Spontaneous eyelid closures link vigilance fluctuation with fMRI dynamic connectivity states.

abstract：:Peptide nucleic acid (PNA) is a DNA mimic that has shown considerable promise as a lead compound for developing gene therapeutic drugs. We report that PNAs targeted to functional and accessible sites in ribosomal RNA can inhibit translation in an Escherichia coli cell-free transcription/translation system, with 50% re...

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

authors： Good L,Nielsen PE

更新日期：1998-03-03 00:00:00

abstract：:Kinetic partitioning is predicted to be a general mechanism for proteins to fold into their well defined native three-dimensional structure from unfolded states following multiple folding pathways. However, experimental evidence supporting this mechanism is still limited. By using single-molecule atomic force microsco...

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

authors： Peng Q,Li H

更新日期：2008-02-12 00:00:00

abstract：:Nicotine exposure diminishes the protective breathing and arousal responses to stress (hypoxia). By exacerbating sleep-disordered breathing, this disturbance could underpin the well established association between smoking and the increased risk of sudden infant death syndrome. We show here that the protective response...

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

authors： Cohen G,Han ZY,Grailhe R,Gallego J,Gaultier C,Changeux JP,Lagercrantz H

更新日期：2002-10-01 00:00:00

abstract：:The induction of heat shock proteins in three species of Leishmania, L. tropica, L. enrietti, and L. donovani is reported. When cultures of promastigotes are shifted from 26 degrees C to 37 degrees C or 40 degrees C, the synthesis of proteins with apparent molecular weights of 88,000, 74,000, and 54,000 is stimulated....

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

authors： Lawrence F,Robert-Gero M

更新日期：1985-07-01 00:00:00

abstract：:Online education is rapidly expanding in response to rising demand for higher and continuing education, but many online students struggle to achieve their educational goals. Several behavioral science interventions have shown promise in raising student persistence and completion rates in a handful of courses, but evid...

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

authors： Kizilcec RF,Reich J,Yeomans M,Dann C,Brunskill E,Lopez G,Turkay S,Williams JJ,Tingley D

更新日期：2020-06-30 00:00:00

abstract：:Mouse bone marrow-derived Lin(-)-Sca-1(+) endothelial progenitor cell (EPC) has pluripotent abilities such as supporting neovascularization. Vascular endothelial growth factor (VEGF) receptor 1 (VEGFR1) (Flt1) recognizes various VEGF isoforms and is critically implicated in a wide range of physiological and pathologic...

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

authors： Qi JW,Qin TT,Xu LX,Zhang K,Yang GL,Li J,Xiao HY,Zhang ZS,Li LY

更新日期：2013-08-20 00:00:00

abstract：:2fTGH is a human cell line containing the selectable marker guanine phosphoribosyltransferase regulated by alpha interferon (IFN-alpha). Two IFN-alpha-unresponsive mutants were isolated previously at a low frequency (ca. 10(-8)) by selecting mutagenized 2fTGH cells in selective medium containing 6-thioguanine and IFN-...

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

authors： McKendry R,John J,Flavell D,Müller M,Kerr IM,Stark GR

更新日期：1991-12-15 00:00:00

abstract：:Expression of the bacterial RecA protein in plants stimulates homologous recombination in tobacco. Here we show that RecA plays a direct role in DNA strand exchange in vivo. The number of sister chromatid exchanges (SCEs) was increased 2.4-fold over wild type in transgenic tobacco plants expressing a nuclear-targeted ...

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

authors： Reiss B,Schubert I,Köpchen K,Wendeler E,Schell J,Puchta H

更新日期：2000-03-28 00:00:00

abstract：:Much of the success of Plasmodium falciparum in establishing persistent infections is attributed to immune evasion through antigenic variation. This process involves periodically exchanging variants of the major surface antigen PfEMP1, a protein also responsible for parasite cytoadherence. PfEMP1 is encoded by genes o...

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

authors： Ralph SA,Scheidig-Benatar C,Scherf A

更新日期：2005-04-12 00:00:00

abstract：:The coat protein of bacteriophage MS-2 was cleaved with cyanogen bromide to yield three fragments, possessing the sequence 1-88 (P1), 89-108 (P2), and 109-129 (P3), respectively. The mixture of peptides P2 and P3, which could not be separated, was found capable of inhibiting the neutralization of the phage by antiseru...

