Reciprocity and behavioral heterogeneity govern the stability of social networks.

abstract：:Fibroblasts can condense a hydrated collagen lattice to a tissue-like structure 1/28th the area of the starting gel in 24 hr. The rate of the process can be regulated by varying the protein content of the lattice, the cell number, or the concentration of an inhibitor such as Colcemid. Fibroblasts of high population do...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Bell E,Ivarsson B,Merrill C

更新日期：1979-03-01 00:00:00

abstract：:Endothelin 1 causes a strong Ca2+ signal in C6 rat glioma cells as measured by fura-2 fluorescence. This endothelin 1-induced Ca2+ signal was not observed when the cells were persistently infected with a measles virus strain of subacute sclerosing panencephalitis (SSPE, strain Lec). Binding of 125I-labeled endothelin ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tas PW,Koschel K

更新日期：1991-08-01 00:00:00

abstract：:We used positron emission tomography (PET) to examine the role of the hippocampal formation in implicit and explicit memory. Human volunteers studied a list of familiar words, and then they either provided the first word that came to mind in response to three-letter cues (implicit memory) or tried to recall studied wo...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Schacter DL,Alpert NM,Savage CR,Rauch SL,Albert MS

更新日期：1996-01-09 00:00:00

abstract：:Transformation of murine thymocytes by radiation leukemia virus is associated with reduced expression of the class I antigens encoded in the major histocompatibility complex (MHC) and increased methylation and altered restriction enzyme patterns of MHC DNA. These changes may play a role in host susceptibility to virus...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Meruelo D,Kornreich R,Rossomando A,Pampeno C,Boral A,Silver JL,Buxbaum J,Weiss EH,Devlin JJ,Mellor AL

更新日期：1986-06-01 00:00:00

abstract：:Artificial two-dimensional biological habitats were prepared from porous polymer layers and inoculated with the fungus Penicillium roqueforti to provide a living material. Such composites of classical industrial ingredients and living microorganisms can provide a novel form of functional or smart materials with capabi...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gerber LC,Koehler FM,Grass RN,Stark WJ

更新日期：2012-01-03 00:00:00

abstract：:The mitochondrial enzyme glutaminase C (GAC) catalyzes the hydrolysis of glutamine to glutamate plus ammonia, a key step in the metabolism of glutamine by cancer cells. Recently, we discovered a class of allosteric inhibitors of GAC that inhibit cancer cell growth without affecting their normal cellular counterparts, ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Stalnecker CA,Ulrich SM,Li Y,Ramachandran S,McBrayer MK,DeBerardinis RJ,Cerione RA,Erickson JW

更新日期：2015-01-13 00:00:00

abstract：:Depolarization of neuroblastoma cells causes a 70-fold increase in the apparent dissociation constant KD for scorpion toxin enhancement of activation of the action potential Na+ ionophore by veratridine and a large increase in the rate of reversal of scorpion toxin action. Depolarization also inhibits binding of 125I-...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Catterall WA,Ray R,Morrow CS

更新日期：1976-08-01 00:00:00

abstract：:A 900-base-pair (bp) sequence from a cDNA clone of the rye endosperm-storage-protein gene Sec-1 was labeled with biotin and hybridized to Secale cereale 'Blanco' chromosomes. Hybridization was seen on the satellite part of the short arm of chromosome 1R, where the Sec-1 gene has been genetically mapped, in approximate...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gustafson JP,Butler E,McIntyre CL

更新日期：1990-03-01 00:00:00

abstract：:Certain cheU mutants of Salmonella show inverted chemotactic behavior, being repelled by attractants and attracted by repellents. Such a dramatic change in behavioral pattern would seem at first glance to require drastic and complex alterations in the sensory processing system. In fact, the behavior can be explained b...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Khan S,Macnab RM,DeFranco AL,Koshland DE Jr

更新日期：1978-09-01 00:00:00

abstract：:Cellular cholesterol metabolism is regulated primarily through the coordinate expression of two proteins, the low density lipoprotein (LDL) receptor and 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase (EC 1.1.1.34). We have used cDNA probes for the human genes encoding these proteins to determine the precise...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Lindgren V,Luskey KL,Russell DW,Francke U

