Entropy of dialogues creates coherent structures in e-mail traffic.

abstract：:The intracellular localization of phytochrome was seen in dark-grown oat (Avena sativa L., cv. Garry) and rice (Oryza sativa L., cv. unknown) shoots after various light treatments using an indirect peroxidase-antiperoxidase antibody labeling method. Phytochrome is generally distributed throughout the cytoplasm in cell...

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

authors： Mackenzie JM Jr,Coleman RA,Briggs WR,Pratt LH

更新日期：1975-03-01 00:00:00

abstract：:The location of phosphate residues involved in specific centers for binding of metal ions in M1 RNA, the catalytic RNA subunit of RNase P from Escherichia coli, was determined by analysis of induction of cleavage of RNA by metal ions. At pH 9.5, Mg2+ catalyzes cleavage of M1 RNA at five principal sites. Under certain ...

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

authors： Kazakov S,Altman S

更新日期：1991-10-15 00:00:00

abstract：:Recent studies have suggested that Paleozoic hyperoxia enabled animal gigantism, and the subsequent hypoxia drove a reduction in animal size. This evolutionary hypothesis depends on the argument that gas exchange in many invertebrates and skin-breathing vertebrates becomes compromised at large sizes because of distanc...

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

authors： Kaiser A,Klok CJ,Socha JJ,Lee WK,Quinlan MC,Harrison JF

更新日期：2007-08-07 00:00:00

abstract：:Hypothalamic malonyl-CoA has been shown to function in global energy homeostasis by modulating food intake and energy expenditure. Little is known, however, about the regulation of malonyl-CoA concentration in the central nervous system. To address this issue we investigated the response of putative intermediates in t...

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

authors： Wolfgang MJ,Cha SH,Sidhaye A,Chohnan S,Cline G,Shulman GI,Lane MD

更新日期：2007-12-04 00:00:00

abstract：:The "disease-specific" (dsp) region next to the hrp gene cluster of Erwinia amylovora is required for pathogenicity but not for elicitation of the hypersensitive reaction. A 6.6-kb apparent operon, dspEF, was found responsible for this phenotype. The operon contains genes dspE and dspF and is positively regulated by h...

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

authors： Bogdanove AJ,Kim JF,Wei Z,Kolchinsky P,Charkowski AO,Conlin AK,Collmer A,Beer SV

更新日期：1998-02-03 00:00:00

abstract：:The role of cell surface immunoglobulin in helper T-cell-dependent B-cell activation was analyzed using a B-cell lymphoma, CH12, with known antigen specificity and activation properties similar to those of a resting B cell. Two sources of helper T cells were used, both selected such that they interact with H-2-encoded...

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

authors： LoCascio NJ,Haughton G,Arnold LW,Corley RB

更新日期：1984-04-01 00:00:00

abstract：:TIM-4, a member of the TIM family expressed on antigen-presenting cells, binds to phosphatidylserine exposed on the surface of apoptotic bodies. However, the significance of this interaction in vivo remains unknown because other receptors have been implicated in the clearance of apoptotic bodies and could compensate f...

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

authors： Rodriguez-Manzanet R,Sanjuan MA,Wu HY,Quintana FJ,Xiao S,Anderson AC,Weiner HL,Green DR,Kuchroo VK

更新日期：2010-05-11 00:00:00

abstract：:C6 astrocytoma cells contain beta-adrenergic receptors coupled to adenylate cyclase. A 2-hr exposure to l-isoproterenol results in an 80% decrease in cyclic AMP production in response to a subsequent challenge by l-isoproterenol (desensitization). This loss in responsiveness is paralleled by a 20-30% decrease in the a...

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

authors： Mallorga P,Tallman JF,Henneberry RC,Hirata F,Strittmatter WT,Axelrod J

更新日期：1980-03-01 00:00:00

abstract：:Synthetic bradykinin, a nonapeptide formed from alpha-2 globulin in plasma, injected intra-arterially or intraperitoneally in cats in doses of 10-50 mug, evoked activity in the central nervous system in pathways associated with the signaling of pain. Similar injections of bradykinin in intact normal cats and dogs evok...

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

authors： Lim RK,Krauthamer G,Guzman F,Fulp RR

更新日期：1969-07-01 00:00:00

abstract：:Although current demands for therapeutic mAbs are growing quickly, production methods to date, including in vitro mammalian tissue culture and transgenic animals, provide only limited quantities at high cost. Several tumor-associated antigens in tumor cells have been identified as targets for therapeutic mAbs. Here we...