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

authors： Langbeheim H,Arnon R,Sela M

更新日期：1976-12-01 00:00:00

abstract：:Like all aliphatic amines, the polyamines spermine and spermidine are physical quenchers of singlet molecular oxygen (1O2*). The rate constants of these processes were determined in vitro with photochemically generated 1O2* and the hydrocarbon rubrene as substrate, in pyridine. At millimolar concentration, spermine an...

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

authors： Khan AU,Mei YH,Wilson T

更新日期：1992-12-01 00:00:00

abstract：:In the presence but not in the absence of pokeweed mitogen (PWM), monoclonal antibodies against HLA-DR antigens 147 and 164 helped highly purified B lymphocytes to proliferate and mature to Ig-secreting cells. In contrast, neither anti-DR antibody 231 nor the UCHT1 monoclonal anti-human T cell antibody (both of the sa...

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

authors： Palacios R,Martinez-Maza O,Guy K

更新日期：1983-06-01 00:00:00

abstract：:The polypeptide precursor pr76 to the internal viral group specific (gs) antigen proteins of Rous sarcoma virus, synthesized in a cell-free system of ascites cells, has been processed in vitro into the viral proteins by purified viral protein p15 as well as by disrupted Rous sarcoma virus. Disrupted Rauscher murine le...

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

authors： von der Helm K

更新日期：1977-03-01 00:00:00

abstract：:Coimmunoprecipitation of members of the phytochrome red/farred photoreceptor family from plant extracts has been used to analyze their heteromeric binding interactions. Phytochrome (phy)B or phyD apoproteins with six myc epitopes fused to their N termini are biologically active when expressed in Arabidopsis. Immunopre...

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

authors： Sharrock RA,Clack T

更新日期：2004-08-03 00:00:00

abstract：:Cyclooxygenase (COX)-2, a rate-limiting enzyme of prostaglandin (PG) production, is overexpressed in colorectal adenomas and adenocarcinomas, and its inhibition by nonsteroidal antiinflammatory drugs protects against colorectal cancer. Mechanisms of cancer promotion by COX-2 are not fully understood, but signaling thr...

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

authors： Nishihara H,Kizaka-Kondoh S,Insel PA,Eckmann L

更新日期：2003-07-22 00:00:00

abstract：:Antigenic variation of infectious organisms is a major factor in evasion of the host immune response. However, there has been no definitive demonstration of this phenomenon in the malaria parasite Plasmodium falciparum. In this study, cloned parasites were examined serologically and biochemically for the expression of...

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

authors： Biggs BA,Goozé L,Wycherley K,Wollish W,Southwell B,Leech JH,Brown GV

更新日期：1991-10-15 00:00:00

abstract：:Thyrotropin-releasing hormone (TRH) binds to specific receptors on GH4C1 pituitary tumor cells. A fluorescently labeled analog of TRH was synthesized by coupling pGlu-His-ProNH(CH2)6NH2 to fluorescein isothiocyanate. The fluorescein-labeled peptide (FL-TRH) stimulated prolactin synthesis and release by GH4C1 cultures ...

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

authors： Halpern J,Hinkle PM

更新日期：1981-01-01 00:00:00

abstract：:While we have come to appreciate the architectural complexity of microbially synthesized secondary metabolites, far less attention has been paid to linking their structural features with possible modes of action. This is certainly the case with tropodithietic acid (TDA), a broad-spectrum antibiotic generated by marine...

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

authors： Wilson MZ,Wang R,Gitai Z,Seyedsayamdost MR

更新日期：2016-02-09 00:00:00

abstract：:The type of cytokines produced during T cell responses determines susceptibility or resistance to many pathogens and influences the development of autoimmunity and allergy. To define the role of individual accessory molecules in cytokine production during primary immune responses, Drosophila cell lines expressing muri...

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

authors： Luksch CR,Winqvist O,Ozaki ME,Karlsson L,Jackson MR,Peterson PA,Webb SR

更新日期：1999-03-16 00:00:00

abstract：:The spectra of the alpha, beta, and gamma forms of zinc monoarsanilazotyrosine-248 carboxypeptidase A are indistinguishable. At pH 8.2 their crystals are yellow, while their solutions are red, lambda(max) 510 nm. Absorption and circular dichroism-pH titrations of the modified zinc and apoenzymes demonstrate that the a...

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

authors： Johansen JT,Vallee BL

更新日期：1973-07-01 00:00:00

abstract：:Grasslands cover more than 20% of the Earth's terrestrial surface, and their rise to dominance is one of the most dramatic events of biome evolution in Earth history. Grasses possess two main photosynthetic pathways: the C(3) pathway that is typical of most plants and a specialized C(4) pathway that minimizes photores...