更新日期：1985-12-01 00:00:00

abstract：:The nodZ gene, which is present in various soil bacteria such as Bradyrhizobium japonicum, Azorhizobium caulinodans, and Rhizobium loti, is involved in the addition of a fucosyl residue to the reducing N-acetylglucosamine residue of lipochitin oligosaccharide (LCO) signal molecules. Using an Escherichia coli strain th...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Quinto C,Wijfjes AH,Bloemberg GV,Blok-Tip L,López-Lara IM,Lugtenberg BJ,Thomas-Oates JE,Spaink HP

更新日期：1997-04-29 00:00:00

abstract：:Several overlapping chromosomal deletions spanning the albino locus in the mouse cause perinatal lethality when homozygous and a block in the transcriptional induction of various unlinked hepatocyte-specific genes. Studies of such lethal albino deletion homozygotes in perinatal stages revealed a deficiency in the tran...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Zaret KS,Milos P,Lia M,Bali D,Gluecksohn-Waelsch S

更新日期：1992-07-15 00:00:00

abstract：:Little is known about how genetic variation and epigenetic marks interact to shape differences in behavior. The foraging (for) gene regulates behavioral differences between the rover and sitter Drosophila melanogaster strains, but the molecular mechanisms through which it does so have remained elusive. We show that th...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Anreiter I,Kramer JM,Sokolowski MB

更新日期：2017-11-21 00:00:00

abstract：:As an aid to the study of bovine tuberculosis (TB), a simple model has been developed of an epidemic involving two species, cattle and badgers. Each species may infect the other. The proportion of animals affected is assumed relatively small so that the usual nonlinear aspects of epidemic theory are avoided. The model...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Cox DR,Donnelly CA,Bourne FJ,Gettinby G,McInerney JP,Morrison WI,Woodroffe R

更新日期：2005-12-06 00:00:00

abstract：:According to a current "RNA first" model for the origin of life, RNA emerged in some form on early Earth to become the first biopolymer to support Darwinism here. Threose nucleic acid (TNA) and other polyelectrolytes are also considered as the possible first Darwinian biopolymer(s). This model is being developed by re...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kim HJ,Benner SA

更新日期：2017-10-24 00:00:00

abstract：:Cancer vaccines genetically engineered to produce interleukin 2 have been investigated intensively in a series of animal models and are at the point of entering into clinical trials. In this study we demonstrate a strong correlation between the rate of interleukin 2 production and the protection efficiency of murine S...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Schmidt W,Schweighoffer T,Herbst E,Maass G,Berger M,Schilcher F,Schaffner G,Birnstiel ML

更新日期：1995-05-09 00:00:00

abstract：:Combined intracellular and microfluorometric recording techniques were used to evaluate whether the inhibition by cholinergic or adrenergic transmitters of the Ca2(+)-activated potassium current (IAHP) in hippocampal CA3 pyramidal cells was mediated by an alteration of depolarization-induced change in cytosolic free C...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Knöpfel T,Vranesic I,Gähwiler BH,Brown DA

更新日期：1990-06-01 00:00:00

abstract：:Cellular regulation by certain growth factor receptors and protooncogene products involves tyrosine kinase activity with the resultant tyrosine phosphorylation of protein substrates. In the present report we describe the distribution of phosphotyrosine-containing material detected by immunocytochemistry (ICC) in the r...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Moss AM,Unger JW,Moxley RT,Livingston JN

更新日期：1990-06-01 00:00:00

abstract：:Creatine, a nitrogenous organic acid, replenishes cytoplasmic ATP at the expense of mitochondrial ATP via the phosphocreatine shuttle. Creatine levels are maintained by diet and endogenous synthesis from arginine and glycine. Glycine amidinotransferase (GATM) catalyzes the rate-limiting step of creatine biosynthesis: ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Turer E,McAlpine W,Wang KW,Lu T,Li X,Tang M,Zhan X,Wang T,Zhan X,Bu CH,Murray AR,Beutler B

更新日期：2017-02-14 00:00:00

abstract：:Insufficient and disrupted sleep is linked with cardiovascular and metabolic dysregulation and morbidity. The current study examines the degree to which differences in sleep between black/African American (AA) and white/European American (EA) adults explain racial differences in cardiometabolic (CMB) disease risk. Tot...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Curtis DS,Fuller-Rowell TE,El-Sheikh M,Carnethon MR,Ryff CD