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

authors： Brodzik R,Glogowska M,Bandurska K,Okulicz M,Deka D,Ko K,van der Linden J,Leusen JH,Pogrebnyak N,Golovkin M,Steplewski Z,Koprowski H

更新日期：2006-06-06 00:00:00

abstract：:The neuronal nucleus plays a vital role in information processing, but whether it supports computational functions such as paired-pulse facilitation, comparable to synapses, is unclear. Ca(2+)-dependent movement of calmodulin (CaM) to the nucleus is highly responsive to Ca(2+) entry through L-type channels and promote...

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

authors： Mermelstein PG,Deisseroth K,Dasgupta N,Isaksen AL,Tsien RW

更新日期：2001-12-18 00:00:00

abstract：:Corticosteroid hormones are critical for controlling metabolism, hydromineral balance, and the stress response in vertebrates. Although corticosteroid hormones have been well characterized in most vertebrate groups, the identity of the earliest vertebrate corticosteroid hormone has remained elusive. Here we provide ev...

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

authors： Close DA,Yun SS,McCormick SD,Wildbill AJ,Li W

更新日期：2010-08-03 00:00:00

abstract：:The delta-subspecies of protein kinase C (delta PKC) was purified to near homogeneity from the Triton X-100 extract of the rat brain particulate fraction by successive chromatographies on S-Sepharose fast flow, phenyl 5PW, heparin 5PW, hydroxyapatite, and Mono Q columns. The purified enzyme was a doublet with molecula...

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

authors： Ogita K,Miyamoto S,Yamaguchi K,Koide H,Fujisawa N,Kikkawa U,Sahara S,Fukami Y,Nishizuka Y

更新日期：1992-03-01 00:00:00

abstract：:Antibodies that modulate receptor function have great untapped potential in the control of stem cell differentiation. In contrast to many natural ligands, antibodies are stable, exquisitely specific, and are unaffected by the regulatory mechanisms that act on natural ligands. Here we describe an innovative system for ...

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

authors： Melidoni AN,Dyson MR,Wormald S,McCafferty J

更新日期：2013-10-29 00:00:00

abstract：:Nitrogen metabolism in bacteria and archaea is regulated by a ubiquitous class of proteins belonging to the P(II)family. P(II) proteins act as sensors of cellular nitrogen, carbon, and energy levels, and they control the activities of a wide range of target proteins by protein-protein interaction. The sensing mechanis...

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

authors： Rajendran C,Gerhardt EC,Bjelic S,Gasperina A,Scarduelli M,Pedrosa FO,Chubatsu LS,Merrick M,Souza EM,Winkler FK,Huergo LF,Li XD

更新日期：2011-11-22 00:00:00

abstract：:The patterns of variations in fisheries time series are known to result from a complex combination of species and fisheries dynamics all coupled with environmental forcing (including climate, trophic interactions, etc.). Disentangling the relative effects of these factors has been a major goal of fisheries science for...

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

authors： Rouyer T,Fromentin JM,Ménard F,Cazelles B,Briand K,Pianet R,Planque B,Stenseth NC

更新日期：2008-04-08 00:00:00

abstract：:Six Rhesus monkeys between 24 and 29 years of age received unilateral transections of the fornix. Three monkeys then received intraventricular transplants of polymer-encapsulated baby hamster kidney (BHK) fibroblasts that had been genetically modified to secrete human nerve growth factor (hNGF). The remaining three mo...

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

authors： Kordower JH,Winn SR,Liu YT,Mufson EJ,Sladek JR Jr,Hammang JP,Baetge EE,Emerich DF

更新日期：1994-11-08 00:00:00

abstract：:Using a tissue culture system based on a nearly pure population of avian precartilage mesenchymal cells, we have found that ambient glucose levels as little as 50% lower, or 100% higher, than normally present in embryonic sera are deleterious to cartilage development, as measured by the accumulation of highly sulfated...

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

authors： Leonard CM,Bergman M,Frenz DA,Macreery LA,Newman SA

更新日期：1989-12-01 00:00:00

abstract：:Epidermal growth factor (EGF) stimulates membrane protein phosphorylation in a human cell line, A-431. The known hepatic mitogenic action of EGF and the reduction in EGF receptor number that occurs during liver regeneration led us to study whether EGF-dependent protein kinase activity was present in rat liver and whet...

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

authors： Rubin RA,O'Keefe EJ,Earp HS

更新日期：1982-02-01 00:00:00

abstract：:Chromatin boundaries or insulators modulate enhancer-promoter interactions in complex genetic loci. However, the mechanism underlying insulator activity is not known. Previous studies showed that the activity of the Drosophila suHw insulator is abolished by the tandem arrangement (pairing) of the insulator elements, s...

