherichia coli PMCID: PMC389302 Insulin Receptors in the Liver: Specific Binding of [125I]Insulin to the Plasma Membrane and Its Relation to Insulin Bioactivity PMCID: PMC389303 Structure of the Poly(G) Polymerase Component of the Bacteriophage f2 Replicase PMCID: PMC389304 Cytoplasmic DNA synthesis Induced by RNA Tumor Viruses PMCID: PMC389305 DNA Uptake during Genetic Transformation and the Growing Zone of the Cell Envelope PMCID: PMC389306 Structure of Concanavalin A at 4 Å Resolution PMCID: PMC389307 Biochemical Differentiation in Reaggregating Brain Cell Culture PMCID: PMC389308 Divergence between Immunosuppression and Immunocompetence during Virus-Induced Leukemogenesis PMCID: PMC389309 Modification of a Specific Ribosomal Protein Catalyzed by Leucyl, Phenylalanyl-tRNA:Protein Transferase PMCID: PMC389310 Histrionicotoxins: Roentgen-Ray Analysis of the Novel Allenic and Acetylenic Spiroalkaloids Isolated from a Colombian Frog, Dendrobates histrionicus PMCID: PMC389311 Evidence for and Localization of Vegetative Viral DNA Replication by Autoradiographic Detection of RNA·DNA Hybrids in Sections of Tumors Induced by Shope Papilloma Virus PMCID: PMC389312 Isolation of a 5S RNA-Protein Complex from Mammalian Ribosomes PMCID: PMC389313 A Transition to a Compact Form of DNA in Polymer Solutions PMCID: PMC389314 Isolation of the gal Repressor PMCID: PMC389315 The “Up-Down” Problem For Operator Algebras PMCID: PMC389316 Stimulation of DNA-Dependent RNA Synthesis by a Protein Associated with Ribosomes PMCID: PMC389317 A Radioimmunoassay for Human Prolactin PMCID: PMC389318 The Gramicidin A Transmembrane Channel: Characteristics of Head-to-Head Dimerized π(L,D) Helices PMCID: PMC389319 Mutational and Physiological Enhancement of Photosynthetic Energy Conversion in Rhodopseudomonas capsulata PMCID: PMC389321 A Tribute to the Life and Work of Hugh L. Dryden PMCID: PMC389322 Symposium on Energy for the Future—Problems and Prospects PMCID: PMC389323 Initiatives for the Future of Energy PMCID: PMC389324 Electric Power from Nuclear Fission PMCID: PMC389325 Fusion Power PMCID: PMC389326 Power Generation and the Environment PMCID: PMC389327 Members of the National Academy of Sciences. PMCID: PMC389328 Correction Molecular characteristics of some carcinogenic hydrocarbons PMCID: PMC389320 Corrects: Molecular Characteristics of Some Carcinogenic Hydrocarbons. Proc Natl Acad Sci U S A. 1971 June; 68(6): 1251–1253. Journal Matter Original table of contents page Administrative content — journal masthead, notices, indexes, etc. | ||