更新日期：2017-08-15 00:00:00

abstract：:Blocking CD28-B7 T-cell costimulation by systemic administration of CTLA4Ig, a fusion protein which binds B7 molecules on the surface of antigen-presenting cells, prevents rejection and induces tolerance in experimental acute allograft rejection models. We tested the effect of CTLA4Ig therapy on the process of chronic...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Azuma H,Chandraker A,Nadeau K,Hancock WW,Carpenter CB,Tilney NL,Sayegh MH

更新日期：1996-10-29 00:00:00

abstract：:A fundamental issue in human development concerns how the young infant's ability to recognize emotional signals is acquired through both biological programming and learning factors. This issue is extremely difficult to investigate because of the variety of sensory experiences to which humans are exposed immediately af...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Pollak SD,Kistler DJ

更新日期：2002-06-25 00:00:00

abstract：:Base excision repair (BER) removes at least 20,000 DNA lesions per human cell per day and is critical for the maintenance of genomic stability. We hypothesize that aberrant BER, resulting from mutations in BER genes, can lead to genomic instability and cancer. The first step in BER is catalyzed by DNA N-glycosylases. ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Galick HA,Kathe S,Liu M,Robey-Bond S,Kidane D,Wallace SS,Sweasy JB

更新日期：2013-08-27 00:00:00

abstract：:The structural and functional organization of the cell nucleus has been investigated using three-dimensional reconstruction, immunoelectron microscopy, and high-resolution in situ autoradiography. Nuclear regions enriched in small nuclear ribonucleoprotein particles (snRNPs) form a reticular network within the nucleop...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Spector DL

更新日期：1990-01-01 00:00:00

abstract：:Bordetella pertussis, the causative agent of whooping cough, secretes several toxins implicated in this disease. One of these putative virulence factors is the adenylate cyclase (AC) toxin that elevates intracellular cAMP in eukaryotic cells to cytotoxic levels. This toxin is a bifunctional protein comprising both AC ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gross MK,Au DC,Smith AL,Storm DR

更新日期：1992-06-01 00:00:00

abstract：:The N-terminal 392 amino acids of the Drosophila kinesin alpha subunit (designated DKH392) form a dimer in solution that releases only one of its two tightly bound ADP molecules on association with a microtubule, whereas a shorter monomeric construct (designated DKH340) releases > or = 95% of its one bound ADP on asso...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Hackney DD

更新日期：1994-07-19 00:00:00

abstract：:We have examined the accumulation of newly synthesized nuclear proteins into nuclei during DNA repair synthesis in confluent WI-38 human diploid fibroblasts damaged with ultraviolet radiation or N-acetoxy-2-acetylaminofluroene. In contrast to a marked stimulation of DNA repair synthesis, stimulation of amino acid inco...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Stein GS,Park WD,Stein JL,Lieberman MW

更新日期：1976-05-01 00:00:00

abstract：:Granulocytes generate a "respiratory burst" of NADPH oxidase-dependent superoxide anion (O(2)(-*)) production that is required for efficient clearance of bacterial pathogens. Hv1 mediates a voltage-gated H(+) channel activity that is proposed to serve a charge-balancing role in granulocytic phagocytes such as neutroph...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Ramsey IS,Ruchti E,Kaczmarek JS,Clapham DE

更新日期：2009-05-05 00:00:00

abstract：:Bacterial intracellular symbiosis (endosymbiosis) is widespread in nature and impacts many biological processes. In holometabolous symbiotic insects, metamorphosis entails a complete and abrupt internal reorganization that creates a constraint for endosymbiont transmission from larvae to adults. To assess how endosymb...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Maire J,Parisot N,Galvao Ferrarini M,Vallier A,Gillet B,Hughes S,Balmand S,Vincent-Monégat C,Zaidman-Rémy A,Heddi A

更新日期：2020-08-11 00:00:00

abstract：:When a local mechanical perturbation is applied to the surface of a thin film of a mechanically interlocked molecule (a rotaxane), the molecules self-organize into periodic arrays of discrete dots or lines. The dimensionality of the nanostructures depends on whether the mechanical stimulus acts along a 1D line or over...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Biscarini F,Cavallini M,Kshirsagar R,Bottari G,Leigh DA,León S,Zerbetto F

更新日期：2006-11-21 00:00:00