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

authors： Majumder P,Cai HN

更新日期：2003-04-29 00:00:00

abstract：:We have previously described how T and natural killer (NK) lineage commitment proceeds from common T/NK progenitors (p-T/NK) in the murine fetal thymus (FT), with the use of a clonal assay system capable of discriminating p-T/NK from unipotent T or NK lineage-committed progenitors (p-T and p-NK, respectively). The mol...

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

authors： Ikawa T,Fujimoto S,Kawamoto H,Katsura Y,Yokota Y

更新日期：2001-04-24 00:00:00

abstract：:We construct a C*-algebra that has only one irreducible representation up to unitary equivalence but is not isomorphic to the algebra of compact operators on any Hilbert space. This answers an old question of Naimark. Our construction uses a combinatorial statement called the diamond principle, which is known to be co...

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

authors： Akemann C,Weaver N

更新日期：2004-05-18 00:00:00

abstract：:Inorganic elements, although required only in trace amounts, permit life and primary productivity because of their functions in catalysis. Every organism has a minimal requirement of each metal based on the intracellular abundance of proteins that use inorganic cofactors, but elemental sparing mechanisms can reduce th...

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

authors： Kropat J,Gallaher SD,Urzica EI,Nakamoto SS,Strenkert D,Tottey S,Mason AZ,Merchant SS

更新日期：2015-03-03 00:00:00

abstract：:Dimerization of human immunodeficiency virus type 1 protease (HIV-1 PR) monomers is an essential prerequisite for viral proteolytic activity and the subsequent generation of infectious virus particles. Disruption of the dimer interface inhibits this activity as does formation of heterodimers between wild-type and defe...

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

authors： McPhee F,Good AC,Kuntz ID,Craik CS

更新日期：1996-10-15 00:00:00

abstract：:The colony-stimulating factors (CSFs) greatly influence mature macrophage function in vitro: macrophage (M)-CSF induces maturation of monocytes and enhances differentiated cell function; granulocyte-macrophage (GM)-CSF stimulates a variety of antimicrobial functions. In vivo M-CSF is thought to promote differentiation...

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

authors： De Nichilo MO,Burns GF

更新日期：1993-03-15 00:00:00

abstract：:Replication through damaged sites in DNA requires in Escherichia coli the SOS stress-inducible DNA polymerase V (UmuC), which is specialized for lesion bypass. Homologs of the umuC gene were found on native conjugative plasmids, which often carry multiple antibiotic-resistant genes. MucB is a UmuC homolog present on p...

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

authors： Goldsmith M,Sarov-Blat L,Livneh Z

更新日期：2000-10-10 00:00:00

abstract：:Sympathetic ganglia and some peripheral tissues of adult guinea pig and cat were analyzed by the indirect immunofluorescence technique with antisera to catecholamine-synthesizing enzymes and some peptides. In the guinea pig, noradrenergic neurons could be subdivided into three populations containing respectively (i) s...

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

authors： Lundberg JM,Hökfelt T,Anggård A,Terenius L,Elde R,Markey K,Goldstein M,Kimmel J

更新日期：1982-02-01 00:00:00

abstract：:Down-regulation of mitogenic signaling in mammalian cells relies in part on endosomal trafficking of activated receptors into lysosomes, where the receptors are degraded. These events are mediated by ubiquitination of the endosomal cargo and its consequent sorting into multivesicular bodies that form at the surfaces o...

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

authors： Lu Q,Hope LW,Brasch M,Reinhard C,Cohen SN

更新日期：2003-06-24 00:00:00

abstract：:Adeno-associated virus (AAV) is a small human Dependovirus whose low immunogenicity and capacity for long-term persistence have led to its widespread use as vector for gene therapy. Despite great recent successes in AAV-based gene therapy, further improvements in vector technology may be hindered by an inadequate unde...

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

authors： Smith-Moore S,Neil SJD,Fraefel C,Linden RM,Bollen M,Rowe HM,Henckaerts E

更新日期：2018-04-10 00:00:00

abstract：:Recently, diffraction elements that reverse the color sequence normally observed in planar diffraction gratings have been found in the wing scales of the butterfly Pierella luna. Here, we describe the creation of an artificial photonic material mimicking this reverse color-order diffraction effect. The bioinspired sys...

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

authors： England G,Kolle M,Kim P,Khan M,Muñoz P,Mazur E,Aizenberg J

更新日期：2014-11-04 00:00:00