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

authors： Edwards EJ,Smith SA

更新日期：2010-02-09 00:00:00

abstract：:Infection of cultured cells with lytic animal viruses often results in the selective inhibition of host protein synthesis, whereas viral mRNA is efficiently translated under these circumstances. This phenomenon, known as "shut off," has been well described at the molecular level for some viruses, but there is not yet ...

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

authors： Toribio R,Ventoso I

更新日期：2010-05-25 00:00:00

abstract：:Methods to acutely manipulate protein interactions at the subcellular level are powerful tools in cell biology. Several blue-light-dependent optical dimerization tools have been developed. In these systems one protein component of the dimer (the bait) is directed to a specific subcellular location, while the other com...

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

authors： Benedetti L,Barentine AES,Messa M,Wheeler H,Bewersdorf J,De Camilli P

更新日期：2018-03-06 00:00:00

abstract：:Ethylene inhibits hypocotyl elongation in etiolated Arabidopsis seedlings. However, when Arabidopsis was grown in the light in the presence of ethylene or its precursor 1-aminocyclopropane-1-carboxylic acid (ACC), a marked induction of hypocotyl elongation occurred. This resulted from an increase in cell expansion rat...

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

authors： Smalle J,Haegman M,Kurepa J,Van Montagu M,Straeten DV

更新日期：1997-03-18 00:00:00

abstract：:Theories of evolution that state natural selection acts on individuals have been modified to include multiple levels of selection. Here we demonstrate in chimeric protochordates that primitive germ cell (pgc) and somatic cell (psc) lineages have traits that also make them likely units of natural selection. Specificall...

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

authors： Stoner DS,Rinkevich B,Weissman IL

更新日期：1999-08-03 00:00:00

abstract：:The Ten-Eleven-Translocation 2 (TET2) gene encodes a member of TET family enzymes that alters the epigenetic status of DNA by oxidizing 5-methylcytosine to 5-hydroxymethylcytosine (5hmC). Somatic loss-of-function mutations of TET2 are frequently observed in patients with diverse myeloid malignancies, including myelody...

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

authors： Ko M,Bandukwala HS,An J,Lamperti ED,Thompson EC,Hastie R,Tsangaratou A,Rajewsky K,Koralov SB,Rao A

更新日期：2011-08-30 00:00:00

abstract：:Mechanisms leading to down-regulation of activated microglia and astrocytes are poorly understood, in spite of the potentially detrimental role of activated glia in neurodegeneration. Prostaglandins, produced both by neurons and glia, may serve as mediators of glial and neuronal functions. We examined the influence of...

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

authors： Petrova TV,Akama KT,Van Eldik LJ

更新日期：1999-04-13 00:00:00

abstract：:Incorporation of 2-acyl spin-labeled lecithin into the phosphatidylcholine protein from bovine liver results in an immobilization of the spin-label at the methyl and the carboxyl terminal end of the acyl chain. The nitroxide group on the protein-bound lecithin molecule is not accessible to ascorbate. This suggests tha...

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

authors： Devaux PF,Moonen P,Bienvenue A,Wirtz KW

更新日期：1977-05-01 00:00:00

abstract：:Chromosome region 11p15.5 harbors unidentified genes involved in neoplasms and in the genetic disease Beckwith-Wiedemann syndrome. The genetic analysis of a 170-kb region at 11p15.5 between loci D11S601 and D11S679 resulted in the identification of six transcriptional units. Three genes, hNAP2, CDKN1C, and KVLQT1, are...

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

authors： Schwienbacher C,Sabbioni S,Campi M,Veronese A,Bernardi G,Menegatti A,Hatada I,Mukai T,Ohashi H,Barbanti-Brodano G,Croce CM,Negrini M

更新日期：1998-03-31 00:00:00

abstract：:We describe a Kappa-on-Heavy (KoH) mouse that produces a class of highly diverse, fully human, antibody-like agents. This mouse was made by replacing the germline variable sequences of both the Ig heavy-chain (IgH) and Ig kappa (IgK) loci with the human IgK germline variable sequences, producing antibody-like molecule...

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

authors： Macdonald LE,Meagher KA,Franklin MC,Levenkova N,Hansen J,Badithe AT,Zhong M,Krueger P,Rafique A,Tu N,Shevchuk J,Wadhwa S,Ehrlich G,Bautista J,Grant C,Esau L,Poueymirou WT,Auerbach W,Morton L,Babb R,Chen G,Huang

更新日期：2020-01-07 00:00:00